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排序方式: 共有823条查询结果,搜索用时 15 毫秒
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IRA Goldsmith FRCS GYH Lip MD MRCP PP Kumar FRCS RL Patel MD FRCS CTh 《International journal of clinical practice》1999,53(1):9-14
To survey the in-hospital morbidity, mortality, length of stay in the intensive therapy unit (ITU) and hospital and quality of life in patients of Indo-Asian origin following coronary artery bypass (CABG) surgery, 345 consecutive patients (mean age 58 years; SD 8.9; range 32-88 years) undergoing primary, isolated CABG were studied. Non-elective CABG was undertaken in 41% of patients. The left anterior descending artery (LAD) was grafted in 89%, although in 30% of these the internal mammary artery (IMA) was not used. Following CABG, the hospital morbidity and mortality was within the expected range, although there was a trend towards higher in-hospital mortality in the Parsonnet low risk group of patients. The length of ITU and hospital stay was not prolonged. Using the SF-36 questionnaire in postoperative patients, low quality of life scores were obtained for six of the eight modalities tested including physical functioning, bodily pain and general health perception. The low quality of life scores and IMA usage in Indo-Asians needs to be addressed. 相似文献
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Dunnick NR; Svetkey LP; Cohan RH; Newman GE; Braun SD; Himmelstein SI; Bollinger RR; McCann RL; Wilkinson RH Jr; Klotman PE 《Radiology》1989,171(1):219-222
Intravenous digital subtraction renal angiography (DSRA) has been compared with conventional angiography only in small, selected series of hypertensive patients. The authors prospectively examined with intravenous DSRA 94 patients at increased risk for renovascular hypertension and compared these studies with conventional angiography. A stenosis of at least one main renal artery was identified with intravenous DSRA in 22 patients and confirmed in 20 patients. No significant stenoses were seen with conventional angiography in any of the 64 patients in whom lesions were not seen with intravenous DSRA. Since inadequate DSRA studies were considered positive for renal artery stenosis, the sensitivity of intravenous DSRA was 100% (25 of 25); specificity, 93% (64 of 69); positive predictive value, 83% (25 of 30); and negative predictive value, 100% (64 of 64). The authors conclude that intravenous DSRA is a sensitive test for identifying stenosis of the main renal arteries and is appropriate to use as a screening test among patients at increased risk for renovascular hypertension. 相似文献
66.
Focal Adhesion Kinase Is Important for Fluid Shear Stress‐Induced Mechanotransduction in Osteoblasts
Suzanne RL Young Rita Gerard‐O'Riley Jae‐Beom Kim Fredrick M Pavalko 《Journal of bone and mineral research》2009,24(3):411-424
Mechanical loading of bone is important for maintenance of bone mass and structural stability of the skeleton. When bone is mechanically loaded, movement of fluid within the spaces surrounding bone cells generates fluid shear stress (FSS) that stimulates osteoblasts, resulting in enhanced anabolic activity. The mechanisms by which osteoblasts convert the external stimulation of FSS into biochemical changes, a process known as mechanotransduction, remain poorly understood. Focal adhesions are prime candidates for transducing external stimuli. Focal adhesion kinase (FAK), a nonreceptor tyrosine kinase found in focal adhesions, may play a key role in mechanotransduction, although its function has not been directly examined in osteoblasts. We examined the role of FAK in osteoblast mechanotransduction using short interfering RNA (siRNA), overexpression of a dominant negative FAK, and FAK?/? osteoblasts to disrupt FAK function in calvarial osteoblasts. Osteoblasts were subjected to varying periods oscillatory fluid flow (OFF) from 5 min to 4 h, and several physiologically important readouts of mechanotransduction were analyzed including: extracellular signal‐related kinase 1/2 phosphorylation, upregulation of c‐fos, cyclooxygenase‐2, and osteopontin, and release of prostaglandin E2. Osteoblasts with disrupted FAK signaling exhibited severely impaired mechanical responses in all endpoints examined. These data indicate the importance of FAK for both short and long periods of FSS‐induced mechanotransduction in osteoblasts. 相似文献
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Blood donation leads to a decrease in natural killer cell activity: a study in normal blood donors and cancer patients 总被引:2,自引:0,他引:2
Transfusion-induced immunosuppression has long been known to be beneficial for organ transplantation patients, but recent retrospective studies suggest that blood transfusions may be detrimental for patients with cancer. If autologous blood is used to avoid immunosuppression, the assumption is that the procedure, involving blood donation, is immunologically neutral. In the present study, this assumption was evaluated by monitoring 33 normal blood donors and 16 colorectal cancer patients before and after donation of 1 (500 mL) and 2 units of blood, respectively. The cancer patients belonged to the autologous arm of a randomized trial in which the effects of allogeneic versus autologous blood on cancer prognosis were studied. The patients donated 2 units of blood with an interval of 3 to 4 days between donations. Flow cytometric analysis revealed that blood donation by normal donors and cancer patients had no effect on the proportion of B, T, and natural killer (NK) cells. Only the total number of lymphocytes was significantly decreased in the normal donors on Day 12 after donation. Blood donation had no significant effect on T-cell function assessed by phytohemagglutinin stimulation in normal donors or in cancer patients donating 2 units of blood. A significant depression of NK cell function (88% and 74% of predonation levels) was observed in normal donors on Days 2 and 5 after donation; on Day 12, the activity was again normal. Colorectal cancer patients had a significantly depressed NK cell activity (54% of predonation activity) on Day 12 after the first donation.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
70.
R. M. SCHAEFER W. RIEGEL E. STEPHAN H. KELLER W. H. H
RL A. HEIDLAND 《European journal of clinical investigation》1990,20(1):35-40
Hepatic amino acid uptake, urea and glucose production are increased in acute uraemia. It has been shown that this metabolic pattern is mediated by glucocorticoids. Accordingly, the administration of the antiglucocorticoid RU 38486 to acutely uraemic rats resulted in a reduction of serum urea-N and glucose levels. To clarify whether this effect is due to a reduction in hepatic gluconeogenesis we examined the effect of the antiglucocorticoid RU 38486 on urea and glucose formation in isolated hepatocytes from sham-operated (SHAM) and bilaterally nephrectomized (BNX) rats receiving RU 38486 or the vehicle only. Hepatic glucose production in BNX rats was considerably increased from Na-pyruvate (+79%), alanine (+174%), glutamine (+158%), and serine (+87%) compared with SHAM animals. Concomitantly, hepatic urea formation was also enhanced from amino acid substrates in acutely uraemic rats. When uraemic animals were treated with RU 38486, glucose production from amino acids and Na-pyruvate was reduced to the range of SHAM animals or even lower. This effect could not be demonstrated in SHAM-operated controls. A comparable decrement in hepatic urea production was observed in BNX rats treated with the antiglucocorticoid. Thus, glucocorticoids appear to play a key role in the abnormal hepatic urea and glucose production of acutely uraemic rats. 相似文献