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5-Chloropyrazinamide and 5-chloropyrazinoic acid were evaluated for in vitro activity against Mycobacterium tuberculosis, Mycobacterium bovis, and several nontuberculous mycobacteria by a broth dilution method. 5-Chloropyrazinamide was more active than pyrazinamide against all organisms tested. It is likely that this agent has a different mechanism of action than pyrazinamide. 相似文献
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To determine the usefulness of bone scans in detecting metastatic disease in women with early stage breast cancer, records of 193 patients who had bone scans preformed and underwent breast conservation therapy at a single institution were reviewed. Patients with invasive T1 or T2 breast carcinomas were eligible for this study; patients with a true positive bone scan were excluded from conservation therapy and, thus, were excluded from this study. The incidence of false positive bone scans in this study population was 32.6% (63/193 patients). Patients over 50 years of age had a significantly greater incidence of false positive bone scans (p<0. 05). In the 63 patients with false positive bone scans, 101 radiographs were performed to exclude metastatic disease in areas of increased uptake identified on bone scan. No significant difference in the rate of false positive bone scans was seen in relation to tumor size, pathologic or clinical nodal status or hormone receptor activity of the primary tumor. Thus, selective use of bone scans is advocated in patients with early stage (T1 or T2) breast cancer. 相似文献
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A study was conducted where the GPs in a district answered a questionnaire on reasons for hospital admission, divided into the categories: needed hospital investigation, hospital treatment, or needed care and nursing. They judged whether the admission could have been prevented. Finally, a multidisciplinary panel discussed ways to obtain better courses of admission. Of 266 admissions, 40 (15%) were due to a need for care and nursing. Ninety-seven (37%) of the admissions could be replaced by a short one-day stay, and 52 (20%) could have been postponed until the next day if that was possible. The panel discussion showed that municipalities can do more to strengthen the local professional support. It is concluded that the interface between primary care and the hospital should offer better opportunities for one-day admissions or sub-acute admissions, and that municipalities must be more aware of their responsibility for the care of fragile and ill people. 相似文献
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Colonization of the nasopharynx by a middle ear pathogen is the first step in the development of otitis media in humans. The establishment of an animal model of nasopharyngeal colonization would therefore be of great utility in assessing the potential protective ability of candidate vaccine antigens (especially adhesins) against otitis media. A chinchilla nasopharyngeal colonization model for nontypeable Haemophilus influenzae (NTHI) was developed with antibiotic-resistant strains. This model does not require coinfection with a virus. There was no significant difference in the efficiency of NTHI colonization between adult (1- to 2-year-old) and young (2- to 3-month-old) animals. However, the incidence of middle ear infection following nasopharyngeal colonization was significantly higher in young animals (83 to 89%) than in adult chinchillas (10 to 30%). Chinchillas that had recovered either from a previous middle ear infection caused by NTHI or from an infection by intranasal inoculation with NTHI were completely protected against nasopharyngeal colonization with a homologous strain and were found to be the best positive controls in protection studies. Systemic immunization of chinchillas with inactivated whole-cell preparations significantly protected animals not only against homologous NTHI colonization but also partially against heterologous NTHI infection. In all protected animals, significant serum anti-P6 and anti-HMW antibody responses were observed. The outer membrane P6 and high-molecular-weight (HMW) proteins appear to be promising candidate vaccine antigens to prevent nasopharyngeal colonization and middle ear infection caused by NTHI. 相似文献
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Aiming at finding out the ergonomics conditions of the nursing personnel in a hospital admission unit, the authors utilized as a methodological presupposition the search for a global experienced work situation through the analysis of some elements as: the man (nursing worker); the work activity (prescribed duty, real activities and work position) and the environment (temperature, noise and illumination). The authors selected the Cardiology admission unit for the site of their research. The results verified that the nursing workers the mentioned unit face problems related to salaries, work installations, relationship, work organization, levels of formation and the activities executed. The authors suggested some recommendations. 相似文献
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