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991.
目的了解2009年内蒙古盟市、旗县(区)两级健康教育机构与人力资源现状。方法采用《2009年健康教育所(中心)业务工作调查表及基本情况调查表》(卫统46表)对内蒙古盟市、旗县(区)两级健康教育机构设置、人力资源、经费和活动形式进行问卷调查。结果全区12个盟市中有7个盟市级健康教育所为独立建制;104个旗县(区)均有健康教育机构,其中有20个为独立建制。盟市、旗县(区)两级分别有专职健康教育人员73人和190人,两级机构人员学历以本科(40.7%)和大专(39.5%)为主,职称构成均以中级(36.5%)和初级(39.16%)为主,医学背景(公共卫生或临床医学)人员比例仅为人员总数的32.3%。两级健康教育机构的经费主要来源于财政拨款,健康教育机构的工作形式主要有印刷小册子、折页、宣传画、举办健康知识讲座等。结论内蒙古自治区健康教育存在管理体制不顺,专业人员数量偏少、整体素质偏低,财政投入不足,活动形式过于老化与单一等突出问题,需要在医药卫生体制改革中得到解决。  相似文献   
992.
993.
Aim:  To investigate the occurrence of hand eczema after 20 years in schoolgirls previously patch‐tested to nickel.
Methods:  In 1982–83, 960 schoolgirls, aged 8, 11 and 15 years, were investigated for the occurrence of nickel allergy (Larson‐Stymne B and Widström L, Contact Dermatitis 1985:13:289–293). The girls were patch‐tested and the prevalence of nickel allergy was 9%. Twenty years later, the same individuals have received a questionnaire regarding hand eczema and factors of importance for the development of hand eczema. After two reminders, the response rate was 81%.
Results:  In total 17.5% of the girls reported hand eczema after the age of 15. The 1‐year prevalence of hand eczema was 12.6%. Of the previously patch‐tested schoolgirls who answered the questionnaire, 63 were sensitive to nickel. In this study, the prevalence of hand eczema among those 63 was 16%, compared to 17% in the non‐sensitive group (NS). Excluding persons with atopic dermatitis, the prevalence of hand eczema was 12.5% in the nickel‐sensitive group, and 10% among the others (NS). 32% of the persons who had had atopic dermatitis reported hand eczema after 15 years of age, compared to 10% of those with no history of atopic dermatitis (p < 0.001).
Conclusion:  Contact allergy to nickel in early childhood (8–15 years) did not seem to increase the prevalence of hand eczema later in life. The prevalence of hand eczema was increased by a factor of three among those with a history of atopic dermatitis, which is in accordance with earlier reports.  相似文献   
994.
995.
A case of lipomatous meningioma is reported. This is a rare variant of meningioma in which metaplasia of meningoepithelial cells occurs and mature adipocytes are present within the tumour. The heterogeneous attenuation and heterogeneous enhancement visualized on computed tomography (CT) can mimic necrotic malignant tumours. However, the demonstration of fat attenuation within the tumour explains the heterogeneity and suggests a benign process. The differential diagnosis of an extra-axial fat-containing tumour should include lipomatous meningioma.  相似文献   
996.
997.
998.

Background  

Conventional knee and hip implant systems have been in use for many years with good success. However, the custom design of implant components based on patient-specific anatomy has been attempted to overcome existing shortcomings of current designs. The longevity of cementless implant components is highly dependent on the initial fit between the bone surface and the implant. The bone-implant interface design has historically been limited by the surgical tools and cutting guides available; and the cost of fabricating custom-designed implant components has been prohibitive.  相似文献   
999.
1000.
Several hydrazine derivatives (HD) tested so far have pharmacological activities, but many also have toxic side effects, including carcinogenesis. Their toxicity has been ascribed to carbocations (via formation of azoxy intermediates), alkyl radicals or reactive oxygen species. Cytotoxicity and transformation by carbocations is widely accepted, but the role of alkyl radicals is still questioned. We have investigated the cytotoxicity of HD to mouse fibroblasts in three activation systems in which enhanced alkyl radical formation is demonstrated by electron spin resonance/spin-trapping. Cytotoxicity was assayed by inhibition of [3H-methyl]thymidine uptake into DNA of Balb/c 3T3 and/or Myc 9E fibroblasts (normal Balb/c 3T3 cells over-expressing the c-myc proto-oncogene). Based on the results obtained in the cytotoxicity assays we also investigated the transforming potential of procarbazine (PCZ) and methylhydrazine (MeH) activated by horseradish peroxidase (HRP) using the Myc 9E cell line, which aims at the activation of a second cooperating oncogene. Our results show that: (i) cytotoxicity of HD to mouse fibroblasts is increased by HRP activation of MeH, phenelzine and PCZ, which displayed enhanced alkyl radical formation, but not of 1,2-dimethylhydrazine (DMH), which did not produce increased alkyl radical formation under these conditions; (ii) cytotoxicity of neutrophil-activated MeH (producing a 10-fold higher concentration of methyl radicals), is more pronounced than DMH; (iii) MeH and DMH activated by prolonged auto-oxidation in 24-h incubations have comparable cytotoxicity and alkyl radical formation; and (iv) PCZ and MeH activation by HRP to alkyl radicals increased the transformation induced in Myc 9E cells. Taken together, our results strongly support a role for hydrazine-derived alkyl radicals in HD- induced cytotoxicity and cell transformation.   相似文献   
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