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51.
Summary: Sixty-nine renal allograft recipients were randomized to two immunosuppressive regimens: 35 patients received cyclosporine A and prednisolone (PC) while 34 patients received low dose cyclosporine A, prednisolone and short term azathioprine (PCA). the data of 66 patients (34 in PC and 32 in PCA groups) were analysed. the median follow-up periods were 62 months for the PC group and 60 months for the PCA group. There was no difference in graft survival between the two groups but five patients died in the PC group compared to none in the PCA group (graft survival: 88 vs 90% at 1 year and 82 vs 82% at 5 years, P = not significant at any time point; patient survival: 90 vs 100% at 1 year and 88 vs 100% at 5 years, P = 0.05 at 5 years). There was a trend for patients in the PCA group to develop earlier and more frequent rejections (not significant; P = 0.106 and P = 0.062, respectively). There were also more episodes of acute cyclosporine A nephrotoxicity and cytomegalovirus (CMV) infection in the PC group. the mean serum creatinine at 5 years was significantly higher in the PCA group when compared to the PC group (179.8 ± 76.5 μmol/L vs 154.7 ± 41.0 μmol/L; P =0.05). We found that both therapeutic regimens were effective in preventing renal allograft rejections. However, double therapy was associated with higher patient mortality secondary to infection. Patients on triple therapy, on the other hand, were more prone to develop rejections in the early post-transplant period and were associated with less favourable renal function in the long run.  相似文献   
52.

Background  

Smoking cessation interventions in pregnancy could influence a woman's social behaviour and her partner's smoking behaviour, but this has not been examined in any published randomized trials.  相似文献   
53.
Telomerase and the Aging Cell: Implications for Human Health   总被引:1,自引:0,他引:1  
Fossel  Michael 《JAMA》1998,279(21):1732-1735
Michael Fossel, MD, PhD

JAMA. 1998;279:1732-1735.

Recent research has shown that inserting a gene for the protein component of telomerase into senescent human cells reextends their telomeres to lengths typical of young cells, and the cells then display all the other identifiable characteristics of young, healthy cells. This advance not only suggests that telomeres are the central timing mechanism for cellular aging, but also demonstrates that such a mechanism can be reset, extending the replicative life span of such cells and resulting in markers of gene expression typical of "younger" (ie, early passage) cells without the hallmarks of malignant transformation. It is now possible to explore the fundamental cellular mechanisms underlying human aging, clarifying the role played by replicative senescence. By implication, we may soon be able to determine the extent to which the major causes of death and disability in aging populations in developed countries—cancer, atherosclerosis, osteoarthritis, macular degeneration, and Alzheimer dementia—are attributable to such fundamental mechanisms. If they are amenable to prevention or treatment by alteration of cellular senescence, the clinical implications have few historic precedents.

  相似文献   

54.

Background

Medical intelligence of disease vectors deals with understanding vector distribution and control.

Methods

An entomological baseline survey using standard vector sampling techniques was done as a pilot study to map the vectors of defence importance in two cantonments of Pune with a view to establish a vector databank and impart training to armed forces personnel in vector surveillance.

Result

The project trained 142 armed forces personnel in surveillance techniques in three years. Seventeen species of mosquitoes comprising of eight vector species were collected. Three other vectors viz. Rhipicephalus sanguineus, Xenopsylla cheopis and Leptotrombidium deliense are reported.

Conclusion

The study emphasizes the need for vector mapping /surveillance in each area for preventing morbidity and mortality amongst troops. It also focuses on indigenous fabrication of vector sampling tools and training of personnel for capacity building which in turn will enable such surveys to be undertaken in other units and deployment areas.Key Words: Leptotrombidium, Mosquitoes, Rhipicephalus, Surveillance, Xenopsylla  相似文献   
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The objective of this study was to describe patterns and predictors of work absence in the prospective, community-based Maine Carpal Tunnel Study. Three hundred fifteen patients with carpal tunnel syndrome (CTS) were recruited from physicians' offices throughout Maine. The patients completed questionnaires at entry and after 6, 18, and 30 months. The questionnaires included scales measuring symptom severity, functional status, general and mental health status, exposure to physical stressors, work status, and other indicators. The analyses examined univariate and multivariate correlates of work absence. The mean age was 43, 72% of subjects were female, 71% underwent carpal tunnel release, and 45% were receiving Workers' Compensation. Fifty-two percent worked in managerial or technical occupations, 15% in service occupations, and 13% in heavy labor or machine operation. Forty-five percent of patients changed jobs or were absent from work (aside from postoperative recovery) during the 30-month follow-up. In multivariate logistic regression models, correlates of work absence at 18 months included worse functional status of the hand at study entry and at 6-month follow-up, involvement of an attorney at the time of enrollment (P < 0.002 for each), and work absence at 6 months (P = 0.03). Worse upper extremity functional status and having a contested Workers' Compensation claim are critical predictors of work absence and should be principal targets of interventions to reduce work disability in CTS. Am. J. Ind. Med. 33:543–550, 1998. © 1998 Wiley-Liss, Inc.  相似文献   
57.
Needle biopsy of renal allografts: comparison of two techniques   总被引:2,自引:0,他引:2  
Two techniques for renal allograft biopsy were retrospectively evaluated to compare relative safety and efficacy. After ultrasound (US) localization of the kidney and biopsy with a hand-held 14-gauge cutting needle, an adequate specimen was obtained in 74 of 77 cases (96%). Major complications occurred in six of these 77 cases (8%). One hundred four biopsies were performed by using a smaller 18-gauge cutting needle with a spring-loaded biopsy "gun" and real-time US guidance. With this newer technique, specimens adequate for diagnosis were obtained in 99 biopsies (95%). There was a single major complication with this technique (1%). The 18-gauge needle with real-time US guidance yields comparably adequate specimens with a lower frequency of complications.  相似文献   
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Parathyroid hormone secretion is negatively regulated by a 7- transmembrane domain, G-protein coupled Ca(2+)-sensing receptor. We hypothesized that activating mutations in this receptor might cause autosomal dominant hypoparathyroidism (ADHP). Consistent with this hypothesis, we identified, in two families with ADHP, heterozygous missense mutations in the Ca(2+)-sensing receptor gene that cosegregated with the disorder. None of 50 normal controls had either mutation. We also identified a de novo, missense Ca(2+)-sensing receptor mutation in a child with severe sporadic hypoparathyroidism. The amino acid substitution in one ADHP family affected the N-terminal, extracellular domain of the receptor. The other mutations involved the transmembrane region. Unlike patients with acquired hypoparathyroidism, patients with these mutations had hypercalciuria even at low serum calcium concentrations. Their greater hypercalciuria presumably reflected activation of Ca(2+)-sensing receptors in kidney cells, where the receptor negatively regulates calcium reabsorption. This augmented hypercalciuria increases the risk of renal complications and thus has implications for the choice of therapy.   相似文献   
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