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OBJECTIVE: To evaluate and compare the effects of lisinopril versus atenolol administration on the diurnal blood pressure profile and the nocturnal blood pressure fall in young mild-to-moderate essential hypertensives.METHODS: Thirty patients were studied. After a 2-week placebo run-in period, they were single-blind randomly assigned to receive 20 mg lisinopril or 100 mg atenolol. Using a SpaceLabs 90207 device, their ambulatory blood pressure was measured before and after 12 weeks of therapy. The readings were analysed using Fourer series with four harmonics. RESULTS: Lisinopril and atenolol administration significantly decreased office and ambulatory blood pressure values compared with the placebo period. The daily blood pressure curves obtained from Fourier analysis showed that the circadian rhythm was not altered by lisinopril and atenolol administration. From the night:day ratio for the nocturnal blood pressure fall, we found that atenolol administration minimized the average night-time blood pressure dip by increasing the number of non-dippers. In contrast, lisinopril administration did not modify the day-night difference, preserving the nocturnal blood pressure fall. CONCLUSION: Lisinopril and atenolol administration as a first-step treatment of young essential hypertensives produced comparable degrees of diurnal control of arterial pressure. The blood pressure fall at night in patients treated with atenolol was slightly less than that found with lisinopril treatment.  相似文献   
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The detection and quantitation of apoptotic cells is becoming increasingly important in the investigation of the role of apoptosis in cellular proliferation and differentiation. The pathogenesis of hematologic disorders such as aplastic anemia and the development of neoplasia are believed to involve dysregulation of apoptosis. To quantitate accurately the proportion of apoptosis cells within different cell types of a heterogeneous cell population such as blood or bone marrow, a method is required that combines the analysis of large numbers of cells with concurrent immunophenotyping of cell surface antigens. In this study, we have evaluated such a method using the fluorescent DNA binding agent, 7-amino actinomycin D (7AAD), to stain three diverse human cell lines, induced to undergo apoptosis by three different stimuli. Flow cytometric analysis defines three populations on the basis of 7AAD fluorescence and forward light scatter. We have shown by cell sorting and subsequent morphological assessment and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling that the populations defined by 7AAD represent live, apoptotic, and late-apoptotic/dead cells. This method is quick, simple, reproducible, and cheap and will be a valuable tool in the investigation of the role of apoptosis in normal physiology and in disease states.  相似文献   
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The authors report the case of a woman with a primary hemangiopericytoma of the lung and successive metachronous diaphragmatic metastasis treated with surgery only according to the patient's decision. The patient was first submitted to left lower lobectomy with resection of diaphragm and three ribs en-bloc for pulmonary sarcoma. One year later, a chest computed tomography (CT) scan showed a small lesion above the diaphragm on the left side. She refused the proposed operation and returned fifteen months later with a new thorax CT, and told us that she had in the meantime become pregnant and given birth. A rethoracotomy to remove the metastatic diaphragmatic tumor was performed. Chemotherapy with anthracycline and iphosphamide was proposed, but the patient again refused therapy for fear of side effects impairing another pregnancy. Currently, the patient is alive and disease-free, 68 months after the first treatment. The authors emphasize the long-term follow-up obtained with surgery alone in this kind of rare sarcoma.  相似文献   
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力竭运动大鼠心室肌蛋白质组表达特征   总被引:3,自引:0,他引:3  
