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91.
Yan-Wei Hu Chun-Yu Liu Chong-Min Du Jian Zhang Wen-Qian Wu Zhen-Lun Gu 《Journal of ethnopharmacology》2009
Aim of the study
Flavonoids extracted from the seeds of Astragalus complanatus R.Br. reduce the proliferation of many cancer cells. The present study was carried out to evaluate the effects of these flavonoids from Astragalus complanatus (FAC) on human hepatocarcinoma cell viability and apoptosis and to investigate its mechanisms of action in SMMC-7721 cells.Materials and methods
Cell viability was measured using the MTT assay. To detect apoptotic cells, SMMC-7721 cells treated with FAC were stained with Hoechst 33258 and subjected to agarose gel electrophoresis. Quantitative detection of apoptotic cells was performed by flow cytometry. The effects of FAC on apoptosis and cell cycle regulatory genes and proteins in SMMC-7721 cells were examined using an S series apoptosis and cell cycle gene array and Western blot analysis.Results
The growth of SMMC-7721 and HepG2 cells was inhibited by treatment with FAC. Cell death induced by FAC was characterized by nuclear condensation and DNA fragmentation. Moreover, the cell cycle was arrested in the G0/G1 and S phases in FAC-treated SMMC-7721 cells. A sub-G1 peak with reduced DNA content was also formed. The activity of caspase-3 was significantly increased following FAC treatment. Microarray data indicated that the expression levels of 76 genes were changed in SMMC-7721 cells treated with FAC: 35 genes were up-regulated and 41 were down-regulated. Western blot analysis showed that caspase-3, caspase-8, Bax, P21, and P27 protein levels in SMMC-7721 cells were increased after 48 h of FAC treatment, while cyclinB1, cyclinD1, CDK1, and CDK4 protein levels were decreased.Conclusions
These results suggest that FAC may play an important role in tumor growth suppression by inducing apoptosis in human hepatocarcinoma cells via mitochondria-dependent and death receptor-dependent apoptotic pathways. 相似文献92.
Qiong Xu Junqi Ling Gary S P Cheung Yan Hu 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(4):e109-e113
OBJECTIVE: The aim of this study was to evaluate the sealing ability of 4 different obturation techniques by using a glucose leakage test. STUDY DESIGN: Eighty extracted single-rooted maxillary incisors were selected for the study. The teeth were decoronated and the root canals prepared using ProFile rotary instruments to an apical dimension of size 40 (0.06 taper). The specimens were then randomly divided into 4 experimental groups (n = 15) and filled with gutta-percha and sealer by using either cold lateral compaction, warm vertical compaction, Thermafil, or the E & Q Plus system. Another 10 teeth each served as the positive and negative controls. A glucose leakage model was used for quantitative evaluation of the coronal-to-apical microleakage at 24 hours, 1, 2, 3, 5, 8, and 12 weeks. RESULTS: No significant difference in the cumulative amount of leakage was found among the 4 groups at 24 hours and 1 week (Kruskal-Wallis test, P > .05). Lateral compaction showed significantly more leakage than the other 3 techniques at longer intervals (Mann-Whitney U test, P < .008). No significant difference was found between vertical compaction, Thermafil, and E & Q Plus at all observation times. CONCLUSIONS: Warm vertical compaction, Thermafil, and the E & Q Plus system showed a better sealing result than cold lateral compaction of gutta-percha at extended observation periods. The glucose leakage method used in this study was able to provide a nondestructive, quantitative, and long-term evaluation of the sealing ability of root canal fillings. 相似文献
93.
pH值对IFN-α2b、rIL-2、ADM合用维拉帕米对人肝癌细胞杀伤作用的影响 总被引:1,自引:0,他引:1
目的 观察培养液在 pH值为 6 .8、7.3、7.6条件下rIL - 2、IFN -α2b、ADM及合用维拉帕米对人肝癌细胞 74 0 4杀伤作用的影响。方法 MTT法于 96孔培养板上进行杀伤实验 ,测定培养液pH值分别为 6 .8、7.3、7.6状态下 ,rIL - 2、IFN -α2b、ADM、及与维拉帕米联合杀伤人肝癌细胞 70 4 0的差异。结果 pH值为 7.6状态下rIL - 2、IFN -α2b、ADM及合用维拉帕米杀伤效果最佳。pH值为 6 .8、7.3、7.6时 ,IFN -α2b都能增加ADM抗肿瘤作用 ,但pH值为 7.6时 ,IFN -α2b +ADM杀伤效果最佳。结论 在偏硷性环境下 ,rIL - 2、IFN -α2b、ADM及合用维拉帕米对肿瘤细胞杀伤效果最佳 相似文献
94.
