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High fluorine content fluororubber (FKM) was used as the research object, the high temperature medium resistance of high fluorine content FKM vulcanizates in a variety of aero-engine lubricanting oils was investigated, and the changes in physical and mechanical properties of high fluorine content FKM vulcanizates caused by different types of lubricanting oils were studied. The results showed that the high fluorine content FKM vulcanizates could still maintain good compression resilience after aging in lubricating oil at 200 ℃ for 72 h, the volume change rate was lower than 12%, the mechanical properties declined slightly, and the Shore A hardness decreased significantly. The mechanical pro-perty attenuation and volume change rate of high fluorine content FKM vulcanizate were different for different kinds of oil. The corrosion of lubricating oil on high fluorine content FKM vulcanizate at high temperature included physical infiltration and che-mical corrosion.

A perforated leakage occurred in a gas field sewage storage tank in service. In order to analyze the cause of the perforation and to clarify the critical wall thicknesses of the common perforated points of the sewage storage tank, the micro hardness tester, universal testing machine, metallurgical microscope, scanning electron microscope (SEM), energy spectrometer (EDS) and X - ray diffraction (XRD) were used to analyze the physical and chemical properties of the storage tank, perforation characteristics, the morphology and composition of corrosion products. Results showed that the physical and chemical properties of the material met the requirements; the corrosion products were loose, mainly containing Fe2O3 and having a small amount of FeS. The corrosion pit developed from the inner wall of the storage tank to the outer wall, and the depth of the corrosion pit was about 2.6 mm. Therefore, the perforation mechanism and process of the storage tank could be destribed as follow: the water and corrosive medium penetrated between the layer and the inner wall of the storage tank, leading to an oxygen corrosion (the main corrosion) and a SRB corrosion (the auxiliary corrosion), and as a result, local corrosion pits formed on the inner wall of the storage tank. When the depth of the corrosion pit reached 65% of the initial wall thickness of the storage tank, the stress level at the bottom of the pit exceeded the internal pressure resistance of the storage tank, resulting in a perforation leakage of the storage tank.

A novel proximity method-RFID dynamic positioning method was presented,using a moving radio frequency identification (RFID) reader to accurately position the target based on reference tag arrays.The major advantage of the method was that through reading tags without any measurement data,e.g.,the time of arrival (TOA) or the received signal strength indication (RSSI),it improved the accuracy of positioning target based on reference tags and a moving reader.The algorithm was simple but useful.Based on the performance of the prototype system,it demonstrated that the proposed system could accurately position in one of the smallest reference tag cell (within dozens of centimeters) and could be deployed easily with low cost,thus has potential application in RFID warehouse management.

In a time division duplex（TDD） system,the channel state information could be easily obtained at the trans-mitter side without feedback due to channel reciprocity and it could be used to increase dramatically the spectral effi-ciency of a multi-input multi-output（MIMO） system.However,the interference structure between transmission directions did not necessarily correlate at all.In such a case,the downlink modulation/coding parameters based on the uplink meas-urements might lead to excessively high frame error rates（FER）.Therefore,a simple closed-loop feedback method of in-terference adaptation was proposed,which made the transmit-side estimated interference be able to track the instantane-ous receive-side interference dynamically,and its performance in adaptive TDD MIMO-OFDM systems with HARQ was studied.Simulation results show that the tracking performance is well and the target FER requirement can be guaranteed.

The experiment took the edible fungus residue as research object, to improve the crude protein content in fermentation product. Single factor experiment and orthogonal experiment were used to investigate the effects of different factors on the crude protein content in the solid fermentation of edible fungus residue, and to find the optimal combination of fermentation parameters. The nutrient content before and after fermentation was compared under the optimal process parameters. The results showed that the order of importance of the factors affecting the crude protein content in the fermented products was the ratio of material to liquid > fermentation temperature > inoculation amount of seed liquid > fermentation time. The optimal fermentation parameters were fermentation temperature 30 °C, material liquid ratio 3.0 g/mL, fermentation time 96 h and seed liquid inoculation amount 25%. The crude protein content of fermentation product was 22.37%. Compared with before fermentation, the crude protein content in fermented product was significantly increased (P<0.05), the cellulose and hemicellulose content were significantly decreased (P<0.05) . The study indicates that the solid state fermentation of edible mushroom residue by inoculating mixed bacteria can produce higher quality protein feed and effectively improve the feeding nutritional value of mushroom residue. [ABSTRACT FROM AUTHOR]

