MTT法检测极低频弱磁场对SY细胞的影响

本文采用 MTT 示踪法,检测极低频弱磁场对 SY 细胞有无影响。结果发现:频率固定为50Hz 时变化磁场幅值,在150uT、300uT 下细胞吸光度值有明显降低;幅值固定为150uT 时变化磁场频率,在25Hz、50Hz、75Hz 磁场照射下吸光度值均有不同程度下降,而在10Hz、60Hz、100Hz、300Hz、500Hz 磁场照射下没有变化;幅值固定为300uT 时变化磁场频率,在500Hz、75Hz、100Hz、300Hz、磁场照射下吸光度值均有不同程度下降,而在10Hz、25Hz、60Hz、500Hz 磁场照射下没有变化。     

TNF-α在重症胰腺炎大鼠肺组织内的表达及与肺损伤关系的实验研究

目的：观察SAP大鼠TNF-α在肺组织尤其是肺毛细血管内皮细胞的表达，探讨其与肺损伤的关系。方法：SD大鼠55只，随机分为SAP组（再分为0．5、3、6、12、24h5个亚组，各组n=8）和对照组（n=15）。采用逆行胰胆管注射5％牛磺胆酸钠复制重症胰腺炎模型，取肺组织行病理观察，免疫组化SP法观察TNF-α的表达情况。结果：对照组仅有极少量的单核巨噬细胞为阳性表达；SAP各组阳言细胞数明显增多（P〈0．05），强度随病程进展增强，并于12h达高峰，阳性信号主要位于中性粒细胞、单核巨噬细胞胞浆内。TNF-α在对照组微血管内皮细胞中无阳性表达，而在SAP各组有阳性表达，且强度随病程进展增强。结论：TNF-α在SAP肺组织表达增强且与肺损伤密切相关。     

骨骼肌肌细胞增殖及分化过程中凋亡现象

目的 对骨骼肌分化中的凋亡现象进行初步研究,方法 本实验采用体外培养的C2C12肌母细胞分化模型,用流式细胞仪检测肌细胞分化过程中细胞周期的变化,提取细胞基因组DNA进行电泳分析,用原位末端标记法进行了凋亡细胞染色,电子显微镜观察凋亡小体的形成。结果 Ｃ２Ｃ１２细胞在肌分化诱导２４h和４８h,检测出凋亡现象;而对照组、肌分化诱导７２h组均未检出凋亡现象。结论 在肌肉分化、发育的过程中,某些细胞会按自身程序主动死亡,以凋亡细胞的形式排除。而且具有明显的时间性,终末分化的肌管不易出现凋亡。     

肝细胞癌上皮细胞白蛋白和CK7的表达

目的 探讨人类肝癌肝组织是否存在小上皮细胞（small epithelial cell,SEC),这类细胞是否表达白蛋白CK7抗体,对30例人肝细胞肝癌的手术标本材料作免疫组化染色,对其中10例作超微结构观察和白蛋白及CK7的免疫电镜标记。结果 30例中有20例在肝癌肿瘤边缘和增生的小胆管发现有少量SEC。这类细胞既表达白蛋白,又表达CK7。电镜下,这类SEC体积较小,核大,胞质少胞质内主要为游离核糖体,并有胞质内张力微丝及细胞间连接结构。免疫电镜下,10例中有5例可显示在同一SEC同时表达白蛋白和CK7。结论 人肝细胞癌肝中确实存在SEC。这类SEC具有与人肝母细胞瘤和胆道闭锁肝组织中的SEC一样的形态和免疫表型特点。     

行为干预及生物反馈治疗对老年高血压患者降压疗效的影响

目的 研究应用行为干预治疗及生物反馈治疗对老年高血压患者降压药物的影响。方法 在应用降压药物的基础上,增加行为干预及生物馈治疗,观察综合性行为干预措施对降压疗效的影响。结果 增加行为干预及生物反馈治疗后,降压和情绪障碍矫正的效果比单用药物明显改善。结论 老年高血压患者给予综合性行为干预措施可增加降压药物的疗效。     

Characterization and phylogenetic analysis of a neurovirulent Zika virus isolated from Cambodia in 2019

The geographic range of Zika virus (ZIKV) has expanded from Asia to the Americas, leading to the 2015–2016 pandemic with enhanced neurovirulence. At present, ZIKV is continuously circulating in many Southeast Asian countries. Unfortunately, the persistent evolution of ZIKV in Southeast Asia and its influence on the biological characteristics of the virus remain incompletely understood. In this study, the in vitro and in vivo properties of a new ZIKV isolate obtained from Cambodia in 2019 (CAM/2019) were characterized and compared with those of the Cambodian strain (CAM/2010). Compared with CAM/2010, the CAM/2019 virus showed similar plaque morphology and growth curves in cell cultures and induced comparable viremia and organ viral loads profiles in both BALB/c and A129 (IFNAR1^−/−) mice upon intraperitoneal (i.p.) inoculation. Remarkably, the CAM/2019 virus exhibited enhanced neurovirulence in neonatal mice compared with CAM/2010, with a 74-fold reduction in the 50% lethal dose (LD₅₀). Consistently, CAM/2019 produced higher viral loads in the brains of BALB/c neonatal mice than CAM/2010 did. Sequence alignment showed that the CAM/2019 virus has acquired 12 amino acid substitutions, several of which were found to be associated with neurovirulence. In particular, the CAM/2019 virus shared an A1204T substitution in NS2A with the Thai isolate SI-BKK02 that was isolated from a microcephaly case. Taken together, our results indicate that a ZIKV strain isolated with specific mutations has emerged in Cambodia, highlighting the need for extensive molecular and disease surveillance in Cambodia and other Asian countries.     

长引流管在乳癌根治术中的应用

目的：探讨乳癌根治术后放置长引流管对促进术后伤口愈合、预防和减少继发感染的效果;方法：共观察７２例乳癌根治术病例,每例病人在术后均放置前端多侧孔长度９０ｃｍ乳胶引流管,以负压吸引对创曲渗液进行引流;结果：本组病例中没有发生一起与放置长引流管有关的皮瓣感染,仅有２例出现术后切口轻度感染;结论：长引流管的应用能有效促进创面愈合、减少感染。     

Dexniguldipine hydrochloride inhibits growth of human pancreatic adenocarcinoma cells and expression of protein kinase C isoforms alpha and zeta

New therapeutic regimens are needed for the treatment of pancreatic cancer. In view of the importance of protein kinase C (PKC) in tumorigenesis, we evaluated the effects of dexniguldipine hydrochloride (DNIG) on the in vitro growth of CFPAC-1 human pancreatic adenocarcinoma cells and the expression of PKC isoforms. DNIG is a potent antineoplastic drug with well-established anti-PKC activity and the ability to reverse multidrug resistance. DNIG (1.6-25 mu M) decreased the number of cells in culture in a time- and dose-dependent manner with an EC(50) of 4.9 mu M on day 1 and 2.8 mu M on day 3. When PKC isoform expression in CFPAC-1 cells was analyzed by immunoblotting, the predominant isoforms were identified as alpha and zeta. The expression of PKC alpha and zeta was inhibited significantly by DNIG (0.63-2.5 mu M). These results suggest that DNIG suppresses the proliferation of CFPAC-1 pancreatic cancer cells, possibly by inhibiting the expression of specific PKC isoforms.