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101.
From March 1994 to September 1996, 39 patients underwent stenting of the unprotected left main coronary artery because of high surgical risk. Stenting appeared to improve clinical outcome, but there was a significant mortality rate at long-term follow-up.  相似文献   
102.
Two new antibiotics, hongoquercins A and B, were isolated from fermentation extracts of the unidentified fungus LL-23G227. In the optimum medium, titers of the A and B components reached approximately 2.1 g/liter and 0.02 g/liter, respectively. The optimum temperature for antibiotic production was approximately 22 degrees C. Growth was delayed at 15 degrees C but appeared to reach higher levels than was observed at 22 degrees C. Addition of dextrose to growth media increased hongoquercin B production. Hongoquercin A exhibited moderate activity against Gram-positive bacteria. Mechanistic studies conducted in an E. coli imp strain suggested membrane damage as the primary mode of bactericidal action. These compounds also lysed human red blood cells, suggesting a similar mode of action on eukaryotic cells.  相似文献   
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Propofol is a new, fast-acting intravenous (i.v.) anesthetic. Involuntary movements or epileptic seizures have occurred during or after propofol-induced anesthesia in approximately 50 reported cases; a third of the patients have had epilepsy. We report 5 patients with seizures in association with propofol anesthesia. A female epileptic patient developed severe status epilepticus; the other patients with short-lasting seizures had no previous epilepsy. Although propofol has been used in treatment of patients of status epilepticus, the risk of precipitation of epileptic seizures warrants consideration especially when planning anesthesia for epileptic patients.  相似文献   
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Clinical observations of 1365 children with the lymph nodes affection were summarized. The diagnosis verification was conducted using the broad arsenal of general clinical and special methods of investigation. In complicated situations the histochemical and immunogenetic methods were applied for the diagnosis. The structure and dynamics of children's morbidity with lymphadenopathies (LAP) was studied up, the age, sexual and seasonal peculiarities were systematized, the analysis of primary localizations and clinico-morphological comparisons was conducted. The basic thesises of the standardized approach were elaborated on the ground of the diagnostical and tactical mistakes results analysis.  相似文献   
107.
The idea of a long and stable career rewarded by retirement is a fixture of the American social ethos and political economy. The paradox is that many Americans' careers do not fit this image. Here, we examined how the structure of the career, as compared to only those circumstances proximate to retirement, is important for understanding career endings. Based on labor force histories drawn from the National Longitudinal Survey of Older Men, we observed that the occupational roles held through the mid and late career combine additively to influence retirement and disability experiences, with different conditions of work coming into play depending on the career stage. Occupational roles in the mid career also have long-term, indirect effects, operating through the onset of health problems and the adequacy of pension benefits. Although retirement and disability are not hinged to occupational mobility per se, these career endings are sensitive to major discontinuities in the career and work role in terms of unemployment and labor force mobility.  相似文献   
108.
D-Glucal and a series of substituted derivatives have been tested as substrates, inhibitors and inactivators of the Agrobacterium faecalis beta-glucosidase in order to probe structure/function relationships in this enzyme. D-Glucal is shown to be a substrate (kcat = 2.3 min-1, Km = 0.85 mM) undergoing hydration with stereospecific protonation from the alpha-face to yield 2-deoxy-beta-D-glucose. 1-Methyl-D-glucal surprisingly serves as only a poor substrate (kcat = 0.056 min-1, Km = 57 mM), also undergoing protonation from the alpha-face. 2-Fluoro-D-glucal, however is completely inert, as a result of inductive destabilisation of the oxocarbenium ion-like transition state for protonation, and functions only as a relatively weak (Ki = 24 mM) inhibitor. Similar behaviour was seen with almond beta-glucosidase and yeast alpha-glucosidase and for the interaction of 2-fluoro-D-galactal with Escherichia coli beta-galactosidase. A series of of alpha, beta-unsaturated glucal derivatives was also synthesised and tested as potential substrates, inhibitors or inactivators of A. faecalis beta-glucosidase. Of these only 1-nitro-D-glucal functioned as a time dependent, irreversible inactivator (ki = 0.011 min-1, Ki = 5.5 mM), presumably acting as a Michael acceptor. Electrospray mass spectrometric analysis revealed multiple labeling of the enzyme by this inactivator, lessening its usefulness as an affinity label. Less reactive Michael acceptor glycals which might have been more specific (1-cyano-, 2-cyano-, 1-carboxylic acid, 1-carboxylic acid methyl ester) unfortunately did not function as inactivators or substrates, only as relatively weak reversible inhibitors (Ki = 3-96 mM).  相似文献   
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