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991.
992.
A case of hospital acquired endocarditis due to Acinetobacter calcoaceticus in a severely burned patient is presented. Both aortic and mitral native valves were affected and the organism was resistant to most antimicrobial agents.  相似文献   
993.
Imipenem, a new carbapenem antibiotic shows an extremely broad spectrum of antibacterial activity for almost all Gram-negative and Gram-positive aerobic and anaerobic bacteria. It is stable to beta-lactamases and shows a high affinity for PBP 2. The changes in morphology and ultrastructure caused by the antibiotic on Ps. aeruginosa confirm that imipenem acts by binding primarily to PBP 2, resulting in irregular and round shaped cells, and later during treatment to PBP 1 with cellular lysis. The involvement of PBP 1 is also demonstrated by the fast bactericidal kinetics on Ps. aeruginosa, E. coli and Staph. aureus.  相似文献   
994.
Phillipsite dust was intrapleurally administered to random-bred rats by 20 mg in 0.5 ml of saline three times with an interval of a month. Higher incidence of hemoblastoses has been experimentally found in exposed animals compared to the control ones. One rat developed pleural mesothelioma, two rats lung adenocarcinoma. It was concluded that phillipsite has weak carcinogenic activity.  相似文献   
995.
5H-Mebendazole and some related heterocyclic methyl carbamates were synthesized and their anthelmintic activity against Caenorhabditis elegans was determined. In order to study the influence of the heteroaromatic region with regard to the carbamate moiety on biological activity, the molecular electrostatic potentials (MEP) of all structures were calculated and a structure-activity relationship (SAR) was established. The electrostatic pattern of activity includes two minima of the carbamate moiety, a third heterocyclic minimum, and a pi-electronic region.  相似文献   
996.
Due to the long-term study of various machines under industrial and test conditions it became possible to determine the specific role of each chain of the man-machine system in the intensification of vibroacoustic effect on a worker and to develop a system of medical, technical and organizational preventive measures. Introduction of a set of such measures at one of the plants helped to reduce vibration disease rates by dozens of times. In order to control noise- and vibration-caused diseases it was necessary not only to improve machines' quality and service conditions but also to pay special attention to the choice of operators and to the quality of monitoring their adaptation process.  相似文献   
997.
The use of Mixture Toxicity Indices (MTI's) is one of the more attractive approaches for describing and predicting the effects of mixtures of toxicants. For an MTI to apply to all possible mixtures of the compounds in question, it must summarize information from a model describing all possible responses of interest. A method of obtaining MTI's from response surface equations or from tolerance models similar to the toxic units model is presented. Methods of calculating several MTI's with desirable properties from multivariable probit response surfaces are demonstrated.  相似文献   
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