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Polycrystal samples of La1-xSrxMnO3 (x=0.2, 0.3) have been synthesized using a sol-gel method. The effect of sintering process on the sample microstructure and Sr doping on the magnetoresistance for La1-xSrxMnO3 have been investigated. The results show that the increase of sintering temperature and time can promote the crystallization of samples and reduce the content of impurity. The additive of Sr makes Mn ion in materials relatively compact, and this causes the distorted deformation of the materials structure. The magnetoresistance (MR) changes with the Sr doping. When x=0.2, the maximum MR% of sample is about 43% and keep about 40% between 10~150K. At room temperature, the MR% will decrease to about 6.5%. When x=0.3, the order magnetoresistance (OMR) effect occures above the room temperature.

To summarize MA Shao-qun's clinical experience of warm moxibustion for the liver diseases. The warm moxibustion was put to use by MA Shao-qun to treat many diseases, including hepatitis, cirrhosis and liver functional disorder. Under the human-oriented theory, he focuses on regulating the whole function of the body and tonifying the original qi to increase physical fitness and avoid illness. Besides, he is good at the combination of multi-acupoints for long-term and circulating moxibustion treatment, and also pays attention to nourishing the spleen-stomach, adjusting the fu-qi and resolving the dampness in the body.

Various fonns of perforation plates were found in Knema furfuracea (Hook. f. et Th.) Warb.: scalariform perforation plates, reticulate perforation plates, intermediates between scalariform and reticulate, and other multiperforate plates. These plates were paired in various combinations. Scalariform perforation plates and pairs of such plates were predominant and the remaining plate pairs were of lower occurrence and irregularly distributed in the xylem. Their morphology is illustrated by SEM micrographs.

To investigate the effects of different fluid resuscitation regimes on lung injury and expression of pulmonary aquaporin 1 (AQP1) and AQP5 in rats with uncontrolled hemorrhagic shock.Sixty Sprague-Dawley (SD) rats were randomly assigned to the following five groups: control group (C group), no fluid resuscitation group (NF group), lactated Ringer's solution group (LRS group), 7.5%NaCl group (HS group) and hydroxyethyl starch group (hydroxyethyl starch 130/0.4, HES group). A four-phased uncontrolled hemorrhagic shock model was reproduced. Uncontrolled hemorrhagic shock phase began with blood withdrawal extended over 15 minutes, in which animals were subjected to massive hemorrhage [mean arterial pressure (MAP)=40 mm Hg (1 mm Hg=0.133 kPa)] for 60 minutes and followed by intratracheal lipopolysaccharide 2 mg/kg and continuous bleeding with amputation of the tail. Then, animals were partially resuscitated with LRS of 3 times the volume of shed blood (LRS group), followed by a bolus dose of 4 ml/kg body weight of 7.5%NaCl (HS), or hydroxyethyl starch (a volume equal to that of the shed blood), respectively, during different fluid resuscitation regimes. After that, comprehensive resuscitation phase of 60 minutes began with hemostasis, and transfusion of all the shed blood plus same amount of normal saline. Observation phase was continued for 3.5 hours. At the end the experiment, the lung tissue was sampled to measure wet-to-dry lung weight ratio (W/D), and the expression of AQP1 and AQP5 were determined with immunohistochemistry. The paraffin-embedded lungs were stained with hematoxylin and eosin for pathological analysis.When compared with NF and LRS groups, the lung W/D ratio was significantly decreased, and the shock induced decreased expression of AQP1 and AQP5 in lung tissue were attenuated in HES group, but these beneficial effects were blunted in the HS group.Uncontrolled hemorrhagic shock may induce lung injury and pulmonary edema as well as down regulation of the expression of AQP1 and AQP5 in rats. Resuscitation with hypertonic fluids, especially with HES, can reduce lung damage and pulmonary edema in this kind of shock. The cause may be due in part to maintenance of the expression of AQP1 and/or AQP5 in the lung. Pulmonary AQP1 and AQP5 play an important role in fluid transportation.

