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排序方式: 共有1337条查询结果,搜索用时 15 毫秒
1.
Preliminary evidence for a role of apolipoprotein E alleles in identifying haemodialysis patients at high vascular risk 总被引:1,自引:0,他引:1
Olmer M; Renucci JE; Planells R; Bouchouareb D; Purgus R 《Nephrology, dialysis, transplantation》1997,12(4):691-693
Conventional risk factors have very low predictive power in identifying
haemodialysis patients at high risk of vascular accidents. A role for
apolipoprotein E isotypes was looked for in a small, but rigorously
defined, cohort of longterm haemodialysis patients. In individuals with
high vascular risk, as identified by higher common carotid intima/media
thickness, we found an excess of apolipoprotein E4 alleles. This
preliminary result requires confirmation in large patient cohorts.
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B Huser G Thiel M Oberholzer T Beveridge L Bianchi M J Mihatsch J Landmann 《Transplantation》1992,54(1):65-69
Twelve consecutive first cadaveric kidney transplant recipients received cyclosporine G (CsG)(initial dose 12 mg/kg per day) as basic immunosuppressive treatment along with prednisone (initial dose 0.5 mg/kg per day) for the first three months after transplantation. Thereafter CsG was replaced by Sandimmun (cyclosporine, CsA). Evaluation of the immunosuppressive efficacy and assessment of possible side effects of CsG was made and compared with the results in 38 historical control patients starting with the same dose of CsA as part of the same immunosuppressive dosage schedule. Statistically, there was no difference in patient survival at three (91% in CsG group versus 95% in CsA group) and twelve months (91% in CsG group versus 92% in CsA group), or in graft survival at three (75% in CsG group versus 89% in CsA group) and twelve months (75% in CsG group versus 84% in the CsA group). At equivalent oral doses of CsG and CsA significantly higher blood levels of CsG were observed (2P less than 0.05). Nephrotoxicity assessed by graft biopsy could be demonstrated to a similar extent in both groups, whereas hepatotoxicity was more pronounced during CsG treatment. Sequential measurements of bilirubin revealed a significant increase in all patients but median values were significantly higher in the CsG patients. A pronounced and concordant elevation of liver enzymes occurred during CsG treatment in three out of 12 patients. Liver biopsies performed in these patients revealed histological alterations consistent with toxic liver injury. Thus, in human kidney transplant recipients CsG and CsA appeared to be equally immunosuppressive and nephrotoxic but more hepatotoxic. On the basis of this limited experience we conclude that in human kidney transplant recipients CsG has no advantage over CsA. 相似文献
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Hodgkin disease: CT of the thymus 总被引:2,自引:0,他引:2
The computed tomography (CT) scans in two groups of patients with Hodgkin disease were reviewed to determine the frequency of thymic enlargement. In 50 CT scans from 50 patients with evidence of thoracic disease on CT scans who were examined for primary staging, the thymus was enlarged in 15 of 50 (30%). Fifty CT scans were obtained from 44 patients at the time of 50 separate episodes of known or suspected relapse. Relapse occurred in the mediastinum in 12 episodes, lung parenchyma in five, and both sites in one. Thymic enlargement thought to be due to involvement by disease was present in seven of 18 (38%). Mediastinal disease was associated with thymic enlargement in all but one patient in whom a thymic cyst developed after radiation therapy. Differentiation of thymic enlargement from enlarged superior mediastinal lymph nodes was easily made in all but two patients. Thymic enlargement in the absence of lymph node enlargement may indicate a different disease, since isolated Hodgkin disease of the thymus is uncommon. Primary thymic tumor should be considered initially, whereas after treatment, rebound hyperplasia of the thymus may be the cause of enlargement. 相似文献
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Solitary bronchioloalveolar carcinoma: CT criteria 总被引:14,自引:0,他引:14
Kuhlman JE; Fishman EK; Kuhajda FP; Meziane MM; Khouri NF; Zerhouni EA; Siegelman SS 《Radiology》1988,167(2):379-382
The computed tomographic (CT) scans of 30 patients with solitary bronchioloalveolar carcinoma were reviewed. Common features at CT included the peripheral or subpleural location of a pulmonary mass (25 cases), pseudocavitation (18 cases), heterogeneous attenuation (17 cases), irregular margins forming a star pattern (22 cases), and pleural tags (21 cases). Using these CT criteria, four independent observers attempted to identify cases of bronchioloalveolar carcinoma from a larger sample of lung cancers and benign lesions by categorizing a series of test cases into four probability categories. Although the bronchioloalveolar carcinomas were correctly ranked in the two highest probability categories 75% of the time (in 45 of 60 cases), there was considerable overlap with other lung lesions, particularly with adenocarcinoma and large cell undifferentiated carcinoma. However, even though the typical features of bronchioloalveolar carcinoma are not invariable or highly specific, they are characteristic enough to suggest the diagnosis. 相似文献
