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排序方式: 共有1495条查询结果,搜索用时 71 毫秒
161.
T Gayowski N Singh IR Marino H Vargas M Wagener C Wannstedt F Morelli T Laskus JJ Fung J Rakela TE Starzl 《Canadian Metallurgical Quarterly》1997,64(3):422-426
BACKGROUND: End-stage liver disease due to hepatitis C virus (HCV) is the most common indication for liver transplantation in U.S. veterans. We investigated the influence of HCV genotypes on the incidence and timing of recurrent HCV hepatitis, survival, infectious morbidity, and response to interferon-alpha therapy in this unique patient population. METHODS: HCV genotype was determined by direct sequencing of the NS5 region of HCV with type-specific primers. RESULTS: Genotype 1a (66%, 32/47) was the predominant genotype. Type 1b was found in 25% (12/47) of patients and type 2b was found in 9% (4/47). Histopathologically recurrent HCV hepatitis developed in 53% (25/47) of the patients after transplantation. This group included 45% (14/31) of the patients with type 1a, 67% (8/12) of the patients with type 1b, and 25% (1/4) of the patients with type 2b (P>0.5). The time to recurrence and the severity of HCV recurrence as defined by aminotransferase levels or Knodell scores were not different among the three genotypes. There was a trend toward a higher incidence of major infections in patients with type 1b (75%) versus type 1a (48%) and type 2b (50%) (P=0.11). The response to interferon-a therapy did not differ significantly among the genotypes. Mortality at 5 years was 16% (5/31) in patients with genotype 1a, 42% (5/12) in patients with genotype 1b, and 50% (2/4) in patients with genotype 2b (P=0.06). CONCLUSIONS: The incidence, time to recurrence, and response to interferon-alpha therapy did not differ between the various genotypes in our liver transplant recipients. However, there was a trend toward higher infectious morbidity and overall mortality in patients with genotype 1b after transplantation. 相似文献
162.
Rate Monotonic vs. EDF: Judgment Day 总被引:13,自引:2,他引:11
Since the first results published in 1973 by Liu and Layland on the Rate Monotonic (RM) and Earliest Deadline First (EDF) algorithms, a lot of progress has been made in the schedulability analysis of periodic task sets. Unfortunately, many misconceptions still exist about the properties of these two scheduling methods, which usually tend to favor RM more than EDF. Typical wrong statements often heard in technical conferences and even in research papers claim that RM is easier to analyze than EDF, it introduces less runtime overhead, it is more predictable in overload conditions, and causes less jitter in task execution.Since the above statements are either wrong, or not precise, it is time to clarify these issues in a systematic fashion, because the use of EDF allows a better exploitation of the available resources and significantly improves system's performance.This paper compares RM against EDF under several aspects, using existing theoretical results, specific simulation experiments, or simple counterexamples to show that many common beliefs are either false or only restricted to specific situations. 相似文献
163.
164.
G Lelli A Tartarone C D'Addetta M D'Aloia G Di Maggio F Morelli 《Canadian Metallurgical Quarterly》1998,149(921):21-24
PURPOSE: To verify tolerance and clinical efficacy of high-dose chemotherapy (HDCT) in metastatic breast cancer (MBC). PATIENTS AND METHODS: We submitted to HDCT with autologous peripheral blood cells transplant 66 patients, with MBC responding to induction chemotherapy. The condizioning regimen was ICE: iphosphamide 3.3 g/m2 dd. -8/-6, carboplatin 450 mg/m2 plus etoposide 400 mg/m2 dd. -5/-3 (21 patients = 78%); CTM: cyclophosphamide 100 mg/kg dd. -4/-3, tyothepa 500 mg:m2 d.-5, mytoxantrone 40 mg/m2 d. -6 (6 patients, 22%). RESULTS: Median number of aphereses was 2 (range 1-5), median amount of CD34+ cells/kg bw of 10 x 10E6 (range 3.5-38.2). Median recovery time was 10th day for PMN (range 8-37) while for platelets it was 9th day (range 8-37): total hospital stay was of 24 days (range 22-48). After induction therapy we had PR in 13/27 metastatic patients (48%) and CR in 14/27 (52%). After conditioning treatment we had PR in 12/27 (44%) and CR in 15/27 (56%). Median time to progression was 19 months (range 7-38) and median survival 52 months (range 7-59+), with 30% surviving beyond 4 years. CONCLUSIONS: Feasibility of HDCT in advanced breast cancer seems verified. The promising results need to be confirmed. 相似文献
165.
Rothbaum Fred; Weisz John; Pott Martha; Miyake Kazuo; Morelli Gilda 《Canadian Metallurgical Quarterly》2001,56(10):827
Replies to comments by 7 authors (see records 2001-18772-008, 2001-18772-009, 2001-18772-010, 2001-18772-011, and 2001-18772-012) in reference to the F. Rothbaum et al's original article (see record 2000-02781-001), which highlighted evidence of cultural variations in, and noted ways in which attachment theory is laden with Western values and meaning in comparisons of the US and Japan. Here, Rothbaum et al defend their central thesis and note areas of their agreement and disagreement with the aforementioned comments and criticisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
166.
Ignazio Renato Bellobono Bruno Marcandalli Elena Selli Alessandra Polissi Giorgio Leidi 《应用聚合物科学杂志》1984,29(10):3185-3195
A model has been applied to release of plasticizers from polymer films through vapor phase, for which the overall rate of release may be generally determined by evaporation of the plasticizer from the surface of the film, and/or by migration to the surface at below saturation in the polymer. The experimental system employed made use of n-butyl formate, diethyl-phthalate, di-n-butylphthalate, and N,n-butylbenzenesulfonamide as model molecules in polycaprolactam films, both with the aims of studying undesirable loss of plasticizers, and of simulating a model able to envisage releasing, at a constant rate, of any desired additive, with relatively high solubility and vapor pressure, to the content of packaging films. Experimental measurements were made (at 298–333 K) by investigating in a suitable cell the permeation of plasticizers both at concentrations below and above the saturation limit. Rate of evaporation of plasticizers from the membrane surface above the saturation limit, measured in this cell, were found to coincide satisfactorily with those calculated by application of the mass transfer theory to evaporation from a stationary liquid into a stirred gas, at a known velocity of gas flowing past the surface. From these latter rates and solubilities, the mass transfer coefficients H for evaporation could be obtained, as well as from experimental time lags the diffusivities Dp through the polymer membrane. In the light of the theoretical model a correlation was found between activation energies of H and evaporation enthalpies of the model molecules. 相似文献
167.
168.
The potentialities for 1-aryl-5-methyl-3-hydroxypyrazoles as intermediates in the field of dyes have been analysed. Some azoic derivatives have been synthesized and both electronic spectra and tinctorial properties on various substrates (wool, nylon, polyester, plasticized PVC) examined. The effect of substituents on the position of the long wavelength absorption maxima is discussed in terms of Hammett σ constants and interesting relationships are obtained. For each application the most important technical properties are assessed and significant fastness to various agents is evaluated.Finally a comparison with properties of similar pyrazol-5-one derivatives is made. 相似文献
169.
170.
Summary An investigation of the distribution of the cyclic oligomers of poly(lactic acid), formed both by pyrolysis of the polymer and by equilibration with a catalyst, has been performed by Negative Chemical Ionization and Thermospray Mass Spectrometry.The results indicate that the two methods can be used to obtain information on the relative amounts of the oligomers present in the mixture. 相似文献