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51.
The early stages of platelet accumulation in two types of sealed interposition Dacron grafts implanted in the carotid arteries of sheep have been studied. One type was externally coated with collagen (Haemaguard) while the other experimental conduit had an additional inner lining of the same substance. 32P-labelled platelets were used to assess platelet accumulation and corrections for wall absorption were calculated. The activities in both types of grafts were highest proximally and decreased towards the distal anastomosis. The increases in the doubly-sealed grafts were larger than in those that had been single sealed, presumably reflecting activation of platelets in contact with collagen at the graft-wall and bloodstream interface. In addition, a significantly larger amount of thrombus was formed in the doubly-sealed grafts 4 h after reperfusion. It is reasonable to assume that increased acute thrombogenicity due to direct collagen-blood contact on graft surfaces is unfavourable to long term patency. 相似文献
52.
The impact of gender differences in sexual socialization on early sexual experiences among Norwegian adolescents is discussed.
The material comprises a stratified sample of 920 adolescents ages 16–20 years in a Norwegian county. Data were collected
by means of questionnaires. Of the respondents, 55.5% were girls and 44.5% were boys. 52.3% of girls and 41.4% of the boys
had coital experience. The most common reasons for having had the first sexual intercourse were being in love, curiosity or
excitement, and sexual arousal. Findings from a discriminant analysis showed that emotional reasons were more important to
girls, whereas boys seemed more practical in sexual matters. More boys than girls reported that the reason for having had
their most recent intercourse was that the partner wanted it. This indicates that if girls do not want sex, boys seldom use
pressure. Girls set the premises for sexual interaction but are not as sexually skilled as boys. 相似文献
53.
Work-related hand eczema in atopics 总被引:1,自引:0,他引:1
549 individuals with severe (group 1), 406 with moderate (group 2) atopic dermatitis in childhood, 222 with respiratory allergy but no atopic dermatitis in childhood (group 3), and 199 without personal or family atopy (group 4) were studied as to occupational health symptoms due to hand eczema. In groups 1, 2 and 4, there was a slightly significant difference (P less than 0.05) between the frequency of hand eczema in individuals with and without occupational exposure to chemicals, water, soil or wear (friction). Despite no such work, 55% in group 1 and 44% in group 2 had developed hand eczema. About 1/4 of the atopics in extreme risk occupations, such as ladies' hairdressers and nursing assistants, had not developed hand eczema. Altogether, 9% in groups 1 and 2 and 3% in group 4 had changed their jobs due to hand eczema, the majority from work with to work without exposure to chemicals, water, soil or wear. Social factors had usually contributed to the change. The healing rate after taking up a new occupation was 15% in group 1, 36% in group 2 and 67% (4 out of 6) in group 4. The majority of the patients whose eczema had not healed had improved in their new occupations. It is claimed that medical reasons for change of occupation should be carefully weighed against social reasons. 相似文献
54.
D. Bergqvist C.-G. Björck P. Dougan C.O. Esquivel O. Lannerstad B. Nilsson P. Saldeen T. Saldeen 《Thrombosis research》1985,37(3):435-448
The effect of a selective inhibitor of thromboxane synthesis (dazoxiben) was evaluated in different acute models for thrombosis and hemostasis. Dazoxiben significantly reduced the thrombogenicity of the modified human umbilical vein (Dardik Biograft) inserted in the carotid artery position in sheep. The effect was evident concerning patency, thrombus weight and platelet accumulation at the distal anastomosis. This paralleled a decreased production of thromboxane in both anastomoses and the midgraft region. Dazoxiben did not reduce either the frequency of jugular vein thrombosis (induced by a combination of endothelial damage and flow restriction) or arteriolar microembolism after laser injury in rabbits. Neither did it influence initial hemostasis as evaluated by measuring the hemostatic plug formation in the rabbit mesenteric microcirculation. It is concluded that thromboxane synthesis inhibition may be of value when attempting to improve the performance of small diameter vascular prostheses, the data obtained indicating a low risk for hemorrhagic complications. 相似文献
55.
56.
