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Electron spin resonance spectroscopy(ESR) was used to investigate the effects of hydrogen ion concentration and hydroxide concentration in perchloric acid system and sodium hydroxide system on the state and behavior of free radicals generated by hydrazine bond breaking catalyzed by catalysts. The difference of free radicals generated by Pt/SiO2 catalyzed hydrazine decomposition in acid-base system was determined. The results show that in the alkaline system, with the increase of hydroxide concentration, the N-H bond breaking rate increases significantly, and the hydrolysis reaction is the main decomposition reaction. In acidic systems, with the increase of hydrogen ion concentration in the pH range from 6.9 to 1.1, the N-N bond breaking rate increases rapidly and is much higher than the N-H bond breaking rate. In the range of pH

A kind of nitrile rubber (NBR) with high bound acrylonitrile content was prepared by low-temperature emulsion-polymerization and the sequence structure of the polymer was characterized by proton nuclear magnetic resonance spectroscopy, and the effects of different coagulants on the coagulation behavior and physico-mechanical properties of the polymer were studied. The results showed that the BAA sequence structure appeared in NBR with high bound acrylonitrile content, and the content of BAA, BAB, and ABA sequence structures increased gradually and that of BBB and BBA sequence structures decreased gradually with the increase in bound acrylonitrile content; the coagulation efficiency of CaCl2 and Al2(SO4)3 was much higher than those of NaCl and H2SO4, and the coagulation efficiency of the first two both reached about 98%; Al2(SO4)3 could improve the hardness, tensile strength, modulus, and elongation at break of NBR, and the elongation at break of NBR prepared from Al2(SO4)3 was 566%.

H2C2O4 is widely used in spent fuel reprocessing. For example, in order to recovery plutonium oxalate precipitated mother liquor before returning, it is necessary to reduce the H2C2O4 concentration from 0.1 mol/L to about 10-4 mol/L. Among the methods of H2C2O4 destroyed in waste liquid, the process of H2C2O4 oxidized in nitric acid solution with Mn2+ as a catalyst is the most mature and suitable for industrialization, and its research is very rich. Nitrite plays an important role in destroying oxalic process in the process of H2C2O4 destroyed with Mn2+ as a catalyst in nitric acid solution was mentioned in many past studies. However, the specific reaction chain is still ambiguous and controversial on nitrite oxidation of H2C2O4 with Mn2+ as a catalyst, and the catalytic reaction mechanism is not clear. To solve these issues in the area of post-processing, the optimization of the treatment of the mother liquor of plutonium oxalate precipitation in the Purex process and the acquisition of H2C2O4 deep destruction technology in spent fuel reprocessing are to be benefited. Firstly, sodium nitrite solutions were continuously added into reaction solutions, at the same time the concentration of H2C2O4 in solutions was determined. H2C2O4 is obviously oxidized in the presence of nitrite and Mn2+ in sulfuric acid solutions. Secondly, Mn(Ⅱ) complexed oxalate oxidized to Mn(Ⅲ) with nitrous acid as a oxidant was studied. The results demonstrate that the complexation of Mn2+ with H2C2O4 reduces the reaction activation energy of Mn(Ⅱ) oxidized to Mn(Ⅲ), and MnC2O4 can be oxidized to ［Mn(C2O4)3］3- by nitrous acid. Finally, free radicals and substates in reaction process were detected by EPR’s spin capture technique. H2C2O4 is oxidized to ·OOC—COOH with the Mn(Ⅲ) complexed with itself, and Mn(Ⅲ) is reduced to Mn(Ⅱ). The ·OOC—COOH radicals with poor stability rapidly decompose and release reducing substances in acidic solution, and decomposition of H2C2O4 is completed. With the increase of acidity of nitrous acid, the concentration of HNO3 molecule increases. Thus, the concentration of HNO3 molecule in the solution can no longer be neglected compared with the concentration of nitrous acid. Therefore, when the concentration of nitric acid is more than 6 mol/L, the decomposition rate of H2C2O4 in the nitric acid solution with Mn2+ as a catalyst may be controlled by various reactions, which needs to be further studied.

