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71.
72.
Current synthetic vascular prostheses do not acquire lining of vascular endothelium in humans or dogs. Endothelial seeding of vascular grafts has been proposed as a means of reducing the thrombogenicity of these grafts. We examined feasibility of cultivating endothelial cells (EC) by tissue culture technique and their subsequent seeding onto small diameter polytetra fluoroethylene (PTFE) grafts. Twenty adult dogs underwent common carotid artery interposition with 4 mm PTFE grafts. Ten dogs received seeded and the remaining ten received unseeded grafts. Grafts were removed at 4 and 12 weeks and their gross/morphological features compared. Cumulative patency rates for seeded grafts were 70% as compared to unseeded ones 30%. Seeded grafts were completely surfaced with a mono-layer of endothelium by 4 weeks. Small graft patency appears to be related to the establishment of an endothelial surface, the development of which is clearly facilitated by seeding with autogenous endothelium.KEY WORDS: Endothelial cell seeding, Vascular grafts  相似文献   
73.
The group B beta-hemolytic streptococcus is responsible for an escalating frequency of neonatal meningitis. Of the 18 consecutive cases we report in this study, the mortality was 17%. Among the 15 survivors, there were two children with extensive neurological and psychological impairment. There were no major differences between the survivors and controls in tests of hearing and language function, social skills, and psychological testing. There was a greater number of minor neurological signs among the study group. The mortality and morbidity of group B beta-hemolytic streptococcal meningitis is apparently substantially less than that of all other types of neonatal bacterial meningitis.  相似文献   
74.
The Heartbeat Award (HBA) scheme is a national nutrition labelling scheme that operates throughout England. The aim of this study was to assess whether the implementation of the HBA scheme in the workplace results in an improvement in eating habits at work. A longitudinal survey of employees using a structured questionnaire pre- and post-HBA intervention in six workplaces in Leicestershire, England, was conducted. A qualitative food frequency questionnaire was used to assess dietary behaviour 6 months before the scheme was implemented and 6 months afterwards. Four HBA workplaces (n = 453 employees) were compared with two comparison workplaces (n = 124 employees). The outcome measures for dietary change were consumption of 20 food items, i.e. 16 food-frequency and four food-type items. Changes in pre-intervention data compared with post-intervention data evaluated the impact of the HBA on eating habits. Differences were considered statistically different at the p < 0.05 level. Crude and adjusted odds ratios were used to assess differences in change in dietary behaviour between the intervention and comparison workplaces. The results showed that there was significantly more positive change in intervention workplaces only (i.e. the changes were not detected in the comparison workplaces) for four of the 20 food items tested: increase in consumption of fruit (p = 0.029); reduction in consumption of fried foods (p = 0.044) and sweet puddings (p = 0.042); and change to lower fat milks (p = 0.034). In conclusion, the HBA had a modest impact on dietary intake, resulting in a significant positive change in four out of 20 foods consumed by employees in HBA-holding premises.  相似文献   
75.
OBJECTIVES: To characterize esophageal body and lower esophageal sphincter (LES) motor function in very premature infants. STUDY DESIGN: Esophageal manometry was performed in 12 very premature infants of 26 to 33 weeks' postmenstrual age (PMA) (body weights of 610-1360 g). Esophageal motor patterns were recorded for 30 minutes with a perfused micromanometric sleeve assembly (outer diameter, 2.0 mm). RESULTS: Esophageal pressure waves triggered by dry swallows were predominantly (84%) peristaltic in propagation sequence. All infants showed tonic LES contraction; the mean resting LES pressure (LESP) for individual infants ranged from 5.0 +/- 4.1 mm Hg to 20.0 +/- 4.8 mm Hg. In all infants the LES relaxed (duration, 5.8 +/- 3.0 seconds; nadir pressure, 1.8 +/- 2.6 mm Hg) in response to pharyngeal swallows. Transient LES relaxations (TLESRs) (duration, 21.7 +/- 8.7 seconds; nadir pressure, 0.1 +/- 1.8 mm Hg) occurred on average 2.6 +/- 1.6 times per study; 86% of these relaxations triggered esophageal body common cavity events known to be associated with gastroesophageal reflux. CONCLUSIONS: Esophageal motor function is well developed in very premature infants. Our data also suggest that TLESR is the predominant mechanism of reflux in these babies.  相似文献   
76.
Pediatric manpower in Canada: a cross-country survey.   总被引:2,自引:2,他引:0       下载免费PDF全文
Health care costs and government cutbacks in Canadian training posts have caused concerns about physician manpower. To determine the present pediatric manpower situation a cross-country survey was undertaken of all pediatricians and their practice patterns. Of the 2060 recipients of a questionnaire 5% were found to not be pediatricians. Of the remaining 1960, 69% returned a completed questionnaire. Overall, 70% of the pediatricians were men, although among those less than 35 years of age 49% were women. Across Canada 37% of the pediatricians practised primary care, 25% secondary care and 38% tertiary care. There were wide regional differences in practice patterns, with large numbers of primary care pediatricians in Winnipeg, Toronto, Ottawa and the province of Quebec; few pediatricians in the Maritimes and the remainder of western Canada practised primary care. Non-Canadian graduates accounted for 33% of the pediatricians and represented a considerable proportion of tertiary care pediatricians. Cutbacks in numbers of pediatric training positions and restrictions on immigration of foreign pediatricians may lead to unexpected deficiencies in the availability of some types of pediatric practitioners, especially those in tertiary care.  相似文献   
77.
This article discusses the notorious Cleveland child sexual abuse programme. The inherent defects in and adverse consequences of the programme are highlighted, and the lessons to be learned from it spelled out.  相似文献   
78.
Open-ended interviews with 107 patients documented specific patient expectations of radiologic procedures during which there was no direct radiologist-patient interaction. Patient expectations could be classified into those related to the facility and those related to interactions with radiology staff. Among facility-related expectations, waiting time far outweighed all other concerns. Interpersonal skills were the predominant expectation of radiology staff. The role of the radiologist in fulfilling patient expectations was less clear. Only 10% of unprompted patients cited the radiologist as a factor in their expectations. When patients were specifically prompted to discuss the radiologist's role, communication skills, accuracy of interpretation, and interpersonal skills were the predominant concerns.  相似文献   
79.
80.
Transabdominal versus endovaginal pelvic sonography: prospective study   总被引:1,自引:0,他引:1  
Transabdominal and endovaginal pelvic sonograms were obtained in 108 nonpregnant patients referred for pelvic sonography. The studies were independently obtained by two radiologists and interpreted on the basis of identical clinical information. The sonograms were then compared for anatomic detail and abnormalities. A determination was made about which examination, if either, was superior. Follow-up was performed through a review of the medical records and follow-up studies. Overall, the endovaginal study was judged superior in 65 cases (60.2%), equal in 39 (36.1%), and inferior in four (3.7%). The authors conclude that the endovaginal examination can effectively replace the transabdominal examination as the initial approach for routine pelvic sonography.  相似文献   
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