Clinical implications for the management of acute thromboembolic occlusion of the superior mesenteric artery: autopsy findings in 213 patients 总被引:8,自引:0,他引:8
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OBJECTIVE: To study findings at autopsy in patients with fatal acute thromboembolic occlusion of the superior mesenteric artery (SMA). SUMMARY BACKGROUND DATA: Acute occlusion of the SMA is difficult to diagnose and mortality remains high. In Malmo, Sweden, the autopsy rate between 1970 and 1982 was 87%, creating possibilities for a population-based study. METHODS: Among 23,496 clinical autopsies and 7569 forensic autopsies, 213 cases with acute thromboembolic occlusion of the SMA and intestinal infarction were identified. RESULTS: A clinical suspicion of intestinal infarction was documented in 32% of the patients, only 35% being in the care of surgeons. The embolus/thrombus ratio was 1.4 to 1. Thrombotic occlusions were located more proximally than embolic occlusions (P < 0.001), intestinal infarction was more extensive (P = 0.025) and thrombotic occlusions were associated with old brain infarction (P = 0.048), aortic wall thrombosis (P = 0.080), and disseminated cancer (P = 0.079). Patients with embolic occlusions (n = 122) had a higher frequency of acute myocardial infarction (AMI) than patients with thrombotic occlusions (P = 0.049). The embolic source was identified in 80%. In 115 (94%), synchronous embolism and/or source of embolus were present. There were findings of remaining cardiac thrombi in 58 (48%) and synchronous emboli affected 273 other arterial segments in 83 (68%). CONCLUSIONS: Early recognition and revascularization would have been a prerequisite for survival in at least half of the patients, since the jejunum, ileum, and colon were affected by infarction. A minority of all patients were under surgical care. AMI, cardiac thrombi, and synchronous emboli were common findings among patients with embolic occlusions. 相似文献
57.
Wanhainen A Lundkvist J Bergqvist D Björck M 《Journal of vascular surgery》2005,41(5):741-51; discussion 751
OBJECTIVE: The primary objective of this study was to develop a simulation model to assess the cost-effectiveness of different screening strategies for abdominal aortic aneurysms (AAAs) in men. METHODS: A systematic review of the literature was conducted for different screening strategies in terms of age (60, 65, or 70 years) and risk profiles (all men or specific high-risk groups) of the screened population, and rescreening after 5 or 10 years. These data were analyzed in a Markov simulation cohort model. RESULTS: The cost per life year gained for different screening strategies ranged from US 8,309 dollars to US 14,084 dollars and was estimated at US 10,474 dollars when 65-year-old men were screened once. Screening 60-year-old men was equally cost-effective, with the advantage of more life years gained. We demonstrated a trade-off between high prevalence of AAA and lower life expectancy, eliminating the expected benefits of screening high-risk groups such as smokers (US 10,695 dollars) or cardiovascular patients (US 10,392 dollars). Assuming general population utility resulted in a cost per quality-adjusted life year (QALY) gained of US 13,900 dollars, whereas a hypothetical 5% reduction in utility among men with a screening-detected AAA raised the cost per QALY gained to US 75,100 dollars. CONCLUSION: This Markov model, which was based on a systematic review of the literature, supplied information on the estimated cost-effectiveness of different screening strategies. Screening men for AAA may be cost-effective in the long-term. Different screening strategies and quality-of-life effects related to screening for AAA need to be evaluated in future clinical studies. 相似文献
58.
59.
Background The need for thromboembolism (TE) prophylaxis during laparoscopic surgery is not well established. The aim of this study was to investigate current TE prophylaxis in patients undergoing laparoscopic cholecystectomy (LC) in Sweden.Methods Mail questionnaire to all Surgical Departments in Sweden about the current use of thromboembolism prophylaxis in patients undergoing laparoscopic cholecystectomy.Results The response rate was 78 of 80 departments of surgery (98%). Seventy reported performing LC. Thirty-six percent used thromboembolism prophylaxis in all patients, 17% in most, 9% in half their patients and 39% only rarely. The current use of thromboembolism prophylaxis ranged from low-molecular-weight heparin for 7 days + stockings in all patients to no prophylaxis at all in the majority of patients.Conclusions The use of thromboembolism prophylaxis in LC patients is highly variable, even in the small and homogenous country of Sweden. Further studies concerning the risk of TE complications after laparoscopic surgery are warranted. 相似文献
60.