In order to overcome the problem of multiple solutions and uncertainties in the identification of collapsed columns with a single seismic attribute and the problem of identification accuracy shift caused by unbalanced sample data, a binary classification collapsed column based on K-means SMOTE and random forest was constructed. The model can identify collapse columns by joint analysis of multiple seismic attributes. Taking the southern mining area of the east wing of the first mining area of Shanxi Xinyuan Coal Company as the research area, 12 seismic attributes extracted by the front interpreters through 3D seismic exploration technology are used as sample features, and the actually revealed collapse column information is used as sample labels to build a seismic multi-attribute attribute dataset; seismic attribute selection is carried out through correlation analysis, cluster analysis evaluation and random forest importance analysis, and 6 relatively independent seismic attributes are finally selected as sample features; the K-means SMOTE algorithm is used to balance the data set, and 8 992 data are obtained, of which 6 294 data are selected as the training set and 2 698 data are used as the test set; the random forest binary classification model is built based on the python language platform, and the final accuracy of predicting the collapsed column can reach 87%. By comparing three common machine learning classification algorithms, the model identified collapsed columns with higher accuracy.

Precious metal nanoclusters have unique electronic structure and fluorescent properties, and can be used as fluorescent probes in a wide range of applications such as biomarkers and ion detection. This paper reviews the preparation methods of thiol-protected silver clusters, including bottom-up and top-down methods, focusing on optimizing the reduction process of the reaction, selecting excellent thiol ligands, changing the pH values of the system, and strictly controlling. The research status of the preparation of thiol-protected silver clusters was introduced in terms of etching time and reaction temperature during the reaction, and ideas and suggestions for further research were provided. At the same time, based on the excellent fluorescence properties of thiol-protected silver clusters, the research progress in the detection of small molecules such as Cu2+, Hg2+, I- and cysteine was introduced. Finally, it was pointed out that the fluorescence quantum yield and safety of metal nanoclusters are improved, and the reaction mechanism of metal nanoclusters with heavy metal ions and biomacromolecules is studied in depth, and the synthesis methods of high purity and diversity alloy clusters or transition metal nanoclusters are explored. The preparation of fluorescent sensing materials for the realization of highly efficient thiol-protected silver clusters is a hot trend in future research.

The layered double hydroxides become research hot spot of oxygen evolution catalyzer for its easy preparation, feasible moderation of interlayer object,low cost and good stability but due to its low transmission speed of its electric charge,higher overpotential, so the modification is needed before mass application. The constructional character of the layered twinned material was firstly introduced, the catalytic mechanism of its oxygen evolution reaction was briefly described, then different kinds of optimization modification strategies to enhance its catalytic activity were introduced. The optimization modification strategies include:combination with conductive substrate, synthesis ultrathin nanometer plate, graphene compounding process, hybrid modification. The application of the stratified dihydride oxygen evolution catalyst in electrolysis of water to hydrogen and the advantages and disadvantages of different modification methods were put forward. The better-efficient oxygen evolution catalyst can be achieved through different kinds of modification. In the end, the difficulties in this kind of catalyzer were pointed out, including low recycle rate, catalyst stability, current density not meeting the requirements of industrialization and massive production.

Precious metal nanoclusters have unique electronic structure and fluorescent properties, and can be used as fluorescent probes in a wide range of applications such as biomarkers and ion detection. This paper reviews the preparation methods of thiol-protected silver clusters, including bottom-up and top-down methods, focusing on optimizing the reduction process of the reaction, selecting excellent thiol ligands, changing the pH values of the system, and strictly controlling. The research status of the preparation of thiol-protected silver clusters was introduced in terms of etching time and reaction temperature during the reaction, and ideas and suggestions for further research were provided. At the same time, based on the excellent fluorescence properties of thiol-protected silver clusters, the research progress in the detection of small molecules such as Cu2+, Hg2+, I- and cysteine was introduced. Finally, it was pointed out that the fluorescence quantum yield and safety of metal nanoclusters are improved, and the reaction mechanism of metal nanoclusters with heavy metal ions and biomacromolecules is studied in depth, and the synthesis methods of high purity and diversity alloy clusters or transition metal nanoclusters are explored. The preparation of fluorescent sensing materials for the realization of highly efficient thiol-protected silver clusters is a hot trend in future research.

