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There is increasing evidence that pathological changes in the myocardium during chronic heart failure (CHF) are partly regulated through the activation of the renin-angiotensin system (RAS), an effect mediated by the angiotensin II type 1 receptor (AT1R). We examined the expression of cardiac AT1R mRNA in normal (atria, n=7; ventricle, n=3) and end-stage CHF human hearts (atria, n=8; ventricle, n=14). Tissue was snap-frozen immediately after explantation during orthotopic cardiac transplantation; control specimens were obtained from healthy donor hearts rejected for technical reasons. Northern blots of purified total mRNA from each tissue were hybridized with a random primed radiolabeled probe for the coding sequence of AT1R. Stringent conditions were used for both hybridization (5X SSC, 65 degrees C) and washing (0.5X SSC, 0.1% SDS, 65 degrees C) of the membrane. Left and right atrial tissue showed low levels of AT1R mRNA expression in the controls, with statistically significant upregulation of expression in tissue from pathological hearts; CHF atria 1.28+/-0.86 optical density (OD) units, control atria 0.56+/-0.31 OD units, P=0.05 (mean+/-s.d.). There were undetectable levels in ventricles from either control (2/2) or dilated hearts (7/7). The results were independent of the etiology of the heart failure and suggest that increased levels of atrial AT1R mRNA may occur in response to elevated atrial pressures in heart failure.  相似文献   
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We have assessed the specificity of antibodies from the leukemic B cells of five patients with both chronic lymphocytic leukemia and autoimmune hemolytic anemia (CLL-AHA). Leukemic cells from one patient displayed surface immunoglobulin with heavy and light chain isotypes identical to that of the patient's anti-red blood cell (RBC) antibodies, and the leukemic cells secreted antibodies in vitro with anti-RBC activity. However, in the remaining patients, the leukemic cells displayed surface immunoglobulin with light chain isotypes different from that of the patient's anti-RBC antibodies and secreted antibodies in vitro with no detectable anti-RBC activity. Thus, there are two distinct classes of CLL-AHA patients, differentiated by the presence or absence of an anti-RBC antibody-producing leukemic B cell clone. The apparent heterogeneity in the source of pathogenic anti-RBC antibodies may impact the treatment response of the two classes of CLL-AHA patients.  相似文献   
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The described equivalence postulate was confirmed experimentally by examining physiological responses as well as discomfort sensation in a series of predicted equivalent conditions during exercise (congruent to 3 met). ET or the equivalent Ta at 50% RH is a single independent variable that is uniquely related to the mean skin temperature (Tsk), skin wettedness (w), body core temperature (Tcore) and sense of discomfort.  相似文献   
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The excretion and plasma concentrations of radioactivity and chromatographic patterns of radioactive components in plasma and excreta have been compared in rats, dogs and man after oral doses of the hypolipidemic agent isopropyl-[4'-(p-chlorobenzoyl)-2-phenoxy-2-methyl]-propionate (LF 178; procetofene; Lipanthyl?). 2. In rats, 48.1% of a single dose of 25 mg/kg was excreted in the urine, and 48.6% in the faeces. In dogs, 23.1% of a single dose at the same level was excreted in the urine, and 71.8% in the faeces, but 88.1% of a dose of 300 mg to man was excreted in the urine, and only 5.1% in the faeces. Peak levels of radioactivity in the plasma of all three species studied were similar (20--30 mug/ml) after doses at these levels and concentrations declined thereafter with half-lives of 7--24 h in rats and dogs, and 7 h in man. The half-life of radioactivity concentrations in rat plasma was not altered by repeated daily doses for 7 days. 3. Whole-body autoradiography of rats showed that radioactivity was largely associated with the liver, kidneys and gut, which are the organs of biotransformation and excretion, although relatively high levels were present in lungs and blood, and small amounts of radioactivity had a widespread distribution into some peripheral tissues during 2--7 h after dosing. 4. The available chromatographic evidence indicated that the most important biotransformation pathway appeared to be ester hydrolysis to LF 178 acid and formation of water soluble conjugates of this acid. This pathway appeared similar to that of the related drug clofibrate (ethyl p-chlorophenoxyisobutyrate).  相似文献   
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An electron-microscopic study of Herpetomonase sp. (Leptomonas pessoai)   总被引:1,自引:0,他引:1  
The fine structure of the promastigotes of Herpetomonas sp. (Leptomonas pessoai) kept in a defined medium at 28 degrees C is described. This portozoon reveals several features in common with other trypanosomatids. A membrane-bounded organelle measuring 0.2 to 0.8 mum in diameter, similar to that described as peroxisome in Crithidia fasciculata, was also observed. A large cavity, located between the nucleus and the kinetoplast and containing vesicles and small particulate material is discussed in this paper.  相似文献   
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Seven patients with pulmonary regurgitation (PR), normal pulmonary artery (PA) pressures and large left-to-right atrial shunts are reported. Six had secundum atrial septal defects (ASD) and one had anomalous pulmonary venous drainage. These comprised 4% of 180 patients with atrial shunts and normal PA pressures. Pulmonary regurgitation was diagnosed clinically by mid-frequency diastolic decrescendo murmurs beginning after the pulmonic component of the second heart sound, and diagnoses were confirmed by catheterization. In two patients who had serial preoperative catheterizations over 8 and 16 years, PR progressed in one and was present only on the second study in the other. All patients underwent shunt correction, at which time the pulmonic anulus and artery appeared dilated, but the pulmonic valves were normal and did not require revision. In all patients the PR murmur disappeared after shunt correction alone, and on chest X-ray both PA and overall heart size decreased. Although it is known that pulmonary regurgitation occurs with atrial septal defects and pulmonary hypertension, the present study demonstrates that it also occurs with high flow atrial shunts, in which setting it has different implications and is reversible with shunt correction alone.  相似文献   
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The clinical effectiveness of antenatal prednisolone medication (prednisolone hemisuccinate) for the prophylaxis of idiopathic respiratory distress syndrome (IRDS) was studied in 114 premature infants with a gestational age between 28 and 36 weeks. There was a statistically significant difference (chi2 - test, p less than 0,01) between the frequency of IRDS in this group and in another one consisting of 137 premature babies with a nearly identical distribution of gestational age, whose mothers did not get prednisolone before delivery. It could be shown that the time interval between medical induction and delivery should not exceed 2 weeks, since the effect decreases with time. At present prednisolone medication during the fetal period may serve as useful prophylactic measure for IRDS in cases of premature birth. As there are a lot of contraindication against prednisolone and as we do know very much about side effects, it seems necessary to seek for other, less dangerous inductors.  相似文献   
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