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81.
地塞米松体外诱导宫颈癌细胞株凋亡及其机制的研究 总被引:4,自引:0,他引:4
目的 :研究地塞米松 (Dex)体外能否诱导宫颈癌细胞株 (HeLa细胞 )发生凋亡及其机制。方法 :采用透射电镜、DNALadder、流式细胞仪等方法进行凋亡检测 ,用ECLWesternblot方法检测凋亡过程中相关基因表达的变化。结果 :地塞米松体外作用于HeLa细胞后 ,透射电镜观察到了凋亡小体 ;DNALadder法也检测到了凋亡时DNA降解形成的梯带 ;流式细胞仪检测到了细胞凋亡峰 ,且峰值随着处理时间的延长而增高。在凋亡过程中 ,凋亡相关基因bcl 2表达下调 ,而p5 3基因表达无明显改变。结论 :地塞米松体外能诱导HeLa细胞发生凋亡 ,其机制与bcl 2基因的表达下调有关 相似文献
82.
Radio frequency transmyocardial revascularization enhances angiogenesis and causes myocardial denervation in canine model 总被引:4,自引:0,他引:4
Yamamoto N Gu A DeRosa CM Shimizu J Zwas DR Smith CR Burkhoff D 《Lasers in surgery and medicine》2000,27(1):18-28
BACKGROUND AND OBJECTIVE: Transmyocardial revascularization (TMR) relieves angina and improves exercise tolerance in patients. Angiogenesis and myocardial denervation have been proposed as factors contributing to these benefits. To test whether radio frequency transmyocardial revascularization (RF-TMR) enhances angiogenesis and causes myocardial denervation. STUDY DESIGN/MATERIALS AND METHODS: RF-TMR channels were created in 12 dogs which survived up to 4 weeks. Bromodeoxyuridine was administered subcutaneously to mark proliferating cells as an assay of angiogenesis. Western blot analysis of tyrosine hydroxylase and blood pressure response to topical bradykinin were used as indices of myocardial denervation. RESULTS: RF-TMR increased local vascularity by an average of 50%, whereas the rate of vascular cell proliferation was tripled over that of the untreated region. Changes in mean arterial pressure with bradykinin and tyrosine hydroxylase content were significantly decreased in RF-TMR regions as compared with normal myocardium in the same hearts. CONCLUSION: RF-TMR enhances angiogenesis and causes myocardial denervation in canine myocardium as with laser TMR. 相似文献
83.
PRINCIPAL CARDIOVASCULAR COMPLICATIONS IN END STAGE RENAL DISEASE: Cardiovascular diseases are the leading causes of morbidity and mortality in end stage renal disease patients. Very often, complications observed are left ventricular hypertrophy and various forms of arterial degenerative lesions involving coronary arteries, less frequently pericarditis and calcifying valvulopathy are diagnosed. THE REASONS ARE COMPLEX: Risk factors can be either specific of uremia per se such as anemia, overhydration, fistula or the same as in the general population. Hemodynamic alterations including tensile stress or blood flow play a major role associated to various locally or generally generated substances whose role remains currently to be determined. THEIR TREATMENTS: Treatments of cardiovascular complications are not specific in this end stage renal disease population but are more often the treatment of the etiology: reduction of fistula blood flow, increase of hemoglobin, best control of weight gain between two hemodialysis sessions or blood pressure control. 相似文献
84.
85.