Phycocyanin (PC) is a kind of natural pigment protein complex derived from marine algae. It is also a type of important food functional factor with anti-cancer, anti-inflammatory, and immune -enhancing activities, and has been widely used in functional food, medicine and cosmetics. Phycocyanin has been proven to inhibit the activity of non-small cell lung cancer (NSCLC) cells, but the underlying regulatory mechanism is not fully understood. This study focused on miR-642a-3p, and investigated the potential regulating mechanism of phycocyanin in NSCLC cells. The results showed that phycocyanin upregulated the expression level of miR-642a-3p in four NSCLC cells (A549, H1299, H460 and LTEP-a2). Overexpression of miR-642a-3p levels significantly inhibited the proliferation, migration and unanchored growth of four cells in vitro. In addition, transfection of miRNA inhibitors to interfere with the expression of miR-642a- 3p could enhance cell viability to a certain extent. This study preliminarily revealed that the up-regulation expression of miR-642a-3p was involved in the regulation of inhibiting NSCLC cell viabilities by phycocyanin, which could lay a sci¬entific theoretical basis for the in-depth study and utilization of phycocyanin. [ABSTRACT FROM AUTHOR]

Aiming at the problem of multi-objective reliability optimization for the reducer of road-rail vehicle,firstly,it must be ensured that the electric wheel planetary gear reducer is in good working order and loading conditions meet the requirements of transmission.By applying the reliability theory and optimization design technology,the reducer weight reduction,materials saving,low cost can be realized safety and reliability is improved.The MATLAB optimization toolbox is used to solve the problem of the optimization of reducer.Taking the volume and contact ratio as multi-objective optimization function,then the multi-objective optimization problem is transformed into single-objective problem to solve by the linear weighted method.The mathematical model is established by using the safety factor method and other constraints.By using Fmincon function,the optimizing calculation and analysis are carried out,the optimal solution is got,which makes the optimization design parameters more reasonable than the original design parameters.Consequently,the results show that the working performance of the electric wheel of the road-rail vehicle is improved.

BACKGROUND: Percutanoues pedicle screw internal fixation is widely used for treating lumbar disease. Because the surgery is guided by the C-arm, it is hard to control the position between screws and facet joint to cause the facet joint violation completely. Body mass index > 29.9 kg/m², facet joint angle > 35° and age < 65 years old are considered as the high risk factors for percutaneous pedicle screw injury of articular processes. Due to the different positional relationship between the pedicle axis of the lumbar spine and the articular process joint, there is no related report on whether the destruction of the articular process joint by screws is different. OBJECTIVE: To investigate the significance of lumbar CT multi-planar reconstruction for preestimating facet joint violation in lumbar percutaneous pedicle screw placement. METHODS: One hundred patients with lumbar fracture and degenerative disease who underwent percutaneous pedicle screw placement were selected. All patients signed the informed consents and the study was approved by the ethics committee of the hospital. The position line of the oblique axial view, oblique sagittal view and oblique coronal view was adjusted to reconstruct the section of pedicle. A circle with the 6.5 mm of position line of the oblique coronal view as its center to check the relationship between the circle and facet joint served as preoperation group. CT examination was performed after surgery for evaluating the degree of facet joint violation by screws and served as postoperation group. The amount of screws which damage the facet joint of different vertebrae between two groups and the damage rate among vertebrae in each group were compared. RESULTS AND CONCLUSION: (1) Totally 478 screws were placed, 109 (22.8%) screws violated facet joints in the preoperation group, and the amount of circles which violated facet joint was 6 (6.8%), 9 (10.5%), 19 (18.3%), 30 (30.0%), and 45 (45.0%) from L1-L5. (2) 115 (24.1%) screws violated facet joints in the postoperation group, the amount of circles which violated facet joint was 10 (11.4%), 7 (8.1%), 15 (14.4%), 26 (26.0%) and 41 (41.0%) from L1-L5. (3) The P values of McNamara test of different vertebrae were 0.08 (L5), 0.22 (L3), 0.20 (L3), 0.05 (U) and 0.08 (U). There was no significant difference between two groups. (4) The results of Kappa test were 0.67 (L1), 0.80 (L2), 0.80 (L3), 0.87 (U) and 0.92 (L5). The damage rate among vertebrae in each group had significant differences (P=0.000). (5) To conclude, the relationship between percutanoues pedicle screw and facet joint could be recognized by lumbar CT multiple level reconstruction, which provides a reliable method for preestimating the possibility of facet joint damage caused by the percutanoues pedicle screw. [ABSTRACT FROM AUTHOR]