Objective This study further explores the stromal cell-derived factor-1 (SDF-1)/chemokine receptor 4 (CXCR4) signaling axis mechanism in temporomandibular joint osteoarthritis (OA) by detecting the changes in CXCR4, interleukin (IL)-6, and collagen X expression in the ATDC5 cell line stimulated by the cyclic tensile strain and SDF-1. Methods Insulin-transferrin-transferrin-selenium(ITS) was used to induce ATDC5 cells to differentiate into chondrocyte-like cells. After three weeks, the cells were divided into two groups: those with and without cyclic tensile strain. These groups were further divided into the negative control and SDF-1 groups. Strain force of 20% was applied. After 12 h, the total proteins were extracted from cells of the four groups, and Western blot analysis was used to detect the changes in CXCR4, IL-6, and collagen X expression. Results SDF-1 could enhance CXCR4, IL-6, and collagen X expressions in the chondrocytes, and 20% tensile strain force could further upregulate the three factors. Conclusion Under abnormal tensile force, SDF-1 can upregulate its specific receptor CXCR4, thus increasing its binding efficiency and resulting in the activation of the SDF-1/CXCR4 axis. This condition enhances the expressions of IL-6 and other inflammatory factors and directly damages to cartilage tissue. Such damage directly promotes chondrocyte hypertrophy, which enhances collagen X expression. [ABSTRACT FROM AUTHOR]

As an improvement version of empirical mode decomposition (EMD), local characteristic-scale decomposition (LCD) also has the problem of mode mixing. The noise-assisted methods, such as ensemble EMD (EEMD) and complete EEMD (CEEMD), are effective ways to restrain the mode mixing. However, pseudo-components are easily generated by them and the obtained components sometimes do not meet the definition of IMF. A novel signal processing method called complete ensemble LCD (CELCD) is proposed to resolve mode mixing involved in LCD. Also, the comparisons between CELCD and CEEMD are studied by analyzing simulation signal, and the results indicate that CELCD could effectively restrain the mode mixing of LCD and generate more precise components. The rotor rubbing fault diagnosis verifies the validity of the proposed method. [ABSTRACT FROM AUTHOR]

Variable predictive model based class discriminate ( V P M C D ) is a new class discriminate approach, however, the choice of model type exists subjectivity. Combining the global optimization performance of genetic algorithm ( G A ), a method of fault intelligent diagnosis based on G A and VPMCD is presented to solve the problem of selecting model type in the course of machinery fault diagnosis by using VPMCD. Firstly, multiple weak Variable predictive models ( V P M s ) can be established through samples training. Secondly, after G A is used to optimize the weights matrix of each weak V P M, the optimal weights matrix is obtained. Lastly, optimal weights matrix is exploited to get optimal feature variables predictions by weight fusion for the values, which are predicted by the weak VPMs for the test samples, and fault types are identified according to the minimum error square sum as discrimination function simultaneously. It is demonstrated from the diagnosis experiment of roller bearings that the proposed method of intelligent diagnosis based on G A and VPMCD can improve the accuracy rate and robustness of diagnosis system. [ABSTRACT FROM AUTHOR]

Variable predictive model based class discriminate (VPMCD) is a new pattern recognition approach, which takes full advantage of the inhere relation between the feature value. The conception of LMD energy moment was presented in this paper. Aimed at the inhere relation between the feature value of roller bearing, combing the LMD energy moment and VPMCD, a novel intelligent fault diagnosis method was proposed. Firstly, the complicated non-stationary original vibration signal was de- composed into a set of product function components. Secondly, correlation analysis method was used to remove pseudo-components and the energy moment of real PF components with signal feature was extracted as eigenvector to express the fault information adequately. Lastly, VPMCD was served as the approach of pattern recognition to identify roller bearing fault type. The simulation results demonstrate the energy moment of PF components can reflect essential feature of non-stationary signal. The analysis results from practical roller bearings fault vibration signal show that the proposed method can be applied to small sample multiple classification intelligent fault diagnosis of roller bearing effectively. [ABSTRACT FROM AUTHOR]

Studies the timing dispersion of clock mechanisms by theoretical analysis and computer simulation. Based on dynamic analysis of the mechanism, 3D model building and dynamic simulation, influence of escapement mechanism parameter to timing of clock mechanisms is well understood. The result indicates that the diameter of escape wheel addendum, center distance of escape wheel and pendulum have their significant influence on the timing of clock mechanism. [ABSTRACT FROM AUTHOR]

The biological characteristics,agronomic traits,yield traits,stress resistance,quality and photosynthetic characteristics among six lily varieties were compared in order to screen out the excellent lily varieties suitable for spread planting in Hunan province. Lilium longiflorum had the longest growth period,246 days,among these six lily varieties,while others were about 170 days. The leaves of L.longiflorum,self-selected variety,L. lancifolium and L. dauricum had higher chlorophyll content. No obvious difference was found in net photosynthetic rate,stomatal conductance,transpiration rate and intercellular CO2 concentration among all varieties. The self-selected variety had the highest theoretical and actual yield,2 543. 03,1 608. 65 kg per Mu(1 Mu≈666. 7 m2),respectively,but contents of polysaccharides and flavones in bulbs were lower. All of these six lily varieties can sowing,seedling emergence,growth,flowering,mature harvest in Hunan province. L. dauricum and L. lancifolium would be provided for edible lily. L. brownie and the self-selected variety are highly susceptible varieties. L. dauricum and L. lancifolium are suitable to plant widely in disease-prone regions,due to their strong resistance. L. brownie and L. lancifolium are preferred varieties for medicinal and food using for their good quality and higher contents of polysaccharides and flavones. L. davidii had lower theoretical and actual yield,so planting extension of it should be taken into account.

