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11.
M C van Dam-Mieras A D Muller V W van Hinsbergh W J Mullers P H Bomans C A Bruggeman 《Thrombosis and haemostasis》1992,68(3):364-370
The report describes the effect of an in vitro infection of human umbilical vein endothelial cells with human Cytomegalovirus (CMV). The parameters studied are cellular procoagulant activity, secretion of plasminogen activator inhibitor (PAI-1) and urokinase-type plasminogen activator (u-PA), activation and internalization of factor X and Merocyanine 540 staining. The infection does not result in an increase in PAI-1 and u-PA secretion, but it brings about a procoagulant response, which is relatively rapid compared to the tissue factor mediated response induced by inflammatory mediators. The time course and the coagulation factor dependency suggest a facilitated interaction of coagulation factors on the surface of infected cells. Chromogenic activity measurements after the addition of purified factor X and electron microscopic examination of the cells after addition of colloidal gold-factor X conjugates both point to an internalization of factor X and/or Xa after interaction with the endothelial cell surface. Merocyanine 540 staining suggests that CMV infection leads to membrane perturbations. 相似文献
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M J Busby M F Bellantoni J D Tobin D C Muller S D Kafonek M R Blackman R Andres 《Journal of the American Geriatrics Society》1992,40(5):497-502
OBJECTIVE: To determine the separate and interactive effects of age, phase of the menstrual cycle, menopausal hormone status, body fat mass, and regional fat distribution on glucose tolerance in healthy women. DESIGN: Retrospective study. SETTING: The Baltimore Longitudinal Study of Aging. PATIENTS: Two hundred sixty healthy women aged 22-89 years. MEASUREMENTS: Plasma levels of estradiol and progesterone, body mass index (BMI), waist-to-hip ratio (WHR), and plasma glucose values in the fasting state (FPG) as well as 120 minutes after 40 gm/m2 of oral glucose (G120) were measured for each participant. RESULTS: We found a progressive decline in oral glucose tolerance of 0.4 mM (6.7 mg/dL)/decade at G120) in women from early to late adult years, with no relationship to phase of the menstrual cycle and no abrupt change associated with the menopause. Multiple regression analysis revealed significant, independent effects of BMI and WHR on FPG and G120. The influence of age (P less than 0.01) on G120 was stronger than that of the BMI or WHR (P less than 0.05). There was no significant relationship between the levels of endogenous sex hormones and glucose tolerance after adjustments for age, BMI, and WHR. However, women taking oral contraceptives, but not those receiving postmenopausal replacement therapy, did exhibit mildly elevated G120 values. CONCLUSIONS: Age per se, and to a lesser extent BMI and WHR, but not levels of endogenous sex steroids, contribute to the physiological decline in glucose tolerance in older women. 相似文献
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M. P. Muller S. E. Richardson A. McGeer L. Dresser J. Raboud T. Mazzulli M. Loeb M. Louie 《European journal of clinical microbiology & infectious diseases》2006,25(4):230-237
The clinical presentation of SARS is nonspecific and diagnostic tests do not provide accurate results early in the disease course. Initial diagnosis remains reliant on clinical assessment. To identify features of the clinical assessment that are useful in SARS diagnosis, the exposure status and the prevalence and timing of symptoms, signs, laboratory and radiographic findings were determined for all adult patients admitted with suspected SARS during the Toronto SARS outbreak. Findings were compared between patients with laboratory-confirmed SARS and those in whom SARS was excluded by laboratory or public health investigation. Of 364 cases, 273 (75%) had confirmed SARS, 30 (8%) were excluded, and 61 (17%) remained indeterminate. Among confirmed cases, exposure occurred in the healthcare environment (80%) or in the households of affected patients (17%); community or travel-related cases were rare (<3%). Fever occurred in 97% of patients by the time of admission. Respiratory findings including cough, dyspnea and pulmonary infiltrates evolved later and were present in only 59, 37 and 68% of patients, respectively, at admission. Direct exposure, fever on the first day of illness, and elevated temperature, pulmonary infiltrates, lymphopenia and thrombocytopenia at admission were associated with confirmed cases. Rhinorrhea, sore throat, and an elevated neutrophil count at admission were associated with excluded cases. In the absence of fever or significant exposure, SARS is unlikely. Other clinical, laboratory and radiographic findings further raise or lower the likelihood of SARS and provide a rational basis for estimating the likelihood of SARS and directing initial management. 相似文献
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In a retrospective study of 137 biopsy specimens of skin from 137 patients (69 men and 68 women) that had been obtained between 1972 and 1989 at our institution and that had perivascular and periappendageal lymphocytic infiltrates characteristic of those described as benign lymphocytic infiltrate (BLI), we determined the specificity of the histologic diagnosis and the correlation with clinical data. The final diagnoses, based on clinical and laboratory data and histologic findings, were BLI (59), possible BLI (7), lupus erythematosus (LE) (12), possible LE (7), procainamide-induced LE (1), insect bites (9), possible insect bites (3), polymorphous light eruption (4), lymphocytoma (4), urticaria (4), and indeterminate or miscellaneous diagnoses (27). BLI is a clinical and histologic syndrome that can be heterogeneous in origin. We recommend careful evaluation to exclude other disorders such as LE, polymorphous light eruption, lymphocytoma, and insect bites. Direct immunofluorescence microscopy and immunophenotypic studies may help distinguish BLI from LE. 相似文献