A precise solar model is the key of digital simulation and optimal design for the maximum power point tracking system. For simplified four-parameter PV model ( Iph, Io, Rs, C), the open circuit equation, short circuit equation and peak equation were analyzed, and the resistance incremental equation was given. Combined with four standard electrical parameters ( Isc, Voc, Im, Vm ) provided by manufacturers to get the simplified model's parameters, the resistance increment PV model was established, the photovoltaic cells dynamic model which varies with irradiance and temperature was presented, and the maximumpower- point dynamic model was proposed. Comparative study shows that the new model is a simpler structure and a higher accuracy than conventional model. Simulation and experimental results verify the correctness and feasibility of resistance incremental PV model; it can be used as a universal PV model in theoretical analysis and engineering design. [ABSTRACT FROM AUTHOR]

PURPOSE: To observe and investigate the facial profiles and functional recovery in patients with CAD/CAM obturator prosthesis after total maxillectomy for malignant tumor. METHODS: Eighteen patients with T3 -4a NOMO maxillary malignant neoplasm were treated by total maxillectomy and immediate CAD/CAM obturator prostheses repair. The patients were followed up and underwent examinations at 1 -, 3 - and 6 -month after surgery. The facial features, pronunciation clarity, deglutition and mastication were evaluated in the patients with and without CAD/CAM prosthesis simultaneously or permanently. SPSS 13.0 software package was used for statistical analysis. RESULTS: Postoperative follow-up showed that there were significant differences in pronunciation clarity (τ=29.38, 136.24, respectively, P<0.05), mid-facial region collapse (τ =2.73, 4.74, 5.92, respectively, P<0.05), and eyeball sagging (τ =8.20, 15.17, 14.74, respectively, P <0.05) between patients with and without CAD/CAM prosthesis. Swallowing ability was significantly improved from Class IV to Class II. The average score was 23 in the questionnaires regarding to chewing ability, indicating patients could chew hard and ordinary food. Thirteen patients wore the permanent prothesis at 6-month after surgery with clearer pronunciation (τ = 102.34, P<0.05). CONCLUSION: Repair of maxillofacial defect with immediate CAD/CAM prosthesis after maxillectomy can preserve the facial features and improve the quality of life. The postoperative maxillary space can be directly observed during follow-up. This treatment modality is one of the preferred options in patients with maxillary malignant tumor after total maxillectomy. [ABSTRACT FROM AUTHOR]

According to the theory of five movements and six climates, the innate constitution plays a crucial role in determining the underlyingpa thological mechanisms of diseases later in life. Previous studies have demonstrated a close association between the constitution, as defined by the theory of five movements and six climates, and the development of various types of tumors. Furt hermore,the tumorsubtype determined by the constitution has prognostic implications. This highlights the potential of utilizing the fivemovements and six climates theory to guide the implementation of precision medicine strategies in thefield of oncology. However, no resear ch has yet been conducted to investigate the use of this theory in guiding the development of tumor molecular classification and precisi onmedicine strategies. The objective of this research is to uncover the biological characteristics of each constitution within a pancanc ercohort and identify potential anti-tumor drugs that are applicable to patients with different constitutional types. By doing so, we aimto c ontribute to the establishment of a precision medicine strategy for tumors derived from the original concepts of traditional Chi nesemedicine(TCM). In this study, we obtainedpan-cancer Bulk RNA-Seq data from UCSC Xena, GWAS cohort data from the UKBiobank, and cis-eQTLs data from eQ TLGen and GTEx V8. We employed machine learning methods to screen for hub genes associated with each constitution. Subsequently, we utilized informatics tools to explore the biological characteristics of each constitut iondefined by the theory of five movements and six bioclimates. Further, potential anti-tumor drugs suitable for patients with differen tconstitutional types were identified through mendelian randomization, molecular docking, and drug-like prediction techniques. Withinthe pan-cancer cohort, significant differences were observed among different constitutions in terms of progression-free interval, biological f unctions, immune cell abundance, tumor drug sensitivity, and immunotherapy response. These findings suggest that the five movements and six climates theory can guide tumor molecular classification and the development of precision medicine strategies. Moreover,the biological characteristics inherent to each constitution partially shed light on the scientific implications of Chinese medicinetheories, offering a fresh perspective towards clinical cancer treatment. Through molecular docking and drug-like prediction, several po tential anti-tumor drugs such as 17-beta-estradiol, serotonin, trans-resveratrol, and linoleic acid were identified. Overall, the util izationof multi-omics approaches pro vides a powerful tool to unravel the scientific foundations of TCM theories. The elucidation of themu lti-omics features associated witheach constitution in tumors serves as the basis for applying the five movements and six climates theoryto tumor molecular classification and the development of precision medicine strategies.