Volatile organic compounds (VOCs) and odors, which pose potential hazards to human health and the ecosystem, are two of the most important pollutants emitted from the pharmaceutical fermentation industry. Currently, basic research on the characteristics of the pollution and effective prevention technology for VOCs and odors emitted from the pharmaceutical fermentation industry are limited. Specifically, the pharmaceutical fermentation industry lacks adequate theoretical guidance on the supervision and control of VOCs and odors, and some companies even face relocations. Using the pharmaceutical fermentation industry as the study object, the pollution characteristics of VOCs and odors emitted from different production workshops, sewage treatment stations, and the disposal of pharmaceutical residues were assessed. Based on the studies above, the progress of research into representative control technologies were also reviewed systematically. For VOCs and odors control in the pharmaceutical fermentation industry, four suggestions for future research were proposed:① The production processes should be optimized, and the discharge of pollution should be reduced throughout the entire processes; ② Basic research should be carried out on the pollution characteristics of the VOCs and odors emitted from the pharmaceutical fermentation industry, and a rapid and effective method to trace the sources of VOCs and odors should be established; ③ A comprehensive evaluation of control technologies should be conducted, taking cost and efficiency into account; ④ Emission standards and technical orders for VOCs and odors in the pharmaceutical fermentation industry should be formulated and implemented immediately.

Objective: The latency-intensity function (LIF) of wave V from click ABR of some deaf children showed great variation. We attempted to find out the intrinsic reasons., Method: The children recieved tone-burst ABR test., Result: Frequencies from 0.5-4.0 kHz have been tested and the thresholds of tone-burst ABR were recorded. The average thresholds of steeply LIF children at 0.5-4.0 kHz were (93.13 ± 7.04), (79.37 ± 7.72), (69.38 ± 8.54) (66.25 ± 8.06) dB respectively, while the average thresholds of shallower LIF children at these 4 frequencies were (65.00 ± 7.32) (68.13 ± 6.55) (70.63 ± 6.80) (78.12 ± 8.34) dB respectively., Conclusion: The results imply that the child with steeply LIF may have more hearing loss at frequencies 0.5 and 1 kHz than those with shallower LIF. LIF may predict the audiogram configuration.

The aim of this study was to design a simple, economic, with high Common Mode Rejection Ratio (CMRR), preamplifier and multi-channel masticatory muscle surface electromyography (sEMG) signal acquisition system assisting to diagnose temporomandibular disorders (TMD). We used the USB interface technology in the EMG data with the aid of the windows to operate system and graphical interface. Eight patients with TMD and eight controls were analyzed separately using this system. In this system, we analyzed sEMG by an optional combination of time domain, frequency domain, time-frequency, several spectral analysis, wavelets and other special algorithms under multi-parameter. Multi-channel sEMG System of Masticatory Muscles is a simple, economic system. It has high sensitivity and specificity. The sEMG signals were changed in patients with TMD. The system would pave the way for diagnosis TMD and help us to assess the treatment effect. A novel and objective method is provided for diagnosis and treatment of oral-maxillofacial disease and functional reconstruction.

