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排序方式: 共有438条查询结果,搜索用时 46 毫秒
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S. Suominen I. Antti-Poika K. Tallroth S. Santavirta P. Voutilainen T. S. Lindholm 《Archives of orthopaedic and trauma surgery》1996,115(5):276-279
A total of 113 patients underwent a cemented total hip replacement (THR) operation involving femoral component fixation either without the use of a distal intramedullary plug (n = 57, group 1) or with the plug (n =56, group 2). We studied the femoral component fixation radiographically at on average 6 years after THR. The cement coating was assessed as technically good in 86% and 95% of groups 1 and 2, respectively. There was radiographically diagnosable loosening of the femoral component at the follow-up in 25 cases in which stems were inserted without the intramedullary plug, and in 6 cases in those with the plug (P < 0.0008), and the mean subsidence of the femoral component was 5 mm in group 1 and 1.5 mm (P < 0.0003) in group 2, respectively. Osteolytic changes around the femoral component were noticed in both groups in equal numbers and with no statistical difference. The use of a distal intramedullary plug in the cementation of the femoral stem results in a better cement coating, reduces femoral component subsidence and ameliorates the loosening rates. 相似文献
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In a follow up study of 34 patients with premature adrenarche we examined serum adrenal androgen levels and growth. The majority (28/34) showed an upward bend in the growth curve which, at the mean age of 2.3 years, preceded other signs of adrenarche on average by 3.8 years. Pubertal growth spurt was missing or reduced in 50% of the patients (8/16), however, final height did not differ from that expected from parental heights. Adrenal androgens did not remain elevated at adolescence. The mean age at menarche for all the girls was 0.5 years younger than in the general population.Conclusion Our findings imply that premature adrenarche may start earlier than previously recognized. Compared to ordinary growth these children seen to use a greater part of their potential for adult height already at that early age. 相似文献
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OBJECTIVE: To test whether the advantages of the ultrasonically activated shears (UAS) observed in thyroidectomies in a previous matched-pair study could be repeated in a randomized trial. SUMMARY BACKGROUND DATA: The UAS has been documented, mainly in nonrandomized studies, to be a safe and fast device in video-assisted and conventional surgery. METHODS: Thyroidectomies and lobectomies performed for benign or malignant thyroid disease between August 1997 and January 1999 were included in this series. Separate randomization, resulting in four sets of envelopes, was done for one consultant endocrine surgeon and for senior residents for both lobectomies and for total thyroidectomies. The operations performed with the UAS were compared with operations performed with the conventional method, using ligatures as the main hemostatic method. Main outcome measures were operating time, postoperative serum calcium level, palsy of the recurrent laryngeal nerve, and amount of intraoperative and postoperative bleeding. Possible bias that could have been caused by imbalance between treatment groups for surgeon experience was tested by two-way analysis of covariance. RESULTS: Thirty-six patients were randomized, 19 to the UAS and 17 to the conventional group. Mean operating time was 99.1 minutes in the UAS group and 134.9 minutes in the conventional group. The average savings in operating time with the UAS was thus 35.8 minutes. There was no difference in complications between the groups. The estimated savings in operating time would have been 1.66 times that observed in this study if the groups had been unbalanced with reference to surgeon experience. CONCLUSION: The UAS is a usable device in total thyroidectomies and lobectomies. 相似文献
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Activated protein C decreases plasminogen activator-inhibitor activity in endothelial cell-conditioned medium 总被引:12,自引:0,他引:12
van Hinsbergh VW; Bertina RM; van Wijngaarden A; van Tilburg NH; Emeis JJ; Haverkate F 《Blood》1985,65(2):444-451
Confluent cultures of endothelial cells from human umbilical cord were used to study the effect of activated human protein C (APC) on the production of plasminogen activators, plasminogen activator-inhibitor, and factor VIII-related antigen. Addition of APC to the cells in a serum-free medium did not affect the production of tissue-type plasminogen activator (t-PA) or factor VIII-related antigen; under all measured conditions, no urokinase activity was found. However, less plasminogen activator-inhibitor activity accumulated in the conditioned medium in the presence of APC. This decrease was dose dependent and could be prevented by specific anti-protein C antibodies. No decrease was observed with the zymogen protein C or with diisopropylfluorophosphate-inactivated APC. APC also decreased the t-PA inhibitor activity in endothelial cell-conditioned medium in the absence of cells, which suggests that the effect of APC is at least partly due to a direct effect of APC on the plasminogen activator- inhibitor. High concentrations of thrombin-but not of factor Xa or IXa-- had a similar effect on the t-PA inhibitor activity. The effect of APC on the plasminogen activator-inhibitor provides a new mechanism by which APC may enhance fibrinolysis. The data suggest that activation of the coagulation system may lead to a secondary increase of the fibrinolytic activity by changing the balance between plasminogen activator(s) and its (their) fast-acting inhibitor. 相似文献
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Virtanen JK Voutilainen S Alfthan G Korhonen MJ Rissanen TH Mursu J Kaplan GA Salonen JT 《Journal of internal medicine》2005,257(3):255-262
OBJECTIVE: Based on case-control and prospective studies elevated blood total homocysteine (tHcy) has been suggested to be an independent risk factor for cardiovascular diseases (CVD). The purpose of the study was to explore the joint effect of increased serum tHcy concentration and other risk factors on the risk of CVD mortality in middle-aged men without a history of heart disease or stroke. DESIGN: A prospective, population-based Kuopio Ischaemic Heart Disease Risk Factor (KIHD) Study. SETTING: Eastern Finland. Subjects. A total of 802 men aged 46-64 years, examined in 1991-93. MAIN OUTCOME MEASURES: CVD mortality event. RESULTS: The mean serum tHcy concentration was 10.8 micromol L(-1) (SD 3.3). During the average follow-up time of 10.8 years 50 men experienced a CVD death. The hazard rate ratio for CVD mortality was 1.80 (95% confidence interval: 1.02-3.19) in men in the highest serum tHcy third versus lower thirds after adjustment for cardiovascular risk factors. Furthermore, elevated serum tHcy concentration appeared to increase the risk of CVD death in men who smoke or who have high circulating concentrations of serum total or LDL cholesterol, apo-B apolipoprotein or plasma fibrinogen. CONCLUSION: We conclude that homocysteine may increase the risk of CVD mortality in middle-aged men from Eastern Finland, and it may especially increase the risk when present with other risk factors for CVD. 相似文献
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