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1.
A questionnaire survey was carried out among 1041 students in secondary schools and colleges in Dar-es-Salaam, Tanzania to evaluate the relationship between HIV-risky sexual behaviour and anti-condom bias, as well as with AIDS-related information, knowledge, perceptions and attitudes. Self-reportedly, 54% of students (75% of the boys and 40% of the girls) were sexually active, 39% had a regular sexual partner and 13% had multiple partners in the previous year. The condom use rate was higher than previous reports. However, 30% of sexually active respondents did not always use condoms (Risk-1 behaviour) and 35% of those with multiple partners in the previous year did not always use condoms (Risk-2 behaviour). Multiple logistic regression analyses indicated that 'sex partner hates condom' had association with both Risk-1 behaviour (OR 2.47; 95% CI 1.58-3.85) and Risk-2 behaviour (OR 2.47; 95% CI 1.10-5.48). 'Use of condom prevents HIV infection' also had association with both Risk-1 behaviour (OR 2.09; 95% CI 1.19-3.67) and Risk-2 behaviour (OR 3.73; 95% CI 1.28-11.03). Students engaging in risky behaviour were aware of the risk, even though they failed to change their behaviour. Reasons for the AIDS epidemic among Tanzanian students and the importance of more effective AIDS education are also discussed.  相似文献   
2.
Fracture risk is influenced by both bone strength and by falls. Measures of physical function and performance are predictors of falls. However, the interrelationships among bone mineral density (BMD), regular physical activity, and measures of physical performance are not well known. We studied 447 community-dwelling Japanese people aged 40 years and over (96 men and 351 women) to examine the association of calcaneus BMD with measures of physical performance (grip strength, walking speed, chair stand, and functional reach) and regular physical activity. Calcaneus BMD decreased with age by approximately 25% in men and 42% in women. Measures of physical performance decreased with age by approximately 30% in both genders, however, performance on the chair stand test declined by approximately 60%. There were only minimal differences in performance measures and calcaneus BMD between people with and those without regular physical activity in both genders, and most differences were not significant. However, there were significant BMD increases of 3–6% per standard deviation (SD) increase in all performance measures for women and a 7% increase in BMD per SD increase in grip strength for men, after adjusting for age. These associations remained after additional adjustment for body mass index and regular physical activity. These findings suggest that bone density and physical function decline markedly in both men and women with age, and that low BMD and poor function tend to occur together, which would increase fracture risk more than either risk factor alone. Received: 9 August 1999 / Accepted: 4 February 2000  相似文献   
3.
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Chitosan (CS), as a natural polymer, has received a great deal of attention as a carrier for delivery of...  相似文献   
4.
The aim of the present work was to develop a mucoadhesive controlled-release formulation of danazol-sulfobutylether 7 beta-cyclodextrin (SBE 7) complex and to evaluate the feasibility of improving the bioavailability of danazol via the buccal route. Different types of polymers, polycarbophil (PC) and hydroxypropylmethyl cellulose (HPMC) were mixed with danazol-SBE 7 complex and compressed into tablets. These tablets were evaluated for their dissolution and mucoadhesion properties and for drug absorption in female beagle dogs. Increased mucoadhesion was observed for PC-containing tablets compared with HPMC tablets. As the concentration of polymer increased, drug release decreased, and PC-containing tablets gave slower release compared to HPMC tablets. In vivo bioavailability performed in dogs showed that the perorally administered danazol-SBE 7 complex and the danazol-SBE 7 (in PC matrix) buccal tablets had absolute bioavailabilities of 64% and 25%, respectively, that are significantly greater than 1.8% observed for the commercial formulation Danocrine. The increased bioavailability was attributed to the enhanced solubility consequent to complexation, and the possible avoidance of first-pass metabolism upon buccal administration.  相似文献   
5.
