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31.
AIM:To study the effect of cilazapril on pulmonary vascular endothelial dysfunction in hypoxic rats. METHODS:The structure and function of endothelium in hypoxic rats were studied by biochemical analysis, radioimmunoassay, transmission electron microscope and correlated with hemodynamic. RESULTS:1) The change and damage of ultrastructure in endothelial cell (EC) were obsevered in hypoxic rats. 2) The contents of plasma nitric oxide (NO) and superoxide dismutase (SOD) activity in blood as well as endothelial nitric oxide synthase (eNOS) activity in the lung tissue were significantly lower in the hypoxic rat than those in contral animals. The concentrations of plasma endothelin-1(ET-1) and angiotensin converting enzyme(ACE) as well as malondialdehyde(MDA) were significantly higher in the hypoxic rat than these in contral animals. The relaxing and contracting factors had a significant positive/negative correlation with mean pulmonary artery pressure (mPAP). 3) Cilazapril significantly decreased the level of ET-1 and ACE and significantly increased the level of NO and activity of eNOS and SOD. At the same time, cilazapril extenuated hypoxia-induced injuries of EC. CONCLUSION:The results indicate that damaging structure and dysfunction of EC existes in hypoxic rats. The cilazapril effectively preventes and treates the chronic hypoxic PH by relieving the injury and improving secretion in EC.  相似文献   
32.
组氨醇脱氢酶(HDH)是组氨酸生物合成过程中最后两步反应的催化酶。对组氨醇脱氢酶的结构、催化机理、组氨醇脱氢酶抑制剂等方面的研究动态进行了较为详细的综述。  相似文献   
33.
AIM: To prepare gfp-bcl-XL-contained recombinant adenovirus(rAd-gfp-bcl-XL).METHODS: Bcl-XL gene was amplified from pEGFP-C3-bcl-XL, subcloned into shuttle plasmid and formed transfer plasmid of pAdTrack-CMV-bcl-XL. Then pAdTrack-CMV-bcl-XL was linealinzed with PmeI and co-transformed into BJ5183 bacteria with adenovirus genomic plasmid of pAdEasy-1. The identified recombinant adenovirus plasmid was digested with PacI and transfected into 293 cells to package recombinant adenovirus particles. The target gene was detected by PCR.RESULTS: There were about 35% positive recombinant bacterial clones after the co-transformation of pAdTrack-CMV-bcl-XL and pAdEasy-1 into BJ5183. Recombinant adenovirus particle were produced and further amplified after the transfection of pAdEasy-1-gfp-bcl-XL into 293 cells. PCR test indicated that the recombinant Ad contained bcl-XL gene. The titer of the purified rAd-gfp-bcl-XL was 6.5×1012 PFU/L. CONCLUSIONS: The homologous recombination in bacteria is a convenient and high efficient method to prepare rAd-gfp-bcl-XL. This affords a good gene transfer vector for the gene therapy in human’s diseases.  相似文献   
34.
AIM: To investigate the effects of PD98059 on the differentiation from mesenchymal stem cells to osteoblasts.METHODS: hMSC were separated from human marrow and expanded in cuture medium. hMSC were induced with dexamethasone, β-glycerophosphate, vitamin C which acted as osteoblast differentiation inducer. PD98059 was added into the osteoblasts induction medium. The cells were assayed with cell morphology, alkaline phosphatase (AP) activity and calcium deposition. RESULTS: The isolated cultured MSC comprised a single phenotypic population and displayed a fibroblast-like morphology. After induced with osteoblasts induction medium, the cells showed changes in cell morphology from spindle-shape to cuboidal and polygonal. The AP activity increased gradually and reached the peak in 12 days, then decreased. Many scattered tangerice calcium nodes were observed. PD 98059 significantly inhibited AP activity and calcium deposition in a dose-dependent manner. A striking observation of the present study was that a few adipocytes appeared in cultures that were treated with PD 98059 and osteogenic differentiation medium. CONCLUSION: These results indicated that osteogenic diferentiation from the hMSCs was related to the activation of the ERK.  相似文献   
35.
AIM: To investigate the relationship between somatostatin and the pathologic type, estrogen receptor,DNA ploidy of nuclei in tumor cells of breast cancer.METHODS: 67 cases of primary breast cancer and 25 cases of benign breast tumor were examined by immunohistochemical stretomyces avidin peroxidase method. 26 cases of breast cancer selected at random were analyzed by flow cytometry.RESULTS: Somatostatin expressed significantly higher in low malignant breast cancer than that in high malignant breast cancer (P<0.05). Most of cancers with positive staining of somatostatin were diploidy,most of cancers with negative staining were aneuploidy,there had significant difference between two groups (P<0.05).CONCLUSION: Somatostatin may delay the progress of breast cancer,and somatostatin levels in cancer tissues may become a useful indicator for assessing prognosis of patients with breast cancer.  相似文献   
36.
