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51.
Our objective was to identify individual- and school-level contextual factors related to adherence to the recommendations for physical activity in adolescents. The study used a representative sample of 15,902 students from 328 schools aged 11–18 years participating in the Spanish Health Behaviour in School-aged Children (HBSC) survey 2006. In addition to the student questionnaire, the school management board completed a questionnaire about school-based policies related to physical activity. Adherence to the recommendations was defined as “having carried out moderate and/or vigorous physical activity for at least 60 min a day on five or more days during the last week”. Analysis was undertaken using multilevel logistic regression models. Individual factors associated in a statistically significant way with a higher non-compliance were: being female; being older; immigrants; tobacco smoking; being overweight or obese; low consumption of fruit and vegetables; low level of satisfaction with life; not having a high level of academic achievement; and spending a lot of time studying. The family variables were: not undertaking sports activities with the family; low socioeconomic status; and a low level of satisfaction with family relationships. Compared with schools that have a low level of policies to promote physical activities, those with a high level of promotion had an odds ratio of 0.76 (CI 95 %, 0.61–0.94). In summary, irrespective of personal and family factors, students from schools with better policies of promotion of physical activity showed a higher compliance with the recommendations.  相似文献   
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By introducing bulky 2-phenylethyl groups into sulfur-rich electron acceptors, 5,5′-bithiazolidinylidene-2,2′-dione-4,4′-dithione and 5,5′-bithiazolidinylidene-2,4,2′,4′-tetrathione, electron transport with the mobility of 0.27 cm2 V−1 s−1 with ambient and long-term stability is achieved in thin-film transistors. Bulky groups destroy the intermolecular S–S network, but the long-term transistor stability is maintained. Here, benzyl groups realize one-dimensional stacking structures, whereas 2-phenylethyl groups lead to herringbone structures.

Performance and long-term air stability of birhodanine-based n-channel transistors are improved by introducing phenylethyl moieties.  相似文献   
53.
AIDS and Behavior - Pre-exposure prophylaxis (PrEP) is highly effective in preventing HIV but requires sustained adherence. Conditional economic incentives (CEIs) can improve medication-taking...  相似文献   
54.
Anderson–Fabry disease is a rare, X-chromosomal lipid storage disorder caused by a deficiency of lysosomal -galactosidase A. Clinical manifestations of Anderson–Fabry disease include excruciating pain in the extremities (acroparaesthesia), skin vessel ectasia (angiokeratoma), corneal and lenticular opacity, cardiovascular disease, stroke and renal failure, only renal failure being a frequent cause of death. Heterozygote female carriers have often been reported as being asymptomatic or having an attenuated form of the disease. To evaluate the spectrum of clinical signs in heterozygotes, a comprehensive clinical examination was performed on 20 carriers of Anderson–Fabry disease. This revealed that, in addition to the skin manifestation, various other clinical manifestations of the disease are present, including acroparaesthesia, kidney dysfunction, cerebrovascular disease, and gastrointestinal and heart problems. It therefore appears that Anderson–Fabry disease affects both hemizygotes and heterozyotes and therefore should be considered to be an X-linked dominant disease.  相似文献   
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We evaluated the effect of salvage antiretroviral therapy with lopinavir/ritonavir (LPV/r) on the immune system of heavily antiretroviral pretreated HIV-infected children. We carried out a longitudinal study in 20 antiretroviral experienced HIV-infected children to determine the changes in several immunological parameters (T cell subsets, thymic function) every 3 months during 18 months of follow-up on salvage therapy with LPV/r. Statistical analyses were performed with the Wilcoxon test, taking as a reference the basal value at the entry in the study. HIV-infected children showed an increase of CD4+ T cells, a decrease in CD8+ T cells, and an increase in T cell rearrangement excision circle (TRECs) levels. The percentage of HIV children with undetectable viral load (VL < or = 400 copies/ml) increased significantly (p = 0.007) and the percentage with SI viral phenotype decreased significantly (p = 0.002) at the end of the study. Thus, the viral phenotype changed to NSI/R5 after salvage therapy with LPV/r. Interestingly, we observed a significant decrease of memory (CD4+ CD45RO+) and a moderate decrease of activated (CD4+ HLA-DR+, CD4+ HLA-DR+CD38, CD4+, CD45RO+HLA-DR+) CD4+ T cells during the follow-up. On the other hand, memory (CD8+ CD45RO+ and CD8+ CD45RO+CD38+), activated (CD8+ HLA-DR+CD38+, CD8+ HLA-DR+, CD8+ CD38+), and effector (CD8+ CD57+, CD8+ CD28(-)CD57+) CD8+ T cells had a very significant decrease during follow-up. Our data indicate an immune system reconstitution in heavily pretreated HIV-infected children in response to salvage therapy with LPV/r as a consequence of a decrease in immune system activation and an increase in thymic function.  相似文献   
58.
