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81.
氟伐他汀对自发性高血压大鼠阻力血管 功能的影响 总被引:7,自引:0,他引:7
AIM: To evaluate the effects of fluvastatin, a hydroxymethylglutaryl-CoA (HMG-CoA) reductase inhibitor, on the alterations of structure and function of resistant vessels in spontaneously hypertensive rats (SHR). METHODS: Eight-week-old male SHR were given fluvastatin 20 mg.kg-1.d-1 by gavage. Rats were decapitated at 16 wk. Wall-to-lumen area ratios (W/L) of thoracic aorta and mesenteric arteries (3rd grade branch) were assessed by morphometric assay. The effects of fluvastatin on vascular reactivity to sodium nitroprusside (SNP) and norepinephrine (NE), were studied with rings of thoracic aorta and mesenteric arteries isolated from rats. RESULTS: After 8 wk of treatment, histological examination showed that the wall-to-lumen area ratio was lower in SHRflu than that in SHR (0.44 +/- 0.09 vs 0.79 +/- 0.09, P < 0.05). EC50 of vasodilation response was much lower in SHRflu than that in SHR [(4.9 vs 190) pmol.L-1, P < 0.05], while EC50 of mesenteric artery rings from SHRflu was somewhat lower than that of SHR [(0.02 vs 0.04) nmol.L-1, P > 0.05]. In both aortic and mesenteric artery rings, EC50 of vasoconstriction in response to NE from SHRflu was higher than that of SHR [thoracic aorta: (0.20 vs 0.02) nmol.L-1, P < 0.05; mesentric arteries: (1.46 vs 0.72) nmol.L-1, P < 0.05]. CONCLUSION: Short-term treatment with fluvastatin ameliorated the vasomotoricity of resistant vessels, enhanced the sensitivity to vasodilator and depressed the sensitivity to vasoconstrictor; fluvastatin also attenuated the resistant vascular hypertrophy during the development of hypertension in SHR. 相似文献
82.
Campylobacter jejuni is a major cause of human enteritis which mimics the inflammatory bowel disease (IBD). In this study, microstructural changes on the surfaces of the murine gastrointestinal tract persistently colonized by Campylobacter jejuni, strain GJ-S131, were investigated by using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results revealed that the appearance of the gastrointestinal mucosa in both BALB/C and KM mice resembled that in human with inflammatory bowel disease. Under SEM, the mucosa of the jejunum and ileum, with broken or distorted villi had a "worm eaten" look; crypts were irregular in shape and size, and the mucosa showed atrophy, especially in the colon. Epithelial junctions demonstrated furrows, clefts or deep crevasses, with exudates containing a large number of leukocytes. Cytologic appearances were characterized by microvilli dysplasia and/or atrophy, patchy erosions or necrosis and pelade-like appearance due to absence of microvilli, which were similar to the findings under TEM.
相似文献
83.
Chen ZM Sandercock P Pan HC Counsell C Collins R Liu LS Xie JX Warlow C Peto R 《Stroke; a journal of cerebral circulation》2000,31(6):1240-1249
BACKGROUND AND PURPOSE: Long-term daily aspirin is of benefit in the years after ischemic stroke, and 2 large randomized trials (the Chinese Acute Stroke Trial [CAST] and the International Stroke Trial [IST]), with 20 000 patients in each, have shown that starting daily aspirin promptly in patients with suspected acute ischemic stroke also reduces the immediate risk of further stroke or death in hospital and the overall risk of death or dependency. However, some uncertainty remains about the effects of early aspirin in particular categories of patient with acute stroke. METHODS: To assess the