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991.
To determine safety and efficacy of tumor necrosis factor (TNF) and interferon-gamma (IFN gamma) in the treatment of patients with acquired immunodeficiency syndrome (AIDS)-related complex, a randomized, double-blind study was conducted. Twenty-five patients with AIDS-related complex and CD4 lymphocytes less than or equal to 500 x 10(6)/L attended an AIDS Clinical Trials Unit of a tertiary referral center. Patients were administered tumor necrosis factor (TNF) (10 micrograms/m2) or IFN gamma (10 micrograms/m2), or both intramuscularly three times weekly for 16 weeks. Side effects from all three preparations included fever, constitutional symptoms, and local reactions. No significant hematologic, hepatic, renal, or coagulation abnormalities were observed. CD4 lymphocyte counts, beta 2-microglobulin, p24 antigen levels, and anti-p24 antibody did not change significantly during therapy. Similarly, no significant change was noted in rates of HIV isolation from peripheral blood mononuclear cells or plasma. TNF and IFN gamma were tolerable after premedication with acetaminophen; however, no significant change in markers of human immunodeficiency virus infection was demonstrated. These cytokines alone do not appear to be of benefit, nor do they appear to hasten the progression of HIV infection.  相似文献   
992.
Intravascular stenting: from basic research to clinical application   总被引:4,自引:0,他引:4  
Although the use of intravascular stents is approaching widespread clinical use, several questions remain regarding their safety and efficacy. Several factors have direct bearing on the immediate and long-term results of intravascular stenting. The technical results of stenting are dependent on the mechanical characteristics of the device and long-term patency is closely related to thrombogenicity and endothelialization. Although stents are used most frequently for the treatment of atherosclerotic disease there is no clear understanding of how they influence the atheromatous lesion.  相似文献   
993.
OBJECTIVE: To study the effect of a moderate, aerobic physical exercise program on insulin resistance and its accompanying metabolic changes in a group of healthy, middle-age, nonobese subjects, without modifying oxygen consumption and body weight. DESIGN: The inclusion of subjects was carried out among volunteers from the health personnel of our center, who complied with the inclusion criteria. PARTICIPANTS: Twelve subjects (age 30-60 years, 5 females), nonsmokers, body mass index (BMI) <27 kg/m2 and fasting plasma glucose <6.1 mmol/L. INTERVENTIONS: Insulin resistance was assessed using the Bergmann minimal model modified with insulin, and basal and maximum metabolic rate were measured with standard methods. All subjects completed a 2-month program of aerobic exercise using the American College of Sports Medicine guidelines, consisting of aerobic exercise of moderate, regular, and continual intensity (3 times per week), with a duration of 45 to 50 minutes per session. RESULTS: Following controlled exercise, no significant differences in BMI, waist-hip ratio, blood pressure, lipids, free fatty acids, and leptin plasma values were observed. Plasma glucose and insulin values decreased significantly (-0.37 mmol/L and -16.5 pmol/L, respectively). Insulin sensitivity showed an increase of 2.1 x 10(-4) mU L(-1) min(-1) (P = 0.001). Basal and maximum metabolic rate showed no significant differences after the exercise program. CONCLUSIONS: Moderate aerobic exercise increases insulin sensitivity in nonobese, nondiabetic subjects in the absence of significant changes in weight, BMI, waist-hip ratio, lipid profile, and oxygen consumption.  相似文献   
994.
一国的疾病负担情况、医疗体制、政府是否具有在青少年中启动接种HPV疫苗计划的能力以及公众的接受度等因素,是该疫苗进入任何一个国家所面临的问题。而在发展中国家,对此疫苗的普及尤为迫切。  相似文献   
995.
Approximately 5 percent of patients with systemic lupus erythematosus by clinical and pathologic criteria have no demonstrable antinuclear antibodies. This figure is likely to be an underestimate, as it does not include the antinuclear antibody-negative patients with limited manifestations in whom the diagnosis of systemic lupus erythematosus is missed. A 23-year-old woman is described who had a history of perplexing bilateral pleural effusions with development of peritoneal effusion after 18 months and positive antinuclear antibody results after 22 months. Tissue pathologic features, initially interpreted as nonspecific, on review revealed striking lymphocytic periarteritis with endothelial swelling and leukocytoclastic vasculitis often seen in systemic lupus. A selective defect in the suppression of T cell effector function, such as direct cell-mediated cytotoxicity, with intact suppressor systems for B cell effector function, such as antibody production, can be postulated in this patient. This would explain the active cellular tissue pathology with the lack of prominent antinuclear antibody production.  相似文献   
996.
997.
This prospective clinical study assessed the effect of the Fr?nkel Functional Regulator-II (FR-II) treatment on the position and shape of the articular disc of the temporomandibular joint. The sample included magnetic resonance images of 112 temporomandibular joints taken initially (T1) and after 18 +/- 1 months (T2). The subjects were 56 white Brazilian children who were beginning their pubertal growth spurt. They had Class II Division 1 malocclusions and were selected from 800 children in neighborhood schools. They were randomly dichotomized into either the treated group (treated with the FR-II for 18 months) or the control group (not treated during the observation period). Our findings showed a low prevalence (3.57%) of disc displacement in the 112 temporomandibular joints. Mandibular propulsion with the FR-II had no unfavorable effect on the temporomandibular joints of the treated group; 100% of the patients kept an upper and interposed disc position (closed and open mouth, respectively) at T1 and T2. The control group had 7.1% partial anterior medial disc displacement, both at T1 and T2. Regarding disc morphology, the control group showed biconcave-shaped discs in 82.1% of the joints, statistically similar to the treated group (89.3%) at the beginning of the observation period. At T2, the articular disc morphology of the control group was unchanged, but that of the treated group was significantly more normal (P =.016), progressing from nonbiconcave at T1 (10.7%) to biconcave at T2 (100%). Our results showed that disc displacement is not a complication of functional appliance therapy; in fact, such treatment might help some children with incipient temporomandibular disorders.  相似文献   
998.
999.
1000.
Free radical copolymerization of a macromer and a vinylic or acrylic monomer is a novel method of synthesis of graft copolymers. Each macromer unit gives yield to a graft. Accurate characterization of the samples obtained, especially by means of proton NMR, is possible. The distribution of the grafts along the chain is random. The overall molecular weights of the copolymers formed are low, however.  相似文献   
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