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Rodgers  GM; Broze  GJ Jr; Shuman  MA 《Blood》1984,63(2):434-438
Previously, we showed that cells derived from nonvascular tissues initiate clotting primarily by markedly increasing the activity of coagulation factor VII. Cells derived from vascular tissue do not normally exhibit this property (tissue factor activity). In this study, we have characterized the relationship between the tissue factor activity of cultured cells derived from normal tissues and the number of receptors they possess for coagulation factor VII. Only cultured nonvascular cells expressed tissue factor activity or possessed receptors for 125I-factor VII. Fetal lung cells, the nonvascular tissue with the largest amount of procoagulant and tissue factor activity, possessed the most receptors for 125I-factor VII (880,000/cell). Bovine corneal endothelial cells, the nonvascular tissue possessing the fewest number of receptors (2,400/cell), had the least amount of procoagulant or tissue factor activity. The affinity of nonvascular cells for 125I- factor VII varied for the cells studied (Kd congruent to 1.3-90 X 10(- 10) M). Vascular cells expressed no tissue factor activity, nor did they bind 125I-factor VII. 125I-factor VII and unlabeled factor VII bound to cells had identical procoagulant activities. These results indicate that the ability of cultured cells to initiate coagulation may be regulated in part by the number of receptors they possess for factor VII.  相似文献   
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Plantaris muscle injury: evaluation with MR imaging   总被引:3,自引:0,他引:3  
Helms  CA; Fritz  RC; Garvin  GJ 《Radiology》1995,195(1):201
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To determine the relation between basic clinical characteristics and resource utilisation in paediatric intensive care, an open prospective study was performed. Resource utilisation was expressed using the therapeutic intervention score system (TISS) and length of stay (LOS), from which total resource utilisation per admission (TISSTOT) and average daily resource utilisation (TISSMEAN = TISSTOT/LOS) were obtained. Overall 593 admissions, totalling 3130 days, were included. Mortality was 8.4% and non-survivors accounted for 14.1% of overall resource utilisation. In non-survivors, TISSTOT and TISSMEAN were higher, whereas LOS was not different from survivors'. Severity of illness, surgical status, significant chronic comorbidity, emergency admission, and transfer status constituted the major predictive determinants of TISSTOT (r2 = 0.19) and TISSMEAN (r2 = 0.45) in multiple regression analysis. High resource utilisation in high risk patients was probably warranted, as effectiveness of prolonged intensive treatment was demonstrated. It is concluded that TISSTOT and TISSMEAN are appropriate, non-monetary measures of resource utilisation, a considerable proportion of which are determined by a concise set of basic clinical characteristics.  相似文献   
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苄基四氢巴马汀(BTHP)使苯福林对大鼠肛尾肌和兔主动脉条作用的累积量效曲线平行右移,最大反应不压低,pA2值分别为5.86和5.8,但对甲氧明和B-HT920升高DP作用的量效曲线无明显影响。BTHP可使异丙肾上腺素和组胺正性频率作用的量效曲线非平行右移,最大反应压低。BTHP还能明显缩短大鼠再灌流所致心律失常的持续时间。结果提示,BTHP对α1受体的阻断及对β和H2受体的非竞争性拮抗作用可能与该药抗心律失常作用有部分关系但并非其主要机理。  相似文献   
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Patients with dilated stenoses and recanalized occlusions were evaluated to assess the initial and long-term results of percutaneous transluminal angioplasty (PTA) in the femoropopliteal artery. The follow-up period was at least 1 year. The initial success rate was 84% (128/164). The initial results were influenced by the radiologist's experience, catheter selection, and type of lesion. The 5- and 7-year cumulative patency rates were 70% and 60%. There was no difference in long-term patency between initially successful stenoses and short (less than 3 cm) occlusions. Both the morphology and location of the stenotic lesion influenced the long-term results. Although many factors influence the initial and long-term success rate, results of this study justify PTA in the femoropopliteal artery. Patients with localized stenoses and short occlusions are best suited for this treatment.  相似文献   
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