小鼠胚胎体外培养条件的研究

在绵羊妊娠后期通过宫内手术经胎羊腹主动脉少量多次注射微球悬液，微球经脐动脉进入胎盘循环，阻塞胎盘的小血管，从而建立胎儿窘迫的动物模型，并通过胎羊动脉血气分析及酸碱度检测和胎羊组织的病理学观察，对该模型进行评价。结果表明胎儿血气和酸碱度的变化符合胎儿窘迫的临床表现，母体因素对模型的建立没有影响。     

阿糖胞苷体外对人白血病细胞株HL-60细胞增殖抑制和诱导凋亡的相关性研究

目的 　研究阿糖胞苷 (Ara -C)在体外对人白血病细胞株HL - 6 0增殖抑制和诱导凋亡的剂量 -时间 -效应关系。通过对Ara -C在不同剂量和疗程时抗白血病的机理研究 ,验证大剂量阿糖胞苷 (HD -AraC)治疗血液肿瘤的优越性。方法 　在体外设定的浓度梯度和作用时间下应用Ara -C处理人白血病HL - 6 0细胞 ,采用四氮唑盐还原法 (MTT法 )检测Ara -C对HL - 6 0细胞增殖抑制的剂量 -时间 -效应关系 ,荧光染色观察凋亡细胞形态学改变 ,琼脂糖凝胶电泳测定DNA梯带 (DNA ,Lad der) ,流式细胞仪检测细胞凋亡率和细胞周期变化。结果　荧光染色观察到特异性的凋亡小体形成 ,DNA琼脂糖凝胶电泳显示出典型的电泳条带变化 ,流式细胞仪检查见明显的凋亡峰形成 ,细胞周期主要阻滞在sub -G1期。MTT法显示阿糖胞苷作用于HL - 6 0细胞的半数抑制浓度 (IC50 )分别是 2 .4 1 μM和 1 1 .81 μM。统计分析表明 :随着药物浓度的增加和作用时间的延长 ,Ara -C对细胞的增殖抑制和诱发凋亡作用逐渐增强 (P <0 .0 5)。结论　诱导白血病细胞凋亡可能是Ara -C抗白血病的机理之一 ,通过诱导HL - 6 0细胞凋亡从而对其产生明显的增殖抑制作用 ,且与剂量、时间相关。提示应用HD -AraC治疗白血病 ,可以明显提高疗效。     

HER2 discordance between paired primary gastric cancer and metastasis:a meta-analysis

Background:A number of stuthes have examined human epidermal growth factor receptor 2(HER2)status in primary gastric cancer(GC) and associated metastasis,some showed their great concordance in HER2 expression,but others demonstrated notable discordance.There is still little consensus on HER2 discordance,therefore,a systematic review and meta-analysis was conducted to assess the status on HER2 discordance between primary GC and its paired metastasis.Methods:PubMed,EMBASE,ASCO and The Cochrane Library were searched for stuthes that explored the concordance between primary tumor and metastasis in patients with GC up to 10 March,2014.Data of discordance of HER2 between primary GC and corresponding metastasis were extracted from the publications and random-effects models were used to estimate pooled discordance proportions.Results:Eighteen articles including 1,867 patients were included for the meta-analysis in accordance with the selection criteria.Pooled discordance proportions were 7%[95%confidence interval(CI):5-10%]for HER2 status.Pooled proportions of tumors shifting from positive to negative and from negative to positive were 17%(95%CI:7-29%) and 4%(95%CI:2-6%) respectively.No publication bias was found in the meta-analysis.Conclusions:The discordance of HER2 status is not rare in primary and metastatic GC through our metaanalysis.Prospective stuthes are needed to testify the clinical significance of the discordance of HER2 status.