目的 探讨贫困地区超声乳化联合小切口硬核白内障摘除联合PMMA人工晶状体植入手术的疗效。方法 对336例(336只眼)Ⅳ级以上核白内障行超声乳化联合小切口晶状体摘除联合PMMA人工晶状体植入术。结果 术后1天、3天视力在0.5以上分别为240只眼(71.4%)、265只眼(78.8%)。术中主要并发症为后囊破裂。术后主要并发症为角膜水肿、眼压升高。结论 超声乳化联合小切口晶状体摘除治疗Ⅳ级以上核白内障切口小,术后反应轻,散光小,并且视力恢复快,费用低。手术技巧的提高可避免或减少术中术后并发症。 相似文献
95.
我们自2000年10月至2008年12月采用大承气汤加黄连应用与肛周常见疾病术后病人,治疗其术后大小便潴留,里急后重等症状,取得了满意的疗效,现报告如下. 相似文献
96.
8年间剖宫产率及指证变化的临床分析 总被引:3,自引:1,他引:2
近年来,我国各地的剖宫产率均呈明显的上升趋势,部分地区的剖宫产率甚至高达60%。居高不下的剖宫产率已引起了广大产科工作者和全社会的广泛关注。对我院近8年来剖宫产病例的临床资料进行回顾性分析,以寻求剖宫产率逐年上升的原因及探讨降低剖宫产率的途径与方法。 相似文献
97.
98.
Described in 1981 by the Chinese authors Yang Kuofan et al. [1] as a free flap, then in 1982 by Lu et al. [2] as a retrograde
flow pedicle flap, this fasciocutaneous flap is designed at the level of the anterior and external faces of the forearm, and
vascularized by the radial artery via a network of septal arteries. Prior to utilization it must be reversed on its distal
pedicle. This flap allows repairing cutaneous substance loss of the whole hand and fingers. The emergence of the Chinese flap
in the 1980’s resulted in a regression of the Mac Gregor groin flap that was widely used at this time [3,4]. Nevertheless,
other forearm flaps, less “expensive” in terms of vascular involvement [5–9] have reduced its indications. The Chinese flap
however keeps two essential indications: the multi-finger important defect that no other forearmflapmay cover; and composite
substance loss of the thumb (despite the fact that the Chinese flap shares these indications with interosseous artery composite
flaps). 相似文献
99.
目的:探讨多部位采血快速血糖仪检测大鱼际毛细血管葡萄糖用于糖尿病患者血糖监测的准确性及优缺点。方法:对我科47例住院糖尿病患者在知情同意后进行血糖检测。行正常餐实验,在空腹时和正常餐后2h分别采静脉血用葡萄糖氧化酶法测定血糖、采手指血用乐康全血糖仪测定血糖、采手掌大鱼际血用Free- style多部位采血血糖仪检测血糖;同时进行采血疼痛感和使用方便性的主观调查,分最好、好、一般和差4级,转换为数字1、2、3、4进行评价。结果:3组的空腹血糖值差异无显著性(P>0.05);餐后2h血糖差异有显著性(P<0.05)。3组的空腹血糖及餐后2h血糖均有良好的线性相关(r=0.759~0.795,P<0.001)。3个部位的测试结果间均呈良好的线性相关,决定系数(R~2)=0.576~0.651(P<0.001)。两种血糖仪的使用方便性无明显差异.指尖采血的疼痛性要强于手掌大鱼际采血(P<0.05)。结论:多部位快速血糖仪(Freestyle)手掌大鱼际采血检测血糖的结果可靠,是糖尿病患者长期监测血糖的一种较为准确、方便、痛苦较少的方法。 相似文献
100.