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101.
参三七皂甙Rg1对实验性血栓形成的影响及其机制探讨   总被引:14,自引:0,他引:14  
用大鼠动静脉血栓形成模型,研究参三七皂甙Rg1抗血栓作用。结果表明,参三七皂甙Rg1可明显降低实验性血栓形成,对大鼠血浆纤溶系统亦有明显作用,可升高血浆中组织纤溶酶原激活物(t-PA)活性和活性型t-PA百分比,降低组织纤溶酶原激活物抑制剂(PAI)活性。同时利用培养大鼠血管内皮细胞实验,发现Rg1可以剂量依赖性提高血管内皮细胞一氧化氮(NO)释放。提示Rg1抗血栓作用与增强纤溶系统活性,促进血管内皮NO释放有关。  相似文献   
102.
用肾性高血压左室肥厚(LVH)大鼠模型,观察了间硝地平(m-Nif)和硝苯地平(Nif)长期给药(ig20mg·kg-1·d-1持续9周)对左室舒张功能、左心室肌和大脑线粒体及血管钙含量的影响。与假手术组相比,LVH组左室顺应性明显下降,僵硬度增高,左心室肌和大脑线粒体及尾动脉和主动脉钙含量增加。与LVH组相比,m-Nif和Nif各组左室顺应性改善,僵硬度降低(P<0.01),左心室肌线粒体及尾动脉和主动脉钙含量较LVH组显著降低(P<0.01)。两药在作用强度上无显著差异。  相似文献   
103.
Innovation in clinical method: diabetes care and negotiating skills   总被引:6,自引:1,他引:5  
The development of a method to facilitate clinical negotiationwith diabetic patients is described. The principles of the methodincorporate patient centredness, an assessment of readinessto change and some elements of motivational interviewing. Asimple low cost technology is part of the innovative method.Details of the method and its application are published beforethe results of a randomized controlled trial to ensure thatthe techniques are in the public domain before the outcome ofthe trial is known.  相似文献   
104.
Leucocytoclastic vasculitis associated with hepatitis C virus antibodies   总被引:1,自引:1,他引:0  
The actiopathogenesis of leucocytoclastic vasculitis is still unknown, but recently hepatitis C virus (HCV) has been suggested as trigger of autoimmunity. We report a case of a 26-yr-old patient with purpura due to leucocytoclastic vasculitis associated with hepatitis C virus infection. Laboratory findings showed AST, ALT, gamma GT within normal limits, positive antibodies to HCV (IIF and Riba II) and polymerase chain reaction for HCV RNA. Anti-nuclear antibodies, IgG and IgM anti- cardiolipin antibodies, anti-platelet antibodies and anti-neutrophil cytoplasmic antibodies with perinuclear pattern were also present. A skin biopsy specimen of a purpuric lesion showed leucocytoclastic vasculitis with small vessel thrombosis and perivascular deposition of IgM and fibrinogen on immunofluorescence study. This case shows a role of HCV in leucocytoclastic vasculitis; it is possible that this HCV can induce autoimmunity independently of cryoglobulins and liver involvement.   相似文献   
105.
Central thrombi in pulmonary arterial hypertension detected by MR imaging   总被引:1,自引:0,他引:1  
Fisher  MR; Higgins  CB 《Radiology》1986,158(1):223-226
Differentiation of thrombi from slow flow in the pulmonary arteries, sometimes observed in the presence of pulmonary arterial hypertension, can be equivocal. Magnetic resonance (MR) imaging was performed in a patient with chronic pulmonary thromboembolism and pulmonary arterial hypertension using an electrocardiographically gated technique that allowed visualization of the pulmonary arteries at the end of diastole and multiple times during systole. These images were compared with those of a patient with primary pulmonary hypertension and those of healthy subjects. Thrombi were discrete structures, seen throughout the cardiac cycle on both the first and second spin-echo images, and decreased in signal intensity on the second image. Slow flow increased in signal intensity and changed in structure during the cardiac cycle and was seen best on the second image. MR may play an important role in excluding large central thrombi as the cause of pulmonary arterial hypertension. It is a noninvasive method for defining pulmonary arterial wall thickness and for direct visualization of chronic pulmonary thrombus.  相似文献   
106.
