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Host kidneys may contribute considerably to hypertension after renal transplantation. Their role in sustaining hypertension is more prominent if glomerulonephritis (GN) than if interstitial nephritis (IN) is the original renal disease. We compared the antihypertensive effect of beta-blockade in IN (n = 10) and GN (n = 19) hypertensive renal transplant recipients with host kidneys in situ with those who had undergone bilateral nephrectomy (BN, n = 10). Pretreatment blood pressures were comparable in BN, IN, and GN patients, being 165 +/- 6/108 +/- 3, 172 +/- 5/104 +/- 3, and 161 +/- 3/104 +/- 1, mmHg, respectively. Blood pressure did not change on beta-blockade in BN patients, whereas it decreased significantly more (P less than 0.001) in GN than in IN patients, changes of mean arterial pressure being -107 +/- 1.0, -14.9 +/- 1.3, and -6.8 +/- 1.6%, respectively. This failure to respond to beta-blockade in patients without host kidneys may be related to low activity of the renin-angiotensin system or to functional denervation of the grafted kidney. Further investigations of this phenomenon may clarify the mechanism of antihypertensive action of beta-blockade as well as the nature of hypertension after renal transplantation.  相似文献   
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Myocardial biopsies were obtained from 27 patients undergoing corrective cardiac surgery for congenital heart disease. Normal hearts of 18 autopsied patients were used as reference. The biopsy material was assessed for desoxyribonucleic acid (DNA) concentration and ploidy profile of cell nuclei in order to quantitate myocardial hypertrophy at the time of operation. DNA-concentration decreased significantly with age (r = -0.76; p less than 0.001). Ploidy profile of myocardial nuclei correlated with age: the relative number of diploid nuclei decreased (r = -0.67; p less than 0.001), the relative numbers of tetraploid and octoploid nuclei increased with age (r = 0.58; p less than 0.01 and r = 0.77; p less than 0.001 respectively). At 8 years of age the patients with congenital heart disease reached myocardial DNA-concentrations comparable with those in normal adult hearts. At higher age the patients with congenital heart disease exceeded normal adult values for myocardial DNA-concentration. These findings are interpreted to represent rapid development of hypertrophy with an early onset, reaching at 8 years of age values observed in normal adult hearts. Quantitation of myocardial hypertrophy by DNA-concentration and ploidy profile of nuclei may offer a means to explain some of the factors of influence on the outcome of corrective cardiac surgery for congenital heart disease in relation to its timing. Our data stress the need for preventing irreversible myocardial damage by timely (surgical) therapy.  相似文献   
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The moderator effect of gender on (i) the relation between adolescents' sexual experience on the one hand; and (ii) their orientations towards the type of relational and emotional commitment that they expect to be present before engaging in a sexual relationship, and (iii) having a steady partner on the other was examined. We hypothesized that the relations between these facets would be stronger for women. We utilized a random sample of 253 British adolescents interviewed twice with a 1-year interval LISREL multigroup analysis with mean structures was used to test the hypotheses, thus offering the opportunity of detecting moderator as well as main effects of gender. Differential effects of emotional and relational commitment and having a steady partner relationship on sexual experience supported the hypotheses.  相似文献   
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Connexin-containing gap junctions play an essential role in vertebrate development. More than 20 connexin isoforms have been identified in mammals. However, the number identified in Xenopus trails with only six isoforms described. Here, identification of a new connexin isoform from Xenopus laevis is described. Connexin40.4 was found by screening expressed sequence tag databases and carrying out polymerase chain reaction on genomic DNA. This new connexin has limited amino acid identity with mammalian (<50%) connexins, but conservation is higher (approximately 62%) with fish. During Xenopus laevis development, connexin40.4 was first expressed after the mid-blastula transition. There was prominent expression in the presomitic paraxial mesoderm and later in the developing somites. In adult frogs, expression was detected in kidney and stomach as well as in brain, heart, and skeletal muscle. Ectopic expression of connexin40.4 in HEK293 cells, resulted in formation of gap junction like structures at the cell interfaces. Similar ectopic expression in neural N2A cells resulted in functional electrical coupling, displaying mild, asymmetric voltage dependence. We thus cloned a novel connexin from Xenopus laevis, strongly expressed in developing somites, with no apparent orthologue in mammals.  相似文献   
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Journal of Occupational Rehabilitation - Purpose Health problems among employees with a lower socioeconomic position (SEP) often result from an interplay of problems on multiple life domains....  相似文献   
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Human bone allografts can induce T cells with high affinity for donor antigens   总被引:12,自引:0,他引:12  
We analysed the cellular immune response in ten transplantations of different massive bone allografts, of which five had a poor clinical outcome. Cytotoxic T lymphocytes (CTL) and T helper lymphocytes (TH) against mismatched donor antigens were found in all patients. More importantly, CTL with a high affinity for donor antigens were found in five cases. High-affinity CTL need no CD8 molecule to stabilise the antigen binding and are strongly associated with rejection of heart and corneal transplants. Even after removal of most of the bone-marrow cells, we found high-affinity CTL and high TH frequencies. This T-cell response could be detected over a period of years. We conclude that frozen bone allografts can induce high-affinity donor-specific CTL. The present assay allows qualification and quantification of the levels of CTL and TH in the blood. This approach may be helpful in studying the effect of the immune response on the outcome of the graft.  相似文献   
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Blood pressure and proteinuria are important determinants of progressive renal failure in patients with renal diseases. In a 53-year-old man with hypertension and nephrotic-range proteinuria, lowering the blood pressure to a value of 125/75 mmHg resulted in a disappearance of the proteinuria. Recent literature data indicate that the treatment of blood pressure in patients with proteinuria, with emphasis on the benefits of reaching a blood pressure target of 125/75 mmHg and the use of angiotensin-converting enzyme inhibitors, may lead to a serious improvement in their prognosis.  相似文献   
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