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A randomized controlled trial of electromagnetic therapy in the primary care management of venous leg ulceration 总被引:1,自引:1,他引:0
OBJECTIVE: The aim was to establish the potential efficacy, tolerabilityand side-effect profile of electromagnetic therapy as an adjunctto conventional dressings in the treatment of venous leg ulcers. METHOD: A prospective, randomized, double blind controlled clinicaltrial was carried out in a dedicated leg ulcer clinic basedin one urban general practice. Nineteen patients with leg ulcersof confirmed venous aetiology were assessed. The main outcomemeasures were rate and scale of venous leg ulcer healing, changesin patient-reported pain levels, quality of life, degree ofmobility, side effect profile and acceptability to patientsand staff. RESULTS: Sixty-eight per cent of patients attending this dedicated clinicachieved improvements in the size of their ulcer (4, 21%, healedfully) and in reduced pain levels (P < 0.05) during the trial,despite the chronicity of ulcer histories. Patients treatedwith electromagnetic therapy at 800 Hz were found at day 50to have significantly greater healing (P < 0.05) and paincontrol (P < 0.05) than placebo therapy or treatment with600 Hz. All patients reported improved mobility at the end ofthe study. The electromagnetic therapy was well tolerated bypatients, with no differences between groups in reporting adverseevents, and proved acceptable to staff. CONCLUSION: Despite the small numbers in this pilot study, electromagnetictherapy provided significant gains in the healing of venousleg ulcers and reduction in pain. Keywords. Electromagnetic therapy, RCT, leg ulcers, primary care. 相似文献
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PlcR1 and PlcR2 are putative calcium-binding proteins required for secretion of the hemolytic phospholipase C of Pseudomonas aeruginosa. 总被引:1,自引:0,他引:1
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A Cota-Gomez A I Vasil J Kadurugamuwa T J Beveridge H P Schweizer M L Vasil 《Infection and immunity》1997,65(7):2904-2913
The plcHR operon of Pseudomonas aeruginosa includes the structural gene for the hemolytic phospholipase C,plcH (previously known as plcS), and two overlapping, in-phase, genes designated plcR1 and plcR2. Hemolytic and phospholipase C (PLC) activities produced by Escherichia coli and P. aeruginosa T7 expression systems were measured in strains carrying both plcH and plcR genes and in strains carrying each gene separately. When plcH was expressed by itself in the E. coli T7 system, the area of the hemolytic zone on blood agar was less than twice the area of growth. By contrast, when plcR was coexpressed with plcH in this system, the area of the hemolytic zone was approximately 10 times that of the area of the growth on blood agar. Native polyacrylamide gel electrophoretic analyses of PlcH activity expressed in either the E. coli or the P. aeruginosa T7 system carrying plcH alone, or along with the plcR genes, suggest that PlcR either posttranslationally alters the physical or biochemical nature of PlcH or releases PlcH from a complex in the cell so that it can be secreted. The hypothesis that PlcR is involved in the secretion of PlcH is supported by the observation that the ratio of extracellular to cell-associated PlcH activity produced by P. aeruginosa strains containing an in-frame deletion in the chromosomal plcR genes is significantly reduced in comparison with this ratio seen with the wild-type parental strain. This defect in the secretion of PlcH can be complemented by the plcR genes in trans. Additional data suggest that PlcR does not directly affect the secretion of the nonhemolytic phospholipase C (PlcN). PlcR is highly similar to a calcium-binding protein (CAB) from Streptomyces erythraeus. PlcR and CAB contain typical motifs (EF hands) characteristic of eucaryotic calcium-binding proteins, including calmodulin. P. aeruginosa naturally produces membrane vesicles (MVs) containing extracellular proteins including PLC. MVs from the PAO1WT strain contained at least 10-fold more PLC specific activity than those isolated from a strain carrying a deletion of plcR (PAO1 deltaR). Immunogold electron microscopy of PAO1WT and PAO1 deltaR whole cells revealed a distribution of PlcH in these strains consistent with the hypothesis that PlcR is required for the secretion of PlcH. 相似文献
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