Objective: To investigate the effect and the possible mechanism of continuous hemofiltration in the treatment of traumatic patients with refractory acute cephalocele., Methods: Continuous venous-venous hemofiltration (CVVH) was applied to 9 traumatic patients with refractory acute cephalocele after craniotomy. The changes in patients' physical signs, electrolytes, blood gas analysis, biochemical and blood clotting indexes as well as the outcome were observed., Results: (1) The later the CVVH started, the worse the disorders became such as unstable body temperature, respiratory rate, heart rate, blood pressure and abnormal blood gas analysis. The most significant abnormality emerged with a delay of 12 hours. The above abnormalities returned to normal and kept stable within 12 hours of CVVH. CVVH maintained body temperature in hypothermic state, and serum lactic acid was kept at a low level without disturbance of blood coagulation function. (2) The duration between occurrence of cephalocele and beginning of CVVH was 2-16 hours, with a mean of (5.4±5.1) hours, the duration of CVVH was 23-129 hours, with a mean of (75.7±34.3) hours, and the net volume of liquid balance (NVLB) was -1.2-3.1 L, with a mean of (0.76±1.46) L. Height of encephalocele over skull window (HEOSW) was 51.8±10.0 mm and 51.0±10.0 mm before and 72 hours after CVVH. NVLB and HEOSW did not show obvious correlation with the prognosis of the patients. (3) Four patients survived, and 2 patients showed satisfactory outcome with Glasgow outcome scale (GOS) over 12 after follow-up for 3 months, and 2 patients showed improvement with GOS of 8 but in vegetative state 3 months later. Five patients died of respiratory failure and multiple organ dysfunction syndrome (MODS) 9-35 days after the termination of CVVH., Conclusions: CVVH was safe and effective in certain extent in the treatment of refractory acute cephalocele. The direct causes of death of the patients were complications instead of the cephalocele itself. The outcomes of the patients were related to the time of beginning of CVVH and the duration of CVVH, and there was nothing to do with the NVLB and the HEOSW. The study implicated that the effect of CVVH on these patients was not brain-dehydration solely. It also exerted certain effect on regulating water-electrolyte balance, acid-base balance and body temperature.

Objective: To investigate the safety and effects of early bronchoscopy on atelectasis of the ventilation patients, whom had experienced craniotomy for severe cranial trauma and hemorrhage., Methods: Fifty-five patients suffered from severe cranial trauma and hemorrhage with Glascow coma scores (GCS) less than 8 complicated by atelectasis after craniotomy were early given sputum suction by bronchoscope via extratracheal intubation and broncho-alveolar lavage (BAL) during tracheal intubation and mechanical ventilation. During the treatment, patients' consciousness, vital signs and arterial blood gas were closely monitored. The relevant data, before, during (5, 10, and 25 minutes), bronchoscopy treatment completed and 30 minutes after bronchoscopy, were recorded and analyzed., Results: Eighty-two time of bronchoscopies and 111 time of local BALs in 55 patients were completed and were effective for atelectasis. The patient's GCS (5.6±2.5 vs. 5.4±2.6, P>0.05), heart rate (HR), respiratory rate (RR), systolic blood pressure (SBP), blood oxygenous saturation (SaO(2)) were not deteriorated during bronchoscopy. Compared with pre-bronchoscopy, the HR and SBP decreased (HR: 88.2±14.2 bpm vs. 98.2±18.3 bpm, SBP: 110.6±18.2 mm Hg vs. 118.4±18.5 mm Hg, both P<0.05), and SaO(2) increased (0.982±0.022 vs. 0.945±0.035, P<0.05), pH, arterial partial pressure of oxygen (PaO(2)) and arterial partial pressure of carbon dioxide (PaCO(2)) had no significant changes during bronchoscopy. There was obviously increased in PaO(2) (84.5±14.4 mm Hg, 81.6±18.2 mm Hg vs. 76.2±15.4 mm Hg, both P<0.05), and decreased in PaCO(2) (27.0±12.8 mm Hg, 29.3±18.2 mm Hg vs. 36.5±11.6 mm Hg, both P<0.05) respectively, significantly decreased in alveolar arterial pressure of oxygen difference [P ((A-a))O(2)] at 10 minutes and 25 minutes, and at the time bronchoscopy treatment completed and the time 30 minutes after compared with before bronchoscopy (36.1±4.7 mm Hg, 32.4±6.2 mm Hg, 32.5±5.2 mm Hg, 31.2±7.2 mm Hg vs. 38.5±5.6 mm Hg, all P<0.05). All patients had not encounter side effects related with bronchoscopy and ventilation., Conclusion: The bronchoscope via extratracheal intubation for sputum suction and BAL were safe and effective treatment to the patients suffered from severe cranial trauma or hemorrhage complicated by atelectasis after craniotomy during mechanical ventilation, without obvious changes of the vital signs.

