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41.
A prognostic index for 2-year survival after recovery from acute myocardial infarction was constructed from variables obtained during its course. One hundred ten of 143 patients survived 2 years, and 27 of 33 patients died of cardiac-related causes. Univariate analysis showed that 12 variables were significantly different between the surviving and nonsurviving groups. Discriminant analysis indicated five variables with meaningful predictive value to be included in a prognostic index: admission systolic blood pressure; highest blood urea nitrogen level in the cardiac care unit: atrial arrhythmias in the cardiac care unit; angina pectoris for more than 3 months or a previous myocardial infarction; and more than one ventricular ectopic beat per hour recorded on a dynamic electrocardiogram during the 17th to 24th hospital day. The prognostic index emphasizes the importance of extensive myocardial impairment and provides a means for identifying patients at risk of early mortality.  相似文献   
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Survival, recoverability and sublethal injury of two strains of Listeria monocytogenes, Scott A and an environmental strain KM, on exposure to sea water at 12.8 or 20.8 degrees C was determined using in situ diffusion chambers. Plate counts were used to assess recoverability and injury while 5-cyano-2,3-ditolyl tetrazolium chloride (CTC) reduction was used to determine respiratory activity. T90 values (times for 10-fold decreases in numbers of recoverable cells) on non-selective medium (trypticase soya agar with 0.6% yeast extract) at 12.8 and 20.8 degrees C were 61.7 and 69.2 h for L. monocytogenes Scott A, and 103.0 and 67.0 h for L. monocytogenes KM, respectively. On selective medium (Oxford agar), T90 values at 12.8 and 20.8 degrees C were 60.6 and 56.9 h for L. monocytogenes Scott A, and 83.0 and 65.9 h for L. monocytogenes KM, respectively. With Scott A, the percentage of sublethally injured cells at 12.8 and 20.8 degrees C was 1.7 and 17.7%, respectively, while for KM the values were 19.0 and 1.6%, respectively. The fraction of cells reducing CTC but which were not recoverable on plating progressively increased on exposure to sea water. Listeria monocytogenes KM challenged at 58 degrees C showed an apparent increase in heat resistance after exposure to sea water at 20.8 degrees C for 7 d (D58 = 2.64 min) compared with before exposure (D58 = 1.24). This increase in thermal resistance was not apparent at temperatures greater than 63 degrees C, and analysis of the best-fit regression lines fitted to the thermal data obtained from the two cell populations indicated that their thermal resistance was not significantly different (P > 0.05) over the temperature range tested (58-62 degrees C).  相似文献   
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This paper describes the frequency of susceptibility of Gram-negative and Gram-positive bacteria against antibacterial agents. The data are based on all susceptibility tests performed in 1996 at the Department of Medical Microbiology of the University of Zurich and at the private medical laboratory "medica" in Zurich. The evaluation of the results from 1975 to 1996 shows that susceptibilities against the antimicrobial agents tested have not changed markedly in this period with few exceptions. The tables may be a help for the physician in his decision for a "calculated chemotherapy" of bacterial infections.  相似文献   
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Patients with segmental bone and joint replacement prostheses because of tumors increasingly need revision surgery because of their long term survival. Between 1970 and 1990, 208 custom prosthetic replacements were performed for limb salvage in patients with tumors. Reoperations were required in 52 patients. The mean time to reoperation was 37 months. The reoperation procedures included 35 prosthetic revisions, 11 amputations, four arthrodeses, one vascularized fibular graft, and one open reduction and internal fixation of a fracture with supplemental bone graft. Functional assessment using the new Musculoskeletal Tumor Society scoring system was available for the 36 living patients, and their mean rating was 63% (18.9) at 12 years' mean followup. Of the 35 patients who received a new prosthesis, 12 (33%) patients needed a third operation at mean followup of 68 months. The probability of prosthetic survival in the group of 35 patients needing revision to the same or another prosthesis was 79% at 5 years and 65% at 10 years. The chance and frequency of needing reoperation increased as patients survived longer. Reoperations for tumor recurrence or infection usually resulted in amputation. Reoperation for failed initial segmental bone and joint prosthetic replacement is feasible and effective and can be done without jeopardizing subsequent patient and implant survival or without significantly affecting functional results compared with the values before reoperation.  相似文献   
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In recent years new curing agent technology has been developed which allows water-based curing agents to be introduced into high performance coating, these are classified according to the type of epoxy resin used. Type I utilises low molecular weight, liquid epoxy resins and Type II pre-formed dispersions of higher molecular weight solid epoxy resins. The chemical composition of the binder of water-borne epoxy coatings plays a critical role in their performance properties, hence some of the structural properties of the amine hardeners will be reviewed. New curing agents will be discussed which demonstrate the versatility these products can offer to the coating formulator. Performance data of clear coats and anti-corrosive primers confirm the applicability of the new systems for the long term protection of steel and concrete surfaces.  相似文献   
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