The degree of III-CaSO4 to II-CaSO4 transition was estimated on wet specimens, 25 mm in diameter and 50 mm high, prepared from a gypsum-bonded investment for quick casting. After 30 min from mixing the specimens were heated in a 700 degrees C furnace until a specimen temperature of 200 degrees C to 700 degrees C was reached. The estimation was made by measuring mass changes of the specimens before and after heating. The transition reached 39% at 350 degrees C. The same estimation method, when applied to a previous study, showed no transition to this temperature in dry specimens heated slowly (5 degrees C/min). The large difference in transition found between the wet and dry specimens was attributed to the formation of alpha- and beta-hemihydrate, respectively. At 350-450 degrees C, the transition was 3% and 48%, respectively. The pronounced latter transition, generally identified by differential thermal analysis of gypsum, appears as the major investment shrinkage demonstrating its dry dehydration process.  相似文献   
6.
BACKGROUND: Data on body composition of American-born Japanese (Japanese-Americans) are scarce. Studies on differences of body composition between Japanese-Americans and Japanese nationals at various stages of life as well as at various times of measurements are useful for understanding the impact of lifestyle changes on body composition in the two societies. AIM: To see the differences in body size and composition between young adult Japanese-Americans and Japanese nationals. SUBJECTS AND METHODS: Body size and composition of 50 Japanese-Americans consisting of 28 males and 22 females ranging in age from 18 to 23 years were compared with Japanese nationals matched for age and height. Body composition was measured using the underwater weighing method. The study was conducted in the 1980s in the USA and Japan. RESULTS: The average percentage body fat of males was 13.7% for both Japanese-Americans and Japanese nationals, and that of females was approximately 24% for both groups, even though Japanese-American males and females had significantly greater body weight, fat-free mass, and body mass index than Japanese nationals. CONCLUSION: Although young adult Japanese-Americans showed larger body size than Japanese nationals, their percentage fat did not differ at this stage of life in the 1980s.  相似文献   
7.
PURPOSE: We evaluated associations between excess body fat (%Fat) and various indices of obesity calculated from height and weight data. METHODS: In 147 adult males, %Fat was measured by the underwater-weighing method, and obesity indices were generated by the following 5 approaches: the Broca-Katsura (Katsura method), the Kato-Wataya (Kato method), Japan Society for the Study of Obesity (BMI method; based on the body weight at which the BMI is 22), and the Meiji Life Insurance Co. methods, and the Tables and Figures for Assessment of Obesity and Leanness published by the Ministry of Health and Welfare (MHW method). RESULTS: %Fat was 20% or more (obese) in 67 males (45.6%), 15-20% in 39 (26.5%), 10-15% in 35 (23.8%), and less than 10% in 6 (4.1%). The correlation coefficients between the obesity indices and %Fat were 0.612 for the Katsura method, 0.590 for the Kato-method, 0.611 for the BMI method, 0.612 for the Meiji Life Insurance Co. method, and 0.550 for the MHW method, being significant in each case (P < 0.01). When the cut-off point was set as 110% for each obesity index, sensitivity was highest with the Kato-method (82.1%), and specificity was highest with the Meiji Life Insurance Co. method (93.8%). With the MHW method, the receiver operating characteristic (ROC) curve was slightly farther from the point of sensitivity of 100% and 1-specificity of 0% than the others. CONCLUSION: Excess fat accumulation can not be accurately assessed by obesity indices calculated from body height and weight data. Validity was similar among obesity indices examined.  相似文献   
8.
The relationship between blood pressure and urinary sodium-to-potassium (Na/K) ratio was assessed in eight healthy men, none of whom used antihypertensive medications. Blood pressure and urinary sodium and potassium concentrations were measured for 11 to 33 days without any dietary restriction. For two of the eight subjects, the urinary Na/K ratio significantly correlated with systolic blood pressure (r=0.70 and 0.45, respectively), and in one of the two subjects, the urinary ratio also positively correlated with diastolic blood pressure (r=0.72). In the others, no relationship between the ratio and blood pressure was observed (r=-0.24 to 0.26). The results indicate that, in some individuals, the daily variation of urinary Na/K ratio is closely correlated with day-to-day changes in blood pressure level, and suggest that the urinary Na/K ratio is useful in the management of the daily sodium and potassium intake balance of hypertensive patients who need to restrict salt intake.  相似文献   
9.
