巫山淫羊藿悬浮培养细胞的生长特性研究

目的考察巫山淫羊藿悬浮培养细胞的生长特性,为巫山淫羊藿资源利用提供参考。方法选用悬浮培养所获得的均匀悬浮培养细胞为研究对象,在光照条件下进行悬浮培养,每隔3 d取样,测定相关的生理生化指标。结果巫山淫羊藿悬浮细胞的生长曲线呈"S"型,培养基中蔗糖、磷酸盐、硝酸盐、铵盐量均呈急剧下降趋势,最后变化趋于平缓,细胞合成黄酮最佳光照时间为每天12 h,黄酮合成量为27.854 82 mg/L。结论巫山淫羊藿细胞生长特性的研究为其大规模悬浮培养生产天然活性成分奠定了基础。     

研究生教育异化现象的分析与思考

培养高质量的创新型人才是我国的战略发展重点,研究生教育对此负有重任。随着招生规模的扩大,研究生教育出现了异化现象。针对研究生教育培养目标、课程建设、教学方式和师生关系方面的异化,提出了促进研究生教育健康和谐发展的应对策略。     

Sertoli cell-induced effects on functional and structural characteristics of isolated neonatal porcine islets

A lack of a sufficient number of human donor pancreases has stimulated interest in isolation and cryopreservation techniques for islets from the porcine pancreas. But because of a poorly developed outer membrane porcine islets are particularly susceptible to damage during cryopreservation. The aims of this study were two-fold: 1) to develop a method for isolation and storage of islets from neonatal porcine pancreas and, 2) to examine effects of Sertoli cells on islet yield and function in Sertoli cell-islet cell cocultures. A total of 170 neonatal porcine pancreases were processed by means of a short period of digestion with collagenase and culture of the tissues at 32°C for periods up to 7 days following isolation. Results were: The mean ± SEM, number of viable islets, and percentage loss of cells following 7 days of culture were 29, 442 ± 1,119 and 22.2 ± 1.2, respectively. Cryopreservation had a marked impact on recovery of viable islets: In absence of Sertoli cells an average of only 64% of islets remained viable; by contrast, when cryopreserved islets were cocultured with Sertoli cells, a mean of 82% was recovered. Glucose at 16.7 mmol/L had the capacity to elicit insulin release from 3-day-old cultured islets. The concentration in absence of Sertoli cells was 57.3 ± 3.8, uU/mL/10 islets; in the presence of Sertoli cells the level increased to a mean ± SEM of 112.8 ± 17.7, uU/mL/10 islets. Similar results were obtained following cryopreservation: glucose at 16.7 mmol/L stimulated a mean ± SEM of 27.9 ± 6.6, uU/mL/10 islets, of insulin in absence of, and 44.9 ± 9.9, uU/mL/10 islets, in presence of, Sertoli cells. Our results show that isolation and cryopreservation of neonatal porcine islets can be successfully accomplished. In addition, coculture with Sertoli cells significantly improves both the yield and functional capacity of islets following cryopreservation.     

An Efficient Dopant for Introducing Magnetism into Topological Insulator Bi2Se3

In this work, we obtained an effective way to introduce magnetism into topological insulators, and successfully fabricated single crystal C-Bi₂Se₃. The structural, electrical and magnetic properties of non-magnetic element X (B, C and N) doped at Bi, Se1, Se2 and VDW gap sites of Bi₂Se₃ were studied by the first principles. It is shown that the impurity bands formed inside the bulk inverted energy gap near the Fermi level with C doping Bi₂Se₃. Due to spin-polarized ferromagnetic coupling, the time inversion symmetry of Bi₂Se₃ is destroyed. Remarkably, C is the most effective dopant because of the magnetic moment produced by doping at all positions. The experiment confirmed that the remnant ferromagnetism Mr is related to the C concentration. Theoretical calculations and experiments confirmed that carbon-doped Bi₂Se₃ is ferromagnetic, which provides a plan for manipulating topological properties and exploring spintronic applications.     

半夏种内各变异类型主要形态学性状比较研究

目的为半夏各变异类型提供形态学的鉴别和分类依据。方法系统观察并测量各变异类型主要形态学性状,采用多角形图比较其相似性和差异性程度。结果生殖器官中,各变异类型间各性状的差异性较小,但有一个变异趋势,即阔叶类型的雌雄花序长和宽,雌雄间隔,管部长和宽与其它类型相比,数值略小。营养器官中,以叶片长宽比值即叶形的变化最为明显,其它性状在各变异类型间相似。结论叶片长宽比值在各变异类型间差异显著,可作为各变异类型鉴别和分类的依据。     

高校经济困难学生自我和谐调查

目的探讨并揭示高校家庭经济困难学生自我和谐现状。方法运用自我和谐量表（SCCS）对川、浙两地3所高校256名在校家庭经济困难大学生进行团体测验。结果高校家庭经济困难学生的自我和谐程度较低,总体上呈偏态分布;不存在性别差异;自我评价深刻地影响着自我和谐程度。结论高校家庭经济困难学生的自我和谐程度堪忧,需要高校和社会各界给予更多的关注;帮助高校经济困难学生要“物质”、“精神”两手抓。