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Turndowns of offers of deceased donor kidneys for transplantation can contribute to inefficiencies in the organ distribution system and inequality in access to donated organs. Match run data were obtained for 4967 'good' kidneys placed and transplanted in 2005 after fewer than 50 offers. These kidneys were not recovered from donation after cardiac death or expanded criteria donors, or from donors with a history of substance abuse. On average, these good kidneys were not accepted until after seven offers to candidates and after offers to 2.4 programs. Models for the likelihood of acceptance found several donor and candidate characteristics to be significantly related to acceptance rates (p < 0.05). After accounting for these variables, there remained 2- to 3-fold differences among transplant programs in acceptance rates. These models could be used to identify kidney transplant centers with exceptional acceptance practices. Several strategies might be employed to increase acceptance rates for good organs.  相似文献   
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We have investigated the role of basal insulin concentration on leucine kinetics (determined by means of 1-[13C]leucine) and energy metabolism (determined by indirect calorimetry) in eight septic patients by reducing insulin (and glucagon) secretion by somatostatin infusion. Basal glucagon concentration was elevated (744 +/- 381 pg/mL), and insulin concentration was normal (10 +/- 4 microU/mL). Basal resting energy expenditure (REE) was 151 +/- 8% that of predicted basal energy expenditure, and leucine appearance (Ra), oxidation, and nonoxidative disposal rates were all elevated above the normal ranges. Somatostatin infusion reduced insulin concentration by 52% and glucagon concentration by 64%. This resulted in a significant increase in the rate of leucine oxidation from 0.96 +/- 0.08 to 1.18 +/- 0.14 mumol/kg/min (p less than 0.01), and nonoxidative leucine disposal decreased from 2.95 +/- 0.18 to 2.67 +/- 0.17 mumol/kg/min (p less than 0.01). Somatostatin infusion also caused significant increases in REE and fat oxidation from 1310 +/- 100 to 1505 +/- 128 kcal/m2/day (p less than 0.05) and from 1.72 +/- 0.24 to 2.41 +/- 0.41 mg/kg/min, respectively, and a slight decrease of carbohydrate oxidation from 1.51 +/- 0.49 to 1.31 +/- 0.49 mg/kg/min. These metabolic responses can be attributed to the reduction in insulin concentration, because they are in the opposite direction of changes that would occur as a consequence of a reduction in glucagon concentration. We conclude that the basal insulin plays an important role in attenuating net protein loss and energy expenditure.  相似文献   
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We describe the presence of cylindrical spirals on muscle biopsy from a 31-year-old man who developed rhabodomyolysis following a long run. He had a prior history of exertional cramps and myoglobinuria. His maternal grandfather had similar symptoms. Transmission electron micrographs demonstrated continuity between the lamellae of the cylindrical spirals and native myofilaments. Whether these unusual structures confer a derangement in myofilament function is uncertain.  相似文献   
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Both cyproterone acetate (CPA) and the gonadotrophin-releasing hormone agonist (GnRHa) have been shown to be effective for the treatment of hirsutism. We wished to compare the effectiveness of CPA in two standard doses with GnRHa and add-back therapy and to compare the length of remission after these treatments. A total of 60 hirsute hyperandrogenic women was assigned to the following treatment groups: CPA 2 mg with 35 microg of ethinylestradiol for 21 days each month (Diane group), CPA 50 mg, days 5-15, and ethinylestradiol 50 microg, days 5-25, each month (CPA group) or Decapeptyl 3.75 mg i.m. every 28 days with the addition of conjugated oestrogen 0.625 mg, days 1-21, and medroxyprogesterone acetate 10 mg, days 12-21 (GnRHa group). Hirsutism was graded by the Ferriman-Gallwey-Lorenzo (FGL) index and anagen hair shaft diameters and serum luteinizing hormone (LH) and testosterone were assessed before and every 3 months during and after treatment. All women were treated for 1 year with 1 year follow-up. At baseline hirsutism and endocrine patterns were similar in all groups. After one year of treatment, hirsutism decreased in all groups but the changes were greater (P <0.05) in the CPA and GnRHa groups than in the Diane group. Serum LH and testosterone were lowest in the GnRHa group. After withdrawal, hirsutism increased rapidly in the Diane and CPA groups and after 6 months, FGL scores and hair shaft diameters were similar to pretreatment values. In the GnRHa group, hirsutism increased more gradually and after 1 year of withdrawal, FGL scores and hair diameters were significantly (P <0.05) less than pretreatment values. Serum LH and testosterone increased rapidly in all three groups reaching pretreatment values by 6 months. These data suggest equal efficacy of the GnRHa and the high dose CPA regimen for the treatment of hirsutism in hyperandrogenic women. GnRHa with add-back treatment appears to result in a longer remission of hirsutism in comparison with CPA.   相似文献   
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BACKGROUND: In general practice, acute sinusitis is frequently diagnosed and treated with antibiotics. OBJECTIVE: This study aimed to determine the evidence for the effectiveness of antibiotic treatment in acute maxillary sinusitis in adults by assessing the methodological quality of placebo-controlled double-blind randomized trials. METHOD: An evaluation by four raters through a 35-item scoring-scale for internal and external validity of all placebo-controlled double-blind randomized trials on acute sinusitis found between January 1966 and July 1996. RESULTS: Eighty-five trials were excluded because they were not placebo-controlled, double-blind, randomized, or were carried out in patients with chronic sinusitis or in children. The three remaining trials were performed in different populations (one in general practice) between 1973 and 1978. Only one study claimed superiority of antibiotic treatment. Different inclusion criteria and major outcome measures were used by the authors. The reliability of major outcome events was reported poorly or not at all and in two studies outcome measures were clinically inappropriate. The studies scored 30-62% of the maximum attainable score for internal validity and 10-20% for external validity. CONCLUSION: The effectiveness of antibiotic treatment in acute maxillary sinusitis in a general practice population is not based sufficiently on evidence.   相似文献   
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