Objective: To establish a model of reproductive system injury in male rats at high altitude using the low-pressure hypoxic animal laboratory and study the changes in the testicular tissue, semen parameters, blood gas and oxidative stress in male rats at different altitudes., Methods: Sixty male Wistar rats were randomly assigned to be raised on the plains (the plains group, n = 20), at an altitude of 4 000 m (the plateau model group Ⅰ, n = 20), or at an altitude of 6 000 m (the plateau model group Ⅱ, n = 20) for a spermatogenic cycle of 14 days. After establishment of the model of high-altitude reproductive system injury, the testis tissues of the rats were harvested for HE staining and observed for histopathological changes under the light microscope, and their epididymedes collected for preparation of sperm suspension and detection of sperm motility, sperm count and the percentage of morphologically abnormal sperm (MAS). The blood gas level and oxidative stress-related indexes in different groups were also measured using the serological test., Results: With the elevation of altitude, the levels of pH and PO2 were decreased, those of PCO2, Hct, K+, Cl－ and Hb increased markedly, while that of Na+ exhibited no significant change. The model rats also showed folded spermatogenic tubule walls, thinned spermatogenic epithelia, disorderly arranged and reduced number of spermatogenic cells, and increased vascuolization in the spermatogenic epithelia, with decreased sperm motility and count, increased percentage of MAS, elevated concentration of malondialdehyde (MDA) and reduced activity of superoxide dismutase (SOD)., Conclusions: A model of reproductive system injury was successfully established in male rats at a simulated altitude of 4 000 m. With increasing of the altitude to 6000 m, oxidative damage to the testicular tissue was aggravated, sperm motility decreased, and the percentage of MAS increased, indicating that an altitude of 6 000 m may cause serious damage to the rat reproductive system.

Objective: To investigate the correlation between the lumbar bone marrow fat and abdominal fat., Methods: A total of 68 individuals (32 men and 36 women, aged 21-74 years with a median of 49.5 years) were included in this study. All the subjects underwent spectroscopic examination of the third lumber vertebra with the single voxel method on a 1.5T MR scanner to measure the fat fraction (FF%). Quantitative CT was also performed for measurement of the abdomen subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT). The measurements were compared between subjects aged ≥50 years and those below 50 years, respectively,in male or female subjects., Results: In male subjects, BMI, FF%, VAT or SAT showed no significant differences between the two age groups (P>0.05), and FF% was not correlated with BMI, VAT or SAT (r=0.109, 0.034, 0.066, respectively; P>0.05). In the female subjects, BMI, FF%, VAT and SAT differed significantly between the two age groups (P<0.05), and in ≥50 years group, FF% showed a positive correlation with VAT (r=0.499, P<0.05) but was not correlated with SAT (r=0.221, P>0.05); in<50 years group, FF% was not correlated with VAT or SAT (r=0.076, -0.067, respectively; P>0.05)., Conclusion: FF% is positively correlated with VAT in female subjects aged beyond 50 years, but is not correlated with VAT or SAT in male subjects or in younger female subjects.

Objective: To investigate the correlation between the lumbar vertebra bone mineral density (BMD) and age, gender, height, weight, body mass index, waistline, hipline, bone marrow and abdomen fat, and to explore the key factor affecting the BMD., Methods: A total of 72 cases were randomly recruited. All the subjects underwent a spectroscopic examination of the third lumber vertebra with single-voxel method in 1.5T MR. Lipid fractions (FF%) were measured. Quantitative CT were also performed to get the BMD of L3 and the corresponding abdomen subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT). The statistical analysis were performed by SPSS 19.0., Results: Multiple linear regression showed except the age and FF% showed significant difference (P<0.05) , the gender, height, weight, BMI, waistline, hipline, SAT and VAT showed no significant difference (P>0.05). The correlation of age and FF% with BMD was statistically negatively significant (r=-0.830, -0.521, P<0.05). The ROC curve analysis showed that the sensitivety and specificity of predicting osteoporosis were 81.8% and 86.9%, with a threshold of 58.5 years old. And it showed that the sensitivety and specificity of predicting osteoporosis were 90.9% and 55.7%, with a threshold of 52.8% for FF%., Conclusion: The lumbar vertebra BMD was significantly and negatively correlated with age and bone marrow FF%, but it was not significantly correlated with gender, height, weight, BMI, waistline, hipline, SAT and VAT. And age was the critical factor.

