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Cyclic stretch has been demonstrated to induce proliferative and secretory activities by cultured arterial endothelial and smooth muscle cells, cellular processes that contribute to the development of intimal hyperplasia. A model of an end-to-side anastomosis was developed to examine the hypothesis that regions of the artery at such anastomoses are subjected to facally increased cyclic stretch, which may stimulate the development of intimal hyperplasia. Polytetrafluoroethylene grafts were anastomosed end to side to latex rubber tubes that have elastic properties similar to those of the human femoral artery. Pulse waves with physiologic pressure, rate, and contour were applied, and systolic and diastolic diameters were measured in two planes at longitudinal intervals. Circumferential strain imposed on the latex artery was calculated at each interval. Strain imposed perpendicular to the suture line was also measured. Circumferential strain was consistently maximal at a distinct region of the artery along the proximal third of the anatomosis (6.0±1.1% vs. 3.3±0.5% at other regions of the artery). The maximal strain across the suture line was found at precisely the same region (3.9±0.3% vs. 2.0±0.4%). The anastomotic region of the recipient artery in a distal end-to-side anastomosis is subjected to cyclic circumferential strains two times greater than those experienced by the remainder of the artery. This corresponds to a common location of intimal hyperplasia. Such strains may be a stimulus for intimal hyperplasia.Presented at the Seventeenth Annual Meeting of the Peripheral Vascular Surgery Society, June 7, 1992, Chicago, Ill.  相似文献   
143.
Abbott P 《The Health service journal》1993,103(5355):suppl 6, 9-suppl 6,10
The NHS spends millions on management consultants but often has little idea of who to hire or how to get the best out of them. Philip Abbott shows how the health service can learn a few tricks from the private sector.  相似文献   
144.
Nutrient Intake following Vertical Banded Gastroplasty or Gastric Bypass   总被引:3,自引:3,他引:0  
Background: This study explored eating habits, nutrient intake, and blood vitamin and mineral levels to determine whether severely obese subjects (BMI 40-50 kg m−2) post-vertical banded gastroplasty (VBG) or gastric bypass Roux-en-Y (GBR) are at risk of developing compounded under-nutrition. Methods: A dietary follow-up of 36 VBG and 19 GBR was maintained for 18 months via 7-day food intake diaries and 24-h recalls. Food intake was analysed for energy and nutrient composition and for its relative amount to recommended dietary allowances (RDA). Results: Weight loss was greatest during the first 6 months, continued at a slower rate for the next 6 months, nearly ceasing thereafter. The results following GBR were not substantially different from those following VBG 18 months postoperatively. The median weight loss at 1 year postoperatively was 48, 46, 48 and 36 kg; expressed as residual excess body weight: 0.2, 16, 13 and 22% for GBR Men, Women, VBG Men, Women, respectively. According to the classification proposed by Reinhold, all subjects achieved excellent treatment outcomes 18 months postoperatively. Despite the relatively low reported energy intake (20-50% below RDA), no correlation was found between rate of weight loss and energy intake at 6 months postoperatively. The intake of most vitamins and minerals was below 50% of RDA during the 18 months follow-up. The increase in energy intake did not improve the level of the nonenergy-contributing nutrients. Compliance to multivitamin and mineral supplement intake deteriorated with time. Conclusion: The low to within-normal range of blood vitamin and mineral levels 12 months postoperatively suggests the slow development of subclinical nutritional deficiency which could jeopardize the subjects' long-term health status.  相似文献   
145.
This study was undertaken to determine the effects of a partner-support, incentive-baed educational program on breast feeding knowledge, attitudes and support and to examine the relationship between feeding intentions and feeding behavior among low-income women. Women who expressed a willingness to participate in the intervention were randomly assigned to intervention and usual breast feeding (control) groups. Sixty-eight primipara women, with expected due dates between May and December, 1992, volunteered to participate in the study. Of these, 34 were randomly assigned to each of the two groups. Approximately 81 percent of the women completed the study, leaving n=29 in the control group and n-26 in the intervention group. The intervention consisted of special incentives (prizes) for women and their partners to participate in several breast feeding education and promotion activities. Intervention group women and their partners experienced positive changes in breast feeding knowledge and attitudes. Furthermore, the intervention seemed to have influenced more women in the treatment group to breast feed despite their prenatal feeding intentions. In addition, the partners of intervention group women were perceived to be more supportive of, breast feeding than control group partners. These findings suggest that incentives, such as donated prizes, can be used to attract lower socioeconomic group women and their partners to breast feeding promotion interventions. Participation in such interventions can produce positive changes in breast feeding knowledge, attitudes, and support, and can have a dramatic effect in promoting breast feeding.This study was supported through contract no. 59-3198-1-050 from the Food and Nutrition Service, U.S. Department of Agriculture.  相似文献   
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OBJECTIVE: Examine variation in dietary practices and nutritional intakes of Korean Americans at different acculturation levels. DESIGN: Cross-sectional mail survey. SUBJECTS/SETTING: US national sample of 348 Korean Americans (46% of the Korean American sample to whom questionnaires were delivered). STATISTICAL ANALYSIS PERFORMED: Analysis of variance, Pearson correlation, Spearman rank correlation, chi 2 test, and multiple regression analysis. RESULTS: Korean Americans who were more acculturated consumed more American food and less Korean food. American foods such as oranges, low-fat milk, bagels, tomatoes, and bread were consumed regularly by Korean Americans; Korean foods such as rice, kimchi, garlic, green onions, and Korean soup were also consumed regularly. American foods were adopted the most at breakfast and the least at dinner. Bicultural people regularly incorporated more different types of foods into their diet. Despite significant differences in dietary practices, dietary quality did not vary by acculturation status. APPLICATION/CONCLUSIONS: Acculturation was influential in the dietary patterns of Korean Americans. Specific information about Korean diet related to acculturation status can be used by dietitians who work with Korean Americans. Dietitians can benefit from gathering and applying specific information about Korean diets and diets of other ethnic groups; they also need to recognize the changing nature of dietary patterns as acculturation occurs.  相似文献   
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