Objective: To investigate the clinicopathologic features, immunophenotyping, differential diagnoses and prognosis of histiocytic sarcoma (HS)., Methods: The clinical and pathologic findings of 4 cases of HS were reviewed. The samples were used for paraffin section, HE stain, immunohistochemistry stain by EnVision method, electron microscope observation. Follow-up information was available in all patients., Results: The age of patients, 2 males and 2 females, ranged from 22 to 65 years old (median, 43.25 years). The sites of involvement included lymph node (2 cases), skin or soft tissue (1 case) and colon (1 case). The tumor cells were widespread infiltration, diffused distribution, no adhesion to each other. Tumor cells were middling and large, round, orbicular-ovate, polygon, epithelium appearance, plentiful cytoplasm and acidophilia, cystose. Nucelus was round, orbicular-ovate, dissymmetry. Nuclear chromatin was vacuole appearance, basophilia nucleolus, caryocinesia and pathological mitotic figure. Three of the cases showed conjugate nuclei, increased pleomorphism with multinucleated tumor giant cell formation. Focal cytoplasmic with foamy appearance was identified in 2 cases. One case demonstrated foci of spindly sarcomatoid appearance. Hemophagocytosis was identified in 2 cases. The tumor cells of 4 cases were often accompanied by various numbers of inflammatory cells. Immunohistochemical study showed that all cases were diffusely positive for α-1-ACT, CD68, CDl63 and lysozyme. Three of 4 cases also expressed CD45, CD45RO. The electron microscope results of 4 cases showed that the tumor cells were plentiful cytoplasm and a few cytolysosome in the cytoplasm, and no birbeck cytorrhyctes, cell-cell junction and digitation. Amongst the 4 patients with follow-up information available, three died of the disease 6-13 months after diagnosis. One patient, whose lesion was localized at the skin and soft tissue, survived at the present time., Conclusion: HS was a scarce malignant tumor with mature histiocyte morphology and immunophenotype character. The diagnosis should be based on tissue morphology, immunohistochemistry and electron microscope observation to exclude other disorders.

Objective: To explore the distribution and factors associated with female infertility in 3 areas in Xinjiang Uygur Autonomous Region so as to provide rationales for the prevention, diagnosis and treatment of infertility., Methods: A total of 1895 women of reproductive age were enrolled with a cluster random stratified sampling method. A questionnaire survey and pelvic examinations were conducted. The collected data were statistically analyzed., Results: The prevalence of infertility in these three areas ranged from 7.5% (76/1014) to 26.2% (144/550) with an average of 15.2% (279/1835). The prevalence of infertility was the highest in Shan shan and it was related with its unique geographical environment and life style. The lower levels of education and income, the higher prevalence of infertility. The occurrence of infertility was also correlated with their residence, premarital sex, body mass index and some concurrent diseases., Conclusion: It is necessary to carry out further studies on healthful life styles and those factors associated with the morbidity of infertility. The prevalence of infertility may be reduced and local reproductive health improved by avoiding or reducing the adolescent premarital sex and unmarried abortion.

Objective: To study the clinical pathological characteristics and high risk factors for borderline ovarian tumor (BOT) and stage I epithelial ovarian cancer (EOC)., Methods: A total of 91 patients with BOT and 52 patients with stage IEOC who were diagnosed and treated in the Department of Gynecology, Peking University People's Hospital from November 2002 to May 2010 were recruited in this study. The patients' clinical characteristics were reviewed respectively and compared between the two groups., Results: The women in BOT group were significantly younger than those in EOC group (41.16 ± 14.95 vs. 50.90 ± 14.37,P<0.01). Compared with women with BOT, women with EOC were more likely to be post-menopausal(42.3% vs. 23.1%,P=0.016) and more with family history of malignant tumors (26.9% vs. 13.2%,P=0.04).There were no significant differences in the size of tumors and the serum level of tumor markers. But the size of solid portion of the tumor of EOC was significantly larger than that of BOT(P<0.01). The extent of the increase of CP2 among the patients with EOC was higher than that among the patients with BOT(256.99 vs. 116.59, P=0.028). There was a statistically significant difference between the two groups in tumors' histopathological type(P<0.01). The serous and mucous tumors were more common in EOC group (90.1%, 82/91). In contrary, endometrioid, clear cells and mixed epithelial cancers were more common in EOC group than serous and mucous cancers (44.2%, 23/52)., Conclusion: Although the clinical presentation of patients with stage I EOC was similar to that of those with BOT, there were significant differences in the patients' age, post-menopausal or not, family history of malignant tumors, size of solid portion of tumors, extent of the increase of the tumor biomarker, especially of CP2 and tumors histopathological type. These clinicopathological characteristics might be helpful for us to make different diagnosis.

Objective: To investigate the effect and the molecular mechanism of insulin-like growth factor 1 (IGF-1) on the level of tau protein phosphorylation in PC12 cells induced by aggregated beta-amyloid protein(1-40) (Abeta(1-40))., Methods: MTT assay was used to measure the survival rate of PC12 cells, Western blot was applied to detect tau phosphorylation level, total tau, glycogen synthase kinase-3beta (GSK-3beta), and phosphorylation of GSK-3beta Ser9 for observing the effect of IGF-1 or LiCl, a specific inhibitor of GSK-3beta, on Abeta-induced tau protein phosphorylation in PC12 cells., Results: Different concentrations of IGF-1 could improve the survival rate of PC12 cells compared with that of Abeta(1-40) group (P < 0.05), and the best protective effect was observed in 1 microg/mL IGF-1 group. The levels of tau protein phosphorylation in the sites of Ser396, Ser(199/202) and the amount of whole tau increased after 3 h exposure and reached the maximum level after 12 h exposure to Abeta(1-40), meanwhile, the expressions of the amount of whole GSK-3beta was also increased (P < 0.05), but a decreased phosphorylation of GSK-3betaSer9 was observed (P < 0.05). Pretreatment with several dose of IGF-1 or LiCl, markedly reduced Abeta(1-40)-induced tau hyperphosphorylation and the expression of GSK-3beta (P < 0.05), but the expression of phosphorylation of GSK-3betaSer9 was increased (P < 0.05)., Conclusion: The levels of tau protein phosphorylation in the sites of Ser396, Ser(199/202) and the amount of whole tau increased by Abeta(1-40) in PC12 cells, GSK-3beta activation by Abeta(1-40) may lead to extensive tau phosphorylation. IGF-1 could attenuate Abeta(1-40)-induced tau protein hyperphosphorylation by inhibiting the activation of GSK-3beta.

