Amicon~ Ultra-0.5超滤离心管在脱落细胞DNA提取中的应用

在法医物证检验中,提取产物的DNA浓度是决定该检材能否被检出和发挥作用的关键因素。当浓度较低达不到检测阈值时,常需要对提取产物进行浓缩,常用的浓缩设备为Microcon-100超滤管,但该设备仅被用于联合有机法及Chelex法来浓缩提取产物。

基于原子力显微镜对华蟾素和姜黄素联合诱导Hela细胞凋亡的初步研究

目的:探讨华蟾素和姜黄素联合对人宫颈癌Hela细胞凋亡的影响。方法:采用MTT法检测细胞增殖抑制率,流式细胞术测定细胞凋亡率,原子力显微镜(AFM)探测细胞形貌、细胞表面超微结构及粗糙度变化。结果:MTT实验显示,华蟾素和姜黄素联合对Hela细胞的增殖抑制率(64.04%±1.29%～75.07%±2.19%)较华蟾素单独用药(11.30%±0.6%～22.04%±0.96%)明显增加。流式细胞术结果表明,华蟾素和姜黄素联合诱导Hela细胞早期凋亡率(11.97%±1.36%～49.2%±2.36%)显著大于华蟾素单独用药(8.05%±0.21%～16.43%±0.29%),并且呈剂量依赖性。原子力显微镜(AFM)成像表明,随着联合用药浓度增大,细胞逐渐坍塌,核染色质浓缩和边集,最后核膜破裂,核基质结构虽然存在但遭破坏,呈现凋亡现象;膜表面颗粒粒径增大,平均粗糙度增加。结论:华蟾素和姜黄素联合能够增强诱导Hela细胞凋亡作用,两者联用为协同效应,这为宫颈癌治疗的药物选择提供了新的思路。

Seasonal Variations of Number Size Distributions and Mass Concentrations of Atmospheric Particles in Beijing

Particle number and mass concentrations were measured in Beijing during the winter and summer periods in 2003, together with some other parameters including black carbon (BC) and meteorological conditions. Particle mass concentrations exhibited low seasonality, and the ratio of PM2.5/PM10 in winter was higher than that in summer. Particle number size distribution (PSD) was characterized by four modes and exhibited low seasonality. BC was well correlated with the number and mass concentrations of accumulation and coarse particles, indicating these size particles are related to anthropogenic activities. Particle mass and number concentrations (except ultra-fine and nucleation particles) followed well the trends of BC concentration for the majority of the day, indicating that most particles were associated with primary emissions. The diurnal number distributions of accumulation and coarse mode particles were characterized by two peaks.

内镜下切除胃底固有肌层肿瘤的临床价值研究

目的：探讨胃底固有肌层肿瘤内镜下切除治疗的疗效及安全性。方法回顾性分析2012年1月至2014年6月对内镜超声发现的源于胃底固有肌层的黏膜下肿瘤行内镜下切除的53例患者资料，评价内镜下切除治疗的手术过程及术后风险。结果53例患者均顺利完成内镜下切除治疗，病变直径为0.5～4.5 cm，均一次性完整切除病变，手术时间25～155 min，平均（46.7±18.2）min。术中创面均有不同程度出血，出血量为 5～150 ml，经氩离子凝固术、热活检钳凝固术或金属夹闭合创面止血成功。有8例术中并发穿孔（8／53），7例应用钛夹夹闭或尼龙圈联合钛夹缝合穿孔成功，另1例穿孔直径过大，转腹腔镜腔外缝合，术后给予胃肠减压、质子泵抑制剂抑酸、抗炎等治疗，均无术后出血。内镜下切除术后住院3～14 d，平均（5.3±1.4）d，穿孔患者术后1个月胃镜复查见穿孔均闭合。术后病理诊断46例为间质瘤，7例为平滑肌瘤。所有患者接受随访3～27个月，未见病变残留和复发。结论内镜下切除术不仅符合了胃底局部完整切除固有肌层肿瘤的治疗原则，而且还可获得完整病理结果，是一种安全、有效、值得推广的方法。