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排序方式: 共有627条查询结果,搜索用时 15 毫秒
81.
82.
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
83.
G Vanham Z Toossi CS Hirsch RS Wallis SK Schwander EA Rich JJ Ellner 《Canadian Metallurgical Quarterly》1997,78(3-4):145-158
Protective immunity against Mycobacterium tuberculosis (MTB) in animal models is based on cell-mediated immunity (CMI), involving bi-directional interactions between T cells and cells of the monocyte/macrophage (MO/MA) lineage. Key factors include MO-derived interleukin (IL)-12 and tumor necrosis factor (TNF)-alpha as well as T cell derived IL-2 and interferon (IFN)-gamma. These cytokines appear particularly crucial in the induction of MA-mediated elimination of mycobacteria. Several lines of evidence indicate that similar mechanisms are operating in humans. During active pulmonary tuberculosis (PTB), signs of both immune depression and immune activation are concomitantly present. Decreased tuberculin skin test reactivity in vivo and deficient IFN-gamma production by MTB-stimulated mononuclear cells in vitro are observed. On the other hand, the serum levels of several cytokines, including TNF, and other inflammatory mediators are increased and circulating MO and T cell show phenotypic and functional evidence of in vivo activation. In this review, we will discuss the evidence for three models, which could explain this apparent paradox: 1. Stimulation of the T cell-suppressive function from MO/MA; 2. Intrinsic T cell refractoriness, possibly associated with tendency to apoptosis (programmed cell death), and 3. Compartmentalization and redistribution of immune responses to the site of disease. The opportunistic behavior of MTB during human immunodeficiency virus (HIV) infection can be explained by suppression of type-1 responses at the level of antigen-presenting cells, CD4 T cells and effector macrophages. The ominous prognostic significance of intercurrent PTB during HIV infection seems primarily due to prolonged activation of HIV replication in macrophages. Supportive immune therapy during PTB could aim at correcting the type-1 deficiency either by IFN-gamma inducers (e.g. IL-12, IL-18) or by neutralizing the suppressive cytokines transforming growth factor beta (TGF-beta) and IL-10. Alternatively, inflammatory over-activity could be reduced by neutralizing TNF. Finally, anti-apoptotic therapies (e.g. IL-15) might be considered. 相似文献
84.
85.
MA Nowak AL Lloyd GM Vasquez TA Wiltrout LM Wahl N Bischofberger J Williams A Kinter AS Fauci VM Hirsch JD Lifson 《Canadian Metallurgical Quarterly》1997,71(10):7518-7525
Mathematical modeling of viral replication dynamics, based on sequential measurements of levels of virion-associated RNA in plasma during antiretroviral treatment, has led to fundamental new insights into human immunodeficiency virus type 1 pathogenesis. We took advantage of the simian immunodeficiency virus (SIV)-infected macaque model to perform detailed measurements and mathematical modeling during primary infection and during treatment of established infection with the antiretroviral drug (R)-9-(2-phosphonylmethoxypropyl)adenine (PMPA). The calculated clearance half-life for productively infected cells during resolution of the peak viremia of primary infection was on the order of 1 day, with slightly shorter clearance half-lives calculated during PMPA treatment. Viral reproduction rates upon discontinuation of PMPA treatment after 2 weeks were approximately twofold greater than those obtained just prior to initiation of treatment in the same animals, likely reflecting accumulation of susceptible target cells during treatment. The basic reproductive ratio (R0) for the spread of SIV infection in vivo, which represents the number of productively infected cells derived from each productively infected cell at the beginning of infection, was also estimated. This parameter quantifies the extent to which antiviral therapy or vaccination must limit the initial spread of virus to prevent establishment of chronic disseminated infection. The results thus provide an important guide for efforts to develop vaccines against SIV and, by extension, human immunodeficiency virus. 相似文献
86.
Robert L. Hirsch 《Journal of Fusion Energy》2002,21(2):113-116
Assuming significant technical success in the ITER project by the year 2015, it is likely that governments will want to develop a more comprehensive plan for DT tokamak fusion power commercialization. To provide a glimpse into many of the related issues, we construct conversations between the director of the U.S. fusion program and three specialists key to commercial fusion success: an environment and safety regulator, an environmentalist, and an electric generation investor. The insights from these imagined conversations will hopefully be of value as tokamak fusion power proponents plan beyond ITER. 相似文献
87.
We investigated the expression pattern of the endothelin-A receptor and endothelin 1 genes, the mutations of which affect the development of the mesectodermal derivatives of the neural crest. We show here that endothelin 1 is expressed by the environment of the cephalic neural crest cells invading branchial arches. Later on, while the neural crest-derived tissues of the head continue to express endothelin-A receptor, endothelin 1 is no longer expressed in their environment. 相似文献
88.
BT Hirsch 《Canadian Metallurgical Quarterly》1997,(336):33-41
Economic theory and evidence indicate that workers, employers, and healthcare personnel respond to the incentives built into state workers' compensation systems. Although empirical studies cannot provide precise estimates of the quantitative effects resulting from specific policy changes, research is useful in evaluating the qualitative effects of alternative policies. Studies show that workers' compensation claims are higher the more generous the level of benefits, the shorter the waiting period, and the more readily available is information on benefits to workers. States that decrease real benefit levels and lengthen the period required before workers are compensated for lost earnings can constrain future growth in workers' compensation costs, while continuing to provide partial compensation for workers with the most serious injuries. The most difficult problem facing policymakers is to design and implement reforms that take into account what are often the incompatible incentives of workers, employers, and medical care providers. 相似文献
89.
AIDS, whether real or threatened, poses a radical challenge to the psychological, social, and practical adaptation of individuals at various stages of human immunodeficiency virus (HIV) disease. The challenge arises from multiple sources, including disease progression, social discrimination, bereavement, pressure for life-style change, and neurological impairment associated with HIV brain infection. The consequences of this challenge to people with HIV infection, AIDS-related complex, AIDS, and AIDS dementia complex are reviewed. The potential for both personal crisis and personal growth in response to this challenge is highlighted. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
90.
Among Drosophila melanogaster, divergently selected for geotaxis intermittently over 600 generations (28 years), about 80,000 animals have been analyzed behavior-genetically. Each major chromosome pair from two lines was isogenized on an unselected isogenic background. Measurement of their behavioral effects revealed the relative magnitudes II?>?III?>?X for the negatively geotactic (high) line and X?>?III?>?II for the positively geotactic (low) line. When reversing selection for the now phenotypically stable high and low lines and then repeatedly relaxing the reversals, a new genetic homeostasis in the low line was indicated by the return of the reversed-line average scores towards the low extreme; that is, the low line has attained a stable equilibrium for positive geotaxis, an uncharacteristic behavior and an effect not seen before 1979. This change suggests the recent evolution of a new coadaptation among genes. Although not as conclusive, a similar genetic interpretation is suggested for the high line. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献