To investigate the changes in pulmonary transforming growth factor-beta1 (TGF-beta1)/smad2 signaling pathway in pulmonary injury as a result of hemorrhagic shock followed by lipopolysaccharide challenge.Twenty-four Sprague-Dawley (SD) rats were randomly assigned to the following two groups: sham operation group (sham group, surgery, no hemorrhage and no resuscitation), and two-hit model group (HS group), each n=12. Three-phased uncontrolled hemorrhagic shock model was reproduced in rats. Hemorrhagic shock phase I began with blood withdrawal over 15 minutes, i.e. animals were subjected to massive hemorrhage [mean arterial pressure (MAP)=35-40 mm Hg (1 mm Hg=0.133 kPa) for 60 minutes], followed by intratracheal lipopolysaccharide 2 mg/kg (two-hit model). Ninety minutes after blood shedding, resuscitation phase II of 60 minutes began with hemostasis, return of all the blood initially shed, plus fluids. Observation phase III was 210 minutes. After phase III, blood gas analysis with carotid artery blood was performed. Lung tissue was sampled to measure values of wet-to-dry lung weight (W/D) ratio and pulmonary microvascular permeability. Immunohistochemistry and reverse transcriptase polymerase chain reaction (RT-PCR) were used to assess the expression of TGF-beta1 protein and mRNA, and the protein content of the smad2 was determined by Western blotting.Compared with sham group, MAP was significantly lowered after 60 minutes in phase I, and lactic acid content was increased significantly, while partial pressure of oxygen in artery (PaO2), blood pH, HCO(-)3, arterial oxygen saturation (SaO2) and negative base excess (BE) showed a significant decrease in HS group. Concomitantly, values of pulmonary microvascular permeability and W/D ratio were significantly increased in HS group (all P0.01). In sham group, weak TGF-beta1 staining was detected in the alveolar epithelial cells. However, intense positive immunostaining for TGF-beta1 was observed in alveolar epithelial cells, pulmonary interstitial inflammatory cell as well as macrophage cells of alveolar space of the HS group. Lung tissue in HS group demonstrated a marked increase in TGF-beta1 mRNA and smad2 protein expression in the lung tissue compared with those of sham group (all P0.01).The expression of TGF-beta1/smad2 signaling pathway may play an important role in regulation of pulmonary permeability and development of pulmonary edema in acute lung injury induced by uncontrolled hemorrhagic shock followed by lipopolysaccharide challenge.

Color vision is a major component of vision function. Examination of color vision mostly relies on subjectivity at present. It is important to establish an objective method of color vision examination that would have particular clinical significance and forensic medicine value. With the development of new technology, the examination of visual electrophysiology has become a basic method of clinical diagnosis and investigation. Electroretinogram (ERG) could discriminate different cone cells and color abnormality. Visual evoked potential (VEP) generated characteristic negative wave after stimulation with different colors. Different visual electrophysiology detection methods were reviewed and in particular important new advancement of color vision research of ERG, F-VEP and P-VEP were introduced. The application prospect of color vision research in the clinical forensic medicine was also discussed. It is likely that color vision research study and visual electrophysiology will provide objective evaluation of retina and brain function.

