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31.
Substance abuse and violence among today's youth are at an all time high. Numerous prevention programs have been implemented to address these issues. Not all are successful. Research has found that when schools and communities are involved in the planning of prevention programs, youth are more cognizant of risk factors and of behaviors that strengthen risk factors. The purpose of this study was to assess the emerging needs for prevention and health education among youth, and to identify effective approaches for prevention program development and service delivery in schools and communities. This study surveyed 312 youth prevention specialists, school and community health educators and counselors, and parents in a regional sample of ten states. Results indicated that substance abuse and violence are the two most critical and priority issues in need of comprehensive prevention. Multiple prevention service delivery strategies appropriate to youth, including training, technical assistance, conferencing and networking, needs assessment and evaluation, and information requests are discussed in detail. Implications for prevention programming emphasized reducing risk factors and strengthening protective factors, reaching and motivating youth participation. 相似文献
32.
Alan Balsam PhD RD Nicole Grant MS Beatrice L. Rogers PhD 《Journal of community health》1996,21(1):37-49
The nutritional status of persons with HIV and AIDS [PWAs] is constantly challenged throughout the progression of the illness. Home-delivered meals programs for PWAs are rapidly developing across the country to address this problem among the growing population of people with HIV infection and AIDS. This study examined client socio-demographic characteristics (sex, age, ethnicity), types of services offered by these programs, organizational and financial criteria, and characteristics of survey respondents.Data for this study was obtained from 15 of the 17 known home-delivered meals programs for PWAs in the United States through an original, cross-sectional survey instrument conducted by telephone interview between March 1994 and May 1994.Results from this study show an increase in the number of minority populations who participate in these programs (36% African-American and 12% Hispanic vs. 51% Caucasian), as well as women (17.2%) and children (7%). Geographic location was an important determinant for program eligibility. The number of meals served weekly varied greatly (from 510 to 12,600 per week). Other significant services included nutrition counselling, newsletters, and holiday-basket programs. Enhancing service-delivery systems was one of the more prevalent high-priority concerns cited, especially with regard to food quality and safety.These results show that these programs are catering increasingly to minority populations, women and children, and that they are expanding their services to meet the growing needs of their client populations. These findings suggest that there is a greater need for meals and other home-based services for persons living with HIV and AIDS.This research was supported by the Massachusetts Department of Public Health.He formerly was Director of Elder Health at the Massachusetts Department of Public Health, Boston, MA; he is a founder and serves on the Board of Directors of Community Servings 相似文献
33.
Beatrice M Seddon Geoffrey S Payne Laura Simmons Ruth Ruddle Rachel Grimshaw Siew Tan Alison Turner Florence Raynaud Gavin Halbert Martin O Leach Ian Judson Paul Workman 《Clinical cancer research》2003,9(14):5101-5112
PURPOSE: To perform a Phase I study of SR-4554, a fluorinated 2-nitroimidazole noninvasive probe of tumor hypoxia detected by (19)F magnetic resonance spectroscopy (MRS). EXPERIMENTAL DESIGN: SR-4554 administration, on days 1 and 8, was followed by plasma sampling for pharmacokinetic studies and by three MRS studies performed over 24 h on days 8 and 9. Unlocalized MR spectra were acquired from tumor (10- or 16-cm dual resonant 1H/19F surface coil; 1.5 T Siemens Vision MR system; 2048 transients acquired over 34 min; 1.28-ms adiabatic pulse; repetition time, 1 s). Plasma drug concentrations were measured with a validated high-performance liquid chromatography method. Noncompartmental pharmacokinetic analysis was performed. RESULTS: Eight patients underwent pharmacokinetic studies, receiving doses of SR-4554 of 400-1600 mg/m(2). Peak plasma concentrations increased linearly with the SR-4554 dose (r(2) = 0.80; P = 0.0002). The plasma elimination half-life was relatively short (mean +/- SD, 3.28 +/- 0.59 h), and plasma clearance was quite rapid (mean +/- SD, 12.8 +/- 3.3 liters/h). Urinary recovery was generally high. SR-4554 was well tolerated. A single patient experienced dose-limiting toxicity (nausea and vomiting) at 1600 mg/m(2). The maximum tolerated dose was 1400 mg/m(2). SR-4554 was detected spectroscopically in tumors immediately after infusion at doses of 400-1600 mg/m(2). At the highest dose (1600 mg/m(2)), SR-4554 was detectable in tumor at 8 h, but not at 27 h. CONCLUSIONS: SR-4554 has plasma pharmacokinetic and toxicity profiles suitable for use as a hypoxia probe. It can be detected in tumors by unlocalized MRS. Additional clinical studies are warranted. 相似文献
34.
35.
Ruth Etzioni Sarah Hawley Dean Billheimer Lawrence D True Beatrice Knudsen 《Cancer epidemiology, biomarkers & prevention》2005,14(5):1040-1046
BACKGROUND: Immunohistochemical studies use antibodies to stain tissues with the goal of quantifying protein expression. However, protein expression is often heterogeneous resulting in variable degrees and patterns of staining. This problem is particularly acute in prostate cancer, where tumors are infiltrative and heterogeneous in nature. In this article, we introduce analytic approaches that explicitly consider both the frequency and intensity of tissue staining. METHODS: Compositional data analysis is a technique used to analyze vectors of unit-sum proportions, such as those obtained from soil sample studies or species abundance surveys. We summarized specimen staining patterns by the proportion of cells staining at mild, moderate, and intense levels and used compositional data analysis to summarize and compare the resulting staining profiles. RESULTS: In a study of Syndecan-1 staining patterns among 44 localized prostate cancer cases with Gleason score 7 disease, compositional data analysis did not detect a statistically significant difference between the staining patterns in recurrent (n = 22) versus nonrecurrent (n = 22) patients. Results indicated only modest increases in the proportion of cells staining at a moderate intensity in the recurrent group. In contrast, an analysis that compared quantitative scores across groups indicated a (borderline) significant increase in staining in the recurrent group (P = 0.05, t test). CONCLUSIONS: Compositional data analysis offers a novel analytic approach for immunohistochemical studies, providing greater insight into differences in staining patterns between groups, but possibly lower statistical power than existing, score-based methods. When appropriate, we recommend conducting a compositional data analysis in addition to a standard score-based analysis. 相似文献
36.
