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The use of expanded criteria donors (ECD) has been proposed to help combat the discrepancy between organ availability and need. ECD kidneys are associated with delayed graft function (DGF) and worse long-term survival. The aim of this study is to evaluate the impact of pulsatile perfusion (PP) on DGF and graft survival in transplanted ECD kidneys. From January 2000 to December 2003, 4618 ECD kidney-alone transplants were reported to the United Network for Organ Sharing. PP was performed on 912 renal allografts. The prognostic factors of DGF were analyzed using multivariate logistic regression analysis. Risk factors for reduced allograft viability were greater in donors and recipients of PP kidneys. Three-year graft survival of ECD kidneys preserved with PP was similar to cold storage (CS) kidneys. The incidence of DGF in PP kidneys was significantly lower than CS kidneys (26% vs. 36%, p < 0.001). Despite having a greater number of risk factors for reduced graft viability, the ECD-PP kidneys had similar graft survival compared to ECD-CS kidneys. The use of PP, by decreasing the incidence of DGF, may possibly lead to lower overall costs and increased utilization of donor kidneys.  相似文献   
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A 48-year-old man presented with malignant hypertension and massive proteinuria. Renal angiography showed complete obstruction of the left renal artery and 99mTc-mercaptoacetylglycine (MAG3) renography showed a nonfunctioning left kidney. Percutaneous transluminal renal angioplasty of the left renal artery was unsuccessful; hence, the patient underwent left nephrectomy because of uncontrolled hypertension and proteinuria. Histological examination of a right kidney specimen revealed lesions of focal segmental glomerulosclerosis with benign nephrosclerosis. In contrast, histology of the left kidney showed typical ischemic kidney with hypertrophy of arteriolar smooth muscle cells. The patient responded favorably to the nephrectomy, as his blood pressure and urinary protein dramatically decreased with no antihypertensive medication. This case illustrates the heterogeneous effect of the renin-angiotensin system on either kidney in patients with renovascular hypertension due to unilateral renal artery stenosis.  相似文献   
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The variability of blood pressure measured by oscillometry and the validity of this technique were studied in premature infants. Thirty premature babies whose postnatal age was six days or more had their blood pressure measured 11 times over a twenty-minute period for three consecutive days. Movements were found to have a very substantial influence on results that could not be reliably compared with values obtained invasively. No consistent pattern of variations of oscillometric results obtained during the eleven measurements of use for recommending a specific measurement time was found. Diastolic blood pressure fell gradually over the three-day study period. The most reliable of the eleven daily values was the lowest value for which good correlations were found between the three study days; this lowest value was not influenced by neonatal or postnatal factors.  相似文献   
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HEp-2 cell-adherent Escherichia coli and the human immunodeficiency virus (HIV) itself have recently been incriminated as causes of chronic HIV-associated diarrhea. This study sought to determine the prevalence of these two agents among HIV-infected patients with diarrhea in an outpatient setting in the United States and to compare their prevalence to that of other commonly recognized enteropathogens known to be present in this population. HEp-2 cell-adherent E. coli was found in 20 of 83 (24.1%) patients with diarrhea. A diffuse pattern of adherence was the most common, found in 14 of 20 (70%) patients, followed by a localized adherence pattern (6 of 20; 30%). An intestinal secretory immune response against the p24 antigen of HIV was found in 9 of 34 (27.5%) patients with HIV-associated diarrhea. The following pathogens or products were also detected in lower frequencies: Cryptosporidium spp. (10.8%), Clostridium difficile toxin (8.8%), microsporidia (6%), Isospora belli (3.6%), Blastocystis hominis (2.4%), Giardia spp. (1.2%), Salmonella spp. (1.2%), and Mycobacterium spp. (1.2%). The role of HEp-2 cell-adherent E. coli and HIV enteric infections in patients with HIV-associated diarrhea deserves further study.  相似文献   
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Data relating to stroke patients at a department of internal medicine (50 beds) in a county teaching hospital were studied in period 1990-1994. In this five-year period, 1184 patients were admitted because of some forms of stroke. The mortality due to the stroke was 16.8% (199 patients, deceased group). Autopsy was performed on 159 of these 199 patients (autopsy rate: 79.8%). Age- and sex-matched controls were selected from the survivors (n = 159). The main risk factors of stroke were analyzed in both groups: hypertension, cardiac events (decompensation, atrial fibrillation, and old myocardial infarction), previously verified diabetes, and recurrent stroke in the history. The mean hospital nursing time for the survivors was 12.3 +/- 6.3 days, while that in the deceased 7.2 +/- 7.6 days. RESULTS: 1. Hypertension was present to similar extents in both groups (survivors: 82.1%, deceased group: 77.8%) 2. Decompensation occurred in 5% vs 18.2% fibrillation in 11.3% vs 13.8%, and old myocardial infarction in 5.6% vs 18.2% 3. Diabetes was observed in 21.3% vs 36.4% and 4. Recurrent stroke in 22.6% vs 39.6%. These risk factors strongly predicted the outcome of the stroke. Other recently observed factors (haemorrhagic form, conscious state, time of hospital admission, seasonal variation, higher erythrocyte sedimentation rate, hyperglycaemia, proteinuria, early deep vein trombosis) revealed also significant differences between survivors and deceased patients. Since pulmonary thromboembolism was twice as frequent in the deceased patients as in the survivors, early heparin prevention is necessary immediately after computer tomography which excluded the haemorrhagic type of cerebrovascular diseases.  相似文献   
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