We describe 16 HIV-infected patients with disseminated histoplasmosis (14 men, mean age 28 +/- 7.84 years), diagnosed at Hospital Eva Perón in Argentina during the period of October 1993 to July 2000. Disseminated histoplasmosis occurred in 5.3% of HIV-infected patients over the study period. The main symptoms included fever, weight loss and hepatosplenomegaly in 93.8%. Other relevant findings were respiratory compromise (56.3%), digestive symptoms (43.8%), mucocutaneous lesions (75%) and multiple lymphadenopathy (69%). Treatment consisted of amphotericin B 1 mg/kg/day up to a total dose of 1 g, followed by 400 mg/day of oral itraconazole. Mortality in the acute phase was 19% and 37.5% of patients relapsed.  相似文献   
59.
AIMS: Functional mitral regurgitation (MR) and myocardial asynchronism occur commonly in patients with dilated cardiomyopathy and affect adversely their prognosis and symptoms. The aim of this study was to evaluate the mechanisms of changes in MR severity during dynamic exercise in patients with chronic heart failure (CHF). METHODS AND RESULTS: Seventy patients with CHF due to left ventricular (LV) systolic dysfunction [LV ejection fraction (EF) <40%] and functional MR were studied. All were in sinus rhythm. Medications were left unchanged for the study. Each patient performed a maximal symptom-limited exercise test with continuous 2D-Doppler echocardiography. Mitral regurgitant volume (RV) and effective regurgitant orifice (ERO) were determined at rest and during exercise. LV asynchrony using Doppler tissue imaging and interventricular asynchrony using conventional pulsed-Doppler were evaluated at rest. Resting LV EF averaged 25+/-8%. Mean resting LV and interventricular mechanical delays were 56+/-50 and 43+/-37 ms, respectively. The overall median values for mitral ERO and RV did not significantly change during dynamic exercise (11 [7-16] vs. 11 [6-21] mm2 and 14 [10-22] vs. 12 [9-23] mL, respectively). However, changes in mitral ERO and RV were individually variable and significantly correlated with the degree of LV asynchronism (r=0.66, P<0.0001 and r=0.66, P<0.0001, respectively). CONCLUSION: Changes in MR are variable during dynamic exercise. LV asynchronism at rest substantially contributes to worsening of functional MR during dynamic exercise in patients with CHF due to LV systolic dysfunction.  相似文献   
60.
The document "Cholesterolemia Control in Spain, 2000: A Tool for Cardiovascular Disease Prevention" reviews the current evidence on cardiovascular disease prevention and the therapeutic advances achieved in recent years, in order to aid risk-based clinical decision-making. Cardiovascular diseases rank as the first cause of death in Spain. Their demographic, health and social impact is increasing and it is likely to continue to do so in the next decades. Appropriate treatment for high blood cholesterol and other major risk factors is crucial in cardiovascular disease prevention. Individual risk stratification is essential to determine follow-up periodicity and treatment. Priorities for the control of cholesterolemia and the consequent cardiovascular risk are based on risk stratification. In primary prevention, the therapeutic objective in high risk patients has been established as LDL-cholesterol < 130 mg/dl. In secondary prevention, drug treatment is indicated when LDL-cholesterol > or = 130 mg/dl and the therapeutic objective is LDL-cholesterol < 100 mg/dl. Statins are first line drugs for treatment of high blood cholesterol. In moderate-severe hypertriglyceridemia or low HDL-cholesterol, fibrates are preferred. In acute coronary syndrome, hypolipemiant treatment, should be started as soon as possible, when indicated. Secondary prevention programmes that continually provide good clinical and risk factor control should be provided to coronary heart disease patients.  相似文献   
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