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1.
Kim  SH; Chang  KH; Song  IC; Han  MH; Kim  HC; Kang  HS; Han  MC 《Radiology》1997,204(1):239
  相似文献   
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The General Practice Research Club.   总被引:1,自引:1,他引:0       下载免费PDF全文
The General Practice Research Club was established in 1969, and now has 120 members. A meeting of the club is held twice a year, at which various papers, from research ideas through to completed, published studies are presented. A survey of 40 individuals who had presented papers at meetings during the period 1984-89 showed that almost half (18) had presented papers on clinical topics. As a result of the presentation, 29 individuals had modified their research, with 11 undertaking major alterations. The meeting was rated most highly by those offering ideas and plans for research. Most individuals responded positively to the meetings, commenting that they valued peer review, found the meetings encouraging, and useful for focusing ideas. Lack of criticism and feedback was commented upon. The club has an important role to play in encouraging research by service general practitioners.  相似文献   
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In order to determine if serial, noninvasive evaluation of polytetrafluoroethylene (PTFE) vascular access grafts could identify a subgroup of patients at risk for thrombosis, the authors studied flow characteristics, using duplex ultrasonic scanning, in 18 hemodialysis patients with forearm loop grafts. On average, five examinations were performed per patient over the 10-month study period. Seven episodes of thrombosis occurred in six patients. The mean Doppler flow in grafts that subsequently thrombosed was significantly lower than in those that did not (544 +/- 218 ml/min versus 843 +/- 391 ml/min, p less than 0.001). The interval from last examination to thrombosis ranged from 13 to 58 days. At a defined cut-off flow of 450 ml/min, this test yielded a sensitivity of 83% and a specificity of 75% for episodes of thrombosis occurring within 2 to 6 weeks. The authors conclude that episodes of thrombosis in PTFE arm loop grafts are usually preceded by significantly lower Doppler-measured flow than grafts that do not thrombose and that it may be possible, by this means, to identify grafts at risk.  相似文献   
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Gastric cancer still represents the second most common cause of gastrointestinal cancers in Germany. A disturbing issue is that at the time of diagnosis there are less than 15% of patients for whom a cure can be achieved. Nowadays, biological, histomorphological, molecular genetic and epidemiological data suggest that Helicobacter pylori eradication may lead to the prevention of gastric pre-neoplastic lesions and even gastric cancer. At present, eradication can be offered to selected patients and populations at increased risk, but more research is required before embarking on general and global H. pylori eradication for gastric cancer prevention. The main challenge is to determine how long mucosal abnormalities remain reversible and gastric cancer development can be halted.  相似文献   
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P N Lee  J S Fry  B A Forey 《Thorax》1990,45(9):657-665
Trends in smoking associated respiratory diseases in England and Wales during 1941-85 have been studied, with careful attention to problems caused by changes in classification of cause of death. Three diseases were selected for analysis: lung cancer, emphysema, and chronic obstructive lung disease. During 1971-85 deaths that would previously have been certified under chronic bronchitis have increasingly tended to be classified under chronic airways obstruction. The definition of chronic obstructive lung disease that was used includes both terms to avoid the artificial decline caused by consideration of chronic bronchitis in isolation. Age specific rates for all three diseases show a pronounced cohort (period of birth) pattern, rates for men rising up to the rates for those born shortly after the turn of the century and then declining, and rates for women peaking in the cohort born 20-25 years later. For chronic obstructive lung disease, but not for lung cancer and emphysema, the cohort peak is superimposed on a sharply declining downward trend. In both sexes cohort patterns of cumulative cigarette consumption peak at a time broadly similar to those seen for the three diseases. Trends in cigarette consumption, however, cannot explain the underlying steeply declining rate of chronic obstructive lung disease. Nor can they fully explain the declining trends in lung cancer and emphysema rates in younger men and women.  相似文献   
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