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排序方式: 共有967条查询结果,搜索用时 46 毫秒
1.
Margaret MacDonald Matthew Law John Kaldor Jim Hales Gregory J. Dore 《The International journal on drug policy》2003,14(5-6):353
Objective: To examine the effectiveness of needle and syringe programmes (NSPs) in preventing HIV transmission among injecting drug users (IDUs).Methods: An ecological study design was used to determine change in HIV prevalence among injecting drug users between cities with and without NSPs. Several data sources, such as electronic journal databases, surveillance reports, websites, and index review of relevant journals, were used to identify studies of HIV seroprevalence among IDUs, and presence of NSPs. The rate of change in HIV prevalence was estimated by regression analysis.Results: There were 778 years of data from 99 cities globally included in the analysis. HIV prevalence decreased by 18.6% per annum in cities that introduce NSPs, and increased by 8.1% in cities that had never introduced NSPs (mean difference −24.7% [95% CI: −43.8, 0.5%], P=0.06). The mean difference was –33% when comparison was weighted to one over the variance of the regression estimator (29% decrease in cities with NSPs and 5% increase in cities without NSPs, P<0.001). When analysis was restricted to cities with first HIV seroprevalence less than 10%, the average annual change in seroprevalence was 18% lower in cities with NSPs (P=0.03).Conclusions: Despite the inherent limitations within an ecological study design, the study provides additional evidence that NSPs reduce transmission of HIV infection. The rapid spread of HIV among IDU populations and increasing rates of injecting in many countries calls for scaling up of NSPs as well as other harm reduction strategies. 相似文献
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T. Diemer D. Buchanan Hales T. Diemer M. Ludwig Petra Huwe W. Weidner 《Reproduktionsmedizin》2000,16(2):155-167
Urogenital infections are established as hazards to male fertility. Various pathophysiological hypotheses have evolved from experimental and clinical studies, facilitating explanation of the effects of bacteria and immunological events on reproductive tissues. Numerous current studies have identified and evaluated infectious mediators accounting for specific molecular events in urogenital infections. Valuable studies can be expected to appear in the future due to improvements in diagnostic procedures and new classifications of urogenital infections. 相似文献
4.
Cyclophosphamide in the seminal fluid of treated males: transmission to females by mating and effect on pregnancy outcome 总被引:2,自引:0,他引:2
Cyclophosphamide is an anticancer and immunosuppressant drug administered to men of reproductive age. In the present study the ability of cyclophosphamide and/or its metabolites to enter secretions of the male reproductive tract, to be transmitted to the female partner upon mating, and to alter progeny outcome was assessed. [14C]Cyclophosphamide was given intravenously to adult male Sprague-Dawley rats; radiolabel (greater than 96% cyclophosphamide) was first found in seminal vesicle fluid within 10 min and equilibrated with plasma radioactivity within 30 min. Furthermore, radiolabel from cyclophosphamide given to the male was transmitted to the female upon mating up to 5 hr post-drug treatment. To study possible consequences of paternal treatment with cyclophosphamide on pregnancy outcome, male rats were administered a single dose of cyclophosphamide, 10, 30, or 100 mg/kg, or saline immediately prior to cohabitation with females in proestrus. There was no effect on the number of pregnant females per sperm-positive females but there was a significant decrease in the number of implantations per pregnant female per male and in the number of live fetuses per pregnant female per male. There was a twofold increase in preimplantation loss. There was no increase in postimplantation loss or number of abnormal fetuses. These results demonstrate that cyclophosphamide not only penetrates the male reproductive tract but that it can be transmitted to the female partner and can affect progeny outcome. 相似文献
5.