目的:采用蛋白质组学技术,建立安静和递增运动负荷训练后力竭大鼠心室肌蛋白质组的差异性表达谱,初步筛选出心室肌对力竭运动产生反应的目标蛋白质。方法:实验于2007-03在湖南师范大学生命科学学院蛋白质化学与蛋白质组学国家教育部重点实验室和省级运动人体科学实验室完成。①实验分组:10只SD雄性大鼠随机分为对照组和运动组,每组5只。②实验方法:运动组经过7周的大强度递增运动负荷训练后(最后一次力竭),对两组心室肌组织的全蛋白进行双向凝胶电泳分离。结果:经图像分析,在运动组的电泳图谱上共展现蛋白质点(338±17)个,对照组展现蛋白质点(352±17)个。运动后差异表达的蛋白质点共有99个。对其中差异表达的9个蛋白质点进行质谱鉴定,共鉴定出7个蛋白质,Stress-70protein,NADH-ubiquinone oxidoreductase Mr75000subnunit,Long-chain specific acyl-CoA dehydrogenase,Tropomyosin-1alphachain在运动后"缺失",Nitrilase family,member2在运动后表达上调在5倍以上,一个相对分子质量为21000的未知蛋白在运动后表达下调在5倍以上,另外有两个点经鉴定均为Myosin-6,在运动后表达量相反。这些蛋白质属于收缩蛋白、能量代谢酶、分子伴侣等。结论:递增运动负荷训练后力竭时,大鼠心室肌蛋白质组明显地发生了反应。运动后"缺失"和下调的蛋白质点与心肌收缩的调控和能量代谢的方式转变以及细胞的应激反应有关,其中,成功筛选出6种在运动医学领域尚未涉足的、具有运动应激特点的目标蛋白质。  相似文献   
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Neurofibromatosis type 2 is caused by mutations in the NF2 tumor suppressor gene. The NF2 gene encodes a 595‐aminoacid protein, presumably functioning as a membrane‐organizing element. Theoretically, the majority of mutations found in the NF2 gene should lead to a truncated protein product. Using immunoprecipitation with an antibody raised to N‐terminal sequences of the NF2 protein, the authors sought to demonstrate the presence of truncated NF2 proteins in tumors. From 17 of 19 tumors (14 meningiomas and five schwannomas), 12 of which have previously been shown to harbor truncating NF2 mutations, wild‐type NF2 protein was immunopreci‐pitated. From two tumors no protein was precipitated. Truncated NF2 proteins were not observed. The authors conclude that mutant NF2 proteins are unstable and undergo accelerated degradation.  相似文献   
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Fairbanks  VF; Nepo  AG; Beutler  E; Dickson  ER; Honig  G 《Blood》1980,55(2):216-220
Two large and unrelated families were investigated for hereditary nonspherocytic hemolytic anemia associated with deficiency of erythrocyte glucose-6-phosphate dehydrogenase (G6PD). In both families, the kinetic and electrophoretic features of the G6PD variants resembled those of G6PD Chicago. Further investigation revealed that members of one of these families previously had been characterized as having the G6PD variants Chicago and Cornell. However, it is clear that each of these terms has been applied to the same variant in this single large kindred. In the second family, we describe a newly identified variant with unique characteristics, which we have designated G6PD Pea Ridge. G6PD Pea Ridge resembles G6PD Chicago but differs in electrophoretic mobility and in a few kinetic parameters. It exhibits an unusually high Ki for NADPH and thus appears to be insensitive to product inhibition. As other cases previously considered to be the Chicago variant become more fully characterized, this probably will be shown to be a heterogeneous group of variants.  相似文献   
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Marfan Syndrome (MFS) is an autosomal dominant disorder of the connective tissue due to mutations of Fibrillin-1 gene (FBN1) in more than 90% of cases and Transforming Growth Factor-Beta-Receptor2 gene (TGFB2R) in a minority of cases. Genotyping is relevant for diagnosis and genotype-phenotype correlations. We describe the FBN1 genotypes and related phenotypes of 81 patients who were referred to our attention for MFS or Marfan-like phenotypes. Patients underwent multidisciplinary pertinent evaluation in the adult or paediatric setting, according to their age. The diagnosis relied on Ghent criteria. To optimise DHPLC analysis of the FBN1 gene, all coding regions of the gene were directly sequenced in 19 cases and 10 controls: heterozygous amplicons were used as true positives. DHPLC sensitivity was 100%. Then, DHPLC was used to screen 62 other cases. We identified 74 FBN1 mutations in 81 patients: 64 were novel and 17 known. Of the 81 mutations, 41 were missense (50.6%), 27, either nonsense or frameshift mutations and predicted a premature termination codon (PTC) (33%), 11 affected splice sites (13.6%), and two predicted in-frame deletions (2.5%). Most mutations (67.9%) occurred in cbEGF-like modules. Genotype was clinically relevant for early diagnosis and conclusion of the diagnostic work-up in patients with incomplete or atypical phenotypes.  相似文献   
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