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991.

Introduction

Awareness and knowledge of treatment as prevention (TasP) was assessed among HIV-positive and HIV-negative gay, bisexual and other men who have sex with men (GBMSM) in Vancouver, Canada.

Methods

Baseline cross-sectional survey data were analyzed for GBMSM enrolled, via respondent-driven sampling (RDS), in the Momentum Health Study. TasP awareness was defined as ever versus never heard of the term “TasP.” Multivariable logistic regression identified covariates of TasP awareness. Among those aware of TasP, men''s level of knowledge of TasP was explored through an examination of self-perceived knowledge levels, risk perceptions and short-answer definitions of TasP which were coded as “complete” if three TasP-related components were identified (i.e. HIV treatment, viral suppression and prevention of transmission). Information source was also assessed. Analyses were stratified by HIV status and RDS adjusted.

Results

Of 719 participants, 23% were HIV-positive, 68% Caucasian and median age was 33 (Interquartile range (IQR) 26,47). Overall, 46% heard of TasP with differences by HIV status [69% HIV-positive vs. 41% HIV-negative GBMSM (p<0.0001)]. In adjusted models: HIV-positive GBMSM were more likely to have heard of TasP if they were Canadian born, unemployed, not using party drugs and had higher CD4 counts; HIV-negative GBMSM were more likely to have heard of TasP if they were Caucasian (vs. Aboriginal), students, had higher education, a regular partner and multiple sexual partners. Among those aware of TasP 91% of HIV-positive and 69% of HIV-negative GBMSM (p<0.0001) felt they knew “a lot” or “a bit in general” about TasP; 64 and 41% (p=0.002) felt HIV treatment made the risk of transmission “a lot lower”; and 21 and 13% (p<0.0001) demonstrated “complete” TasP definitions. The leading information source was doctors (44%) for HIV-positive GBMSM and community agencies (38%) for HIV-negative GBMSM, followed by gay media for both populations (34%).