OBJECTIVE: We hypothesised that acute ischemic left ventricular failure is characterised by depressed systolic and diastolic function combined with inefficiency in oxygen to mechanical work energy transfer. METHODS: Eight anaesthetised pigs (32+/-3 kg) were employed in an in vivo open chest model. Intraventricular combined pressure and conductance catheters were used to generate continuous left ventricular pressure-volume relations. Myocardial oxygen consumption (MVO(2)) was determined from coronary flow and coronary arteriovenous oxygen difference. After baseline measurements, ischemia was induced by repeated left coronary injections of 50 microm polystyrene microspheres until stroke volume was reduced by 30%. Haemodynamic and biochemical measurements were repeated 30, 90 and 150 min after microembolisation. RESULTS: Coronary embolisation induced a significant reduction in stroke work (2749+/-504-1473+/-449 mmHg ml, P<0.05) at 30 min compared to baseline. Post-embolic contractility was reduced measured by the slope of the preload recruitable stroke work index (66.2+/-12.8-50.0+/-5.8 mmHg, P<0.05) and the slope of the curvilinearly fitted end-systolic pressure-volume relation in V(0) (7.1+/-2.2-4.9+/-2.2 mmHg/ml, P<0.05). The dP/dt(min) decreased (2076+/-291-1468+/-266 mmHg/s, P<0.05), but there was no significant change in diastolic stiffness or Tau. Following the 30 min measurements, there were only small changes in most indices. We found no change in myocardial oxygen consumption for basal metabolic processes or excitation-contraction coupling (unloaded MVO(2)), and there were no changes in conversion of oxygen to total mechanical work (MVO(2)-PVA slope). However, decreased mechanical efficiency (SW/MVO(2)) paralleled an increased ratio of arterial elastance to ventricular elastance. CONCLUSIONS: Coronary microembolisation in pigs induce a stable ischemic left ventricular failure characterised by reduced contractility and minimally impaired diastolic function. In this acute ischemic left ventricular failure, the main contributor to all over cardiovascular inefficiency is increased ratio of arterial- to ventricular elastance, a setting that impairs mechanical efficiency. However, efficiency of oxygen to total mechanical work transfer in the myocardium is unaltered. The mechanism behind this finding is elusive and warrants further investigation.  相似文献   
10.
Psychopathy is a serious psychiatric phenomenon characterized by a pathological constellation of affective (e.g., callous, unemotional), interpersonal (e.g., manipulative, egocentric), and behavioral (e.g., impulsive, irresponsible) personality traits. Though amygdala subregional defects are suggested in psychopathy, the functionality and connectivity of different amygdala subnuclei is typically disregarded in neurocircuit‐level analyses of psychopathic personality. Hence, little is known of how amygdala subregional networks may contribute to psychopathy and its underlying trait assemblies in severely antisocial people. We addressed this important issue by uniquely examining the intrinsic functional connectivity of basolateral (BLA) and centromedial (CMA) amygdala networks in relation to affective, interpersonal, and behavioral traits of psychopathy, in conduct‐disordered juveniles with a history of serious delinquency (N = 50, mean age = 16.83 ± 1.32). As predicted, amygdalar connectivity profiles exhibited dissociable relations with different traits of psychopathy. Interpersonal psychopathic traits not only related to increased connectivity of BLA and CMA with a corticostriatal network formation accommodating reward processing, but also predicted stronger CMA connectivity with a network of cortical midline structures supporting sociocognitive processes. In contrast, affective psychopathic traits related to diminished CMA connectivity with a frontolimbic network serving salience processing and affective responding. Finally, behavioral psychopathic traits related to heightened BLA connectivity with a frontoparietal cluster implicated in regulatory executive functioning. We suggest that these trait‐specific shifts in amygdalar connectivity could be particularly relevant to the psychopathic phenotype, as they may fuel a self‐centered, emotionally cold, and behaviorally disinhibited profile. Hum Brain Mapp 37:4017–4033, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.  相似文献   
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