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排序方式: 共有7043条查询结果,搜索用时 15 毫秒
131.
Implementing HIV voluntary counselling and testing (VCT) in bathhouses is a proven public health strategy for reaching high-risk men who have sex with men (MSM) and efficiently identifying new HIV cases. However, some bathhouse managers are concerned that VCT programmes could adversely affect business. This study examined whether offering VCT on the premises of a bathhouse changed patterns of patron visits. A collaborating bathhouse provided electronic anonymized patron data from their entire population of attendees. VCT was offered on premises with varying frequencies over the course of three years. Club entrances and exits were modelled as a function of intensity of VCT programming. Club entrances did not differ as a function of how many days per week testing was being offered in a given month. Additionally, club entrances did not decrease, nor did club exits increase, during specific half-hour time periods when testing was offered. Implementing bathhouse-based VCT did not have any demonstrable impact on patronage. Public health officials can leverage these results to help alleviate club managers' concerns about patron reactions to providing testing on site, and to support expanding sexual health programmes for MSM in these venues. 相似文献
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Genomic profiling in nuclear receptor-mediated toxicity 总被引:1,自引:0,他引:1
Nuclear receptors (NRs) are attractive drug targets due to their role in regulation of a wide range of physiologic responses. In addition to providing therapeutic value, many pharmaceutical agents along with environmental chemicals are ligands for NRs and can cause adverse health effects that are directly related to activation of NRs. Identifying the molecular events that produce a toxic response may be confounded by the fact that there is a significant overlap in the biological processes that NRs regulate. Microarrays and other methods for gene expression profiling have served as useful, sensitive tools for discerning the mechanisms by which therapeutics and environmental chemicals invoke toxic effects. The capability to probe thousands of genes simultaneously has made genomics a prime technology for identifying drug targets, biomarkers of exposure/toxicity and key players in the mechanisms of disease. The complex intertwining networks regulated by NRs are hard to probe comprehensively without global approaches and genomics has become a key technology that facilitates our understanding of NR-dependent and -independent events. The future of drug discovery, design and optimization, and risk assessment of chemical toxicants that activate NRs will inevitably involve genomic profiling. This review will focus on genomics studies related to PPAR, CAR, PXR, RXR, LXR, FXR, and AHR. 相似文献
137.
OBJECTIVES: The purpose of this study was to examine the pattern of and factors that influence hot flash severity across the menopausal transition (MT) and early postmenopause (PM). METHODS: Women from the Seattle Midlife Women's Health Study (N=302) provided data for these analyses: at least one annual health questionnaire and a menstrual calendar. A subset of women provided a first morning voided urine specimen from 1997 through 2005. Urine samples were assayed for estrone glucuronide and FSH. Linear mixed effects modeling was used to identify change in hot flash severity scores over time, including the relationship to age, MT-related, psychosocial and lifestyle factors. RESULTS: Increases in hot flash severity were associated with late transition stage, early postmenopause, use of HRT, duration of early transition stage, age of entry into early PM and level of FSH. Age of entry into early transition and estrone levels were associated with decreased hot flash severity. Not associated with hot flash severity were being in early transition stage, age of entry into or duration of late transition stage and all of the psychosocial (anxiety, stress, depressed mood) and lifestyle variables (BMI, activity level, sleep, alcohol use). CONCLUSIONS: Variables associated with reproductive aging independently predicted changes in hot flash severity; psychosocial and lifestyle variables did not. The effect of age dropped out when factors associated with reproductive aging were considered. Use of HRT ameliorated but did not eliminate severe hot flashes suggesting that there is room for alternative approaches less likely to cause harm. 相似文献
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Richter WM Rodriguez R Woods KR Axelson PW 《Archives of physical medicine and rehabilitation》2007,88(1):81-87
OBJECTIVES: To investigate the natural stroke patterns of wheelchair users pushing on a level surface, to determine if users adapt their stroke patterns for pushing uphill, and to assess whether there are biomechanic advantages to one or more of the stroke patterns. DESIGN: Case series. SETTING: Biomechanics laboratory. PARTICIPANTS: Twenty-six manual wheelchair users with a spinal cord injury. INTERVENTION: Subjects pushed their own wheelchairs at self-selected speeds on a research treadmill set to level, 3 degrees , and 6 degrees grades. Stroke patterns were measured using a motion capture system. Handrim biomechanics were measured using an instrumented wheel. MAIN OUTCOME MEASURES: Stroke patterns were classified for both level and uphill propulsion according to 1 of 4 common classifications: arcing, semi-circular, single-looping (SLOP), and double-looping (DLOP). Biomechanic outcomes of speed, peak handrim force, cadence, and push angle were all compared across stroke classifications using an analysis of variance. RESULTS: Only 3 of the 4 stroke patterns were observed. None of the subjects used the semi-circular pattern. For level propulsion, the stroke patterns were fairly balanced between arcing (42%), SLOP (31%), and DLOP (27%). Subjects tended to change their stroke pattern for pushing uphill, with 73% of the subjects choosing the arcing pattern by the 6 degrees grade. No statistically significant differences were found in handrim biomechanics or subject characteristics across stroke pattern groups. CONCLUSIONS: Wheelchair users likely adapt their stroke pattern to accommodate their propulsion environment. Based on the large percentage of subjects who adopted the arcing pattern for pushing uphill, there may be benefits to the arcing pattern for pushing uphill. In light of this and other recent work, it is recommended that clinicians not instruct users to utilize a single stroke pattern in their everyday propulsion environments. 相似文献
139.
Woods CD 《Journal of the California Dental Association》2007,35(3):186-191
Managing the "difficult" patient is a challenge all dentists face. This paper describes a psychodynamic model that pictures the dentist-patient relationship as a two-way interaction that involves unconscious processes. The model uses the three ego states: the parent, the adult, and the child, to understand problematic encounters and how to manage them. Using this model has the potential to enhance the therapeutic alliance, decrease malpractice claims, and lessen anxiety for the patient and the dentist. 相似文献
140.
Richter WM Rodriguez R Woods KR Axelson PW 《Archives of physical medicine and rehabilitation》2007,88(1):76-80
OBJECTIVE: To test the hypothesis that pushing on a cross slope leads to increased handrim loading compared with that found on a level surface. DESIGN: Case series. SETTING: Biomechanics laboratory. PARTICIPANTS: Twenty-six manual wheelchair users. INTERVENTION: Subjects pushed their own wheelchairs on a research treadmill set to level, 3 degrees , and 6 degrees cross slopes. Propulsion speed was self-selected for each cross-slope condition. Handrim biomechanics were measured for the downhill wheel, using an instrumented wheelchair wheel and a motion capture system. MAIN OUTCOME MEASURES: Speed, peak kinetics (force, rate of loading, torque), push angle, cadence, push distance, and power output were averaged over a 20-push set for each subject and each cross-slope condition. Outcomes were compared across cross slopes using a repeated-measures analysis of variance. RESULTS: Push angle and cadence were unaffected by cross slope. A trend of decreasing self-selected speeds with increasing cross slope was not significant. There were considerable increases in the peak kinetic measures, with the axial moment increasing by a factor of 1.8 on the 6 degrees cross slope (P=.000). More pushes were required to cover the same distance when on a cross slope (P<.034). The power required for propulsion increased by a factor of 2.3 on the 6 degrees cross slope (P=.000). CONCLUSIONS: Users must push harder when on a cross slope. This increased loading is borne by the users' arms, which are at risk for overuse injuries. Exposure to biomechanic loading can be reduced by avoiding cross slopes when possible. 相似文献