D A Quinn B T Thompson M L Terrin J H Thrall C A Athanasoulis K A McKusick P D Stein C A Hales 《JAMA》1992,268(13):1689-1696
OBJECTIVE. The aim of this study was to compare, in women and men suspected of pulmonary embolism, the frequency, risk factors, diagnosis, and presentation of pulmonary embolism as well as the accuracy of the ventilation/perfusion scan (V/Q scan) as a diagnostic tool. DESIGN. Data were collected during a prospective study (the Prospective Investigation of Pulmonary Embolism Diagnosis) to establish the accuracy of the V/Q scan compared with pulmonary angiograms. SETTING. Six tertiary medical centers in Massachusetts, Michigan, Connecticut, Pennsylvania, and North Carolina. PARTICIPANTS. Patients suspected of pulmonary embolism for whom a request was made for a V/Q scan or pulmonary angiogram (496 women and 406 men). RESULTS. Women 50 years old and under had a decreased frequency of pulmonary embolism compared with men of that age (16% vs 32%), but there was no difference in patients over 50 years old (Breslow-Day test, P less than .01). Risk factors for pulmonary embolism, the usefulness of the V/Q scan, and 1-year mortality were not different for women and men. Estrogen use in women was not associated with an increased frequency of pulmonary embolism, except in women using oral contraceptives who had undergone surgery within 3 months; four of five (80%) had emboli compared with four of 28 (14%) age-matched surgical patients not using estrogens (P less than .01). CONCLUSION. Women 50 years old and under (even young women using oral contraceptives) who were suspected of having pulmonary emboli and were enrolled in the Prospective Investigation of Pulmonary Embolism Diagnosis study had a smaller frequency of pulmonary embolism than men of that age, The risk factors for pulmonary embolism were the same for women and men, except that women using oral contraceptives had an increased risk of pulmonary embolism following surgery. Although the V/Q scan was a useful tool in the preliminary evaluation for pulmonary embolism in these women, a pulmonary angiogram was often needed for accurate diagnosis. 相似文献
6.
P. H. Winocour K. J. Moriarty C. N. Hales J. Adams R. Reeve D. Wynick D. Allison S. R. Bloom D. C. Anderson 《Postgraduate medical journal》1992,68(797):196-200
A 15 year old girl with a family history of type 1 multiple endocrine adenomatosis presented with reversible neurological disturbances, hypoglycaemia and hyperinsulinaemia. Initial radiology was normal, but portal venous sampling suggested an insulinoma in the tail of the pancreas which was removed with conservation of the spleen. Hypoglycaemia persisted despite high doses of diazoxide and intravenous dextrose. A second laparotomy revealed a pancreatic endocrine tumour and sub-total pancreatectomy was performed. Histology revealed islet cell microadenomatosis. Hypoglycaemia persisted despite treatment with somatostatin analogues and 40% intravenous dextrose was required to maintain normoglycaemia. A possible lesion near the splenic hilum on computed tomographic scan was reported as a splenunculus although further peripheral, hepatic and portal venous sampling suggested hepatic or systemic lesions. A positron emission scan and selective visceral angiography suggested a lesion in the left upper quadrant. Acute lactic acidosis, rhabdomyolysis and renal failure supervened. Post mortem revealed the putative ''splenunculus'' to be a residual insulinoma, whilst the splenic vein was thrombosed, accounting in part for discrepant venous sampling data. Hyperinsulinaemia in type 1 multiple endocrine adenomatosis may require more aggressive surgical and hormonal intervention than when dealing with solitary insulinomas. Insulinomas may mimic developmental abnormalities on computed tomographic scanning. 相似文献
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A brief historical review of military psychiatry in the United States Army is presented, focusing on the development of psychiatric treatment of soldiers with acute stress reactions. The authors outline the current roles of the military psychiatrist during peacetime and war, including direct care provider, consultant, and administrator, and discuss the contributions of military psychiatry to the civilian sector in the areas of crisis intervention, community psychiatry, family psychiatry, and substance abuse prevention and treatment. 相似文献
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10.
B. J. Hales I. A. Laing L. J. Pearce L. A. Hazell K. L. Mills K. Y. Chua R. B. Thornton P. Richmond A. W. Musk A. L. James P. N. LeSouëf W. R. Thomas 《Clinical and experimental allergy》2007,37(9):1357-1363
BACKGROUND: There is evidence that the specificity of the IgE binding in allergy tests can vary for different populations. OBJECTIVE: We aimed to examine the allergenic specificity of IgE binding in sera from house dust mite (HDM)-atopic subjects in a tropical Australian Aboriginal community. METHODS: Sera shown to contain IgE antibodies to an HDM extract of Dermatophagoides pteronyssinus were examined for IgE binding to a panel of nine purified HDM allergens from this mite species by quantitative microtitre assays. IgG antibody binding (IgG1 and IgG4) was also measured. RESULTS: The IgE-binding activity in the sera from the Aboriginal community was not directed to the expected major groups 1 and 2 HDM allergens but instead to the group 4 amylase allergen. There was also little IgE binding to the potentially cross-reactive tropomyosin (Der p 10) or arginine kinase (Der p 20) allergens. The IgG4 antibody was rarely detected and limited to the Der p 4 allergen. IgG1 antibody binding was frequently measured to all the allergens regardless of an individual's atopic status, whereas in urban communities it is restricted to the major allergens and to atopic subjects. CONCLUSION: The high IgE anti-HDM response of Australian Aboriginals predominantly bound Der p 4 and not the Der p 1 and 2 allergens, showing a distinctive allergy that could affect the disease outcome and diagnosis. 相似文献