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951.
952.
PENG Cheng-hong ZHAO Zhi-ming LIU Hong HAN Bao-san WANG Yong FANG He-qing WU Yu-lian GAO Chang-you 《园艺学报》2005,21(2):289-292
AIM: To evaluate the blood compatibility of a new bioartificial reactor membranous material (propylene-acidamide grafted polypropylene membrane, PP-g-AAm) in vitro. METHODS: Contacted PP-g-AAm membrane and PP (polypropylene) membrane with platelet-rich plasma in a swing bed, 37 ℃, to simulate the conditions in vivo, and another group of PRP without any membranes was set as control group. ELISA was used to study the expression of β-thromboglobulin, and flow cytometry was used to study CD62P and CD63 expression of the activated blood platelets after contacting the two kinds of membranes with PRP. Scanning electrical microscopy was used to study the configuration and numbers of platelet cells adhered on the membranes. RESULTS: After contacting with PRP 30 min, β-TG expression showed marked difference between the two kinds of material groups and the control group (P<0.01, P<0.05), and the difference between the two kinds of membrane groups was also significant (P<0.05). There were obviously differences on the expression of CD62P and CD63 between the two kinds of membranes after contacting with PRP for 30 min (P<0.05,P<0.01). When enlarged 10 000 times, the disfiguration of the platelet cells adhered on the two kinds of membranes after one hour were found by scanning electrical microscopy, and the numbers of platelets on the PP membrane were more than the PP-g-AAm membrane markedly. CONCLUSION: The PP-g-AAm membrane has better blood compatibility than the PP membrane. 相似文献
953.
AIM: To investigate the effect of heme oxygenase on vascular remodeling in renal hypertension. METHODS: Male Wistar rats were randomly divided into sham-operated, 2K1C (two-kidney one-clip) and hemin-induced groups. Four weeks after the treatments, the thickness of aortic media and HO enzymatic activity of the aorta were determined. Immunohistochemical staining was carried out to detect protein of HO-1 in the aorta. RESULTS: The blood pressure in 2K1C renal hypertension rats started to increase two weeks after the surgery and stabled at a high level at the 4th week. Hemin, an inducer of HO-1, markedly inhibited the increase in blood pressure. Aortic medium thickness of the 2K1C rats at 4th week was 27.5% thicker than that in the sham-operated rats. The thickness of aortic medium of the hemin-induced rats was 16.1% less than that in 2K1C group. At the 4th week after operation, protein level and enzymatic activity of HO-1 in aorta were higher than that in 2K1C group compared to those in the sham-operated group. CONCLUSION: Renal hypertension caused vascular remodeling and the activation of HO-1. HO-1 induction decreased the blood pressure of renal hypertension and reduced vascular remodeling. 相似文献
954.
AIM: To investigate the effect and mechanism of fluvastatin on the migration induced by platelet derived growth factor-BB (PDGF-BB) and endothelin-1 (ET-1) in cultured vascular smooth muscle cells (VSMCs). METHODS: Cultured VSMCs derived from spontaneously hypertensive rats (SHR) were used. Cell migration was determined by modified Boyden chamber assays. Intracellular free calcium ([Ca2+]i) was measured with fluorescent Ca2+ indicator Fura-2/AM. RESULTS: PDGF-BB and ET-1 significantly induced VSMCs migration, which was inhibited by pretreatment of VSMCs with fluvastatin (10-9-10-5 mol/L) in a dose-dependent manner, and the peak inhibition rate of migration induced by PDGF-BB and ET-1 was over 86.67%. Fluvastatin also attenuated the increase in [Ca2+]i induced by PDGF-BB and ET-1, with a peak inhibition rate of 86.76% and 65.32%, respectively. CONCLUSION: PDGF-BB and ET-1 promote migration of VSMCs from SHR.Fluvastatin may have direct inhibitory effects on cell migration induced by PDGF-BB and ET-1. The increase in [Ca2+]i may acts as intracellular signaling in the migration in response to PDGF-BB and ET-1 in VSMCs. 相似文献
955.