Objective: To investigate the changes in the content of plasma matrix metallo proteinase-9 (MMP-9) in patients with acute cerebral infarction before and after thrombolytic therapy and its clinical significance., Methods: The levels of MMP-9 were determined in 34 patients with acute cerebral infarction before and after thrombolytic therapy, and 34 healthy individuals served as healthy control., Results: Compared with the healthy controls, the levels of plasma MMP-9 before thrombolytic therapy were not significantly increased [(13.47±3.09) ng/L vs. (12.89±10.22) ng/L, P >0.05]. In contrast, MMP-9 values were significantly increased after thrombolytic therapy [(22.06±12.53) ng/L] compared with that in either before or healthy control group (both P<0.05). MMP-9 values were significantly higher in patients with hemorrhage after thrombolytic therapy (incidence rate was 26.5%, 9/34) compared with before treatment [(24.02±15.41) ng/L vs. (14.28±2.33) ng/L, P<0.05], and the values of MMP-9 were higher than those of patients without hemorrhage [(20.42±9.57) ng/L], but there was no statistically significant difference ( P >0.05). In patients with complete revascularization (revascularization rate was 58.8%, 20/34), MMP-9 level was markedly higher than before thrombolytic therapy after thrombolytic therapy [(19.26±7.94) ng/L vs. (13.63±3.02) ng/L, P<0.05], and the values of MMP-9 were higher than the no-revascularization patients [(18.97±4.23) ng/L], but there was no statistically significant difference ( P >0.05)., Conclusion: Thrombolytic therapy activated MMP-9, and MMP-9 increased the risk of hemorrhage after thrombolytic therapy, and it participated in the mechanisms of hemorrhagic tendency after thrombolysis.

Objective: To assess the diagnostic and therapeutic modality preferences of physician implementation of the Chinese Clinical Practice Guidelines for Benign Prostatic Hyperplasia (BPH) for geriatric BPH patients., Methods: This cross-sectional survey was conducted at 33 medical centers located in 11 different cities in China (4 in north; 7 in south). A total of 190 physicians were requested to record their preferences in diagnostic tests and treatment options for elderly BPH cases., Results: The physician response rate was 97.4%. Respondents generally selected those practices consistent with the guidelines, but their preferences for recommended tests varied. The use of medical history, ultrasonography and urinalysis was higher (> 90.0%) and that of uroflowmetry was lower (31.2%). In addition, the rate of use of recommended tests was higher among physicians in the north than those in the south. Drug therapy was the preferred treatment option. The proportion of drug treatment increased with the severity of symptoms in elder patients. In the south, the proportion of drug treatment in severe cases increased to 82.6% versus 61.9% in mild cases. In the north, the proportion of rug treatment in severe cases increased to 83.5% versus 54.6% in mild cases., Conclusion: This study provides insights into the physician preferences of diagnosis and treatment. The physicians generally comply with the BPH clinical practice guidelines. It may also serve as a practical reference for updating and improving the Chinese Clinical Practice Guidelines for BPH.

Objective: To explore the changes of expression of uncoupling protein 2 (UCP2) in pressure overload induced failure myocardium in rats., Methods: Male SD rats were randomized into 3 groups (n = 15 each): abdominal aorta constriction (AC) 20 weeks group (H20w group), sham operation group (SH20w group) and normal control group (N group). Twenty weeks later, myocardial function was evaluated by echocardiography and hemodynamic measurements. Mitochondria in ventricular tissue were isolated by centrifugation. Adenine nucleotide pools (ATP, ADP, AMP, PCr) in myocardium were measured by high performance liquid chromatography. The expression of UCP2 in mitochondria was detected by PT-PCR and Western blot analysis., Results: Myocardial function was significantly decreased 20 weeks post-AC compared to SH20w group and N group. Myocardial ATP, ADP, AMP and PCr contents were also significantly decreased in H20w group than the other 2 control groups. The expression of UCP2 in myocardial mitochondria was significantly increased in H20w group and negatively correlated with ATP contents (r = -0.929, P < 0.01)., Conclusions: The expression of UCP2 was upregulated in pressure overload induced failure heart and might be responsible for decreased myocardial adenine nucleotide and energy metabolism disturbance in this model.

