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81.
PURPOSE: We designed and conducted a randomized single-institution trial comparing two common prophylactic platelet transfusion thresholds in patients undergoing induction therapy for acute leukemia. PATIENTS AND METHODS: Seventy-eight patients undergoing induction therapy for acute leukemia were randomized to receive prophylactic apheresis platelet concentrates when the platelet count was either < or = 10,000/microL or < or = 20,000/microL. RESULTS: There was no significant difference in the total number of bleeding episodes per patient with a median of four in the < or = 10,000/microL arm and two in the < or = 20,000/microL arm (25th to 75th percentiles of 2, 7 and 1, 5, respectively; P = .12). Patients randomized to the < or = 10,000/microL arm received more platelet transfusions for bleeding [one (0, 2) v zero (0, 0); P = .0003]. In contrast, patients on the < or = 20,000/microL arm received more platelet transfusions for prophylactic indications [10 (5, 14) v six (3, 8); P = 0.001], as would be expected, but less for bleeding. Nevertheless, the total number of platelet transfusions given to patients on the < or = 20,000/microL arm was higher and nearly significant [11 (6, 15) v seven (5, 11); P = .07]. There were no statistically significant differences between the groups with regard to RBC transfusion requirements, febrile days, days hospitalized, days thrombocytopenic, need for HLA-matched platelets, remission rate, or death during induction chemotherapy. No patient in either group died from hemorrhage or underwent major surgery for bleeding complications. CONCLUSION: Giving prophylactic platelets at a threshold of < or = 10,000/microL compared with < or = 20,000/microL can decrease the total utilization of platelets with only a small adverse effect on bleeding, and no statistically significant effect on morbidity.  相似文献   
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This study examines the influence of six patient characteristics (age, race, socioeconomic status, comorbidities, mobility and presentational style) and two physician characteristics (medical specialty and years of clinical experience) on physicians' clinical decision making behaviour in the evaluation treatment of an unknown and known breast cancer. Physicians' variability and certainty associated with diagnostic and treatment behaviour were also examined. Separate analyses explored the influence of these non-medical factors on physicians' cognitive processes. Using a fractional factorial design, 128 practising physicians were shown two videotaped scenarios and asked about possible diagnoses and medical recommendations. Results showed that physicians displayed considerable variability in response to several patient-based factors. Physician characteristics also emerged as important predictors of clinical behaviour, thus confirming the complexity of the medical decision-making process.  相似文献   
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OBJECTIVE: To characterize Seprafilm bioresorbable membrane and assess its efficacy and safety in reducing adhesions. DESIGN: In vitro and animal studies designed to provide precise control of tissue trauma and closely approximate clinically relevant conditions in abdominal surgery. SETTING: Experimental laboratories, USA. SUBJECTS: Experimental animals, principally rats and rabbits. INTERVENTIONS: The rat cecal abrasion or sidewall injury model evaluated the efficacy of seprafilm in the presence of blood and irrigation solutions, in multiple layers, under ischemic conditions, and in adhesion reformation. A rabbit anastomosis model tested the effect of the membrane on wound healing, and a series of challenge tests determined its toxicology, immunogenicity, and biocompatibility. MAIN OUTCOME MEASURES: Incidence and severity of adhesions; mutagenicity; pyrogenicity; irritation effects; systemic toxicity. RESULTS: Seprafilm significantly reduced the number of cecal adhesions (p < 0.001) and the number of animals with severe adhesions (p < 0.001) when compared with nontreated controls, even in the presence of bleeding. The membrane also significantly decreased the number of animals with any adhesions (p < 0.001). Seprafilm maintains efficacy when used with excess irrigation solutions, when layered, and under ischemic conditions. Among rats tested for adhesion reformation, the treated group had a significantly larger proportion of adhesion-free animals than the untreated group, 72% versus 28%, (p = 0.007). Seprafilm did not impair wound healing in anastomosis and is nontoxic, nonmutagenic, nonimmunogenic, nonpyrogenic, nonirritating, and biocompatible. CONCLUSION: Preclinical studies have shown that Seprafilm is safe and effective in reducing postsurgical adhesions. Seprafilm meets the requirements of an ideal barrier and can be a useful adjuvant in abdominal and pelvic surgery.  相似文献   
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Non-synchronous rotation of Europa was predicted on theoretical grounds, by considering the orbitally averaged torque exerted by Jupiter on the satellite's tidal bulges. If Europa's orbit were circular, or the satellite were comprised of a frictionless fluid without tidal dissipation, this torque would average to zero. However, Europa has a small forced eccentricity e approximately 0.01 , generated by its dynamical interaction with Io and Ganymede, which should cause the equilibrium spin rate of the satellite to be slightly faster than synchronous. Recent gravity data suggest that there may be a permanent asymmetry in Europa's interior mass distribution which is large enough to offset the tidal torque; hence, if non-synchronous rotation is observed, the surface is probably decoupled from the interior by a subsurface layer of liquid or ductile ice. Non-synchronous rotation was invoked to explain Europa's global system of lineaments and an equatorial region of rifting seen in Voyager images. Here we report an analysis of the orientation and distribution of these surface features, based on initial observations made by the Galileo spacecraft. We find evidence that Europa spins faster than the synchronous rate (or did so in the past), consistent with the possibility of a global subsurface ocean.  相似文献   
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Leukodystrophies are progressive disorders involving the development and maintenance of myelin in the central and peripheral nervous systems. Although relatively uncommon, leukodystrophic disorders may be undiagnosed or misdiagnosed during life, and may appear as "sudden death." In such instances, these victims may be referred to a forensic pathologist. In general, leukodystrophies are inherited in an autosomal recessive manner so that proper postmortem diagnosis by the forensic pathologist is extremely important to the decendant's family for future family planning.  相似文献   
89.
Competition has been studied as something to be averted, yet rarely has it been asked what processes may be involved in successful competition. The authors tested whether more accurate modeling of an adversary can assist competitive success. Pairs played a zero-sum game with no specific skill component over 40 trials. The authors measured the relative accuracy of the players' second-order model (i.e., what I think about my opponent: R2MA) and third-order model (i.e., what I think my opponent thinks of me: R3MA), using responses to adjectives indicating personality traits. Performance correlated with both R3MA and having a better strategy (i.e., a better distribution of responses), but these variables contributed separately to performance variance. However, R2MA did not correlate with performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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