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111.
EI-2128-1, a novel interleukin-1beta converting enzyme (ICE) inhibitor, was isolated from the culture broths of Penicillium sp. E-2128. EI-2128-1 selectively inhibited human recombinant ICE activity with IC50 value of 0.59 microM, without inhibiting elastase and cathepsin B. EI-2128-1 also inhibited mature interleukin-1beta secretion from THP-1 cells induced by LPS with IC50 value of 0.28 microM.  相似文献   
112.
Human exposure to ethylene oxide (EtO) occurs mainly through inhalation of polluted air in occupational workplaces and/or via tobacco smoke. A significant biochemical reaction of EtO converts the terminal valine of hemoglobin into N-(2-hydroxyethyl)valine (HOEtVal). In the present study, the extent of HOEtVal formation in 360 healthy adults who were not occupationally exposed to EtO was measured with a gas chromatograph/mass spectrometer in the electron-capture negative chemical ionization mode. This parameter was correlated with smoking habits and urinary cotinine concentration, exhibiting a positive relationship between HOEtVal and the number of cigarettes smoked (r2 = .4416). Urinary cotinine measurements also correlated with HOEtVal and the number of cigarettes smoked. This positive correlation between urinary cotinine and HOEtVal (r2 = .3893) provides a new perspective on the early stages of carcinogenic processes.  相似文献   
113.
In this study, a historical phenolic (Bakelite) molding material, BMMA-5353, was tested to determine the airborne concentrations of asbestos fibers released during four different activities (sawing, sanding, drilling, and cleanup of dust generated from these activities). Each activity was performed for 30 min, often in triplicate. The primary objective for testing BMMA-5353 was to quantitatively determine the airborne concentration of asbestos fibers, if any, in the breathing zone of workers. Uses of this product typically did not include sawing or sanding, but it may have been drilled occasionally. For this reason, only small quantities were sawed, sanded, and drilled in this simulation study. Personal (n = 40), area (n = 80), and background/clearance (n = 88) air samples were collected during each activity and analyzed for total fiber concentrations using phase contrast microscopy (PCM) and, for asbestos fiber counts, transmission electron microscopy (TEM). The raw PCM-total fiber concentrations were adjusted based on TEM analyses that reported the fraction of asbestos fibers, to derive a PCM-asbestos concentration that would enable calculation of an 8-hour time-weighted average (TWA). The estimated 8-hour TWAs ranged from 0.006 to 0.08 fibers per cubic centimeter using a variety of worker exposure scenarios. Therefore, assuming an exposure scenario in which a worker uses power tools to cut and sand products molded from BMMA-5353 and similar products in the manner evaluated in this study, airborne asbestos concentrations should not exceed current or historical occupational exposure limits.  相似文献   
114.
Two families are described with members affected by Brown's syndrome. Another case of Brown's syndrome is described in a dizygotic twin. The authors suggest a hypothesis for the influence of heredity in Brown's syndrome.  相似文献   
115.
The personal experience on neurological disturbances associated with early HIV infection and AIDS is reported. Central nervous system (CNS) involvement occurred during the early stages in 3 cases: 2 patients with HIV-seroconversion (CDC category III) and one patient with persistent generalized lymphadenopathy (PGL, III group CDC, 1986). The patients had HIV acute meningitis. The neurological manifestations in AIDS had high incidence (49 of 83 cases), often with multiple aetiology in single patients. We remark the necessity of an early aetiological diagnosis to address the treatment.  相似文献   
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A specific α2 agonist, mivazerol, known to be effective in reducing myocardial ischaemia when given intravenously immediately before an exercise tolerance test, produced a significant increase in exercise duration and time to the onset of angina when given orally over a two week period to 25 patients with stable angina. A non-significant trend to reduction in electrocardiographic signs of ischaemia was also noted. The clinical relevance of this improvement now needs to be tested in larger numbers.


Keywords: α2 agonist; sympathetic activity; myocardial ischaemia; stable angina; exercise tolerance test  相似文献   
119.
Three groups of patients, long-time sufferers from classic migraine, common migraine, and cluster headache respectively, and three control groups, age- education- and sex-matched, underwent a set of neuropsychological tests and tachistoscope tasks in order to evaluate cognitive functions and interhemispheric balance. Migraineurs and cluster headache patients were selected on the basis of the constant (90%) unilaterality of both pain and focal neurological deficits. No significant differences emerged between patients and controls in any of the neuropsychological and tachistoscopic tasks administered, thus indicating that between attacks of migraine as well as of cluster headache no evidence of cortical dysfunction is detectable.  相似文献   
120.
A novel colorimetric assay was developed and validated for accurate quantitation of human immunodeficiency virus (HIV) DNA in peripheral blood mononuclear cells (PBMCs). We tested 318 sequential samples from 56 subjects, 53 of whom were undergoing dual or triple therapy. Patients were considered responders when viremia levels were below 5, 000 HIV RNA copies/ml. The mean DNA copy numbers for untreated and responder subjects were similar (72 and 75, respectively), while it was 4.54-fold higher for nonresponders (339). This report provides strong evidence that HIV DNA levels in PBMCs correlate with therapeutic efficacy and suggests that DNA quantitation is a useful tool to monitor the decay of the HIV reservoir toward disease remission, especially when viremia is undetectable.  相似文献   
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