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61.
Little is known about the background of commercial sex workers in Africa. This study investigated how women in a trading town on the trans-Africa highway in southwest Uganda become involved in commercial sex work, which factors contribute to their economic success or lack of success, and what effect life trajectories and economic success have on negotiating power and risk behaviour. Over the course of two years detailed life histories of 34 women were collected through recording open, in-depth interviews, the collection of sexual and income and expenditure diaries, visits to the women's native villages, and participant observation. The women share similar disadvantaged backgrounds and this has played a role in their move into commercial sex. They have divergent experiences, however, in their utilisation of opportunities and in the level of success they achieve. They have developed different life styles and a variety of ways of dealing with sexual relationships. Three groups of women were identified: (1) women who work in the back-street bars, have no capital of their own and are almost entirely dependent on selling sex for their livelihood; (2) waitresses in the bars along the main road who engage in a more institutionalised kind of commercial sex, often mediated by middlemen and (3) the more successful entrepreneurs who earn money from their own bars as well as from commercial sex. The three groups had different risk profiles. Due partly to their financial independence from men, women in the latter group have taken control of sexual relationships and can negotiate good sexual deals for themselves, both financially and in terms of safe sex. The poorer women were more vulnerable and less able to negotiate safer sex. A disadvantaged background and restricted access to economic resources are the major reasons for women gravitating to commercial sex work. Various aspects of personality play a role in utilising income from commercial sex to set up an economic basis that then makes the selling of sex unnecessary. This has implications for interventions, and part of the longer-term solution should lie in improving the economic position of women vis-à-vis men. 相似文献
62.
Verdijk RM Mutis T Wilke M Pool J Schrama E Brand A Goulmy E 《The hematology journal : the official journal of the European Haematology Association / EHA》2002,3(6):271-275
Tissue expression of minor Histocompatibility antigens HA-1 and HA-2 is limited to the hematopoietic system. Therefore, ex vivo generated HA-1/HA-2 specific cytotoxic T lymphocytes (CTLs) can be applied for adoptive immunotherapy of relapsed leukemia after HLA-matched HA-1/HA-2 mismatched stem cell transplantation. Here we used T cell receptor beta variable chain (TCRBV) spectratyping and/or TCRBV sequencing to monitor the specific TCR usage in eleven HA-1/HA-2 CTLs that were induced ex vivo with peptide pulsed dendritic cells. The HA-2 induced CTLs used different TCRBV. In contrast, the development of HA-1 specific CTLs coincided with prominent skewing of TCRBV7 spectratypes. Sequencing of the TCRBV7 specific PCR products used by these ex vivo generated HA-1 CTLs revealed the exclusive usage of TCRBV7-9*03, identical to the TCRBV used by HA-1 specific CTLs induced in vivo after stem cell transplantation. Thus, monitoring of immunotherapy with HA-1 specific CTLs is now also feasible by TCRBV spectratyping. 相似文献
63.
The US Vaccine Adverse Event Reporting System (VAERS), which is charged with vigilance for detecting vaccine-related safety issues, faces an increasingly complex immunisation environment. Since 1990, steady increases in vaccine licensing and distribution have resulted in increasing numbers of reports to VAERS. Prominent features of current reports include more routine vaccine co-administration and frequent reports of new postvaccination clinical syndromes. Data-mining methods, based on disproportionality analyses, are one strategy being pursued by VAERS researchers to increase the utility of its complex database. The types of analyses used include proportional reporting ratios, association rule discovery, and various 'historic limits' methods that compare observed versus expected event counts. The use of such strategies in VAERS has been primarily supplemental and retrospective. Signals for inactivated influenza, typhoid and tetanus toxoid-containing vaccines have been successfully identified. Concerns flagged through data mining should always be subject to clinical case review as a first evaluation step. Persistent issues should be subject to formal hypothesis testing in large linked databases or other controlled-study settings. Automated data-mining techniques for prospective use are currently undergoing development and evaluation within VAERS. Their use (as one signal-detection tool among many) by trained medical evaluators who are aware of system limitations is one legitimate approach to improving the ability of VAERS to generate vaccine-safety hypotheses. Such approaches are needed as more new vaccines continue to be licensed. 相似文献
64.
