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11.
The impact of adolescent smoking cessation clinics has been disappointing due to low participation rates, high attrition, and low quit rates. This paper describes two computerized self-help adolescent smoking cessation intervention programs: 1) a program utilizing the expert system which is based on the transtheoretical model of change and 2) a popular action-oriented smoking cessation clinic program for teens which was modified for computer presentation. High participation rates in the program among 132 smokers demonstrate the high feasibility and acceptability of the programs. Quit rates of up to 20% were observed during the intervention, and an additional 30% made unsuccessful quit attempt(s). The 6-month follow-up findings indicated that adolescents were poorly prepared to maintain abstinence.  相似文献   
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针对实验室内难以构造的高海情PM谱海面,采用电磁缩比测量的方法研究其电磁散射特性,首先定量分析了以淡水替代海水造成不满足物理相似性要求而引入的误差,然后讨论了缩比PM谱海面满足几何相似性条件的要求,和对粗糙海面进行缩比模拟测量的途径,根据粗糙海面缩比模拟理论与条件,在实验室内成功模拟构造满足缩比测量理论的粗糙海面。  相似文献   
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Conditions predisposing to metabolic syndrome (MetS) are associated with increased oxidative stress and inflammation. We studied, in vegetarians (n = 90) and omnivores (n = 46), the impact of the dietary regimen on the occurrence of MetS risk factors (RFs: BMI, blood pressure, glucose metabolism and lipid profile) in relation to oxidative status (advanced glycation end products (AGEs), advanced oxidation protein products (AOPPs), malondialdehyde, ferric reducing ability of plasma, vitamins A, E, C, beta-carotene and superoxide dismutase activity) and microinflammation (C-reactive protein, leukocytes and neopterin). The proportion of subjects without/positive for one or two MetS RFs was comparable between the groups. From the components of MetS only immunoreactive insulin levels differed significantly (95% CI: omnivores: 5.0-7.1 microU/mL, vegetarians: 4.5-5.4, p = 0.03). Omnivores had lower AOPP (omnivores: 0.29-0.36 micromol/g albumin, vegetarians: 0.36-0.52, p = 0.01) and beta-carotene levels than vegetarians, they consumed more calories, proteins, fat and saturated fatty acids, and less fibres, beta-carotene and vitamin C. Multiple regression analysis revealed vitamin E and AOPP levels as the most important independent determinants of MetS RFs. The vegetarian diet seems to exert beneficial effects on MetS RFs associated microinflammation. Whether the vegetarian diet may counteract the deleterious effects of elevated AOPPs and AGEs, remains to be elucidated.  相似文献   
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Using the antibody response during secondary exposure of rabbits primed with antigens of Trypanosoma evansi as an indirect measure of immunological memory, it was shown that C3 decomplementaemia resulted in a reduced antibody response, with IgM being predominant in the sera samples followed by IgG and then IgA [corrected]. While significant differences were observed in the levels of IgG produced by the C3-depleted and C3-intact rabbits no differences were recorded in the levels of IgM and IgA produced by the two groups after C3 decomplementaemia. These results demonstrate that C3 depletion did not abolish memory of the T. evansi antigen in these rabbits but only modified the magnitude and pattern of their response. The host response to reinfection may be affected by such changes as those observed in this study.  相似文献   
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IL-4 is produced promptly in response to certain infections and plays a key role in the Th1/Th2 T cell dichotomy; however, the cellular source remains a matter of debate. Here we describe the induction of IL-4 in bone marrow cells of normal and RAG-/- mice by both Mycobacterium tuberculosis and its major cell wall glycolipid, lipoarabinomannan. Characterization of the cell type responsible indicated that it was distinct from the NK1+ or CD4+ T cell previously ascribed the function of rapid IL-4 secretion. Cell-sorting experiments identified CD19+/B220+ precursor cells, presumably pre-B cells that produced IL-4 constitutively and whose frequency was rapidly and markedly up-regulated by lipoarabinomannan. Thus, pathogenic mycobacteria and their glycolipids may influence hemopoiesis by rapidly inducing IL-4 secretion in the bone marrow.  相似文献   
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BACKGROUND: To determine the efficacy, safety and tolerability of antidepressants in depressed elderly patients. METHODS: Search for randomized controlled double-blind studies evaluating atypical antidepressants (ATYPs), reversible inhibitors of monoamine oxidase-A, selective serotonin reuptake inhibitors (SSRIs) and tricyclic antidepressants in moderate/severe depressed patients > or = 60 years for > or = four weeks. The random effects model (single-arm; comparative) was used to aggregate efficacy, safety and dropout. RESULTS: No difference in single-arm aggregation of outcomes for four antidepressant classes. Comparative analyses showed no statistical difference between outcomes, except SSRIs had a higher response rate than ATYPs. CONCLUSION: Elderly show no differences in antidepressant class outcomes. LIMITATIONS: Heterogeneity and lack of power. CLINICAL RELEVANCE: There is little advantage for antidepressant classes over another in the aged.  相似文献   
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Reduced bone mineral density (BMD), termed diabetic osteopenia, has been reported in patients with insulin-dependent (Type 1) diabetes mellitus (IDDM). To examine BMD in long-term IDDM patients with normal kidney function, but with different degrees of urinary albumin excretion rate (UAER), compared to that of patients with elevated plasma creatinine, 36 IDDM male patients (mean duration 27 years) were subdivided according to UAER (<30, 30-300, >300, >300 mg 24 h(-1) and plasma creatinine 0.120-0.350 mmol l(-1)) and 15 controls were recruited. BMD was measured by dual energy X-ray absorptiometry and UAER by enzyme linked immunosorbent assay. BMD was normal in IDDM patients with normal UAER and reduced in the femoral neck, the trochanter major, and the Wards triangle in patients with increased UAER (p < 0.01, p < 0.05, p < 0.02). BMD correlated to creatinine clearance in both cortical and cancellous bone sites (p < 0.001, p < 0.0001), and inversely to the levels of plasma PTH (p < 0.0005). We conclude that BMD is normal in long-term IDDM male patients with normal kidney function and normal UAER and reduced in patients with increased UAER. Diabetic osteopenia seems to be a progressive phenomenon related to diabetic nephropathy and associated with the decrease in creatinine clearance and with the resulting rise in plasma PTH.  相似文献   
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高源  方丽  薛贵香 《计算机仿真》2021,38(2):240-243,405
碳排放量一旦超标,会使全球气温升高,导致南北极冰川融化,形成自然灾害.为此提出一种建筑生命周期碳排放评价函数多目标优化算法,通过对建筑物的规划设计、施工阶段、运行维护阶段以及拆除阶段二氧化碳总排放量进行计算,获得排放的碳系数,再找出帕累托最优解集以及帕累托前端,决策者依据实际需求,解决建筑工程内多目标优化问题,最后计算...  相似文献   
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