To study the diagnostic value of CT/HRCT for the coal workers' pneumoconiosis (CWP) with large opacities.Sixty-two patients with CWP were examined with both chest radiograph and CT/HRCT scan. Comparison was done.Large opacities were found in 19 patients in the chest radiograph of 62 patients with CWP. The detection rate was 30.6%. Thirty large opacities were found using chest radiograph. Forty-three patients with large opacities were found using the CT/HRCT. The detection rate was 69.4%. One hundred and twenty-three large opacities were found using CT/HRCT. Ninety-three more large opacities were found by CT/HRCT than by chest radiograph. The total detection rate of large opacities by CT was 4.1 times than by chest radiograph. Both differences were statistically significant (chi2 = 18.58, P0.01). CT/HRCT found all patients with large opacities detected in the chest radiograph. Seventeen patients with Stage III large opacities (or= 1.0 cm x 2.0 cm) were found by the chest radiograph. The detection rate was 27.4% (17/62). Twenty-seven large opacities were found using chest radiograph. Thirty-four patients with Stage III large opacities were found using the CT/HRCT. The detection rate was 54.8%. The found Stage III large opacities added up to 67. The found Stage III large opacities by CT/HRCT were 40 more than using chest radiograph. Both differences were statistically significant (chi2 = 9.63, P0.01). CT/HRCT was reliable to show the morphology, the inside structure, the tiny lesion and the special location of the large opacities of CWP. It could provide more important information for differential diagnosis.CT/HRCT is significantly better than the chest radiograph in the diagnosis of complicated CWP. It can find the large opacities that the chest radiograph can not. It has a great diagnostic and practical value as an assistant examination method. CT/HRCT could be considered as the reference and evidence for staging progression in diagnosis of pneumoconiosis.

To determine the lung protection of continuous pulmonary artery perfusion with oxygenated blood during cardiopulmonary bypass (CPB).Thirty patients undergoing mitral valve replacement were randomly divided into the control group (n=15) and the lung perfusion group (n=15). The patients in the lung perfusion group were perfused oxygenated blood continuously to the pulmonary artery during CPB. The patients in the control group were performed the routine procedure of mitral valve replacement. Record the CPB time, aortic cross-clamp time, mechanical ventilation time and ICU monitoring time. The patients' oxygen index (OI) and lung static compliance (Cstat) were measured before the surgery, at 0 h after the CPB and at 0, 6 h after the surgery. Right lung biopsy specimens were obtained at 30 min after the CPB to observe the histological changes. Results The mechanical ventilation time and ICU monitoring time were shorter in the lung perfusion group than those in the control group (P0.05). The patients' OI and Cstat were higher after surgery in the lung perfusion group than those in the control group (P0.05). Tissue examination showed lung parenchyma edema and inflammatory cells accumulated in the control group, while no remarkable pathological changes occurred in the lung perfusion group.Lung injury exists after the surgery by CPB. Continuous pulmonary artery perfusion with oxygenated blood during CPB can decrease the lung injury.

To explore the spatial distribution character of dengue fever and the change of Aedes' population, so as to provide macroscopical decision-making evidences of prevention and supervision on dengue fever.(1) Collecting data on morbidity of dengue and supervision on vector's population in the corresponding period. (2) Drawing digitized map of Chaozhou in scale of 1:50,000, including elements of boundary, residential areas, road and traffic, altitude, water systems etc. (3) Measuring the latitude and longitude of center position of surveillance safes on the scene. (4) Processing spatial analysis by the ArcGIS 8.5 software.Distribution of Aedes showed spatial cluster in Chaozhou, while its density was related to the distance to the watersides. The closer to the watersides, the higher the density was. Map on spatial distribution showed that although the Aedes epidemic situation changed yearly, but primarily be kept in high, middle, low regions. Cross-validation effects of the distribution maps were satisfactory.Geographic information system was promising in analyzing data on dengue fever, and better than other routine research methods.

A least square fitting algorithm for alignment of multi-open-curved segments and point pairs of anatomical features obtained from both portal images and simulation radiographs has been developed for patient position verification in radiation therapy. A coordinate system associated with each curved segment pair is constructed so that the discrepancies of each segment pair can be obtained easily. The algorithm allows users to select not only multiple curve pairs but also individual point pairs on the important anatomic landmarks. The misregistration is measured by the sum of the position deviation of individual point pairs and ordinate discrepancies of all segment pairs from their corresponding coordinate systems. A mathematical minimization method is applied to seek an optimal transformation for matching of all segment and/or point pairs involved. The reliability of the algorithm has been tested with both phantom and clinical images. The test results indicate that the typical errors are less than 1 mm and 1 degrees in translation and rotation, respectively.