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Serosorting (i.e., engaging in unprotected sex with partners known to be of the same serostatus) can be a difficult process for men who have sex with men (MSM) who frequently make assumptions about their partners' serostatus. This process can be further complicated by a partner's dishonesty as well as other individual and contextual factors. The present study specifically examined how assumptions of serostatus made about unknown serostatus partners impact on the sexual behavior of 110 alcohol-abusing HIV-positive MSM. Although previous research has shown that HIV-positive MSM are more likely to serosort with other known HIV-positive men than with known HIV-negative men, our data suggest that unprotected sex behavior may not be specifically driven by whether or not they made assumptions of seroconcordance or serodiscordance. The types of assumptions these HIV-positive MSM made about their unknown status sexual partners and the basis for such assumptions were also examined. Owing to the ambiguities involved in assumptions of a partner's serostatus in sexual encounters, the 'unknown status' partner category is analytically distinct from 'known status' categories, and needs to be more fully explored because of its impact on perceived serosorting, rather than actual serosorting, among HIV-positive men.  相似文献   
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BACKGROUND: Based on good results in the treatment of superficial skin tumours, since the early 1990s topical photodynamic therapy with aminolaevulinic acid (ALA PDT) has been used for disseminated, inflammatory dermatoses including psoriasis. However, there is still a lack of well-documented trials. OBJECTIVE: A prospective randomized, double-blind phase I/II intrapatient comparison study was conducted in 12 patients to investigate whether topical ALA PDT is an effective treatment for chronic plaque-type psoriasis. METHODS: In each patient three psoriatic plaques were randomly treated with a light dose of 20 J/cm(2) and 0.1%, 1% and 5% ALA, respectively. Treatment was conducted twice a week until complete clearance or for a maximum of 12 irradiations. Therapeutic efficacy was assessed by weekly determination of the psoriasis severity index (PSI). RESULTS: The mean percentage improvement was 37.5%, 45.6% and 51.2% in the 0.1%, 1% and 5% ALA-treated groups, respectively. Irradiation had to be interrupted several times because of severe burning and pain sensation. CONCLUSION: Topical ALA PDT did not prove to be an appropriate treatment option for plaque-type psoriasis due to disappointing clinical efficacy, the time-consuming treatment procedure and its unfavourable adverse event profile.  相似文献   
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The Video Display Terminal Eye Clinic was designed to relieve the symptoms of video display terminal users by diagnosing and treating visual problems and by analyzing the patients' work station environment through an in-office simulation and making suggestions for improvements. The Clinic was open to the public and patients were therefore self-selected. The symptoms, diagnoses, and treatments were compiled retrospectively and reported for 153 patients. Vision problems were diagnosed in most patients. The most frequent diagnoses included: presbyopia, improper spectacle design for presbyopia, accomodative deficiencies, esophoria, exophoria, and hyperopia. The results suggest that proper visual care and work station arrangement can improve comfort.  相似文献   
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Cancer of the maxillary sinus treated with surgery and/or radiation therapy   总被引:1,自引:0,他引:1  
This is an analysis of 37 previously untreated patients with squamous cell carcinoma of the maxillary sinus treated with curative intent at the University of Florida from January 1966 through January 1984. All patients were followed for at least two years and 86 per cent (32/27) were followed for a minimum of five years. Patients were treated for cure with radiation therapy alone (25), surgery alone (1), or surgery and preoperative (6) or postoperative (5) radiation therapy. This study presents the results of treatment and the incidence of treatment-related complications in this group of patients.  相似文献   
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Pregnancies after in vitro fertilization and transfer of human blastocysts   总被引:10,自引:0,他引:10  
In a study of 29 cycles of IVF, ET was performed on day 5 after oocyte recovery when embryos had developed to the morula/blastocyst stage. Three preclinical pregnancies and three live births resulted (2 singleton and 1 twin), giving a viable PR per ET of 10%. It is concluded that while day 5 ET may well be important in terms of embryo biopsy for the preimplantation diagnosis of genetic disease, day 2 ET remains preferable for therapeutic IVF. Although these data would not support the introduction of day 5 ET into routine therapeutic IVF, delayed ET should be considered as an alternative approach to preimplantation diagnosis. Indeed, because the latter will generally involve the treatment of normal, fertile couples, it might be predicted that embryo survival rates, and thus the rate of pregnancy after day 5 ET, would be better than those presented here.  相似文献   
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