It is very significant that state trains rural-oriented medical students for grassroots health institutions.In combination with the characteristics of Chongqing rural-oriented medical students,the article analyzed and explained the reasons of building autonomous-cooperative learning model,discussed the connotation and the correlation theory of this model.Based on the above,the article designed and carried out autonomous-cooperative learning model,summarized the construction strategy from the aspects of organization and management mechanism,competitive and encouraging mechanism and evaluation mechanism,which explored a practical education pattern that suits rural-oriented medical students.

BACKGROUND:Primary human lung epithelial cel s are difficult to be isolated and cultured in vitro, which is characterized as limited sources, low cel viability, slow proliferation capacity, and lacking of differentiation capability.
OBJECTIVE:To establish an air-liquid interface model of lung epithelium by in vitro proliferation of human bronchiolar epithelial cel s, which is used for research on function of lung epithelial cel s.
METHODS:Primary human bronchiolar epithelial cel s were isolated using Pronase and DNase I combined digestive methods, and then proliferated using medium containing ROCK kinase inhibitor. The proliferated cel s were used for establishment of the air-liquid interface epithelium model. Cel differentiation was identified using scanning electron microscope, phase contrast microscope and immunofluorescent staining.
RESULTS AND CONCLUSION:The primary human bronchiolar epithelial cel s could be expanded successful y using medium containing ROCK kinase inhibitor, and the basal cel marker Cytokeratin14 was preferential y expressed in the proliferated cel population, indicating that these basal cel s might be the main subpopulation of human lung epithelial stem cel s. Subsequently, the proliferated cel s under the air-liquid interface could differentiate into ciliated cel s and non-ciliated column cel s. The results suggest that the proliferation and differentiation of human bronchiolar epithelial cel s were maintained in the presence of ROCK kinase inhibitor, and the air-liquid interface could promote the differentiation of human bronchiolar epithelial cel s.

Objective To conduct a prospective phase Ⅱ clinical study to explore the distribution of CYP2D6 gene polymorphism in Chinese population and its relationship with the metabolism of tamoxifen in early-stage hormonal receptor-positive breast cancer. Methods CYP2D6 genotype was tested by Sanger sequencing using the ABI 3500 Genetic Analyzer. Plasma concentrations of tamoxifen and endoxifen were measured using the HPLC-MS/MS(API 2000)assay. We downloaded the data of CYP2D6 allele from the CPIP database. Results In Chi-nese patients,the most common alleles were CYP2D6*1,*2,and *10;the predominant diplotypes were *1/*10 (38.3%)and*10/*10(18.8%). The distribution of metabolic phenotype,plasma concentration of endoxifen,and endoxifen:tamoxifen plasma concentration ratio were inconsistent between the normal metabolic phenotype(EM) and the intermediate phenotype(IM)under different CYP2D6 activity prediction criteria.The differences in the ratios and endoxifen plasma concentrations were statistically significant between the three groups by cluster analysis. Conclusions The CYP2D6 genotype distribution in Chinese population is different from that in the Western popu-lation. There is considerable variation of serum endoxifen concentration in Chinese breast cancer patients possess-ing the phenotype previously known as the intermediate active metabolizers of CYP2D6. Therefore,in the current era of precision medicine,the standard CYP2D6 genotype-phenotype classification system cannot properly stratify the Chinese population with different levels of endoxifen plasma concentration.

Objective:To investigate the effect of total saponins of Panax notoginseng (TSPN) on learning and memory of post-stroke depression (PSD) rats and its mechanism.Methods:Four-vessel occlusion method was used to build the rat stroke model and 7 days later these rats were given solitary breeding with chronic unpredictable mild stress (CUMS) to make depression model. Rats were randomly divided into Sham group ( n=10), Model group ( n=10), PSD group ( n=10) and TSPN group ( n=10). The rats in the Model group and PSD group were injected administered with equal volume of 0.9% saline 30 min post-brain ischemia, one injection per day for 30 days. while TSPN group were treated with TSPN. The dose of TSPN (75 mg/kg) was dissolved in 0.9% saline 10 g/L, once per day for 30 days. Then the learning and memory of rats were tested by Morris water maze.The protein levels of DCX and Nestin in the hippocampus were detected by Western blot. Furthermore, the DCX/Ki67 co-labeled cells in the SGZ of hippocampus were observed by the immunofluorescence. Results:The escape latency at the fifth day of PSD group((31.8±3.8)s) was longer than that in the Sham group((10.4±3.2)s) and Model group((19.8±3.7)s) ( t=9.23, 5.15; both P<0.05). The escape latency ((14.2±2.8)s) of TSPN group was shortened significantly than PSD group ( t=8.56, P<0.05). The times across the platform in the Sham group was (10.3±1.7), and the PSD group was (4.1±1.1), difference was statistically significant between two groups( t=11.24, P<0.05). The times across the platform (8.4±1.6) of TSPN group statistically increased compared with PSD group ( t=5.77, P<0.05). The protein levels of DCX and Nestin in the PSD group were (0.60±0.02), (0.58±0.03) respectively, and in the TSPN group were (1.07±0.07), (0.95±0.11) correspondingly, there were significant differences of the DCX, Nestin protein level between the two groups( t=20.22, 7.68, both P<0.01). Moreover, there was significant difference in the number of the DCX/Ki67cells in the hippocampus SGZ between the PSD group((16.2±2.8) /mm 2) and TSPN group ((21.2±3.1) /mm 2)( t=2.42, P<0.05). Conclusion:TSPN could improve the learning and memory of the rats with post-stroke depression through enhancing the hippocampus neurogenesis.

Objective To study the ambient radiation of patients undergoing ¹⁸F-FDG PET/CT myocardial metabolism imaging, and to provide data for protection of surrounding people against radiation. Methods A total of 33 patients were selected for ¹⁸F-FDG PET/CT myocardial metabolism imaging. Dose equivalent rate was measured at the height of patient chest, in different directions, at different time points and at different distances, to investigate the distribution of ambient radiation of the patient. Results At the same time point and distance, the dose equivalent rates at the left and right sides of the patient were lower than the front and back sides. The dose equivalent rate at 1 m in front of the patient was 13-21 μSv/h after ¹⁸F-FDG injection, and decreased to 5-14 μSv/h after PET/CT imaging, with a mean decrease of 46%. The ambient dose equivalent rate decreased exponentially with distance (10~300 cm), and the mean power was −1.2. Conclusion The ambient radiation of patients undergoing ¹⁸F-FDG PET/CT myocardial metabolism imaging was high after ¹⁸F-FDG injection, and the ambient dose equivalent rate decreased rapidly with time and distance. Our results suggest that patients undergoing myocardial metabolism imaging should avoid prolonged and close contact with other people on the day of examination.