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排序方式: 共有796条查询结果,搜索用时 31 毫秒
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A genetic polymorphism in connexin 37 as a prognostic marker for atherosclerotic plaque development 总被引:8,自引:0,他引:8
M. Boerma L. Forsberg L. Van Zeijl R. Morgenstern U. De Faire C. Lemne D. Erlinge T. Thulin Y. Hong & I. A. Cotgreave 《Journal of internal medicine》1999,246(2):211-218
BACKGROUND AND OBJECTIVES: Atherosclerosis is a multifactorial disease, in part characterized by chronic inflammatory changes in the vessel wall and loss of normal physical and biochemical interactions between endothelial cells and smooth muscle cells. Previous studies [Hu J., Cotgreave IA. J Clin Invest; 99: 1-5] have provided molecular links between inflammation and myoendothelial communication via gap junctions, suggesting that these structures may be important in the development of the atherosclerotic vessel phenotype. In order to strengthen this premise, the aim of the present work was to probe for structural polymorphisms in connexin 37, a gap junctional protein uniquely expressed in endothelial cells, and to assess for potential genotypic segregation in individuals displaying atherosclerotic plaque. METHODS AND RESULTS: Computer-based comparisons of Expressed Sequence Tags (ESTs) predicted a polymorphism in the human gap junctional protein connexin 37 (cx37). The C1019-T mutation results in a proline to serine shift at codon 319 (cx37*1-cx37*2). A Restriction Fragment Length Polymorphism (RFLP) assay, involving the insertion of a novel Drd I cleavage site in the proline variant revealed a statistically significant over-representation of the cx37*1 allele in association with atherosclerotic plaque-bearing individuals (Odds-ratio for the homozygote = 2.38, Chi2 = 7.693, P = 0.006), in comparison to individuals lacking plaque, irrespective of a history of hypertension. CONCLUSIONS: These data suggest that the C1019-T polymorphism in cx37 may provide 'single gene marker', which could be useful in assessing atherosclerotic plaque development, particularly in cardiovascular risk groups such as those with borderline hypertension. 相似文献
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Specificity of autoantibodies in autoimmune thrombocytopenia 总被引:12,自引:5,他引:12
In 42 patients with autoimmune thrombocytopenia (AITP) and a positive direct platelet suspension immunofluorescence test (PSIFT), the antigenic specificity of the autoantibodies was studied. Because the autoantibodies were often not detectable in the serum and additional HLA antibodies may disturb the reaction pattern with the platelet panel, we used eluates prepared from the patients' platelets for this study. Thirty-five patients had antibodies equally reactive with normal platelets, irrespective of their antigenic make-up, but not with the platelets from two Glanzmann's disease patients. Absorption and elution experiments in two patients showed that his was probably not due to the presence of a combination of anti-Zwa and anti-Zwb antibodies. Thus, the majority of autoantibodies against platelets seems to be directed against antigenic determinants not present on Glanzmann's disease platelets, but perhaps located on the platelet-membrane glycoproteins IIb and/or IIIa. In ten patients, antibodies of no, or still unknown, specificity were detected. Three of these had additional antibodies not reactive with the platelets of the two Glanzmann patients. 相似文献
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Jan Siert K. Reinders Dirk J. Gouma Dirk T. Ubbink Bert van Ramshorst Djamila Boerma 《World journal of surgery》2014,38(9):2403-2411
Background
Choledochocystolithiasis can be managed by endoscopic retrograde cholangiopancreaticography (ERCP) or laparoscopically by transcystic (TC) or transductal (TD) stone extraction.Objective
The aim of this study was to systematically review safety and effectiveness of combined endoscopic/laparoscopic management versus total laparoscopic management for choledochocystolithiasis with specific emphasis on TC versus TD stone extraction.Methods
MEDLINE/PubMed, EMBASE, the Cochrane Library, and clinicaltrials.gov were searched systematically to identify trials on combined endoscopic/laparoscopic and total laparoscopic management for choledochocystolithiasis. Laparoscopic common bile duct (CBD) exploration was divided into TD and TC approach. Primary outcomes were successful stone clearance from CBD, postoperative/procedural morbidity, and mortality.Results
Eight randomized trials with 965 patients were included. Successful bile duct clearance varied between 52.6 and 97 % in the ERCP groups, 80.4 and 100 % in the TC groups, and 58.3 and 100 % in the TD groups. There were more bile leaks after TD stone extraction (11 %) than after ERCP (1 %) and TC stone extraction (1.7 %). Total morbidity varied between 9.1 and 38.3 % in the ERCP groups, 7 and 10.5 % in the TC groups, and 18.4 and 26.7 % in the TD groups. Methodological and statistical heterogeneity among the trials precluded a meaningful meta-analysis.Conclusion
Stone clearance rates are comparable between the three modalities, but TD stone extraction is associated with a higher risk of bile leaks and should only be performed by highly experienced surgeons. TC stone extraction seems a more accessible technique with lower complication rates. If unsuccessful, per- or postoperative endoscopic stone extraction is a viable option. 相似文献77.
FJ Cowan JT Warner FD Dunstan WD Evans JW Gregory HR Jenkins 《Archives of disease in childhood》1997,76(4):325-329
The prevalence of osteopenia in children with inflammatory bowel disease (IBD) is unknown. The effect of nutritional state, disease activity, and steroid therapy on bone mineral content (BMC) of whole body, lumbar spine, and left femoral neck measured by dual energy x ray absorptiometry in 32 children with IBD was assessed by comparison with 58 healthy local school children. Using the control data, a predicted BMC was calculated taking into account bone area, age, height, weight, and pubertal stage. The measured BMC in children with IBD was expressed as a percentage of this predicted value (% BMC). Mean (SD) % BMC was significantly reduced for the whole body and left femoral neck in the children with IBD (97.0 (4.5)% and 93.1 (12.0)% respectively, p < 0.05). Of the children with IBD, 41% had a % BMC less than 1 SD below the mean for the whole body and 47% at the femoral neck. Reduction in % BMC was associated with steroid usage but not with the magnitude of steroid dose, disease activity, or biochemical markers of bone metabolism. In conclusion, osteopenia is relatively common in childhood IBD and may be partly related to the previous use of steroids. 相似文献
78.
Background
The purpose of this study was to determine the test-retest reliability of temporal and spatial gait measurements over a one-week period as measured using an instrumented walkway system (GAITRite®).Methods
Subjects were tested on two occasions one week apart. Measurements were made at preferred and fast walking speeds using the GAITRite® system. Measurements tested included walking speed, step length, stride length, base of support, step time, stride time, swing time, stance time, single and double support times, and toe in-toe out angle.Results
Twenty-one healthy subjects participated in this study. The group consisted of 12 men and 9 women, with an average age of 34 years (range: 19 – 59 years). At preferred walking speed, all gait measurements had ICC's of 0.92 and higher, except base of support which had an ICC of 0.80. At fast walking speed all gait measurements had ICC's above 0.89 except base of support (ICC = 0.79),Conclusions
Spatial-temporal gait measurements demonstrate good to excellent test-retest reliability over a one-week time span.79.
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