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971.
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   
972.
Children of farmworkers can be exposed to pesticides through multiple pathways, including agricultural take-home and drift as well as residential applications. Because farmworker families often live in poor-quality housing, the exposure from residential pesticide use may be substantial. We measured eight locally reported agricultural pesticides and 13 pesticides commonly found in U.S. houses in residences of 41 farmworker families with at least one child < 7 years of age in western North Carolina and Virginia. Wipe samples were taken from floor surfaces, toys, and children's hands. We also collected interview data on possible predictors of pesticide presence, including characteristics of the household residents, cleaning practices, and characteristics of the home. All families were Spanish-speaking, primarily from Mexico. Results indicate that six agricultural and 11 residential pesticides were found in the homes, with agricultural, residential, or both present in 95% of homes sampled. In general, residential pesticides were more commonly found. Presence of both types of pesticides on the floor was positively associated with detection on toys or hands. Agricultural pesticide detection was associated with housing adjacent to agricultural fields. Residential pesticide detection was associated with houses judged difficult to clean. Although the likelihood of agricultural pesticide exposure has been considered high for farmworker families, these results indicate that residential pesticide use and exposure in this population merit further study.  相似文献   
973.
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   
974.
BACKGROUND: Extensive studies have revealed the importance of a healthy lifestyle and the role of each lifestyle factor in health. However, lifestyle factors have rarely been studied simultaneously. The authors propose an integrated approach to summarize total healthfulness of lifestyles and to enhance understanding of lifestyle patterns across countries. METHODS: The authors created an overall measure of lifestyle called the Lifestyle Index (LI), integrating diet, physical activity, smoking, and alcohol use to provide a global tool of monitoring healthfulness and patterns of lifestyles. Using the LI, the authors conducted a cross-national comparison between China (n = 8352) and the United States (n = 9750). RESULTS: The LI effectively reflected the healthfulness of lifestyle components in both countries. The mean of the LI scores was slightly higher in China than the US. Scores of diet quality, physical activity, and smoking were higher in China, but scores of alcohol behavior were higher in the US. Similar lifestyle patterns but different unhealthy behaviors were identified in these countries. CONCLUSIONS: An assessment of total healthfulness of lifestyles and a better understanding of lifestyle patterns across countries using the LI can provide practical guidance to developing and targeting public health promotion activities to improve global public health.  相似文献   
975.
We examined the association between residential proximity to agricultural pesticide use and breast cancer incidence among members of the California Teachers Study cohort, a large study of professional school employees with extensive information on breast cancer risk factors, followed for cancer incidence since 1995. We identified 1552 invasive breast cancer cases, diagnosed between 1996 and 1999, among 114,835 cohort members. We used California Pesticide Use Reporting data to select pesticides for analysis based on use volume, carcinogenic potential, and exposure potential; a Geographic Information System was used to estimate pesticide applications within a half-mile radius of subjects' residences. We applied Cox proportional hazard models to estimate hazard rate ratios (HR) for selected pesticides, adjusting for age, race, and socioeconomic status. We saw no association between residential proximity to recent agricultural pesticide use and invasive breast cancer incidence. HR estimates for the highest compared to the lowest exposure categories for groups of agents were as follows: probable or likely carcinogens (1.07, 95% confidence interval (CI): 0.86-1.32), possible or suggestive carcinogens (1.06, 95% CI: 0.87-1.29), mammary carcinogens (1.15, 95% CI: 0.90-1.48), and endocrine disruptors (1.03, 95% CI: 0.86-1.25). HR estimates for other groups and individual pesticides did not differ from unity, nor was there a trend for any groupings of or individual pesticides examined. Stratifying by menopausal status or family history of breast cancer did not substantially affect our results. Our analyses suggest that breast cancer incidence is not elevated in areas of recent, high agricultural pesticide use in California.  相似文献   
976.
