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51.
Context  Anemia is common in critically ill patients and results in a large number of red blood cell (RBC) transfusions. Recent data have raised the concern that RBC transfusions may be associated with worse clinical outcomes in some patients. Objective  To assess the efficacy in critically ill patients of a weekly dosing schedule of recombinant human erythropoietin (rHuEPO) to decrease the occurrence of RBC transfusion. Design  A prospective, randomized, double-blind, placebo-controlled, multicenter trial conducted between December 1998 and June 2001. Setting  A medical, surgical, or a medical/surgical intensive care unit (ICU) in each of 65 participating institutions in the United States. Patients  A total of 1302 patients who had been in the ICU for 2 days and were expected to be in the ICU at least 2 more days and who met eligibility criteria were enrolled in the study; 650 patients were randomized to rHuEPO and 652 to placebo. Intervention  Study drug (40 000 units of rHuEPO) or placebo was administered by subcutaneous injection on ICU day 3 and continued weekly for patients who remained in the hospital, for a total of 3 doses. Patients in the ICU on study day 21 received a fourth dose. Main Outcome Measures  The primary efficacy end point was transfusion independence, assessed by comparing the percentage of patients in each treatment group who received any RBC transfusion between study days 1 and 28. Secondary efficacy end points identified prospectively included cumulative RBC units transfused per patient through study day 28; cumulative mortality through study day 28; change in hemoglobin from baseline; and time to first transfusion or death. Results  Patients receiving rHuEPO were less likely to undergo transfusion (60.4% placebo vs 50.5% rHuEPO; P<.001; odds ratio, 0.67; 95% confidence interval [CI], 0.54-0.83). There was a 19% reduction in the total units of RBCs transfused in the rHuEPO group (1963 units for placebo vs 1590 units for rHuEPO) and reduction in RBC units transfused per day alive (ratio of transfusion rates, 0.81; 95% CI, 0.79-0.83; P = .04). Increase in hemoglobin from baseline to study end was greater in the rHuEPO group (mean [SD], 1.32 [2] g/dL vs 0.94 [1.9] g/dL; P<.001). Mortality (14% for rHuEPO and 15% for placebo) and adverse clinical events were not significantly different. Conclusions  In critically ill patients, weekly administration of 40 000 units of rHuEPO reduces allogeneic RBC transfusion and increases hemoglobin. Further study is needed to determine whether this reduction in RBC transfusion results in improved clinical outcomes.   相似文献   
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PURPOSE: Mini percutaneous nephrostolithotomy was developed for use in children and in adults with a reduced renal reserve to minimize the morbidity and renal parenchymal damage presumed to occur with traditional percutaneous nephrostolithotomy. We compared the extent of renal injury incurred by different sized nephrostomy tracts in female farm pigs undergoing 11 or 30Fr percutaneous nephrostomy. MATERIALS AND METHODS: Bilateral percutaneous nephrostomy was attempted via a mid or lower pole calix under fluoroscopic guidance in 6 pigs. In 2 pigs the procedure was unsuccessful on 1 side, leaving 5 successfully established nephrostomy tracts on each side. In each pig the right percutaneous tract was dilated with a 28Fr dilating balloon and a 30Fr Amplatz working sheath (Cook Urological, Spencer, Indiana) was positioned in the collecting system. On the left side an 11Fr sheath (Cook Urological) was placed. The sheaths were removed after 1 hour and nephrostomy tubes (22Fr on the right and 8Fr on the left side) were left in place overnight and then removed. Six weeks later the pigs were sacrificed and the kidneys were harvested. The nephrostomy tracts were identified grossly and examined microscopically, and the fibrotic scar was measured using digital analysis. The volume of scar was estimated using the calculated volume of a cylinder. RESULTS: At kidney harvest all 10 kidneys appeared grossly normal. No intra-abdominal urine collection or perirenal hematoma was noted. Mean estimated scar volume of the 30 and 11Fr tracts was 0.29 and 0.40 cc, which translates into a mean fractional loss of parenchyma of 0.63% and 0.91%, respectively (p not significant). CONCLUSIONS: Renal parenchymal damage resulting from the creation of a nephrostomy tract is small compared to overall renal volume regardless of the size of the nephrostomy tract. Consequently there is no advantage to the use of a small access sheath based on renal scarring alone.  相似文献   