Objective: To analyze the imaging abnormal findings of ankle injuries in professional soccer player of males., Methods: The thirty-two professional soccer players in local region soccer club had been selected as research objects from March 2014 to January 2015, and all were men. Average age was 22.03±3.0 years old (19-33 years); the average age was 8.6±2.0 years old that began to engage in professional football training, and average time of engaged in football sports was 13±4 years (7-27 years). X-ray examination was used VM DR (Philips Co.), anteroposterior and lateral position of ankle joints. CT scan was used MSCT of 64 rows detector (Aquilion 64, TOSHIBA Co.). After routine scan, raw data was transmitted to the workstation and then reconstructed to be axial, sagittal, coronal imaging. MR examination was used 1.5 T superconducting equipment system (Achieva Dual, Philips Co.) and with ankle joint special phased array coil. TSE sequence be used to scan routine axial T2-weighted imaging; coronal T1-weighted imaging; coronal PWI; and sagittal T2-weighted imaging with fat suppressed. The sagittal PWI scan was used with Isotropic with fat suppressed FFE sequence., Results: The X-ray examination was finished for 28 person and 51 ankle joints. 26 person and 52 ankle joints were completed CT scan and reconstructed imaging for all joints. MR examination was finished in 30 person and 51 ankle joints. On X-ray and CT display that the abnormal changes of the talus is most commonly found that the incidence of "dolphin mouth" like protrusion at posterior edge was 35 ankles (rate of occurrence was 68.6%), the triangle prominence at out edge was 45 ankles (rate of occurrence was 88.2%). It also was found that 8 lateral malleolus have osteophytes, 5 ankles have medial malleolus osteophytes and 12 ankles have loose bodies at posterior ankle. MRI showed that 30 ankles were the anterior talofibular ligaments injury and incidence was 58.82%, 26 ankles were posterior talofibular ligaments injury (incidence was 51.0%), 25 ankles were calcanofibular ligaments injury (incidence was 49.0%), 29 ankles was the synovitis and local effusion at posterior ankle (incidence was 56.9%), the partial ligaments injured of deltoid ligaments were usually found and entirely torn were very rare (only three ankles). The former groups and shallow ligaments of deltoid ligaments were prone to injury. The common tendon disease of injury was tenosynovitis, 18 flexor hallucis longus tenosynovitis, 13 posterior tibialis tenosynovitis,7 flexor digitorium tenosynovitis, 5 peroneus longus tenosynovitis, 2 peroneus brevis tenosynovitis and 6 Achilles tendinopathy. Tendinosis and tendon degeneration was relatively rare., Conclusion: The professional soccer players have been easily lead to the anatomic abnormal and pathological changes in the bones, ligaments and tendons due to long-term training and competition. The majority changes were chronic injury. Imaging examination can be found the abnormal changes of ankle and could help athletes, coachs, doctors to understand and assess the ankle structure and functional status.

Objective: To analyze the clinical effect of Le Fort I osteotomy approach associated with endoscope for the resection of juvenile nasopharyngeal angiofibroma., Methods: Three patients with juvenile nasopharyngeal angiofibroma, stage II b, were retrospectively analyzed. All of them underwent Le Fort I osteotomy approach associated with endoscope between 2004 and 2009. All patients were followed up at first, third, sixth months and one year after surgery. Two years later, endoscopic examination and CT scan were performed, to analyze the clinical effect., Result: All three patients had total removal of tumor and no postoperative complications. No tumor recurrence was found 2 years after operation, and no face deformity. The tooth articulation was recovered, these patients could eat hard diet, although one patient had lose a little teeth sensation., Conclusion: Le Fort I osteotomy had good clinical effect, if associated with endoscope, it could get a good surgical exposure, and can do well in the treatment on juvenile nasopharyngeal angiofibroma, even intruded into pterygopalatine and infratemporal fossa.

