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R. A. Wolfe F. B. LaPorte A. M. Rodgers E. C. Roys G. Fant A. B. Leichtman 《American journal of transplantation》2007,7(S1):1404-1411
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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X J Zhang K R Kunkel F Jahoor R R Wolfe 《JPEN. Journal of parenteral and enteral nutrition》1991,15(4):394-399
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
5.
Gil I Wolfe Dennis K Burns Daniel Krampitz Richard J Barohn 《Neuromuscular disorders : NMD》1997,7(8):536-538
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
6.
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
7.
Maxillary sinusitis in adults: an evaluation of placebo-controlled double-blind trials 总被引:1,自引:0,他引:1
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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