Kaposi's sarcoma is a vascular tumour of multifocal origin occurring primarily on the extremities. The case of a 45-year-old HIV negative and HHV-8 positive man with an asymptomatic reddish macular lesion on the inner layer of the prepuce is described. Although primary penile Kaposi's sarcoma is a relatively uncommon disorder in HIV negative men, dermatologists and venereologists should consider this possibility when treating non-specific penile lesions. A minimal penile lesion with non-distinctive clinical features may sometimes be the exclusive manifestation of Kaposi's sarcoma, making histologic evaluation necessary to establish the diagnosis.  相似文献   
107.
Blood transfusion is one of the principal routes of transmission of Chagas' disease, a major endemic disease in Latin America. Methods for blood screening are not accurate and may yield false results that lead to high social and economic costs. This study compares two methods of diagnosing Chagas' disease (indirect immunofluorescence and hemagglutination) and several enzyme-linked immunosorbent assays (ELISAs) with regard to specificity and sensitivity, by using human sera with known serologic and parasitologic characteristics, as well as samples with discrepant results on conventional serologic tests. An ELISA using recombinant antigens showed no cross-reactivity with sera that were positive for other diseases. All evaluated ELISAs performed well, and their use may lead to a reduction of more than 50 percent in the number of discordant sera. Further improvements are needed in view of the complexity of the serologic diagnosis of Chagas' disease.  相似文献   
108.
一体化PET/MR检查护理规范是关于PET/MR检查过程中对于护理人员的工作要求,包括检查前准备、注射药物护理、检查时护理、检查后护理、对比剂不良反应处理和个人辐射防护。旨在为核医学科护士在临床PET/MR检查中提供实用且行之有效的处理操作规范。  相似文献   
109.
A mouse model for the delta F508 allele of cystic fibrosis.   总被引:4,自引:2,他引:4       下载免费PDF全文
The most common cause of cystic fibrosis is a mutation that deletes phenylalanine 508 in cystic fibrosis transmembrane conductance regulator (CFTR). The delta F508 protein is misprocessed and degraded rather than traveling to the apical membrane. We used a novel strategy to introduce the delta F508 mutation into the mouse CFTR gene. Affected epithelia from homozygous delta F508 mice lacked CFTR in the apical membrane and were Cl-impermeable. These abnormalities are the same as those observed in patients with delta F508 and suggest that these mice have the same cellular defect. 40% of homozygous delta F508 animals survived into adulthood and displayed several abnormalities found in human disease and in CFTR null mice. These animals should provide an excellent model to investigate pathogenesis and to examine therapies directed at correcting the delta F508 defect.  相似文献   
110.
The bacteriophage P1 Cre/loxP system has become a powerful tool for in vivo manipulation of the genomes of transgenic mice. Although in vitro studies have shown that Cre can catalyze recombination between cryptic "pseudo-loxP" sites in mammalian genomes, to date there have been no reports of loxP-site infidelity in transgenic animals. We produced lines of transgenic mice that use the mouse Protamine 1 (Prm1) gene promoter to express Cre recombinase in postmeiotic spermatids. All male founders and all Cre-bearing male descendents of female founders were sterile; females were unaffected. Sperm counts, sperm motility, and sperm morphology were normal, as was the mating behavior of the transgenic males and the production of two-celled embryos after mating. Mice that expressed similar levels of a derivative transgene that carries an inactive Cre exhibited normal male fertility. Analyses of embryos from matings between sterile Cre-expressing males and wild-type females indicated that Cre-catalyzed chromosome rearrangements in the spermatids that lead to abortive pregnancies with 100% penetrance. Similar Cre-mediated, but loxP-independent, genomic alterations may also occur in somatic tissues that express Cre, but, because of the greater difficulty of assessing deleterious effects of somatic mutations, these may go undetected. This study indicates that, following the use of the Cre/loxP site-specific recombination systems in vivo, it is prudent to eliminate or inactivate the Cre recombinase gene as rapidly as possible.  相似文献   
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