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Positive, negative, unknown: assumptions of HIV status among HIV-positive men who have sex with men.
Jeffrey T Parsons Joseph Severino Jose Nanin Joseph C Punzalan Kirk von Sternberg Whitney Missildine David Frost 《AIDS education and prevention》2006,18(2):139-149
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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The relationship between price of services, quality of care, and patient time costs for general dental practice. 下载免费PDF全文
OBJECTIVE: To examine the relationships between price of services, quality of care, and patient time costs in private practices of general dentists. DATA SOURCE/STUDY SETTING: In October 1992, a 3.7 percent sample of eligible general dentists in part-time or full-time private practice in 1991 was randomly drawn from a sampling frame tailored from data gathered by the 1991-1992 American Dental Association Distribution of Dentists census of all United States dentists. DATA COLLECTION: A mail survey was used to collect data on dentist demographic characteristics, dental practice characteristics practice finances, and insurance. The survey was completed and returned by 3,048 general dentists (77 percent response rate). Local area population characteristics were obtained from secondary sources. STUDY DESIGN: Two-stage least squares regression was used to evaluate the structural relationships between price of services, quality of care, and time costs to patients. Structural equations were estimated for four different quality of care measures and two time costs. PRINCIPAL FINDINGS: Price of services and quality of care were significantly related to each other. Higher quality of care was associated with higher price of services and, reciprocally, higher price of services was associated with higher quality of care. Shorter waits for a new patient appointment were associated with higher prices. Higher price of services, lower quality of care, and longer waits for a new patient appointment were related to shorter in-office waiting time. CONCLUSIONS: The implication of these findings is that if price of services is constrained, then the quality of care provided by the dentist may also be reduced. 相似文献
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Synergistic interactions between cytokines, chemokines and adhesion molecules may facilitate the selective recruitment of eosinophils into sites of allergic inflammation. Ovalbumin-sensitized IL5TG mice responded to antigen challenge with robust airway eosinophilia 24 and 72 hr post-exposure. Adhesion molecule expression and functional responsiveness of immune cells derived from IL5TG mice to various inflammatory mediators were evaluated. IL5TG-derived eosinophils, but not neutrophils, expressed higher levels of CD49d and CD11b relative to WT. Functional responsiveness to eotaxin was increased in IL5TG eosinophils as demonstrated by a 10× increase in its potency in producing actin polymerization and 3× increase in CD11b upregulation relative to WT. These data are consistent with increased CCR3 expression on IL5TG eosinophils. Responsiveness of eosinophils to LTB4 or MIP-1 was similar between WT and IL-5TG mice. These data provide evidence of synergy between eosinophil-specific cytokines and chemokines that may promote accumulation of this cell type under conditions of allergic inflammation in vivo. 相似文献
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Recurrent Bacteremia Caused by a “Flexispira”-Like Organism in a Patient with X-Linked (Bruton’s) Agammaglobulinemia 下载免费PDF全文
Susan Weir Brenda Cuccherini Anne M. Whitney Marsha L. Ray John P. MacGregor Arnold Steigerwalt Maryam I. Daneshvar Robbin Weyant Betty Wray John Steele Warren Strober Vee J. Gill 《Journal of clinical microbiology》1999,37(8):2439-2445
Helicobacter spp., except for Helicobacter cinaedi, have only rarely been reported in cases of septicemia. A patient with X-linked (Bruton's) agammaglobulinemia was found to have persistent sepsis with a Helicobacter-like organism despite multiple courses of antibiotics. His periods of sepsis were associated with leg swelling thought to be consistent with cellulitis. The organism was fastidious and required a microaerophilic environment containing H(2) for growth. Optimal growth was observed at 35 to 37 degrees C on sheep blood, CDC anaerobe, and Bordet-Gengou agars. Serial subcultures every 4 to 5 days were required to maintain viability. The organism was strongly urease positive and showed highest relatedness to Helicobacter-like organisms with the vernacular name "Flexispira rappini" by 16S rRNA gene sequence analysis. Genomic DNA hybridization studies, however, found 24 to 37% relatedness to "F. rappini" and even less to other Helicobacter spp. Although the organism phenotypically resembles "Flexispira" and Helicobacter, it is thought to represent a new taxon. The patient's infection was eventually cleared with a prolonged (5-month) course of intravenous imipenem and gentamicin. 相似文献