balance of benefits and risks of aspirin in particular categories of patient with acute stroke (eg, the elderly, those without a CT scan, or those with atrial fibrillation), a prospectively planned meta-analysis is presented of the data from 40 000 individual patients from both trials on events that occurred in the hospital during the scheduled treatment period (4 weeks in CAST, 2 weeks in IST), with 10 characteristics used to define 28 subgroups. This represents 99% of the worldwide evidence from randomized trials. RESULTS: There was a highly significant reduction of 7 per 1000 (SD 1) in recurrent ischemic stroke (320 [1.6%] aspirin versus 457 [2. 3%] control, 2P<0.000001) and a less clearly significant reduction of 4 (SD 2) per 1000 in death without further stroke (5.0% versus 5. 4%, 2P=0.05). Against these benefits, there was an increase of 2 (SD 1) per 1000 in hemorrhagic stroke or hemorrhagic transformation of the original infarct (1.0% versus 0.8%, 2P=0.07) and no apparent effect on further stroke of unknown cause (0.9% versus 0.9%). In total, therefore, there was a net decrease of 9 (SD 3) per 1000 in the overall risk of further stroke or death in hospital (8.2% versus 9.1%, 2P=0.001). For the reduction of one third in recurrent ischemic stroke, subgroup-specific analyses found no significant heterogeneity of the proportional benefit of aspirin (chi(2)(18)=20. 9, NS), even though the overall treatment effect (chi(2)(1)=24.8, 2P<0.000001) was sufficiently large for such subgroup analyses to be statistically informative. The absolute risk among control patients was similar in all 28 subgroups, so the absolute reduction of approximately 7 per 1000 in recurrent ischemic stroke does not differ substantially with respect to age, sex, level of consciousness, atrial fibrillation, CT findings, blood pressure, stroke subtype, or concomitant heparin use. There was no good evidence that the apparent decrease of approximately 4 per 1000 in death without further stroke was reversed in any subgroup or that in any subgroup the increase in hemorrhagic stroke was much larger than the overall average of approximately 2 per 1000. Finally, there was no significant heterogeneity between the reductions in the composite outcome of any further stroke or death (chi(2)(18)=16.5, NS). Among the 9000 patients (22%) randomized without a prior CT scan, aspirin appeared to be of net benefit with no unusual excess of hemorrhagic stroke; moreover, even among the 800 (2%) who had inadvertently been randomized after a hemorrhagic stroke, there was no evidence of net hazard (further stroke or death, 63 aspirin versus 67 control). CONCLUSIONS: Early aspirin is of benefit for a wide range of patients, and its prompt use should be routinely considered for all patients with suspected acute ischemic stroke, mainly to reduce the risk of early recurrence. 相似文献
84.
85.
腹腔镜与腹腔镜辅助乙状结肠代阴道术治疗MRKH综合征 总被引:8,自引:0,他引:8
目的 :总结使用全腹腔镜和腹腔镜辅助下乙状结肠阴道成形术各成功治疗1例Mayer Rokitansky Kuster Hauser综合征 (MRKH综合征 )的经验。方法 :全腹腔镜下使用腔镜闭合切割器切断乙状结肠的近端和远端。自肛门插入腔内圆型吻合器 ,将降结肠与直肠吻合。经会阴于尿道膀胱与直肠之间造穴。将带血管蒂的乙状结肠牵入穴道 ,完成阴道成形。腹腔镜辅助下阴道成形中 ,腔镜闭合切割器切断乙状结肠的远端后 ,于左下腹壁做一辅助切口 ,将近端乙状结肠经此切口拉出至腹腔外。切断乙状结肠近端 ,将乙状结肠的远端开口缝合 2层 ,使之成盲端。近侧端开口置入吻合器之钉钻 ,再行荷包缝合送回腹腔 ,用吻合器行肠吻合。其余步骤同全腹腔镜手术步骤。术后根据临床检查或磁共振成像测量新成形阴道的长度和宽度。结果 :全腹腔镜手术新成形的阴道长 18cm ,宽 4cm。腹腔镜辅助手术新形成的阴道长 19cm ,宽 4cm。两例新形成的阴道黏膜湿润 ,呈粉红色。无术中和术后并发症的发生。结论 :经腹腔镜乙状结肠移植段的长度完全能达到开腹手术的要求。与开放手术比较 ,全腹腔镜乙状结肠代阴道手术在腹壁上不留手术瘢痕 ,美容效果理想。而腹腔镜辅助下阴道成形 ,虽腹壁留有小手术疤痕 ,但操作简便 ,手术时间短 ,手术费用低 相似文献
86.