Objective: To explore the metabolic remodeling and its correlative mechanisms in human failing heart by contrasting the content of substrate, the activity of correlative enzyme and the mRNA and protein expression of beta(3)-adrenoceptor and peroxisome proliferator-activate receptor alpha (PPARalpha)., Methods: Cardo ac tossie samples were talem from 20 patients with heart failure of valvular heart disease and undergoing valvuloplasty operation as well as 6 subjects being killed in accidents (as control). The levels of free fat acid (FFA) and the activity of succinate dehydrogenase (SDH), Na(+)-K(+)-ATPase and Ca(2+)-Mg(2+)-ATPase of the myocardial tissue were measured. Protein and mRNA expression of beta(3)-adrenergic receptor and peroxisome proliferator-activated receptor alpha (PPARalpha) in myocardial tissue were analyzed using reverse transcriptase-polymerase chain reaction and Western-blot respectively., Results: In the failing hearts, the contents of FA and expression of beta 3 adrenoceptor mRNA and protein were obviously higher than those in the control group, the activity of SDH, Na(+)-K(+)-ATPase, Ca(2+)-Mg(2+)-ATPase and expression of PPARalpha mRNA and protein were on the contrary., Conclusion: The human failing myocardium is characterized by metabolic remodeling and it maybe concerned with the upregulation of beta3 adrenoceptor and downregulation of PPARalpha.

Objective: To compare the curative effects and expenses of pleural drainage by using central venous catheter and of simple aspiration by thoracentesis in treatment of spontaneous pneumothorax., Methods: 46 patients with spontaneous pneumothorax were randomly divided into 2 equal groups: Group A, treated with pleural drainage by using central venous catheter, and Group B, treated with simple aspiration by thoracentesis. The curative rate and average residual volume after treatment were used to evaluate the curative effects. The average hospitalization days, duration of treatment, and expenses for medical materials were used to evaluate as the economic index., Results: (1) The effective rates were 100% and 91.30% in Groups A and B respectively. (2) The average residual volume of pneumothorax at the time of discharge from hospital of Group A was 4.17%, significantly lower than that of Group B (18.62%, P < 0.05). (3) The average residual volume of pneumothorax 1 week after discharge of Group A was 0.53%, significantly lower than that of Group B (7.59%, P < 0.01). (4) The expense for medical materials of Group A was 264.79 Yuan RMB, a little bit more than that of Group B (233.62 Yuan RMB). (5) The hospitalization time of Group A was 5.32 days, significantly shorter than that of Group B (7.68 days, P < 0.05). The duration of treatment with antibiotics of Group A was 3.46 days, significantly shorter than that of Group B (5.59 days, P < 0.05). The time of oxygen inhalation of Group A was 86.4 hours, significantly shorter than that of Group B (133.1 hours, P < 0.01)., Conclusion: With higher curative effect and lower expenses, pleural drainage by using central venous catheter is superior to simple aspiration in treatment of spontaneous pneumothorax, and can be the first choice.

Objective: To explore the changes on the content of substrate, the activity of correlative enzyme and the mRNA and protein expressions of beta(3)-adrenoceptor and peroxisome proliferator-activated receptor alpha (PPARalpha) in human failing heart., Method: Papillary muscles from 20 patients with heart failure during mitral valves replacement and 6 control subjects died of non-cardiac accidents were obtained and free fat acid (FFA), lactic acid (LD) and the activity of Na(+)K(+)-ATPase and Ca(2+)Mg(2+)-ATPase, protein and mRNA expressions of beta(3)-adrenergic receptor and PPARalpha were measured., Result: In the failing heart, the contents of fat acid, LD and expression of beta(3)-adrenoceptor mRNA and protein were significantly higher while the activity of Na(+)K(+)-ATPase and Ca(2+)Mg(2+)-ATPase, expressions of PPARalpha at mRNA and protein levels were significantly lower than those in control myocardium., Conclusion: Metabolic remodeling (upregulation of beta(3)-adrenoceptor and downregulation of PPARalpha) might contribute to the pathophysiology of heart failure.

Noise of ECP (external counterpulsation) comes from the frequent movement of the electromagnetic valve iron core hitting the top of the valve body and the orifice of the bottom, and the high pressure and large air stream rubbing the orifice. This article studies the method to reduce mechanical noise of the electromagnetic valve core, that is to reduce the above movement energy and the hitting force. The method is used in ECP devices with grafying results. This noise controlling technology may reduce the noise of the electromagnetic valve from higher than 50dB to less than 25dB.

