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991.
While the Weight Efficacy Lifestyle Questionnaire (WEL) shows promise as a measure of self-efficacy for eating control, there is a lack of research examining the psychometric properties of this measure with ethnic minorities. The current study examined the WEL with a sample of 144 overweight and obese African American females. Analyses indicated similar self-efficacy levels compared to predominantly Caucasian samples. Supporting the validity of the WEL, participants undergoing obesity treatment demonstrated modest improvement in WEL scores, while standard care participants showed no changes in self-efficacy over time. Factor analysis indicated a four-factor structure rather than the five factors previously found. The four-factor structure accounted for 61.85% of the variance. Results indicate the WEL may be a valid measure of self-efficacy for overweight and obese African American women, although researchers should be mindful of the variation in scale properties when using the WEL with this population.  相似文献   
992.
OBJECTIVES: We investigated physicians' delivery of HIV prevention counseling to newly diagnosed and established HIV-positive patients. METHODS: A questionnaire was developed and mailed to 417 HIV physicians in 4 US cities. RESULTS: Overall, rates of counseling on the part of physicians were low. Physicians reported counseling newly diagnosed patients more than established patients. Factors associated with increased counseling included having sufficient time with patients and familiarity with treatment guidelines. Physicians who perceived their patients to have mental health and substance abuse problems, who served more male patients, and who were infectious disease specialists were less likely to counsel patients. CONCLUSIONS: Intervention strategies with physicians should be developed to overcome barriers to providing counseling to HIV-positive patients.  相似文献   
993.
Inconsistent reports of the prevalence of risk perception accuracy may be related to the use of different classification strategies. The purpose of this study was to compare two approaches for assessing the accuracy of women's breast cancer risk perceptions. A telephone survey was conducted with an age-stratified random sample of British Columbian women 20-79 years of age without a breast cancer diagnosis (n = 761). A comparison of two methods employed to determine perception accuracy revealed substantial differences between the methods with regard to the classification of women as under- and over-estimators. The study highlights the need for researchers to consider the method used to determine the accuracy of risk perceptions and the implications of using different strategies to assess risk perception accuracy when such information is used in research or to guide interventions.  相似文献   
994.
BACKGROUND: Patients with end-stage renal disease (ESRD) have significant shifts in fluid homeostasis that may impair measurements of body composition using methods based upon determinations of body water. Estimates of body water are fundamental for bioelectrical impedance analysis (BIA), which measures electrical resistance to estimate total body water and body composition. METHODS: BIA was compared with 2 other techniques: (1) air displacement plethysmography (ADP), which relies on measurements of body density to estimate body fat and fat-free masses; and (2) dual-energy x-ray absorptiometry (DXA), which depends on the relative attenuation of an x-ray beam to produce images of body fat and bone mineral. In study 1, BIA and ADP were performed on 38 ESRD patients (21 men and 17 women; age 51.3 +/- 2.2 years; weight 79.8 +/- 2.9 kg; body mass index [BMI] 27.4 +/- 0.9 kg/m2). In study 2, BIA and DXA were performed on 47 patients (22 men and 25 women; age 52.7 +/- 2.3 years; weight 73.6 +/- 2.9 kg; BMI 25.9 +/- 1.0 kg/m2). RESULTS: The ranges of percent body fat using BIA in studies 1 and 2 were from 7% to 57% and from 6% to 52%, respectively. Percent body fat measurements were significantly (p < .0001) correlated for BIA vs ADP (r = .74) and for BIA vs DXA (r = .84). Mean body fat as determined by BIA and ADP in study 1 was 31.8 +/- 2.0% and 36.3 +/- 1.8%* and by BIA and DXA in study 2 was 29.6 +/- 1.5% and 31.8 +/- 1.8%*, respectively (*p < .05 vs BIA). All 3 methods had similar variability associated with their measurements (coefficients of variation approximately 5%). The average body fat measured by BIA was less than ADP or DXA, regardless of gender or race. Furthermore, the variation was not greater at lower or higher body fat values. CONCLUSIONS: Body fat measurements using ADP and DXA were correlated with those using BIA across a relatively wide range of body fat levels in adults with ESRD. However, BIA appeared to underestimate body fat and overestimate fat-free mass, possibly because of increased measurements of body water. Because ADP is convenient and does not use body water content in determination of body density and body composition, it has very good potential as a relatively new technique to estimate percent body fat in adults with ESRD.  相似文献   
995.
The present work focuses on the use of solid and agricultural residues from Aloe vera crops, as a source of antimicrobial agents and textile dyes. The roots from an A. vera plantation post-harvest were extracted with ethyl acetate, purified and phytochemically characterized to obtain five metabolites: aloesaponarin-I (1), deoxyerythrolaccin (2), lacaic acid D methyl ester (3), aloesaponarin-II (4), and aloesaponol-I (5). Acid hydrolysis of the solid industrial residue gave aloe-emodin (6) as the main product with a good yield. All of the components were tested for the first time against phytopathogenic bacteria strains, and deoxyerythrolaccin and lacaic acid D methyl ester were active against Xanthomonas campestris with MIC values of 46.86 and 93.75 μg/mL, respectively. Aloesaponarin-I and aloe-emodin, the main products, were tested as dyes for polyester fabrics using different mordants and pH bath conditions. The colour of each material was investigated in terms of the CIELAB L*, a* and b* values, and the colour fastness to light and washing was investigated according to the Mexican standard methods (NMX-A-074-INNTEX-2005; NMX-A-105-B02-INNTEX-2010). Aloesaponarin-I dyed polyester bright yellow but the final colour was very sensitive to the pH of the dye bath. Aloe-emodin dyed polyester deep yellow, and the fabrics showed good colour fastness to light and to domestic laundering. This study provides evidence that the phenolic components obtained from agricultural residues of the aloe industry can be useful organic alternatives as antimicrobial agents and textile dyes.  相似文献   
996.

