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Teenage pregnancy is a well-documented problem in the United States, with approximately 890,000 teenage pregnancies occurring each year. Although teen pregnancy rates have declined since 1991, rates remain higher than the mid-1970s and are fourfold those of European countries. Substantial morbidity and social problems result from these pregnancies, affecting the mother, her children, other family members, and society. Multiple educational approaches have been used, with few demonstrating significant reductions in teen pregnancy. School-based programs have been diverse and multifaceted. Recently, programs with a comprehensive approach have shown potential for success. In this article, characteristics and elements of promising school-based programs are identified and discussed. It is imperative that school nurses play an active role in developing and implementing prevention programs that incorporate rigorous evaluation. As health educators, school nurses are in a prime position to implement and evaluate the effectiveness of teen pregnancy prevention programs.  相似文献   
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The use of a vascularized jejunal patch for the reconstruction of bile duct injuries is presented. The method has been used in 1 patient with a common bile duct stricture and in 1 patient with a noncircumferential bile duct defect. The procedure has the advantages of technical simplicity, primary mucosal coverage, lasting elasticity, and minimal risk for stricture formation.
Resumen Se presenta el uso de un parche vascularizado de yeyuno para la reconstrucción de lesiones del canal colédoco. Se reseca un segmento móvil del yeyuno lo suficientemente amplio para cubrir el defecto, asegurándose de que existe buena irrigación para el segmento, visualizando los vasos por transiluminación con luz ordinaria. La continuidad del intestino es restablecida mediante anastomosis término-terminal. Se utiliza la parte mesentérica del segmento intestinal, el cual es ascendido por vía retrocólica. Se sutura mucosa con mucosa con una sola capa de puntos separados de ácido poliglicólico 5-0. Se coloca un tubo-en-T para drenaje, el cual es retirado a las 6 semanas. El método ha sido utilizado en un caso de estenosis del colédoco y en un caso con un defecto circunferencial del mismo canal biliar. El procedimiento tiene la ventaja de la simplicidad técnica, la cobertura primaria de la mucosa, la elasticidad permanente y un mínimo riesgo de que se produzca estenosis.

Résumé L'emploi d'un patch jéjunal bien vascularisé pour traiter les blessures de la voie biliaire fait l'objet de l'article. La méthode a été utilisée pour un cas de sténose de la voie biliaire principale et un cas de plaie n'intéressant pas la totalité de la circonférence du canal biliaire. Elle a pour avantages sa simplicité technique et le fait qu'elle assure une couverture muqueuse, sa persistante élasticité et le fait qu'elle présente un risque réduit de sténose.
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The late results--up to six years--after axillo-femoral bypass reconstruction are reported for 85 patients with leg ischaemia who were regarded as poor-risk patients for aortic bypass surgery, or who had aortic graft infection. Velour-Dacron grafts and expanded polytetrafluoroethylene (PTFE, Gore-Tex)--grafts have been used. The cumulative patency rate (life table) six years after graft implantation was 64% (PTFE-grafts) and 58% (Velour-Dacron grafts). The corresponding cumulative limb salvage rate six years after graft implantation was 88% when PTFE grafts were used and 77% when Velour-Dacron grafts were used. Our results demonstrate that axillo-femoral reconstruction is a useful procedure with a good patency rate 6 years after implantation. This procedure should be considered when dealing with poor risk patients with severe leg ischaemia.  相似文献   
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麦冬类中药组织切片计算机三维重建图鉴   总被引:9,自引:0,他引:9  
利用计算机技术实现麦冬类中药组织连续切片三维重建与动态显示,为计算机辅助生药学鉴定和教学提供了新的三维图像技术和研究资料。  相似文献   
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This paper aims to review the evidence for long‐term effectiveness of weight loss on cholesterol, high‐density lipoprotein (HDL), low‐density lipoprotein (LDL) and triglycerides in overweight/obese people. Current evidence is mostly based on short‐term studies. A systematic review of long‐term lipid outcomes of weight loss in studies published between 1966 and 2001, was conducted. Inclusion criteria included all cohort studies and trials carried out on participants with body mass index of greater than or equal to 28 kg m?2. Studies had at least two weight change measurements and follow‐up of more than 2 years. Thirteen long‐term studies with a follow‐up of more than 2 years were included. Cholesterol has a significant positive linear relationship with weight change (r = 0.89) where change in weight explains about 80% of the cholesterol difference variation (Adj R2 = 0.80). For every 10 kg weight loss a drop of 0.23 mmol L?1 in cholesterol may be expected for a person suffering from obesity or are grossly overweight. Weight loss has long‐term beneficial effects especially on LDL and cholesterol. Weight loss in obese patients should be encouraged and sustained.  相似文献   
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Pre-clerking of all patients undergoing elective general surgical operations was introduced at our hospital in an attempt to reduce an unacceptably high operation cancellation rate. A prospective audit has been performed on the effect of this policy on the cancellation rate. Before the introduction of pre-clerking there was a marked seasonal variation in the number of patients who failed to attend for surgery, which could be explained by absence on holiday. This seasonal variation disappeared after the start of pre-clerking clinics, but there has been no reduction in the number of cancellations for medical reasons.  相似文献   
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