F-actin fiber distribution in glomerular cells: structural and functional implications 总被引:7,自引:0,他引:7
Cortes P Méndez M Riser BL Guérin CJ Rodríguez-Barbero A Hassett C Yee J 《Kidney international》2000,58(6):2452-2461
BACKGROUND: Glomerular distention is associated with cellular mechanical strain. In addition, glomerular distention/contraction is assumed to influence the filtration rate through changes in filtration surface area. A contractile cytoskeleton in podocytes and mesangial cells, formed by F-actin-containing stress fibers, maintains structural integrity and modulates glomerular expansion. In this study, the glomerular cell distribution of F-actin and vimentin filaments was studied in normal control and nine-month streptozotocin-diabetic rats. Results in situ were compared with observations in tissue culture. METHODS: Microdissected rat glomeruli were perfused to obtain a physiological 25% glomerular expansion over the basal value. Fixation was done without change in glomerular volume. Dual fluorescent labeling of F-actin and vimentin was carried out, and samples were examined by confocal laser scanning microscopy. RESULTS: The podocyte cell bodies and their cytoplasmic projections, including the foot processes, contained bundles of vimentin-containing fibers. Except for a thin layer at the base of foot processes, they did not demonstrate F-actin. While mesangial cells in culture had F-actin as long stress fibers resembling tense cables, mesangial cells stretched in situ contained a maze of short tortuous F-actin fibers organized in bundles that often encircled vascular spaces. This fibrillar organization was disrupted in diabetic glomeruli. CONCLUSION: Mesangial cells, but not podocytes, contain a cytoskeleton capable of contraction that is disorganized in long-term diabetes. Together with previous observations, the distribution of this cytoskeleton suggests that mesangial cell contraction may be involved in the redistribution of glomerular capillary blood flow, but not substantially in the modulation of glomerular distention. Disorganization of stress fibers may be a cause of hyperfiltration in diabetes. 相似文献
86.
以脉冲角加速度刺激在豚鼠记录出短潜伏期诱发反应,反应由发生于刺激开始后10ms以内的5~7个波组成,高强度刺激时反应振幅数微伏,I波潜伏期约2.5ms,不同动物及同一动物不同时间测试反应非常稳定。系列实验结果表明脉冲角加速度刺激诱发的豚鼠短潜伏期诱发反应系前庭诱发电位。 相似文献
87.
多囊卵巢综合征患者血清生长激素和泌乳素对左旋多巴反应的研究 总被引:1,自引:1,他引:1
目的:探讨多囊卵巢综合征(PCOS)患者生长激素(GH)和泌乳素(PRL)异常分泌的机理。方法:对黄体生成素(LH)/卵泡刺激素(FSH)≥3的15例患者(I型组)、LH/FSH<3的15例患者(Ⅱ型组)以及20例月经周期正常妇女(对照组),行左旋多巴(L-DA,500mg)兴奋下丘脑-垂体轴功能试验,观察3组GH和PRL的浓度变化。结果:在基础状态下,Ⅰ、Ⅱ型组的GH较低(P<0.01)、PRL较高(I型组,P<0.05);L-DA兴奋试验后,Ⅰ、Ⅱ型组GH的升高程度和PRL的下降程度均低于对照组。结论:PCOS的GH和PRL异常分泌可能与其中枢DA活性不足有关。 相似文献
88.
89.
本研究将180名已婚、一孩、年龄33±5岁,需要使用避孕措施的健康妇女随机分成6组,即IUD组、绞股蓝总甙加IUD组、1号OC片组、40mg、60mg、80mg绞股蓝总甙分别与1号OC片复合的3个试验组.用双盲法给药,连续服用6个月观察脂类代谢和血压的变化.结果显示:以IUD组和1号OC片组的数据为参比值.服用不同剂量绞股蓝总甙复合口服避孕药后无升高TG和TC的趋势,有显著升高HDL-C作用和使APOA_1水平上升的趋势;亦存在降低收缩压的趋势,对舒张压无明显影响,但在服药后3个月时HDL-C水平曾发生暂时性下降. 相似文献
90.
去甲氧柔红霉素联合方案治疗难治性急性淋巴细胞白血病的远期疗效 总被引:6,自引:0,他引:6
目的探讨应用去甲氧柔红霉素(ID)为主的联合化疗方案治疗难治性儿童急性淋巴细胞白血病(ALL)的远期疗效及其临床应用价值。方法初治诱导缓解方案用VILP(长春新碱、去甲氧柔红霉素、左旋门冬酰胺酶、泼尼松)。完全缓解(CR)后作巩固治疗及庇护所治疗,然后再用VILP作早期强化治疗。复发者诱导治疗用IA(去甲氧柔红霉素、阿糖胞苷)方案。CR后巩固和早期强化治疗用初治者同样方案。结果10例初治患儿9例获CR,7例复治患儿5例获CR,总CR率为82%(14/17)。CR的14例中持续CR(CCR)>3年者4例,>2年者4例,>1年者1例。结论用去甲氧柔红霉素为主的联合方案是治疗难治性儿童ALL有效的方法,对初治患儿作为一线药物其远期疗效会更好。 相似文献