Objective: To compare the thresholds of auditory brainstem response (ABR)and auditory steady-state responses (ASSR) in the same group of deaf children and give a clinical evaluation for ASSR after that., Method: Both kinds of thresholds have been recorded and analyzed of these deaf children., Result: The ABR thresholds are (85.82 +/- 12.39) and (82.70 +/- 14.93) dB nHL for left and right ears. At four testing frequencies of ASSR, the thresholds are (86.91 +/- 16.70), (90.32 +/- 16.11), (91.02 +/- 16.58), (89.80 +/- 17.08) and (85.15 +/- 18.16), (89.32 +/- 17.76), (90.41 +/- 18.87), (85.15 +/- 17.03) dB HL for left and right ears. The correlation coefficients between the ASSR and ABR of left and right ears are 0.622, 0.721, 0.757, 0.714 and 0.613, 0.732, 0.795, 0.739 at these frequencies respectively. These results showed significant correlation exiting., Conclusion: Reliable and frequency specific results could be obtained by ASSR so that it could be as a promising audiometry in clinic.

Objective: To investigate the characteristics of coronary lesions in patients after first myocardial infarction (MI)., Methods: From May 1998 to December 2000, coronary angiography was performed on 878 consecutive cases who had had first MI within 6 months and without history of previous coronary revascularization, 481 with anterior-lateral MI, 368 with inferior-posterior MI, 19 with posterio-lateral MI, and 10 with location-undetermined MI, and 394 receiving thrombolytic therapy 176 (44.7%) of which were treated successfully, and 525 (59.8%) with history of pre-infarction angina pectoris and 428 (48.7%) with history of post-infarction angina pectoris., Results: (1) Normal coronary vessels or lesions less than 50% stenosis were seen only in 5.9% (52) of the patients. One-, two- and three-vessel diseases were present in 32.8% (288), 26.4% (232) and 34.9% (306) patients respectively. 3.2% (28) had concomitant left main stem (LMS) disease. Three-vessel coronary disease was significantly more common in the patients with a history of pre-infarction angina in comparison with those without such history (39.2% vs 28.3%, P < 0.01), and was significantly more common in the patients who did not undergo thrombolytic therapy in comparison with those who had received thrombolytic therapy (38.4% vs 30.5%, P < 0.05). (2) Only in 5.1% (41) cases the infarct-related artery (IRA) was normal or with lesions less than 50% stenosis. Total occlusion (100% stenosis), subtotal occlusion (95% to 99% stenosis), severe stenosis (70% to 94% stenosis) and borderline stenosis (50% to 69% stenosis) of IRA were seen in 29.6% (240), 22.6% (183), 37.9% (307) and 4.9% (40) of the cases respectively. Total occlusion of IRA occurred significantly less often in the thrombolytic group than in the non-thrombolytic group (24.6% vs 33.7%, P < 0.01). IRA could not be determined in 67 cases. (3) 90.5% (795), 79.4% (697), 57.2% (502) and 35.6% (313) of the patients had > or = 70% stenosis, > or = 90% stenosis, > or = 95% stenosis and total occlusion coronary lesions in at least one major coronary artery respectively, and coronary revascularization including PCI and CABG was needed on 84% (736/878) of the patients., Conclusion: Patients with a first MI usually have multi-vessel disease and severe coronary stenosis, with IRA having severe stenotic lesions. Revascularization treatment is needed in the majority of the patients. It is true too for the MI patients without history of pre- or post-infarction angina pectoris and those with successful thrombolytic therapy. Coronary angiography should routinely be performed on the patients who need further coronary revascularization.

Objective: To obtain the residual hearing by using multi-frequency steady-state response test in a group of deaf children and to compare the results with that of ABR., Method: Both sides of ears of 278 deaf children had been tested while they were asleep., Result: Positive incidences of MFSSR at 0.5, 1, 2, 4 kHz are 33.09%, 70.50%, 44.96%, 19.42% (left ears) and 33.81%, 66.91%, 41.07%, 17.63% (right ears) respectively. Except 4 kHz, the ratios at the other three frequencies are significant higher than that of ABR., Conclusion: MFSSR is a promising objective audiometry, this kind of test could provide frequency-specific information for hearing diagnosis.

Field insect population survey indicated that the principal natural predation enemies of cotton bollworm (Helicoverpa armigera Hubner) were Eringonidium graminicola Sundevall, Adonia variegata Goeze, Nabis sinoferus Hsiao. The results from experiments showed that the amount of prey consumed of these principal natural enemies increased when the density of prey rised, and decreased when the density of natural enemies increased. The predation function response fitted Holling's predation response equation II, and could be fit with the Disk Equation.