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91.
SETTING: Government Medical College, Nagpur, India, a tertiary care hospital. OBJECTIVE: To estimate the effectiveness of mass neonatal BCG vaccination in the prevention of pulmonary tuberculosis in Nagpur, India. DESIGN: A hospital-based pair-matched case-control study with a case of 1:3, including 144 cases of pulmonary tuberculosis and 432 controls. RESULTS: The overall vaccine effectiveness estimated in the present study was 60% (95% Confidence Interval [CI] 43%-72%). The protective effect was more in males in the age group 21-30 years. The prevented fraction was 39% (95% CI 24%-52%). CONCLUSION: The moderate effectiveness demonstrated in this study needs to be substantiated for other forms of tuberculosis by undertaking community-based case-control studies, before attempting to justify the use of mass neonatal BCG vaccination strategy as a part of the national programme.  相似文献   
92.
In this study, a systematic and detailed investigation on liquid-liquid extraction of sulfur olive oil miscella in hexane with aqueous ethanol solutions was performed. Optimal extraction conditions for recovery of free fatty acids (FFA) with a minor loss of neutral oil were determined in bench-scale single-stage extractions. It was concluded that, to ensure deacidification with a low triglycerides loss, it is appropriate to extract the miscella with 30% or more dilute ethanol solutions. It was also noted that under these circumstances the free fatty acid percentage extracted is not affected by increases in contents of FFA and partial glycerides of sulfur olive oil, and the solvent must be saturated with hexane before extraction. Changing the oil:hexane ratio in miscella from 1:2 to 2:1 by weight did not have any significant effect on extraction results.  相似文献   
93.
A monosynaptic response was recorded in vivo in the mushroom body of the bee brain, an important site for memory consolidation. Focal electrical stimulation of a major afferent input evoked an extracellular field potential that consisted of a presynaptic fiber volley and a postsynaptic response. We report a long-lasting potentiation of the synaptic response (2.6-fold increase; < or = 3.5 h). Potentiation of the response was induced by low-frequency stimulation (0.02-1.0 Hz), was input specific, and was maintained in the absence of stimulation. Paired-pulse facilitation of the response was converted to paired-pulse depression after potentiation, suggesting a presynaptic mechanism. This is the first demonstration of long-term synaptic plasticity in the insect brain.  相似文献   
94.
We showed previously that the glycolipoprotein fraction prepared from Leptospira interrogans inhibited the Na+,K+ ATPase enzyme purified from brain or kidney and in isolated nephron segments (M. Younes-Ibrahim, P. Burth, M. V. Castro Faria, B. Buffin-Meyer, S. Marsy, C. Barlet-Bas, L. Cheval, and A. Doucet, C. R. Acad. Sci. Paris Ser. III 318:619-625, 1995). In the present communication, we have demonstrated that unsaturated fatty acids such as oleic and palmitoleic acids, which are adsorbed to this fraction, are effective inhibitors of the enzyme.  相似文献   
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PURPOSE: To evaluate the spatiotemporal evolution of radiosurgical induced changes both in metastases and in normal brain tissue adjacent to the lesions by serial magnetic resonance (MR) imaging. METHODS AND MATERIALS: Thirty-five intracranial metastases of different primaries were treated in 25 patients by single high-dose radiosurgery. MR images acquired before radiosurgery were available in all patients. Sixty-three follow-up MR studies were performed in these patients including T2- and contrast-enhanced T1-weighted MR images. The average follow-up time was 9 +/- 5 months (mean +/- standard deviation [SD]). Based on contrast-enhanced T1-weighted MR images, tumor response was radiologically classified in the following four groups: stable disease was assumed if the average tumor diameter after treatment did not show a tumor shrinkage of more than 50% and an increase of more than 25%, partial remission as a shrinkage of tumor size of more than 50%, a disappearance of contrast-enhancing tumor as a complete remission, and an increase of tumor diameter of more than 25% as tumor progress. Moreover, we analysed signal changes on T2-weighted images in brain parenchyma adjacent to the enhancing metastases. RESULTS: The overall mean survival time was 10.5 +/- 7 months, with a 1-year actuarial survival rate of 40%. Stable disease, partial or complete remission of the metastatic tumor was observed in 22 patients (88%). Central or homogeneous loss of contrast enhancement appeared to be a good prognostic sign for stable disease or partial remission. This association was statistically significant (p < 0.05). Three patients (12%) suffered from tumor progression. In eight patients (32%) with stable disease or partial remission, signal changes on T2-weighted images were observed in tissue adjacent to the contrast enhancing lesions. A progression of the high signal on T2-weighted images was seen in seven of the eight patients between 3 and 6 months after therapy, followed by a signal regression 6-18 months after irradiation. CONCLUSION: MR imaging is a sensitive imaging tool to evaluate tumor response as well as the presence or absence of adjacent parenchymal changes following radiosurgery. Loss of homogeneous or central contrast enhancement on Gd-enhanced MR images appeared to be a good prognostic sign for tumor response. Tumor shrinkage seems not to be dependent on time. In addition, most cases of radiation induced changes in normal brain parenchyma observed on T2-weighted images seem to be self limited.  相似文献   
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BACKGROUND: Prevention of hypothermia during abdominal surgery by insulating or heat-transferring methods has been the subject of numerous investigations. This study approaches the problem from a less discussed point of view, i.e. the effect of different surgical techniques on body temperature changes. METHODS: Body temperature was measured at 3 core and 6 skin points in 40 patients scheduled for cholecystectomy through open laparotomy or laparoscopy with pneumoperitoneum created and maintained with unwarmed carbon dioxide (CO2) insufflation. End-tidal CO2 was kept constant by adjustments of respiratory frequency. Anaesthesia, intravenous infusions, and draping of the patients were standardized. RESULTS: During the first 1 h of anaesthesia core temperatures decreased approximately by 0.7 degrees C and distal skin temperatures increased by 7 degrees C in both groups. At the end of surgery heat balance was similar in both groups. An increase of 2.5 1.min-1 in respiratory minute volume was needed to control end-tidal CO2 levels in the laparoscopy group during pneumoperitoneum which was maintained with a CO2 flow of 1.2 1.min-1 through the abdominal cavity. CONCLUSION: Laparoscopic technique with unwarmed carbon dioxide insufflation does not offer any advantage in terms of body temperature changes when compared to open surgery.  相似文献   
100.
The HBsAg status and demographic data of 2480 pregnant women who attended antenatal clinics at Maternal and Child Health Centres in Hong Kong were collected by means of a self-administered questionnaire over a 1-week period in July 1996, to explore the underlying reason of a higher than expected HBsAg prevalence. Local women constituted 49.2% of the sample, mainland Chinese 39.7% and others 11.1%. The overall HBsAg prevalence was 10.0%. When related to place of birth, those born in Hong Kong had a prevalence of 8.4% whereas the prevalence of those born in mainland China was 13.1% (P < 0.001). The overall HBsAg carriage rate is high because of a higher rate in immigrants in the community. It is apparent that the HBsAg prevalence of local people in Hong Kong has been decreasing in the past decade. Overall, the current HBsAg carriage rate in the local adult population is estimated to have declined to about 8%.  相似文献   
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