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Atrial natriuretic peptide(s) (ANP), are thought to be released from the cardiac atria in response to distension. If decreased effective circulating blood volume is important in pathogenesis of ascites, plasma ANP levels would be expected to be decreased in ascitic subjects because of decreased atrial distension. To test this hypothesis, we measured plasma ANP by competitive radioimmunoassay in three groups of fasted, supine hospitalized subjects: nine noncirrhotic control subjects, 12 cirrhotics without ascites, and 17 cirrhotics with moderate to marked ascites. Immunoreactive plasma ANP concentrations were 195 +/- 41, 171 +/- 31, and 137 +/- 34 pg/ml (m +/- SD), respectively, in the three groups. The mean concentration in the group with cirrhosis and ascites was significantly (p less than or equal to 0.01) les than those of the other two groups, which did not differ from one another. These results support the concept that decreased effective circulating volume plays a role in pathogenesis of cirrhotic ascites, and that a relative deficiency of ANP plays a role in the sodium retention of decompensated cirrhosis.  相似文献   
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Pharmacogenomics of blood pressure response to antihypertensive treatment   总被引:5,自引:0,他引:5  
PURPOSE IDENTIFICATION: Inter-individual variability in blood pressure response to treatment is well documented, but a clinically useful means to distinguish responders from non-responders has been elusive. With the advent of new technologies and genomic knowledge, more investigators are seeking to identify genetic determinants of blood pressure response to therapy. STUDY SELECTION: We identified studies of candidate polymorphisms from an initial PubMed search using the MESH terms 'Hypertension: Drug Therapy' and 'Genetics' or 'Pharmacogenetics', limiting results to English-language publications on studies in human adults. We further identified specific polymorphisms of interest noted in earlier reviews and performed additional PubMed searches based on these candidate genes. Pertinent studies were further extracted from the references of studies already identified. We focused on clinical trials that measured blood pressure response to a medication or class of medications over a minimum of 4 weeks. DATA EXTRACTION: We evaluated studies looking at blood pressure response to commonly used classes of antihypertensive medications by major genetic variants. RESULTS OF ANALYSIS: Although many studies show that blood pressure response to a given class of antihypertensive medications varies by genotype for different polymorphisms, none of the genotypes identified consistently predicted blood pressure response. CONCLUSIONS: Common variants may influence response to diuretics, beta-blockers, angiotensin-converting enzyme inhibitors, and angiotensin receptor blockers, but studies of polymorphisms have generally yielded conflicting results. The inclusion of pharmacogenomic studies in large clinical trials and other more innovative investigative methods may provide greater clarity of the potential role for genotyping in the treatment of patients with hypertension.  相似文献   
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Parameterization of the ST-segment is used as a tool for risk stratification for patients to suffer from ventricular tachycardia. This parameterization is performed in terms of Principal Component Analysis (PCA) applied on multichannel magnetocardiographic (MCG) recordings. 55-channel MCG was recorded from 14 normal persons, 10 patients with CHD, 14 patients with MI, and six patients with VT. We found a significantly (p?<?0.05) lower PCA-score in patients with MI compared to normals. The lowest PCA-score was found in VT patients. Significant differences can be found between VT patients and normals and also between VT patients and CHD patients.  相似文献   
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Two B-cell lines, 2F7 and 10C9, were established by single cell cloning from biopsies obtained from two acquired immune deficiency syndrome patients with Burkitt's lymphoma. Representation of the original tumors was verified by demonstration of (1) identical biallelic rearrangement of Ig genes for 2F7 and (2) shared idiotype for 10C9. Both cell lines displayed cell-surface Ig and secreted Ig (IgM lambda for 2F7, IgM kappa for 10C9). IgMs from both cell lines immunoprecipitated actin; in addition, 2F7 IgM lambda immunoprecipitated recombinant human immunodeficiency virus type 1 (HIV-1) gp 160. 2F7 IgM lambda did not react with other autoantigens (double-stranded and single-stranded DNA, actin, bovine serum albumin, IgG), whereas 10C9 IgM kappa reacted with human IgG. The 2F7 IgM heavy-chain variable region (VH) showed a 95% nucleotide homology with a previously sequenced VHIII germline gene, hv3019b9, whereas the 10C9 IgM VH showed a 95% homology with a previously sequenced VHIV germline gene, VH4.21. Use of minimally modified VH genes and demonstration of reactivity with chronically present antigens (ie, actin, HIV-1 gp 160, or human IgG) suggests that B cells in HIV-1-infected individuals proliferating in response to chronic antigenic stimulation may be at increased risk for lymphomagenesis.  相似文献   
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目的:神经断端保留小间隙的静脉桥接模拟神经外膜形成神经再生室,为周围神经再生创造了良好的生理环境,从而保证神经束的良好对合。实验采用部分脱乙酰甲壳质作为套管材料,用小间隙桥接方法修复坐骨神经损伤,观察套管内的神经再生情况,并与传统外膜缝合法进行比较。方法:实验于2001-01/2002-10在北京大学人民医院创伤骨科实验室完成。①主要材料:实验所用中空圆柱形套管为北京大学人民医院与中国纺织科学院共同发明的一种部分脱乙酰甲壳质生物套管(专利号:01136314.2)。实验中所用套管尺寸为:管长4 mm,壁厚0.1 mm,内径1.5 mm。②实验动物:健康成年雄性SD大鼠20只,随机分成2大组,每组10只,每一大组全部10只动物的左腿坐骨神经为一组,右腿坐骨神经为另一组,每组10根坐骨神经。另取5只同样大鼠双侧坐骨神经未做处理作为正常对照组。③实验方法:外膜原位缝合组:切断坐骨神经,显微镜下神经外膜原位缝合;生物套管小间隙原位桥接组:切断坐骨神经,显微镜下小间隙套管桥接;断端旋转180°外膜缝合组:切断坐骨神经,显微镜下远端旋转180°后,神经外膜缝合;断端旋转180°生物套管小间隙桥接组:切断坐骨神经,显微镜下远端旋转180°后,小间隙套管桥接。④实验评估:术后第7,14,21,28,42天取坐骨神经,进行免疫组织化学染色及观察。结果:再生神经延套管中央走行,7 d时已有部分纤维通过2 mm间隙,14 d时有髓纤维数量明显多于近端。21 d后,套管组与原位外膜组新生有髓神经纤维数相近。再生纤维胞核数量较多,髓鞘纤细。套管结构完整。结论:此种部分脱乙酰甲壳质生物套管内的再生神经连续、整齐,髓鞘完整,其神经再生情况好于传统外膜缝合法。  相似文献   
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CALLA-positive myeloma: an aggressive subtype with poor survival   总被引:5,自引:0,他引:5  
Durie  BG; Grogan  TM 《Blood》1985,66(1):229-232
Detailed immunotyping was carried out on 21 direct myeloma bone marrow aspirates and eight human myeloma cell lines. Four previously untreated common acute lymphoblastic leukemia antigen (CALLA)-positive myeloma patients were identified and six of eight cell lines (75%) were also positive. CALLA positivity, as part of an immature B phenotype, was found to correlate with very aggressive clinical disease: median survival six months v 56 months for the CALLA-negative group.  相似文献   
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