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81.
The relationship between in vitro sensitivity to antimicrobials and the outcome of treatment was studied in 228 cows with coliform mastitis. All the cows were treated with a preparation containing sulphonamide and trimethoprim, and 197 of them were also treated with a non-steroidal anti-inflammatory drug (NSAID). The relationship between in vitro sensitivity to sulphonamide/trimethoprim and recovery was analysed by multivariate logistic regression. The possible confounding effects of treatment with an NSAID, days in lactation, parity, herd, and type of infecting organism were tested. Only treatment with an NSAID had a significant confounding effect and was included in the final statistical model. The recovery rate of the 165 cows infected by coliforms that were sensitive to sulphonamide/trimethoprim (89.1 per cent) was higher than that of the 63 cows infected by coliforms that were resistant to sulphonamide/trimethoprim (74.6 per cent). The odds ratio of recovery for the cases associated with organisms that were sensitive to sulphonamide/trimethoprim relative to the cases associated with organisms that were resistant to sulphonamide/trimethoprim was 2.75, with a 95 per cent confidence from 1.25 to 5.85. The odds ratio of recovery for the cases treated with an NSAID relative to the cases treated with sulphonamide/trimethoprim only was 2.76 with a 95 per cent confidence interval from 1.12 to 6.79.  相似文献   
82.
Measures of family stability, sociocultural background, and emotional ties to parents in medical students (N = 589, mean age = 22 years) predicted their social support measures, assessed 23 to 39 years later (mean age = 56 years). Father's education and family's involvement in church were positively associated with group participation (number of group memberships), whereas parental loss between the ages of 11 and 20 was negatively associated with group participation; perceived emotional closeness to parents was positively associated with social closeness (number of close contacts providing emotional and instrumental support). Thus, group participation and social closeness were influenced by distinctly different childhood factors.  相似文献   
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It is generally assumed that folding intermediates contain partially formed native-like secondary structures. However, if we consider the fact that the conformational stability of the intermediate state is simpler than that of the native state, it would be expected that the secondary structures in a folding intermediate would not necessarily be similar to those of the native state. beta-Lactoglobulin is a predominantly beta-sheet protein, although it has a markedly high intrinsic preference for alpha-helical structure. We have studied the refolding kinetics of bovine beta-lactoglobulin using stopped-flow circular dichroism and find that a partly alpha-helical intermediate accumulates transiently before formation of the native beta-sheets. The present results suggest that the folding reaction of beta-lactoglobulin follows a non-hierarchical mechanism, in which non-native alpha-helical structures play important roles.  相似文献   
85.
3D integration review   总被引:1,自引:0,他引:1  
3-D integration delivers value by increasing the volumetric transistor density with the potential benefit of shorter electrical path lengths through use of the shorter third dimension. Several researchers have studied various aspect of 3Di such as bonding level, through silicon via processes and integration, thermomechanical reliability of the vias, and the impact of the vias on devices. In this paper, we review some of the literature with a view to understanding the key options and challenges in 3Di. We al...  相似文献   
86.
The validity of relations established for the calculation of the interfacial area of a liquid flowing along an inclined partially-wetted tube (Part I) was verified experimentally. The measurement of the interfacial area was carried out by means of a chemical method. The variables were: volumetric liquid flow rate, slope angle of the tube, its diameter, and the contact angle, whose value was influenced by the material of the tube. The experimental data were compared with the results calculated according to the method suggested in the Part I of the present study. The results were in a good agreement with the theory in the case of higher contact angles (i.e., for tubes made of steel or PVC), while in the cases where small contact angle values were expected on the basis of theory (glass), the results differed significantly. This discrepancy was attributed to the effect of traces of impurities present in the solution, which accumulated on the surface of tube, bringing about a gradual increase in the contact angle value in the course of experiments. The effect on the lower surface energy materials such as PVC or steel are less marked than on the glass. There is, therefore, the limitation of the theory given in Part I because of the uncertainty of the contact angle to be used for a given situation.  相似文献   
87.
The ultrastructures of colonies of two stable UV-induced morphological mutants and their parental strain of Candida albicans grown on glucose-containing solid medium were investigated by scanning electron microscopy. The structures and ultrastructures of these three types of colonies were determined not only in terms of the proportions of blastospores, hyphae and pseudohyphae, but also with regard to the mode of budding of blastospores and the positions of these particular cell types within the colonies. Hyphae with an atypical appearance and branching characters were observed both in regular-wrinkled and in irregular-wrinkled mutant colonies. Smooth colonies of the parental strain and the mutants exhibited the same hyphal network within the agar, suggesting that micro-environmental factors in the agar overcame the effects of these mutations.  相似文献   
88.
PURPOSE: To examine rheumatology subspecialty practice patterns, determinants of referral to rheumatologists, and utilization of aspiration and injection procedures in a population-based sample of elderly individuals. SUBJECTS AND METHODS: We obtained Medicare physician claims for all visits to rheumatologists among beneficiaries aged 65 years and older in Colorado, Massachusetts, and Virginia in 1993, and for visits to all providers by patients with coded diagnoses of rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). We examined variations in visit frequency and aspiration/injection procedures, and we analyzed determinants of referral to a rheumatologist for RA or SLE. RESULTS: In 1 year, 144,797 visits were made to rheumatologists by 38,443 patients in the three states. An inflammatory disorder was coded in 45% of visits and a noninflammatory disorder in 50%. Half of patients with RA were seen three or fewer times in the year. For RA and SLE, African Americans were about 60% as likely to be seen by a rheumatologist as whites. Utilization of rheumatologist services for rheumatoid arthritis and systemic lupus erythematosus was highest in the state (Virginia) with the lowest per capita supply of rheumatologists. Among patients with bursitis, tendinitis, and osteoarthritis, African-American women were more likely to receive an injection or aspiration procedure than whites or African-American men. CONCLUSION: Elderly patients with rheumatologic disorders were seen by specialists less frequently than recommended by a recent rheumatology manpower survey. African-Americans with RA and SLE had fewer rheumatology visits than whites.  相似文献   
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