Although popular and effective for weight loss, low-carbohydrate, high-protein, high-fat (Atkins) diets have been associated with adverse changes in blood and renal biomarkers. High-protein diets low in fat may represent an equally appealing diet plan but promote a more healthful weight loss. Healthy adults (n = 20) were randomly assigned to 1 of 2 low-fat (<30% energy), energy-restricted groups: high-protein (30% energy) or high-carbohydrate (60% energy); 24-h intakes were strictly controlled during the 6-wk trial. One subject from each group did not complete the trial due to out-of-state travel; two subjects in the high-carbohydrate group withdrew from the trial due to extreme hunger. Body composition and metabolic indices were assessed pre- and post-trial. Both diets were equally effective at reducing body weight (-6%, P < 0.05) and fat mass (-9 to -11%, P < 0.05); however, subjects consuming the high-protein diet reported more satisfaction and less hunger in mo 1 of the trial. Both diets significantly lowered total cholesterol (-10 to -12%), insulin (-25%), and uric acid (-22 to -30%) concentrations in blood from fasting subjects. Urinary calcium excretion increased 42% in subjects consuming the high-protein diet, mirroring the 50% increase in dietary calcium with consumption of this diet; thus, apparent calcium balance was not adversely affected. Creatinine clearance was not altered by diet treatments, and nitrogen balance was more positive in subjects consuming the high-protein diet vs. the high-carbohydrate diet (3.9 +/- 1.4 and 0.7 +/- 1.7 g N/d, respectively, P < 0.05). Thus, low-fat, energy-restricted diets of varying protein content (15 or 30% energy) promoted healthful weight loss, but diet satisfaction was greater in those consuming the high-protein diet.  相似文献   
977.
978.
The process for continuous improvement of the TNM classification   总被引:17,自引:0,他引:17  
The TNM classification is a worldwide benchmark for reporting the extent of malignant disease and is a major prognostic factor in predicting the outcome of patients with cancer. The objectives for cancer staging were defined by the International Union Against Cancer (UICC) TNM Committee almost 50 years ago and are still broadly applicable today. To keep pace with the modern demands of evidence-based practice, the UICC introduced a structured process for introducing changes to the TNM classification. The elements of the TNM process were determined to include the development of unambiguous criteria for the information and documentation required to consider changes in the classification, establishment of a well-defined process for the annual review of relevant literature, formation of site-specific expert panels, and the participation of experts from all over the world in the TNM review process. Communication between the oncology community and those involved in the TNM classification was established as being essential to the success of the process. The process, which was introduced in 2002, will be tested over the next 3-4 years and evaluated. In addition to the formal process, individual initiative, involvement by the national staging committees, and group consensus are required. Furthermore, increased involvement by the experts should improve the understanding and dissemination of the TNM classification.  相似文献   
979.
BACKGROUND: To redirect cytotoxic T cells to target a broad range of adenocarcinomas, the authors constructed a novel, recombinant, bispecific antibody, E3Bi, directed at the tumor-associated antigen, epithelial cell adhesion molecule (EpCAM), and the CD3 receptor on T cells. METHODS: T cells were prepared from healthy blood donors. The cytotoxicity of activated T cells (ATC) redirected to tumor cells by E3Bi was measured with in vitro (51)Cr release assays. In vivo studies were performed in a severe combined immunodeficient (SCID)/Beige mouse xenograft model. Tumor-bearing mice were treated with low doses (1 mg/kg) or high doses (10 mg/kg) of E3Bi along with ATC (2 x 10(9) cells/kg), and treatment efficacy was evaluated both by ex vivo tumor cell survival assay after in vivo treatments and by in vivo tumor growth delay studies. RESULTS: In vitro, targeting the EpCAM-overexpressing human tumor cell lines with E3Bi increased specific cytotoxicity of ATC by > 70% at an effector-to-target ratio of 2.5 (P < 0.001); this cytotoxicity was abolished competitively in the presence of an anti-EpCAM monoclonal antibody. In contrast, E3Bi did not enhance ATC cytotoxicity toward the low EpCAM-expressing tumor cell line. In ex vivo tumor cytotoxicity assays, a significant reduction in tumor cell survival (40% with low-dose E3Bi; 90% with high-dose E3Bi) was observed in E3Bi/ATC-treated mice compared with control mice that were treated with ATC only. In addition, SCID/Beige mice xenografted with LS174T tumors demonstrated a significant tumor growth delay (P = 0.0139) after receiving E3Bi/ATC/interleukin 2 (IL-2) compared with mice that received ATC/IL-2 alone. CONCLUSIONS: E3Bi specifically and very efficiently redirected T cells to destroy EpCAM-overexpressing tumors both in vitro and in an animal model. These results suggest a therapeutic utility for E3Bi in the treatment of adenocarcinomas.  相似文献   
980.
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