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The application of potent combinations of antiretroviral drugs ('highly active antiretroviral therapy' (HAART)) makes effective therapy of HIV infection feasible. Consequently, the pattern of opportunistic infections and other secondary complications has changed. The incidence of infections and mortality due to aids has declined significantly. Further, the occurrence of other infections and syndromes, till now unknown in patients with aids, has been observed. It is thought that these are caused by HAART-induced inflammation, a phenomenon due to immune enhancement following HAART. An important issue is whether primary and secondary prophylaxis against opportunistic infections can be discontinued after improvement of the immune system: indeed, there are reports that discontinuation is safe in patients with persistent CD4+ cell counts above the critical level for that particular infection while CD4+ cell counts are monitored carefully. 相似文献
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L Ridder F Briganti MG Boersma S Boeren EH Vis A Scozzafava C Veeger IM Rietjens 《Canadian Metallurgical Quarterly》1998,257(1):92-100
Dot-immunoblotting assay (DIA) using five monoclonal antibodies (MAbs) to infectious bronchitis virus (IBV) was used to detect and classify the viruses propagated in embryonated chicken eggs. Using a group-specific MAb 3F5, 10 reference strains and 12 Korean isolates of IBV were successfully detected by DIA, and the lowest virus titer of IBV detected by DIA was approximately less than 10(3.8) mean embryo infective dose/ml. For evaluating the diagnostic efficiency, DIA was compared with the conventional infectious bronchitis (IB) diagnostic method. IBV antigens in allantoic fluid from embryonated eggs inoculated with IB-suspected field samples were specifically detected by DIA within only one or two egg passages, whereas the conventional embryonated egg inoculation method required four to seven egg passages for confirming IBV infection. These results indicated that DIA could significantly reduce time and cost for IB diagnosis. For examining the possibility of classifying IBV by DIA, four strain-specific MAbs, 3A4, 2A3, 6F7, and 2C6, were used. According to the MAb reacting patterns to the IBV antigens, the 10 IBV reference strains were classified into six groups; seven strains belonged to three different groups, and the other three strains each belonged to an individual group. In the case of 12 Korean isolates of IBV, they were classified in six groups. Among the six groups, the MAb reacting patterns of three groups matched those of the IBV reference strains, but the others did not. These data suggest that at least three variant serotypes of IBV exist in Korea. 相似文献
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We have investigated the regulatory role of nitric oxide (NO) in corticotropin-releasing hormone (CRH) release from the human perfused placental lobule in vitro. The effects of the NO donor sodium nitroprusside, the NO synthase inhibitor N omega-nitro-L-arginine, and the NO substrate L-arginine on human (h) placental CRH secretion have been studied. Single lobules of term placentae were bilaterally perfused with Krebs solution (5 mL/min; 95% O2-5% CO2; 37 C; pH 7.3). Fetal and maternal perfusates were collected at 4 C every 30 min for 3 h. CRH immunoreactivity (CRH-IR) in perfusates was measured by RIA using the 41-residue synthetic CRH as standard, 125I-labeled Tyr-hCRH as tracer, and a rabbit anti-CRH antibody Y2BO. The sensitivity of the assay was 0.13 pmol/L. Under basal conditions, human perfused placentae in vitro continuously secreted CRH-IR, which diluted in parallel to a synthetic hCRH-(1-41) standard curve. Size-exclusion chromatography of placental perfusates using a Sephadex G-50 column indicated that placental CRH-IR predominately coeluted with hCRH-(1-41) standard. Basal maternal perfusate CRH-IR levels (27 +/- 4 pmol/L) released from perfused placental lobules were nearly 10-fold greater than fetal perfusate CRH-IR levels (3.4 +/- 0.7 pmol/L; P < 0.05). Infusion of sodium nitroprusside (30-100 mumol/L) into the maternal and fetal placental circulations inhibited CRH-IR release into maternal perfusate in a concentration-dependent manner, but did not inhibit CRH-IR release into the fetal perfusate. N omega-nitro-L-arginine (100 mumol/L) increased placental CRH-IR secretion into fetal perfusate, and this effect was reversed by the infusion of L-arginine (100 mumol/L), which also reduced release below basal levels. In contrast, maternal perfusate CRH-IR levels were not affected by N omega-nitro-L-arginine or L-arginine. These results indicate that the human perfused placenta in vitro releases a substance of similar mol wt and hCRH-IR. Moreover, modulators of the NO signaling pathway differentially affect placental secretion of CRH-IR into the maternal and fetal perfusates. These data are consistent with the involvement of NO in the regulation of placental CRH release during pregnancy. 相似文献
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The necessity is substantiated for use of apiphytoproducts in patients with duodenal ulcer who had become victims of Chernobyl accident. Apiphytoproducts were found out to accelerate the natural elimination of cesium radionuclides from the body, to normalize the indices for lipid peroxidation; they can be used on a monotherapy basis or combined with antisecretory or anti-Helicobacter drug preparations. 相似文献
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IM Rutkow 《Canadian Metallurgical Quarterly》1998,78(6):921-40, v
Such important, yet basic, questions as the percentage chance that an individual will over the course of his or her life be in need of or actually undergo a groin herniorrhaphy or the absolute number and type of hernias that exist in a given society on any particular day continue to be statistically undefined. A review of epidemiologic data provides come preliminary answers. Recent studies from the National Center for Health Statistics show that approximately 750,000 groin herniorrhaphies are completed annually in the United States. More than 80% of these operations involve the use of mesh prosthesis and are performed on an outpatient basis. Despite the large number of hernioplasties completed, the public's understanding of hernias and their management remains unsophisticated. 相似文献
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Exposure to infection information is important for estimating vaccine efficacy, but it is difficult to collect and inherently prone to missingness and mismeasurement. It is, therefore, generally not feasible to collect good exposure information on all participants in a large vaccine trial. We discuss study designs that collect detailed exposure information for only a small subset of trial participants, while collecting crude exposure information on all participants, and treat estimation of vaccine efficacy in the missing data/measurement error framework. We demonstrate with the example of an HIV vaccine trial the improvements in bias and efficiency when we combine the different levels of exposure information to estimate vaccine efficacy for reducing both susceptibility and infectiousness. We compare the performance of recently developed semi-parametric missing data methods of Pepe and Fleming and Carroll and Wand, Robins, Hsieh and Newey, and Reilly and Pepe. 相似文献
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