Conclusions

Nearly half of GBMSM in this study reported having heard of TasP, yet only 14% demonstrated complete understanding of the concept. Variations in TasP awareness and knowledge by HIV status, and key socio-demographic, behavioural and clinical factors, highlight a need for health communication strategies relevant to diverse communities of GBMSM in order to advance overall TasP health literacy.  相似文献   
992.
993.
Dairy production in the United States is moving towards large-herd milking operations, resulting in an increase in task specialization and work demands. The objective of this project was to provide preliminary evidence of the association of a number of specific job conditions that commonly characterize large-herd parlor milking operations with work-related musculoskeletal symptoms (MSS). A modified version of the Standardized Nordic Questionnaire was administered to assess MSS prevalence among 450 US large-herd parlor workers. Worker demographics and MSS prevalences were generated. Prevalence ratios were also generated to determine associations of a number of specific job conditions that commonly characterize large-herd parlor milking operations with work-related MSS. Work-related MSS are prevalent among large-herd parlor workers, since nearly 80% report 12-month prevalences of one or more symptoms, which are primarily located in the upper extremities, specifically shoulders and wrist/hand. Specific large-herd milking parlor job conditions are associated with MSS in multiple body regions, including performing the same task repeatedly, insufficient rest breaks, working when injured, static postures, adverse environmental conditions, and reaching overhead. These findings support the need for administrative and engineering solutions aimed at reducing exposure to job risk factors for work-related MSS among large-herd parlor workers.  相似文献   
994.
抗肿瘤药——多西他赛   总被引:6,自引:0,他引:6       下载免费PDF全文
多西他赛(Docetaxel、泰索帝)是一种新型抗肿瘤药物,它属于紫杉类化合物,为白色或近似白色粉状物,相对分子量8079。结构式如下:1药效学本品的作用机制是加强微管蛋白聚合作用和抑制微管解聚作用,导致形成稳定的非功能性微管束,因而破坏肿瘤细胞的...  相似文献   
995.
Balloon dilation catheters were used to treat 94 gastrointestinal strictures in 92 patients over a 6-year period. Long-term follow-up data were obtained for 80 of these patients, with a mean follow-up period of 389 days. Overall, of the patients who underwent a successful dilation procedure, 83% remained symptom free after 1 year, and 69% after 2 years. The location of the stricture did not significantly influence the long-term outcome, nor did procedure characteristics, aside from primary technical failure. Both patients with malignant strictures and those whose strictures were associated with an anastomosis were more likely than other patients to have recurrent symptoms.  相似文献   
996.
997.
Clinical studies suggest that agonists at peroxisome proliferator-activated receptor gamma (PPARγ) may exert beneficial effects in patients with mild-to-moderate Alzheimer''s disease (AD), but the mechanism for the potential therapeutic interest of this class of drugs has not yet been elucidated. Here, in mice overexpressing mutant human amyloid precursor protein, we found that chronic treatment with rosiglitazone, a high-affinity agonist at PPARγ, facilitated β-amyloid peptide (Aβ) clearance. Rosiglitazone not only reduced Aβ burden in the brain but, importantly, almost completely removed the abundant amyloid plaques observed in the hippocampus and entorhinal cortex of 13-month-old transgenic mice. In the hippocampus, neuropil threads containing phosphorylated tau, probably corresponding to dystrophic neurites, were also decreased by the drug. Rosiglitazone switched on the activated microglial phenotype, promoting its phagocytic ability, reducing the expression of proinflammatory markers and inducing factors for alternative differentiation. The decreased amyloid pathology may account for the reduction of p-tau-containing neuropil threads and for the rescue of impaired recognition and spatial memory in the transgenic mice. This study provides further insights into the mechanisms for the beneficial effect of rosiglitazone in AD patients.  相似文献   
998.
The distribution of intermediate filaments (vimentin, cytokeratins, desmin) and microfilaments (alpha-smooth muscle actin and muscle specific actin) was studied immunohistochemically in bovine ovaries, with and without cystic ovarian disease. The immunohistochemically stained area (IHCSA), was quantified by image analysis, to evaluate the expression of these cytoskeletal proteins in the follicular wall of healthy antral, atretic, and cystic follicles. The granulosa cell layer of cystic follicles and atretic follicles had a significantly larger IHCSA for vimentin than did healthy antral follicles. Cytokeratins reacted lightly in the granulosa cells of antral follicles of normal ovaries, whereas granulosa cells of atretic and cystic follicles showed significantly higher IHCSA values. Immunohistochemical localization of desmin, muscle specific actin, and alpha-smooth muscle actin was restricted to the theca externa. This study supports earlier suggestions that strongly positive reactions with vimentin and cytokeratin antibodies observed in the granulosa cells of cystic follicles are due to the reorganization that occurs in the follicle during the process of cystic development, and are associated with changes in the expression of cytoskeletal proteins that are essential to proper cellular functioning.  相似文献   
999.
BACKGROUND: In Castilla-La Mancha, Spain, the area with the highest density of vineyards in the world, 2 cases of Vitis vinifera pollen allergy have been previously reported. OBJECTIVE: To determine the clinical relevance and biochemical characteristics of vine pollen in the Spanish province of Ciudad Real. METHODS: We designed a prospective study of patients treated in the allergy units from Puertollano and Ciudad Real for respiratory symptoms of 4 months' duration in the year 2000. Skin prick tests with a standard aeroallergen battery and V vinifera pollen extract were performed on all patients. We also performed conjunctival and bronchial provocation tests and serum specific IgE and sodium dodecyl sulfate-polyacrylamide gel electrophoresis immunoblotting on the patients who tested positive for V vinifera pollen. RESULTS: We included 200 patients, 98 sensitized to any pollen and 9 to V vinifera pollen. We found 8 of 9 positive conjunctival provocation test results and a positive bronchial provocation result to vine pollen in a vine grower. Serum specific IgE against V vinifera pollen was detected in 9 of 9 patients. Immunoblotting with V vinifera pollen extract showed IgE-binding bands at 45 and 67 kDa. CONCLUSIONS: Vine pollen could be the cause of pollinosis in exposed patients living in areas with a high density of vineyards.  相似文献   
1000.
The etiological diagnosis of prosthetic joint infection (PJI) requires the isolation of microorganisms from periprosthetic samples. Microbiological cultures often yield false-positive and false-negative results. 16S rRNA gene PCR combined with sequencing (16SPCR) has proven useful for diagnosing various infections. We performed a prospective study to compare the utility of this approach with that of culture to diagnose PJI using intraoperative periprosthetic samples. We analyzed 176 samples from 40 patients with PJI and 321 samples from 82 noninfected patients using conventional culture and 16SPCR. Three statistical studies were undertaken following a previously validated mathematical model: sample-to-sample analysis, calculation of the number of samples to be studied, and calculation of the number of positive samples necessary to diagnose PJI. When only the number of positive samples is taken into consideration, a 16SPCR-positive result in one sample has good specificity and positive predictive value for PJI (specificity, 96.3%; positive predictive value, 91.7%; and likelihood ratio [LR], 22), while 3 positive cultures with the same microorganism are necessary to achieve similar specificity. The best combination of results for 16SPCR was observed when 5 samples were studied and the same microorganism was detected in 2 of them (sensitivity, 94%; specificity, 100%; and LR, 69.62). The results for 5 samples with 2 positive cultures were 96% and 82%, respectively, and the likelihood ratio was 1.06. 16SPCR is more specific and has a better positive predictive value than culture for diagnosis of PJI. A positive 16SPCR result is largely suggestive of PJI, even when few samples are analyzed; however, culture is generally more sensitive.  相似文献   
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