白细胞介素6和肿瘤坏死因子—α在分泌性中耳炎渗出液中表达及… 总被引:9,自引:0,他引:9
Using enzyme-linked immunosorbant assay (ELISA), we measured levels of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) in middle ear effusions (MEE) from patients with secretory otitis media (SOM) undergoing auripuncture to study the role of cytokines in the pathogenesis of the disease. Significant levels of IL-6 (> 62.5 ng/L) were found in 19 (86.36%) of 22 MEEs and those of TNF-alpha (> 37.5 ng/L) in 19 (70.37%) of 27 MEEs. The mean (+/- s) levels of IL-6 and TNF-alpha were 507.68 +/- 813.11 ng/L and 186.86 +/- 166.93 ng/L, respectively. It revealed that the shorter the course, the higher the concentration of IL-6 in MEE: the longer the course, the higher the concentration of TNF-alpha in MEE. These findings suggested that during the early stages of SOM, IL-6 might participate in the defensive reaction of organism, while TNF-alpha might be closely related to the persistence of SOM, resulting in an excessive inflammatory reaction with a potential for pathological changes. It is concluded that the immunological mechanisms probably play a significant role in the pathogenesis of SOM. 相似文献
87.
再次尿道成形术治疗先天性尿道下裂术后严重并发症 总被引:43,自引:3,他引:43
目的:了解先天性尿道下裂行各种尿道成形术失败后,利用膀胱粘膜行尿道成形术的疗效。方法:将严重狭窄和(或)无法修补的尿瘘瘢痕组织彻底切除,取膀胱粘膜片形成尿道,正位开口于龟头,新尿道内置多孔硅胶支架管作引流。结果:28例中,23例治愈,3例有小尿瘘需作尿瘘修补,2例完全失败,再次作粘膜尿道成形术治愈。结论:各种类型先天性尿道下裂尿道成形失败后,可用膀胱粘膜移植尿道成形,效果良好 相似文献
88.
肽图分析是验证rhIL-2的重要手段之一.rhIL-2具有133个氨基酸,在其一级结构的序列中有四个甲硫氨酸切点,可用化学裂解的方法将甲硫氨酸肽键打开,进行肽谱分析,以对其进行验证.为了有效地对甲硫氨酸进行裂解,我们用70%甲酸溶解CNBr~2,保持CNBr的高浓度小体积,使rhIL-2在1.5mlEppedorf管中,室温条件下有效地打开甲硫氨酸肽键.同时比较了CNBr浓度、裂解时间以及在不同浓度的梯度胶中作SDS-PAGE对实验结果的影响,确定了最佳的实验条件,获得了良好的实验结果.本文虽以rhIL-2为例,但对所有带甲硫氨酸的细胞因子均可用本方法进行肽图分析. 相似文献
89.
熔覆层中的颗粒相分布不仅影响材料性能,同时也是研究熔覆过程各种反应机制的主要依据。本文利用图像分析技术,定量分析了Q235钢表面Cu5%Al激光熔覆层的富铁相颗粒分布情况。发现熔覆过程中在熔池中存在熔体对流环,熔池中的对流带动颗粒运动,是决定熔覆层颗粒分布的主要因素。 相似文献
90.
针刺取穴与骨折愈合疗效关系初探 总被引:3,自引:0,他引:3
目的:初步探讨针刺取穴与骨折愈合疗效的关系,为临床研究和应用提供参考,方法选用48只体重2.0~2.5 kg的雄性纯种大耳白家兔,手术造成新鲜桡骨骨折模型,用区组随机法分为局部和邻近取穴组(A组)、远道和辨证取穴组(B组)、局部和邻近取穴加远道和辨证取穴组(C组)、空白对照组(D组)共四组,术后第一天开始对治疗组分别做电针治疗,于术后7 d、14 d、28 d取材做血液生化学、生物力学、放射学、组织学的观测.比较各组间上述指标的差别.结果:血清碱性磷酸酶含量14 d时A组和C组明显高于B组和D组(P<0.01),骨折标本抗弯强度在28 d时A组和C组明显高于B组和D组(P<0.01),X线量化评分14 d和28d时A组和C组明显高于B组和D组(P<0.05),在各个时段各个指标A组与C组、B组与D组比较均无显著差异(P>0.05).结论:局部和邻近取穴能明显促进骨折愈合,而且具有操作简便,易于推广等优点,远道和辨证取穴则效果不明显,与前者合用也没有明显增强前者的疗效. 相似文献