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BACKGROUND AND OBJECTIVES: An eight-member group consisting of Canadian infectious disease and immunology specialists and a family physician with significant experience in HIV management was convened to update existing recommendations, specifically intended for use by Canadian HIV-treating physicians, on the appropriate use of enfuvirtide in HIV/AIDS patients with resistance to other antiretroviral drugs. METHODS: Evidence from the literature and expert opinions of the group members formed the basis of the guidelines. Comments on the draft guidelines were obtained from other physicians across Canada with HIV expertise. The final guidelines represent the group's consensus agreement. RESULTS AND CONCLUSIONS: The recommendations were developed to guide physicians in optimal practices in patient selection for enfuvirtide treatment and subsequent patient management. The issues considered include positive predictors of response to enfuvirtide, stage of disease, optimization of the background regimen, early indicators of enfuvirtide response, and patient education and support.  相似文献   
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The significance of life stress, coping, and social support was examined in relation to depressive symptomatology in a sample of 160 asymptomatic and mildly symptomatic HIV-antibody-positive (HIV+) men. The participants (mean age = 32 years) were interviewed about the life stress that they had experienced in the previous 6  相似文献   
95.
Risk Factors for a First Febrile Seizure: A Matched Case-Control Study   总被引:10,自引:6,他引:4  
Summary We conducted a matched casecontrol study to identify risk factors for first febrile seizures, with special emphasis on characteristics of the acute illness episode. Cases were identified through hospital emergency departments; controls were identified through outpatient clinics and emergency departments. Sixtynine children with first febrile seizures and no history of previous unprovoked seizures were matched for age (±6 months), site of routine pediatric care, and date of visit (±weeks) with 1 or 2 febrile controls who had no history of previous febrile or unprovoked seizures. Medical records for the index visit were reviewed, and parents were interviewed by telephone. Illness characteristics examined included height of temperature, type of underlying illness, contact with a physician during the illness but before the index visit, and use of acetaminophen or decongestants. Family history of febrile and of unprovoked seizures, sociodemographic characteristics, daycare use, and selected preand perinatal variables were also studied. On multivariable analysis, significant independent risk factors were height of temperature, history of febrile seizures in a firstor in a higher degree relative. Gastroenteritis as the underlying illness had a significant inverse (i.e., protective) association with febrile seizures. Maternal smoking during pregnancy was a marginally significant predictor of febrile seizures.  相似文献   
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PURPOSETo demonstrate the spectrum of CT and MR imaging findings in patients with Wegener granulomatosis and to determine how often these findings could be attributed to either direct extension from paranasal or orbital disease sites, remote granulomas, or central nervous system (CNS) vasculitis.METHODSWe retrospectively reviewed the CT or MR studies of 15 patients with Wegener granulomatosis.RESULTSAbnormal findings were seen in 7 patients (5 examined with MR imaging, 2 with CT). Findings included dural thickening and contrast enhancement (3 patients), infarcts (2 patients), regions of hyperintense signal on T2-weighted MR images (2 patients), and abnormal MR signal in the brain stem (2 patients). Three patients with imaging findings of dural enhancement and thickening were thought to have remote granulomatous lesions involving the dura. No patients had extension from sites external to the CNS or clinical findings suggestive of CNS vasculitis.CONCLUSIONThe spectrum of CT and MR findings in Wegener granulomatosis includes dural thickening and enhancements cerebral infarction, and MR signal abnormalities in the brain stem and white matter. Presumed remote granulomatous lesions were the most common causes of CNS findings in this study. Complications related to non-CNS disease (eg, hypertension, endocarditis) also appear to have played a role in some patients.  相似文献   
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Anatomical and physiological segregation of neurons into ON (brightening detector) and OFF (darkening detector) channels in the retina and subsequent visual system ensure the high sensitivity required for contrast detection and spatial discrimination. This segregation is finest at the visual axis. Neurochemically, ON and OFF ganglion cells at the visual axis seem to be distinguished by different inhibitory transmitters but not excitatory transmitters. Microiontophoretic studies of inhibitory transmitters on the retinal ganglion cells in kittens and adult cats suggest that this neurochemical distinction is poor in immature ganglion cells at the visual axis. Initially both ON and OFF cells seem to be supplied by GABAergic, glycinergic, and catecholaminergic amacrine cells, but in adults, ON cells remain supplied only by GABAergic amacrines, while OFF cells are supplied by glycinergic amacrines. Postnatal elimination of multiple inputs and strengthening of the appropriate inputs, as seen in the central nervous system, also seem to occur at the retinal neurotransmitter synapses during development.  相似文献   
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We studied the pharmacokinetics of intravenously and orally administered lamivudine at six dose levels ranging from 0.5 to 10 mg/kg of body weight in 52 children with human immunodeficiency virus infection. A two-compartment model with first-order elimination from the central compartment was simultaneously fitted to the serum drug concentration-time data obtained after intravenous and oral administration. The maximal concentration at the end of the 1-h intravenous infusion and the area under the concentration-time curve after oral and intravenous administration increased proportionally with the dose. The mean clearance of lamivudine (± standard deviation) in the children was 0.53 ± 0.19 liter/kg/h (229 ± 77 ml/min/m2 of body surface area), and the mean half-lives at the distribution and elimination phases were 0.23 ± 0.18 and 2.2 ± 2.1 h, respectively. Clearance was age dependent when normalized to body weight but age independent when normalized to body surface area. Lamivudine was rapidly absorbed after oral administration, and 66% ± 25% of the oral dose was absorbed. Serum lamivudine concentrations were maintained above 1 μM for ≥8 h of 24 h on the twice daily oral dosing schedule with doses of ≥2 mg/kg. The cerebrospinal fluid drug concentration measured 2 to 4 h after the dose was 12% (range, 0 to 46%) of the simultaneously measured serum drug concentration. A limited-sampling strategy was developed to estimate the area under the concentration-time curve for concentrations in serum at 2 and 6 h.  相似文献   
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