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Objective To prove that juxtacrine and paracrine signaling are essential in the culture of spermatogonial stem cells （SSCs） with Sertoli cell feeder layer in vitro. Methods Mice aged 7 d were chosen ... to harvest testes. A two-step enzyme digestion method was applied in testis suspension. The SSCs and Sertoli cells were separated by adherence distinguishing methods and biologically identified by immunofluorescence and Oil Red 0 staining methods. Flow cytometry was used to analyze purity of SSCs. Three groups were constructed according to different culture conditions. SSC and Sertoli cell co-culture group, SSC conditional culture group and SSC routine culture group. The conditional medium was collected from supernate of culture Sertoli cell in vitro and double-concentrated with DMEM/F12 and fetal bovine serum in a proportion of 4.5 ： 4.5 ： 1. The routine medium was DMEM/F12 containing 10% fetal bovine serum. Adherence rates were measured by Trypan blue staining. Absorbance of SSCs of each group was measured by MTT assay and proliferation curves shown to demonstrate proliferative features of SSCs. Proliferative features and colony formation were observed by inverted microscope. With 24 h difference in adherence rates, proliferations were compared and analyzed.Results The adherence rate of co-culture group was greater than that in the others（P〈0.05）, with insignificant difference in conditional culture group and routine group （P〉0. 05）. SSCs of co-culture group showed stable proliferation immediately following inoculation..4 stable colony formed within 7-10 d and maintained for 30 d. SSCs in conditional culture group and routine group decreased rapidly following transient proliferation. Conclusion The actions of SSCs in Sertoli cell cultures in vitro depended on both juxtacrine and paracrine signaling, Sertoli cell paraerine signaling was unable to promote SSC adherence and proliferation alone. več

GnRH是由下丘脑神经元分泌，且在脊椎动物生殖功能中非常的必要。GnRH还被发现存在于脑以外的组织中，在睾丸间质细胞的炎阎醇激素合成过程中发挥了重要的作用。然而，信号通路对其的调节作用仍然不清楚。本研究我们主要检测MAPK信号通路是否参与GnRH激动剂（GnRHa）诱导的雄激素的合成。我们建立了间质细胞的原代培养的方法。不同浓度GnRHa刺激间质细胞不同时间后3D—HSD和苇酮的量通过RT-PCR，Westernblot和RIA测定。在MAPK抑制剂PD-98059存在或不存在的情况下，我们也通过Westernblot的方法检测GnRHa对ERK1／2，JNK和p38的作用。结果显示GnRHa诱导睾酮的合成并且上调3β-HSDmRNA水平以及蛋A水平，同时也激活了ERK1／2水平，但是对JNK和p38的活化没有作用。虽然GnRHa最佳的浓度是100nmnol L-1，最佳时间是24h，但是GnRHa~激细胞5min后ERK1／2活化作用达到最高水平，60min之内恢复到本地水平。而PD-98059则能完全阻滞ERKl／2活化，3β-HSD的上调以及睾酮合成。我们的数据显示GnRH通过ERK途径来调控大鼠睾丸间质细胞雄性激素的合成。GnRH对ERK1／2的活化诱导了3β—HSD基因和蛋白的表达，最终调节大鼠间质细胞类固醇激素的合成。

Bacterial leaf streak, caused by Xanthomonas oryzae pv. oryzicola, is an important disease of rice （Oryza sativa）. Genetic determinants （tatABC genes） of the twin-arginine translocation （Tat） pathway ... from X. oryzae pv. oryzicola strain RsGD42 were cloned and characterized, meanwhile, a tatC disruption mutant was generated. The tatC mutant lacked detectable flagella and was highly impaired in motility and chemotaxis. Furthermore, it was observed that the tatC mutant exhibited a reduced production of extracellular polysaccharide （EPS） and a significant reduction of virulence on adult rice plants compared to wild type strain. However, the tatC mutation in X. oryzae pv. oryzieola strain RsGD42 did not affect the growth rate and the ability to induce hypersensitive response （HR） in nonhost tobacco （Nicotiana tabacum L. cv. Samsun）. In conclusion, the data indicated that the Tat pathway significantly contributed to the virulence of X. oryzae pv. oryzicola. več

R735.2%R730.56; 目的 探索腹腔镜辅助治疗后肠内外营养联合支持治疗对胃癌术后患者机体恢复的临床疗效及安全性.方法 ... 回顾性分析2018年1月至2019年4月该院收治的拟行手术治疗的胃镜病理活检为胃癌的119例患者临床资料.将患者分为传统开腹及全肠外营养组(A组,40例)、腹腔镜辅助及全肠外营养组(B组,40例)和腹腔镜辅助及肠内外营养联合组(C组,39例).比较三组患者术后第8天的相关生化指标(血清总蛋白、清蛋白及血红蛋白)、肠道功能恢复时间、术后住院时间、术后并发症发生情况等.结果 C组患者术后血清总蛋白、清蛋白、血红蛋白等营养指标的改善均明显优于A、B组,术后胃肠道功能恢复、术后住院时间较A、B组明显缩短,且术后并发症发生率较A组低,差异均有统计学意义(P<0.05).C、B组术后并发症发生率比较,差异无统计学意义(P>0.05)结论 腹腔镜辅助胃癌根治术后肠内外联合营养支持治疗对患者术后机体康复的疗效更明显,且能降低并发症发生率,安全可行. več