Identification
of RAD51–BRCA2 Inhibitors Using N-Acylhydrazone-Based
Dynamic Combinatorial Chemistry
Greta Bagnolini Beatrice Balboni Fabrizio Schipani Dario Gioia Marina Veronesi Francesca De Franco Cansu Kaya Ravindra P. Jumde Jose Antonio Ortega Stefania Girotto Anna K. H. Hirsch Marinella Roberti Andrea Cavalli 《ACS medicinal chemistry letters》2022,13(8):1262
RAD51 is an ATP-dependent recombinase, recruited by BRCA2 to mediate DNA double-strand breaks repair through homologous recombination and represents an attractive cancer drug target. Herein, we applied for the first-time protein-templated dynamic combinatorial chemistry on RAD51 as a hit identification strategy. Upon design of N-acylhydrazone-based dynamic combinatorial libraries, RAD51 showed a clear templating effect, amplifying 19 N-acylhydrazones. Screening against the RAD51–BRCA2 protein–protein interaction via ELISA assay afforded 10 inhibitors in the micromolar range. Further 19F NMR experiments revealed that 7 could bind RAD51 and be displaced by BRC4, suggesting an interaction in the same binding pocket of BRCA2. These results proved not only that ptDCC could be successfully applied on full-length oligomeric RAD51, but also that it could address the need of alternative strategies toward the identification of small-molecule PPI inhibitors. 相似文献
37.
Histopathologic examination and clinical observations of solid and haematological malignancies indicates mast cells as key host cells in the tumour infiltrate, with important consequence on tumour-associated angiogenesis and tumour growth. Data suggest indeed that tumour-infiltrating mast cells may exert a prominent function in the angiogenic "switch", which is essential for the progression of early tumours. The experimental approach has substantially increased our understanding of the role of tumour-infiltrating mast cells in the process of angiogenesis that accompanies tumour development. This review will focus on the crucial contribution of mast cells in promoting tumour neovascularization as it emerges from the most recent observations of experimental carcinogenesis in in vivo and in vitro models. 相似文献
38.
OBJECTIVE: To examine whether clean catch urine specimens correlate with catheterized specimens for determination of protein/creatinine ratios in pregnant women being evaluated for preeclampsia. METHODS: Sixty pregnant women who were at least at 20 weeks of gestation were enrolled. Patients with ruptured membranes, vaginal bleeding, or urinary tract infections were excluded. Midstream clean catch urine specimens were collected. Catheterized specimens were then collected and used for clinical management. The specimens were analyzed for protein, creatinine, urinalysis, and culture. Based on sample size calculations, 60 participants were needed to detect a correlation of 0.90 with 80% power and alpha=0.05. RESULTS: Mean gestational age at enrollment was 35.9 weeks (range 23.1-41.7 weeks). Median (range) clean catch and catheterized protein/creatinine ratios were 0.204 (0.089-3.465) and 0.181 (0.067-3.335), respectively, with a correlation coefficient of 0.897 (P<.001). When results were categorized by degree of proteinuria using a cutoff of 0.3, sensitivity and specificity of the clean catch protein/creatinine ratios were 95.2% and 97.4%. When using a more conservative cutoff of 0.19, sensitivity and specificity of the clean catch protein/creatinine ratios were 96.4% and 75.0%. CONCLUSION: Clean catch and catheterized urine specimens correlate well in women with suspected preeclampsia. Routine catheterization of pregnant women is not necessary in the evaluation of preeclampsia. 相似文献
39.
40.
Annaheim B Rehm J Neuenschwander M Gmel G 《International journal of public health》2007,52(4):233-241
Summary Quitting hash. The readiness for behaviour change among cannabis users in Switzerland.
Objectives: The study aims to identify factors that are associated with the willingness of adolescents and young adults to modify their
cannabis use. It is hypothesized that frequency of use, cannabis-related problems and age of onset are associated with their
willingness to change.
Methods: In 2004, a survey on cannabis use was conducted among 13 to 29 year-olds living in Switzerland. Of the 5025 participants 593
had taken cannabis during the past six months. They were then asked about their willingness to change. Three groups of users
were compared: those not willing to change, those considering change, and those determined to change. Pearson Chi-square-tests
and logistic regressions were performed to test the hypotheses.
Results: Experience of problems motivates users to start thinking about changing their behavior. Frequent use and early onset are associated
with young people not making the transition from considering changing behavior to resolving to do so.
Conclusions: The need to perceive problematic use as a first step towards change and the inhibiting effect of dependencerelated factors
on the transition from consideration to determination calls for tailored intervention approaches that are matched to the willingness
to change.
Eingereicht: 10. Dezember 2005; überarbeitet: 13. September 2006; Angenommen: 6. M?rz 2007 相似文献