Background

There is limited information about the potential individual-level and contextual drivers of heavy drinking in South Africa. This study aimed to identify risk factors for heavy drinking in Tshwane, South Africa.

Methods

A household survey using a multi-stage stratified cluster random sampling design. Complete consumption and income data were available on 713 adults. Heavy drinking was defined as consuming ≥120?ml (96?g) of absolute alcohol (AA) for men and?≥?90?ml (72?g) AA for women at any location at least monthly.

Results

53% of the sample were heavy drinkers. Bivariate analyses revealed that heavy drinking differed by marital status, primary drinking location, and container size. Using simple logistic regression, only cider consumption was found to lower the odds of heavy drinking. Persons who primarily drank in someone else’s home, nightclubs, and sports clubs had increased odds of heavy drinking. Using multiple logistic regression and adjusting for marital status and primary container size, single persons were found to have substantially higher odds of heavy drinking. Persons who drank their primary beverage from above average-sized containers at their primary location had 7.9 times the odds of heavy drinking as compared to persons who drank from average-sized containers. Some significant associations between heavy drinking and age, race, and income were found for certain beverages.

Conclusion

Rates of heavy drinking were higher than expected giving impetus to various alcohol policy reforms under consideration in South Africa. Better labeling of the alcohol content of different containers is needed together with limiting production, marketing and serving of alcohol in large containers.
  相似文献   
997.
Objectives Studies examining risk factors for preterm birth (PTB) such as psychosocial stress are often focused on women with a history of PTB; however, most preterm babies are born to women with no history of preterm birth. Our objective was to determine if the relationship between psychosocial stress and PTB is altered by parity. Non-Hispanic black (NHB) women have increased psychosocial stress and PTB; therefore, we further aimed to determine if race alters the relationship between psychosocial stress, parity, and PTB. Methods We performed a secondary analysis of the Healthy Pregnancy, Healthy Baby Study comparing pregnant women who were primiparous (first pregnancy), multiparous with history of preterm birth, or multiparous with history of term birth. Perceived stress, perceived racism, interpersonal support, John Henryism and self-efficacy were measured using validated instruments. Logistic regression was used to model the effect of psychosocial stress on PTB stratified by parity and race. Results The analysis entire cohort included 1606 subjects, 426 were primiparous, 268 had a history of presterm birth, and 912 had a history of term birth. In women with a history of term birth, higher self-efficacy was associated with lower odds of spontaneous PTB, and this association was amplified in NHB women. In women with a history of spontaneous PTB, John Henryism Active Coping was associated with lower odds of spontaneous PTB in the index pregnancy. Conclusions for Practice The relationship between psychosocial stress and PTB may be mediated by parity and race.  相似文献   
998.
999.
1000.

Objectives

Sarcopenia is a common geriatric syndrome, whose diagnosis implies the assessment of muscle mass. Dual-energy x-ray absorptiometry (DXA) is the reference method for clinical practice, but it is not universally available. We compared DXA with 2 anthropometry-based methods to assess muscle mass in older adults.

Design

Cross-sectional.

Setting

Ambulatory patients.

Participants

148 (87 female and 61 male) white older adults.

Measurements

Mid-arm muscle circumference (MAMC), whole skeletal muscle mass estimated by the Lee's formula (eTSMM), and relative skeletal muscle index (RSMI).

Results

Men and women did not differ for MAMC and RSMI, whereas eTSMM was higher (P < .001) in men. MAMC and eTSMM correlated with RSMI, in the whole sample as in men and women separately (P < .001). According to the McNemar test, the frequencies of older men and women with low muscle mass identified by eTSMM did not differ from those detected by RSMI (P = .066) at variance with MAMC. Using EWGSOP (European Working Group on Sarcopenia in Older People) criteria for RSMI as standard reference, the receiver operating characteristic (ROC) curves provided redefined cut-offs of reduced muscle mass: 18.6 cm in women and 22.3 cm in men for MAMC, and 17.7 kg in women and 28.3 kg in men for eTSMM. The areas under the ROC curves (AUCs) for MAMC were 0.882 in women (sensitivity 89%, specificity 84%) and 0.826 in men (sensitivity 94%, specificity 67%). The AUCs for eTSMM were 0.8913 in women (sensitivity 95%, specificity 81%) and 0.878 in men (sensitivity 97%, specificity 67%). No significant difference was found between the ROC curves of MAMC and eTSMM in both sexes.

Conclusion

Two simple anthropometric methods, possibly used in every clinical setting, could be valuable screening tools for low muscle mass in older subjects.  相似文献   
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