喀喇昆仑山盖孜河水文水资源特性分析   总被引:2,自引:1,他引:2  
喀喇昆仑山河流自有水文资料记载以来 ,近 10年洪灾发生频率明显高于以往 ,人民的生命财产损失程度也大幅度增加。在分析了盖孜河流域的径流及气候多年变化过程后 ,认为洪灾频发的原因是近年来流域内降水及气温呈上升趋势 ,导致高山冰川退缩 ,河流径流增加 ,洪灾增大、频率增高 ;小区域多年气候变化过程从侧面印证了我国西北地区气候由暖干向暖湿变化。  相似文献   
37.
李强  李学伟 《四川畜牧兽医》2004,31(2):28-28,30
引进丹麦先进仪器FAT—O—MEAT’ER(肉脂仪)对中国鲁梅克斯食品总公司名山县屠宰场中5821头猪进行了现场测定,测量性状为最后一根肋骨处离背中线4~5cm处的膘厚(P2)和倒数第三、四根肋骨之间,离背中线4—5cm处的膘厚(RF)以及眼肌厚度(RM),并估测出瘦肉率。对所测胴体各性状的均数和相关性分析,表明本地商品肉猪胴体质量低于国外水平。  相似文献   
38.
猕猴桃果实成熟前补钙对果实含钙量的影响   总被引:3,自引:0,他引:3  
猕猴桃果实成熟前用喷叶法和喷果法补钙,可显著提高果实中的钙含量。喷叶较喷果效果好。用Ca(NO3)2喷叶,比用CaCl2处理效果好,差异显著。而果实对CaCl2和Ca(NO3)2的吸收选择性差异不显著。经补钙处理的果实采后进行贮藏效果观察发现:用Ca(NO3)2喷叶处理的果实贮藏性较好,用其喷果处理次之;用CaCl2喷果和喷叶处理的果实贮至28天软果率均达到90%。  相似文献   
39.
利用远缘杂交创造核果类果树新种质的研究   总被引:5,自引:0,他引:5  
以桃、杏、李、樱桃、杏梅等果树的 1 4个品种为亲本 ,3年来共进行了 80余个组合的远缘杂交试验 ,探讨了核果类果树远缘杂交的亲和性 ,并对远缘杂种幼胚进行了胚抢救。结果表明 ,铃铛花期授粉的坐果率显著高于初花期授粉 ;同一杂交组合 ,正反交坐果率差异显著 ,母本对远缘杂交亲和性影响很大 ,选择自交亲和或自然坐果率高的种或品种做母本容易克服远缘杂交的不亲和性 ;适宜场强的静电场、He -Ne激光处理及60 Coγ射线与He -Ne激光联合处理花粉 ,均能显著提高花粉离体萌芽率 ,用上述处理的花粉进行的远缘杂交坐果率也明显高于对照 ;60 Coγ射线单独处理则降低了花粉离体萌芽率 ,远缘杂交的坐果率也低于对照 ;对远缘杂种幼胚及时地进行胚抢救 ,并诱导形成多丛芽 ,是克服核果类果树远缘杂种不育性的有效方法。研究并筛选出了李、樱桃胚萌发与生长、多丛芽诱导与增殖以及生根培养等最佳培养基配方。目前已将欧洲甜樱桃×中国樱桃、大石早生李×泰安巴旦水杏及凯特杏×总统李等一批核果类果树远缘杂种定植于露地 ,其中欧洲甜樱桃与中国樱桃的种间杂种是国内外首次获得  相似文献   
40.
AIM: To explore interaction and biological behaviour changes of two kinds of cells-blastocysts and hepatocarcinoma cells in the same microenvironment. METHODS:The models of mouse blastocysts co-cultured with human hepatocarcinoma cell lines were established, then biological behaviours and mutual effects of the two kinds of cells in co-culture system were observed. RESULTS: Compared with control group, hepatocarcinoma cells with differently invasive and metastatic potential significantly enhanced the rates of blastocyst hatchment , attachment and outgrowth(P<0.05). There was no significant difference in those among hepatocarcinoma cells co-cultured groups (P>0.05). The blastocyst hatched and attached to hepatocarcinoma cells with differently invasive and metastatic potential. Then, differential trophoblasts invaded hepatocarcinoma cells. The clear-cut interfaces were gradually formed between both sides. Hepatocarcinoma cells on interface showed changes of growth direction and cell shapes and did not invade blastocysts. CONCLUSIONS: Hepatocarcinoma cells promoted blastocyst development. Blastocysts implanted and invaded hepatocarcinoma cells with differently invasive and metastatic potential in vitro, which indicate that blastocyst implantation in vitro does not relate with the kinds and differential level of interactional cells and the low selectivity maybe relate with high adaptability of early life.  相似文献   
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