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OBJECTIVE: To determine the frequency of characteristics associated with unprotected heterosexual intercourse in HIV infected adults in an urban area. DESIGN: Retrospective comparison of sexual risk transmission behaviour between HIV infected men and women from a drug treatment site and between women from the drug site and HIV infected women from an urban medical centre. METHODS: HIV infected women and men were asked questions on sexual behaviour for a 1 year period before enrollment. The outcome variable was heterosexual risk behaviour (HRB) defined as having vaginal sex at least once in the previous year and not always using condoms. RESULTS: 73% of the drug clinic females, 72% of the drug clinic males, and 42% of the medical centre female engaged in HRB. Using logistic regression analysis, women and men in drug treatment engaged in similar rates of HRB; however, women in drug treatment were four times (95% CI = 2.0-8.3) more likely to engage in HRB risk behaviour than women from the medical centre. CONCLUSION: The data suggest that a surprisingly large portion of HIV infected patients under treatment engaged in HRB, especially former drug users. Without specifically targeted interventions, the heterosexual spread of HIV in urban areas will continue to be a serious problem. 相似文献
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WT Sholl 《Canadian Metallurgical Quarterly》1997,182(11):407-408
Following the fiftieth anniversary of the National Health Service Act 1946, I make the case in this article that professional provision of health care must remain the property of the citizen under common law and must not become a commodity that is bought and sold by third parties, including the state. 相似文献
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Nonlinear sorption of three alcohol ethoxylates to marine sediment: a combined Langmuir and linear sorption process? 总被引:1,自引:0,他引:1
Alcohol ethoxylates (AE) are nonionic surfactants mainly used in laundry cleaning products. The relation between particle bound and freely dissolved concentrations is an important entity in risk assessment. The mechanistic understanding of AE sorption is still poor, hampering extrapolations from laboratory studies to the field. We studied the sorption of three AE with 8 EO units but with increasing alkyl chains (C10, C12, and C14) to a marine sediment. Solid-phase microextraction, using polyacrylate as the extraction phase, was applied to measure freely dissolved concentrations in pore water. A model that combines a Langmuir and a linear sorption term fitted the nonlinear sorption data to sediment well. At low aqueous concentrations, adsorption dominates over absorption leading to higher distribution coefficients for AE at low field concentrations. This dual-mode model offers the possibility to extrapolate to other AE homologues and other marine sediments and also from high to low field concentrations. 相似文献
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BI Reiner EL Siegel KJ French RS Dentry WT Mazan MJ Maroney 《Canadian Metallurgical Quarterly》1997,17(6):1487-1495
The authors demonstrate the use of radiography in the investigation of an historic painting and describe the potential benefits of computed radiography compared with conventional screen-film radiography. The subject for the comparison was a 16 x 19-foot oil-on-canvas painting, Scipio Africanus Freeing Massiva, by Giovanni Battista Tiepolo. Radiographs of the painting were obtained by using a portable, industrial radiographic unit and both conventional screen-film and photostimulable phosphor plate cassettes. For this investigation, computed radiography had a number of advantages over screen-film radiography, largely due to its wider dynamic range and its capabilities for enhancing the digital images with image processing tools such as magnification, edge enhancement, colorization, and airbrushing. The ability to electronically combine images from the large painting into a single composite image file was extremely valuable, as this technique was much less cumbersome and resulted in much higher quality composite images than could be achieved with conventional radiography. An additional advantage of computed radiography includes the capability to easily archive and transmit these images in a digital format for subsequent review. 相似文献
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Rabbits were injected intravenously with 10 to 100 ng of staphylococcal enterotoxin A (SEA) per kg, and colonic temperatures were monitored. The febrile responses were compared with circulating levels of interferon (IFN), tumor necrosis factor (TNF), interleukin-1 (IL-1), IL-2, and IL-6 just before the injection of SEA. Both colonic temperatures and circulating levels of IFN, TNF, and IL-2 started to rise at 1 to 2 h and reached their peak levels at 3 to 5 h after SEA injection. Both the fever and the increased circulating levels of IFN, TNF, and IL-2 produced by SEA were decreased by pretreatment with indomethacin (a cyclo-oxygenase inhibitor) (15 mg/kg, intraperitoneally), anisomycin (a protein synthesis inhibitor) (15 mg/kg, subcutaneously), or dexamethasone (an effective anti-inflammatory and immunosuppressive agent) (4 mg/kg, intravenously) in rabbits. Rabbits were injected intravenously with 30 ng of SEA per kg on four consecutive days, and colonic temperatures were monitored. Compared to rabbits that received the single injection of SEA, rabbits that received four consecutive injections of SEA showed a lesser increase in circulating levels of IFN, TNF, and IL-2 as well as colonic temperatures in response to an intravenous dose of SEA (30 ng/kg). The data suggest that the prevention of the febrile response elicited by SEA by indomethacin, anisomycin, or dexamethasone is due to prevention by these compounds of the increase in the circulating levels of IFN, TNF, and IL-2. The pyrogenic hyporesponsiveness to repeated injection of SEA is associated with decreased production of these circulating cytokines. 相似文献