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Neonatal screening for phenylketonuria (PKU) has created a problem as females with PKU are reaching child-bearing age. Surveys have revealed that maternal phenylalanine blood concentrations greater than 1200 μmol/l are associated with fetal microcephaly, congenital heart defects and intrauterine growth retardation. It is estimated that as many as 3000 hyperphenylalaninemic females may be at risk of producing these fetal abnormalities. To examine this problem, the international maternal PKU collaborative study was developed to evaluate the efficacy of a phenylalanine-restricted diet in reducing fetal morbidity. Preliminary findings have indicated that phenylalanine restriction should begin before conception for females with PKU planning a pregnancy. Dietary control should maintain maternal blood phenylalanine levels between 120 and 360 μmol/l and should provide adequate energy, protein, vitamin and mineral intake. Pregnant hyperphenylalaninemic females who achieved metabolic control after conception or by the 10th week of pregnancy had a better offspring outcome than anticipated. The results of 402 pregnancies are reviewed.  相似文献   
56.
Controversies in transfusion medicine. Perioperative hemodilution: pro   总被引:4,自引:0,他引:4  
Hemodilution can obviate the need for allogeneic transfusion in some patients. However, it is only one component of a comprehensive blood conservation program and should be combined with other techniques whenever possible. While most often employed in teenagers and healthy young adults, ANH has been used in small children, the elderly, and patients of all ages who are undergoing cardiac surgery. Extreme caution should be exercised if ANH is used in patients with coronary artery disease or aortic stenosis who are undergoing noncardiac surgery, because their normal compensatory mechanisms are impaired. What usually is a safe and relatively simple procedure can become a disaster if employed in inappropriately selected patients. Careful hemodynamic monitoring and maintenance of normovolemia are critical.  相似文献   
57.
Clinical decision analysis and a computer model were used to evaluate the performance of alternative strategies for the diagnosis of neoplasia in adults with asymptomatic microscopic hematuria. Strategies consisted of sequences of diagnostic tests, including ultrasound, excretory urography, angiography, computerized tomography and cystoscopy. The strategies have a sensitivity of 98 to 100 per cent for bladder cancer and 90 to 94 per cent for renal carcinoma, and a specificity of 99 per cent. The cost per carcinoma diagnosed is $75,000 to $86,000 at 1 per cent prevalence and $5,000 to $5,800 at 15 per cent prevalence. Strategies using cystoscopy or ultrasound as the initial diagnostic test minimized cost and morbidity while maintaining diagnostic accuracy. Excretory urography does not add significantly to diagnostic accuracy but it does add to cost and morbidity.  相似文献   
58.
引用违法传递概念设计合成了11个C-末端含氧代赖氨酸二肽,进行抗深部致病菌-白念珠菌活性试验,体外实验结果显示极强的抑菌活性,MIC在12.5~0.8μg/disk之间,较母体氧化赖氨酸大50~135倍(克分子比。  相似文献   
59.
ABSTRACT. We examined whether the abnormal regulation of the cardiovascular system and plasma noradrenaline observed after oral glucose in insulin-dependent diabetic patients could be normalized by intravenous infusion of insulin. Eight patients with type 1 (insulin-dependent) diabetes were examined after an oral glucose load with and without simultaneous infusion of insulin. Insulin infusion increased plasma insulin from 0.07 to 0.31 nmol/1. In the control experiment (glucose only), mean heart rate and mean arterial systolic blood pressure remained unchanged and plasma noradrenaline (NA) decreased (p < 0.05). After oral glucose plus intravenous insulin, mean heart rate increased by 11 % and mean systolic blood pressure by 5 % (p < 0.05, p < 0.01), whereas plasma NA did not change significantly. The present study indicates that physiologic increments in plasma insulin concentration are of importance in the regulation of the cardiovascular system and plasma NA following an oral glucose load.  相似文献   
60.
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