Objective: The feasibility and clinical effects of hollow obturator prosthesis for the repair of maxillofacial defect immediately after maxillectomy for cancer were assessed., Methods: Thirteen patients with T3-4aN0M0 maxillary neoplasm were treated by the prostheses immediately after maxillectomy. According to the 3D-CT reconstruction of nasal sinus, the 3D stereoscopic prototype was constructed before the surgery. Simulating surgery with Surgicare 5.0 software and then the prosthesis 3D stereoscopic model was shaped. The prosthesis was made quickly and precisely with methacrylate resins according to the model and the print mold before surgery, with supplementary tooth at the bottom of prosthesis. In the surgery, the prosthesis was installed instantly after maxillectomy. The patients were followed up at 1, 3 and 6 month after the surgery, respectively. The facial features and the pronunciation clarity were examined and the questionnaires were carried out in the patients, with comparation by paired t-test. The hollow obturator prosthesis would be replaced by permanent prosthesis made of methacrylate resins at 6 month after the surgery., Results: The hollow obturator prostheses were installed accurately and maxillofacial defects were repaired immediately after maxillectomy in the 13 patients. Postoperative follow-up showed there were significant differences in eyeball sagging (t = 4.67, P < 0.05), mid-facial region collapse (t = 5.67, P < 0.05), and pronunciation clarity (t = 16.38, P < 0.05) between patients with and without prostheses. Questionnaires showed that all the patients were satisfied with the retention of prostheses, the improvement of appearance, the improvement of the symptom of water choking and speech definition. Six months after the surgery, the hollow obturator prostheses were replaced smoothly by permanent prostheses in 11 of the 13 patients., Conclusion: The precise and instant repair of maxillofacial defect by prosthesis after maxillectomy can improve survival quality of patient.

Objective: To study the significance of supratubal recess and its aeration pathway to epitympanum in the pathogenesis of cholesteatoma otitis media., Methods: Fifty-two ears of cholesteatoma were selected as study group. Sixteen ears of traumatic facial palsy with pneumatic mastoid, which had no history of chronic otitis media were selected as control group. The status of supratubal recesses of all and their aeration pathways to epitympanum were observed in operations., Results: Sixteen ears from control group clearly presented supratubal recesses. Membrane closure was founded in four of them. The aeration pathways of fifty-two ears (100%) from study group were all completely closed. Comparing with control group, the difference was obviously significant (chi2 = 41.7144, P = 0.000). Among these cases, bony closure was observed in thirty-four ears (65.4%), while membrane closure in eighteen ears (34.6%). Their epitympanum space was very narrow and mastoid was sclerotic or poorly developed., Conclusions: Blockage of the aeration pathway between supratubal recess and epitympanum was possible one of the origins of negative-pressure status of epitympanum and mastoid, which might lead to the formation of aural cholesteatoma. Anatomy variation of the aeration pathway from supratubal recess to epitympanum might be a pathogenesis factor of cholesteatoma otitis media. It suggested that opening the aeration pathway in tympanoplasty with intact canal wall up technique might be helpful to prevent recurrence of aural cholesteatoma.

Alpha-amylase are of considerable commercial value. It can be produced by a wide variety of microorganisma. The alpha-amylase gene (amyE) from Bacillus licheniformis, which is widely used for the industrial hydrolysis of starch, was mutated (amyEM), then amplified by PCR and inserted into pBV220 and pPIC9k to obtain the recombinant vector pBV220-amyEM and pPIC9k-amyEM. These recombinant vectors were transformed into corresponding competent cell E. coli DH5alpha and P. pastoris GS115 respectively. The resulting recombinant strains, DH5alpha/pBV220-amyEM and GS115/ pPIC9k-amyEM, were then screened by measuring the enzymatic activity and SDS-PAGE. DH5alpha/pBV220-amyEM was induced by temperature and GS115/pPIC9k-amyEM by methanol. In contrast to the parent cells, the a-amylases were expressed in both the recombinant strains. In E. coli the molecular weight was approximately 55kDa; optimal temperature and pH of the recombinant a-amylase were 80 degrees C - 90 degrees C and 6.0 respectively. The recombinant amylase had high activity in pH 5.0 - 5.5 compared to wild type. In Pichia pastoris, the recombinant amylase was secreted to the medium; molecular weight was 60kDa for the putative post-translational modifications; optimal pH shifted to 5.5. The specific activities of alpha-amylase produced by E. coli and P. pastoris were 8.1U/mg and 102U/mg respectively. This result indicated that the alpha-amylase were secreted into the culture medium with high efficiency in the recombinant P. pastoris High activity in high temperature and lower pH properties impart the recombinant amylase potential applications in industry.