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Bilharziosis or schistosomiasis is the third leading endemic parasitic disease in the world, following malaria and ambiasis. More than 300 million individuals are infested. Schistomosomes are blood flukes which live in the perivisceral veins. Clinical signs result from ova migrations. Transmitted by urine and feces, the parasite cycle requires intermediary host, usually fresh water snails. Bilharsiosis is endemic in tropical zones where it is a major public health problem closely correlated with the socio-economic conditions. Liver, intestinal or urinary complications, depending on the species, lead to underestimated morbidity and mortality. Pulmonary lesions are attributed to 3 species: S. haematobium, S. mansoni and S. japonicum. Although the lung is mandatory step in the parasite cycle, pulmonary manifestations are limited. They can be acute or chronic depending on the phase of the cycle, but are the most frequent extradigestive localization for S. mansoni. Morbidity due to chronic manifestations is particularly severe and should be prevented whenever possible.  相似文献   
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The objective of this study is to document the use of hormonal therapies in treating prostate cancer in Ontario in the last decade. Drug utilization data were extracted from the Ontario Drug Benefit Program, while surgical orchidectomy rates were calculated from Hospital Medical Records Institute data. The provincial rate of orchidectomy showed a 55% relative increase from 1981 to 1991. There was a 6.4-fold variation in orchidectomy rates among counties in Ontario. As well, the expenditures on new hormonal therapies rose 38-fold between 1985 and 1990, and doubled between 1990 and 1992. There was no consistent relationship between use of orchidectomy and hormonal drug therapy at the county level. We conclude that both forms of hormonal therapy have increased in Ontario. The wide variation in surgical orchidectomy rates observed in Ontario suggests differences in practice styles and possible medical uncertainty. Guidelines for the hormonal therapy of prostate cancer may be a helpful step forward for practitioners and patients.  相似文献   
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Older adults make up an ever-growing proportion of human immunodeficiency virus (HIV) cases in the United States, with approximately 25% of infections occurring in adults over the age of 50 years. Although there is a preliminary body of literature addressing the socioeconomic and prognostic issues of HIV infection in older adults, very little rigorous scientific research has looked at the significant clinical issues relevant to this growing population. Treatment of older adults is complicated by an increased prevalence of medical comorbidities, but little is known about the effects of complicated medication regimens in this group, as they are routinely excluded from clinical trials of newer HIV medications. The delay in diagnosis and treatment of HIV in older adults has led to poorer outcomes, including lower baseline CD4 counts, decreased time to acquired immune deficiency syndrome diagnosis, and increased mortality. Despite these facts, there is mounting evidence that timely diagnosis and treatment of HIV in older adults leads to improved outcomes, similar to younger patients. This review evaluates the literature focusing on HIV and older adults.  相似文献   
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Mast cells release histamine and other mediators of allergy in response to stimulation of their IgE receptors. This release is generally thought to be mediated by an elevation of cytosolic Ca2+. Recent evidence suggests that there might be factors that modulate the coupling between Ca2+ levels and mediator release. The present report identifies adenosine as one such modulator. Adenosine and several of its metabolically stable analogues were shown to enhance histamine release from rat peritoneal mast cells in response to stimuli such as concanavalin A. Metabolizing endogenous adenosine with adenosine deaminase dampened the response to stimuli, whereas trapping endogenous adenosine inside mast cells with nucleoside-transport inhibitors markedly enhanced stimulated histamine release. The metabolically stable adenosine analogue 5'-(N-ethylcarboxamido)adenosine (NECA) did not affect the initial steps in the sequence from IgE-receptor activation to mediator release, which are generation of inositol trisphosphate and increase of cytosolic Ca2+. However, NECA did enhance the release induced in ATP-permeabilized cells by exogenous Ca2+, but it had no effect on the release induced by phorbol esters. These data suggest that adenosine sensitizes mediator release by a mechanism regulating stimulus-secretion coupling at a step distal to receptor activation and second-messenger generation.  相似文献   
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Immunologic Research - Results of the anti-nuclear antibodies-indirect immunofluorescence assay (anti-cell antibodies test) on HEp-2 cell substrates should be communicated to clinicians in a...  相似文献   
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