Hamm PB Nicogossian AE Pool SL Wear ML Billica RD 《Aviation, space, and environmental medicine》2000,71(6):564-570
BACKGROUND: Information has been collected regarding the immediate physiological effects of spaceflight on humans. However, little is yet known regarding long-term effects. The purpose of this paper is to describe the Longitudinal Study of Astronaut Health (LSAH) and report current mortality data. METHODS: All astronauts selected for the United States Space Program are followed from selection throughout their lifetime or until the end of the study. Comparisons are ground-based Johnson Space Center (JSC) employees matched to the astronauts at a 3:1 ratio by sex-specific age and body mass index. They are followed in the same manner as astronauts. Morbidity and mortality data are obtained from medical records supplemented with study questionnaires. Checks for death certificates are made to ascertain death of participants who miss routine examinations. RESULTS: Current cause-specific mortality rates for astronauts selected from 1959 through 1991 are not statistically different from rates for comparison participants for cardiovascular (p = 0.8112), cancer (p = 0.2382), or other disease (p = 0.5040) mortality. Astronauts have a significantly higher mortality rate due to accidents and injuries (p < 0.0001). CONCLUSIONS: Astronauts have a similar risk of death due to chronic diseases as ground-based participants, but are at greater risk for occupational-related accidental death. 相似文献
65.
66.
Sharola Dharmaraj Ban P. Leroy Melanie M. Sohocki Robert K. Koenekoop Isabelle Perrault Khalid Anwar Shagufta Khaliq R. Summathi Devi David G. Birch Elaine De Pool Natalio Izquierdo Lionel Van Maldergem Mohammad Ismail Annette M. Payne Graham E. Holder Shomi S. Bhattacharya Alan C. Bird Josseline Kaplan Irene H. Maumenee 刘欣怡 《美国医学会眼科杂志(中文版)》2005,17(2):119-120
目的:叙述26例先证者中芳香族羟基碳氢化合物受体蛋白样1蛋白质(AIPL1)突变的先天性Leber黑蒙(LCA)的表现型,并比较其他LCA相关性基因的表现型。叙述杂合子携带者的视网膜电图(ERG)。 相似文献
67.
Innervation of supporting cells in the apical turns of the guinea pig cochlea is from type II afferent fibers 总被引:3,自引:0,他引:3
Fechner FP Nadol JB JR Burgess BJ Brown MC 《The Journal of comparative neurology》2001,429(2):289-298
The outer supporting cells in the apical turns of the guinea pig cochlea receive a dense innervation. Our previous study (Fechner et al. [1998] J. Comp. Neurol. 400:299-300) suggested that this innervation of the Deiters' and Hensen's supporting cells was not derived from efferent fibers of the olivocochlear bundle, but its origin has not been further specified. To test the hypothesis that the innervation was afferent in origin, we traced apical afferent fibers that were retrogradely labeled by extracellular injections of horseradish peroxidase. Labeled afferent fibers were of two types: type I fibers contacted inner hair cells, whereas type II fibers crossed the tunnel and contacted outer hair cells. Significantly, most of the type II fibers also formed branches to the outer supporting cells. Although a few olivocochlear efferent fibers formed such branches, counts indicated that the overwhelming majority of the branches were produced by type II afferent fibers. These branches were not produced by basal type II fibers. Apical type II fibers also differed from basal fibers by having shorter lengths, spiraling both apically and basally, and contacting all three rows of outer hair cells. These innervation differences suggest differences in the ways that information from outer hair cells is processed in the apex versus the base of the cochlea. 相似文献
68.
Over the past decade there has been a resurgence of interest in the culture media used in clinical in vitro fertilization. Unfortunately, during this time more confusion than consensus appears to have developed regarding the composition of these media. In order to facilitate a clearer understanding of this field, it is important to understand the role of specific medium components and how their use is regulated by the embryo. The roles of the key nutrients glucose, pyruvate, lactate, and amino acids during the preimplantation period have therefore been presented. Analysis of how the embryo regulates the utilization of such nutrients has led to a clearer understanding of the embryo's requirements during the dynamic period of preimplantation development. From such information, sequential culture media have been developed along with novel noninvasive tests of embryonic viability. It is proposed that continued studies on the human embryo will lead to further improvements in embryo culture conditions and the optimization of viability assays, culminating in the ability to transfer single embryos for the majority of, if not all patients. 相似文献
69.
70.
ABSTRACT We report an unusual case of bilateral chronic conjunctivitis and corneal scarring in a boy with X-linked hypogammaglobulinaemia (XLH) who did not respond to the usual antibacterial and antiviral therapy. An immunofluorescence test for Chlamydia trachomatis from an eye swab was strongly positive. Within days of commencement of local and systemic tetracycline therapy, he showed marked improvement. Since conjunctival follicle formation, which depends on the presence of a B-cell population, may not occur in XLH, clinical examination in chlamydia conjunctivitis may be misleading and lead to a delay in diagnosis and treatment with resulting corneal complications, unless laboratory evidence of chlamydia infection is specifically sought. 相似文献