ZHANG Hui-ying HAN De-wu WANG Xin-guo ZHAO Yuan-chang ZHOU Xin ZHAO Hai-zhen 《园艺学报》2005,21(11):2238-2242
AIM: The goal of the present study was to evaluate the possibility about enterogenous endotoxemia in pathogenesis of hepatopulmonary syndrome. METHODS: The rat model of cirrhosis was prepared with compound factors. A small dose of lipopolysaccharide (LPS) was administered intraperitoneally once to aggravate endotoxemia of animal with cirrhosis. The normal rats injected with LPS or injected with LPS combined with glycine (LPS antagonist) were designed as controls. RESULTS: Hepatopulmonary syndrome of rats with cirrhosis had occurred in the end of eighth weeks. Pulmonary pathological changes of cirrhosis rats were exacerbated after administration of a given dose of LPS. Glycine sharply antagonized the biological effect of LPS in vivo and in vitro, inhibited the production of TNF-α by LPS and alleviated various pathological changes of hepatopulmonary syndrome. CONCLUSIONS: Enterogenous endotoxemia in cirrhosis rats might be an important mechanism in the development of hepatopulmonary syndrome. Endotoxin and its mediating effect by way of cytokines (TNF-α) may play a role in the pathogenesis of hepatopulmonary syndrome. 相似文献
956.
957.
非无菌操作下分离尖孢镰刀菌的培养基 总被引:7,自引:0,他引:7
尖孢镰刀菌(F.oxysporum)是一类非常重要的土传病原真菌,寄主范围广,可引起100多种植物的萎蔫型病害。 相似文献
958.
体外培育赤眼蜂研究进展 总被引:2,自引:0,他引:2
体外培育赤眼蜂的国内外研究已达到相当平:随着人工饲料配方的优化,选用的人工卵壳材料更适合于赤眼蜂的寄生与发,以及人工卵卡机的研制成功和性能不断改进,产业化体外培育赤眼蜂已成为可能。体外培育赤眼蜂的品质管理问题是实现产业化体外培育赤眼蜂的关键。然而,国内外对体外培育赤眼蜂的品质管理研究涉及甚少,有待进一步研究。本文指出应开展体外培育赤眼蜂生物学特性、行为学特性和分子生物学特性的研究,并应用于品质管理,建立体外培育赤眼蜂的品质管理体系,促进实现体外培育赤眼蜂产业化的进程,从而满足农业生产上对赤眼蜂种群的大量需要。另外,人工卵滞育贮存法的突破有助于实现体外培育赤眼蜂的产业化,也应加强研究,最后,本文对体外培育赤眼蜂的应用前景进行了展望。 相似文献
959.
我国烟草业改革之路 总被引:5,自引:0,他引:5
韩灵梅 《河南科技大学学报(农学版)》2003,23(4):70-72
针对目前我国烟草行业发展中存在的经营管理体制不完善、行业整体技术水平较低、“两烟“市场基本饱和、入世后国际竞争加剧及社会舆论环境对烟草行业的发展压力加大等问题,提出了深化烟草行业体制改革,大力推进企业组织结构调整,建立和完善专卖制度下适应市场经济要求的烟草市场体系等改革发展思路。 相似文献
960.
细胞钙超载与鸡柔嫩艾美耳球虫病损伤关系 总被引:1,自引:0,他引:1
为探讨鸡柔嫩艾美耳球虫(E.tenella)宿主细胞损伤与钙超载的关系,采用组织定量检测、Von Kossa钙染色、焦锑酸钾电镜细胞化学技术对使用和未使用钙离子阻断剂的E.tenella感染鸡盲肠组织的细胞沉积钙、ATP酶、磷脂酶A2(PLA2)、游离脂肪酸和盲肠上皮细胞游离Ca^2+的含量与分布进行了动态测定和分析。结果表明:(1)鸡患柔嫩艾美耳球虫病过程中,宿主细胞内钙和游离Ca^2+明显增多(P〈0.01),并随盲肠损伤加重而增加;(2)在发病过程中盲肠组织Na^+-K^+-ATP酶、Ca^2+-Mg^2+-ATP酶、总ATP酶活性均有不同程度的下降,在感染严重期显著低于不感染对照组(P〈0.01);(3)钙超载盲肠组织的PLA2活性和游离脂肪酸含量明显升高(P〈0.01),表明钙超载是鸡柔嫩艾美耳球虫病的一个重要损伤机制;(4)硝苯地平可以阻止Ca^2+内流,减少宿主细胞内游离Ca^2+,减轻宿主细胞的损伤,在本病发生的早期盲肠损伤较轻时,对鸡有一定的保护力,但随着疾病的发展,其作用下降。 相似文献