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41.
A Seth I Ourmanov MJ Kuroda JE Schmitz MW Carroll LS Wyatt B Moss MA Forman VM Hirsch NL Letvin 《Canadian Metallurgical Quarterly》1998,95(17):10112-10116
The utility of modified vaccinia virus Ankara (MVA) as a vector for eliciting AIDS virus-specific cytotoxic T lymphocytes (CTL) was explored in the simian immunodeficiency virus (SIV)/rhesus monkey model. After two intramuscular immunizations with recombinant MVA-SIVSM gag pol, the monkeys developed a Gag epitope-specific CTL response readily detected in peripheral blood lymphocytes by using a functional killing assay. Moreover, those immunizations also elicited a population of CD8+ T lymphocytes in the peripheral blood that bound a specific major histocompatibility complex class I/peptide tetramer. These Gag epitope-specific CD8+ T lymphocytes also were demonstrated by using both functional and tetramer-binding assays in lymph nodes of the immunized monkeys. These observations suggest that MVA may prove a useful vector for an HIV-1 vaccine. They also suggest that tetramer staining may be a useful technology for monitoring CTL generation in vaccine trials in nonhuman primates and in humans. 相似文献
42.
PA Hollander SC Elbein IB Hirsch D Kelley J McGill T Taylor SR Weiss SE Crockett RA Kaplan J Comstock CP Lucas PA Lodewick W Canovatchel J Chung J Hauptman 《Canadian Metallurgical Quarterly》1998,21(8):1288-1294
OBJECTIVE: Obesity is an important risk factor for type 2 diabetes. Weight loss in patients with type 2 diabetes is associated with improved glycemic control and reduced cardiovascular disease risk factors, but weight loss is notably difficult to achieve and sustain with caloric restriction and exercise. The purpose of this study was to assess the impact of treatment with orlistat, a pancreatic lipase inhibitor, on weight loss, glycemic control, and serum lipid levels in obese patients with type 2 diabetes on sulfonylurea medications. RESEARCH DESIGN AND METHODS: In a multicenter 57-week randomized double-blind placebo-controlled study, 120 mg orlistat or placebo was administered orally three times a day with a mildly hypocaloric diet to 391 obese men and women with type 2 diabetes who were aged > 18 years, had a BMI of 28-40 kg/m2, and were clinically stable on oral sulfonylureas. Changes in body weight, glycemic control, lipid levels, and drug tolerability were measured. RESULTS: After 1 year of treatment, the orlistat group lost 6.2 +/- 0.45% (mean +/- SEM) of initial body weight vs. 4.3 +/- 0.49% in the placebo group (P < 0.001). Twice as many patients receiving orlistat (49 vs. 23%) lost > or = 5% of initial body weight (P < 0.001). Orlistat treatment plus diet compared with placebo plus diet was associated with significant improvement in glycemic control, as reflected in decreases in HbA1c (P < 0.001) and fasting plasma glucose (P < 0.001) and in dosage reductions of oral sulfonylurea medication (P < 0.01). Orlistat therapy also resulted in significantly greater improvements than placebo in several lipid parameters, namely, greater reductions in total cholesterol, (P < 0.001), LDL cholesterol (P < 0.001), triglycerides (P < 0.05), apolipoprotein B (P < 0.001), and the LDL-to-HDL cholesterol ratio (P < 0.001). Mild to moderate and transient gastrointestinal events were reported with orlistat therapy, although their association with study withdrawal was low. Fat-soluble vitamin levels generally remained within the reference range, and vitamin supplementation was required in only a few patients. CONCLUSIONS: Orlistat is an effective treatment modality in obese patients with type 2 diabetes with respect to clinically meaningful weight loss and maintenance of weight loss, improved glycemic control, and improved lipid profile. 相似文献
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Hamidou Tembine Eitan Altman Rachid El-Azouzi Yezekael Hayel 《Telecommunication Systems》2011,47(1-2):137-152
We study in this paper some evolutionary games where competition between individuals from a large population occurs through many local interactions between randomly selected individuals. We focus on games that have the property of possessing a single interior evolutionarily stable strategy (ESS). We study in particular the effect of the time delays on the convergence of evolutionary dynamics to the ESS in an evolutionary game in which each pure strategy is associated with its own delay. In particular, we study a multiple access game as well as a Hawk and Dove game. We study the properties of the ESS in these games and also the effect of time delays on the convergence of various bio-inspired evolutionary game dynamics to the ESS. 相似文献
46.
Eitan Greenshtein 《Sequential Analysis》2013,32(3-4):149-159
Let {Xi} be i.i.d.{Fθ}.We consider the testing problem H1θ<θ0 vs H2θ≥θ0, where sampling is done sequentially in batches with variable batch sizes.For some parametric families {Fθ}, and under natural cost struc-ture, we characterize the Bayes procedures. This characterization of Bayes procedures lead to a similar characterization of essentially complete class of procedures. 相似文献
47.
E.H. Hirsch 《Vacuum》2010,85(3):373-379
Experiments show that under suitable conditions the introduction of oxygen can raise the surface ionization current emitted by a heated tungsten wire by several orders of magnitude. The ions in this case are alkali ions originating from alkali silicates normally present as additives in tungsten. From the simultaneous observation, in a varying ambient atmosphere, of both the positive ion current produced by surface ionization and of the electron current due to thermionic emission, it is concluded that the large observed increase in positive ion current is not primarily a consequence of an increase in the work function of tungsten, but is mainly due to a reduction in the residence time of the ions on the ionizing surface. This appears to be caused by alkali ions being preferentially replaced as an adsorbate on tungsten by the impinging oxygen molecules. The observations suggest that the increased ion production does not occur on the outer wire surface, but at inter-phase boundaries within the wire. 相似文献
48.
Following consultation with the Council of Editors and with approval from the Publications and Communications Board of the American Psychological Association (APA), it was agreed that in recognition of the appearance of Volume 100 in 1986, Journal of Comparative Psychology (JCP) would publish a set of discussions about our topic. The discussions, contributed in response to the following letters, written last year, appear in this issue. These discussions illustrate the richness and variety of some of the perspectives on the field of comparative psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
49.
The authors present a Sudden Infant Death Syndrome prevention program. The study analyses the data of 92 children having participated in the complex prevention program, including polysomnography, between May 1997 and February 1998. The role of polysomnography and its use as a clinical method is described through the statistical analysis of the results of the study. 相似文献