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Handedness is the most important behavioural asymmetry due to its intimate association with the specialisation of the brain for language. It exists in 3 forms, namely right, left and mixed. Left-handers constitute the biggest minority group in the world and in many aspects they are in a disadvantaged position compared to right-handers. Numerous studies demonstrated association between left-handedness and different health problems ranging from learning disorders to breast cancer and decreased longevity. This paper reviews the relevant literature on the genesis of handedness and connection between handedness and health. Deviations from the “normal” pattern of braininess observed in some left-handers might contribute to developmental, cognitive and some mental disorders. However increased incidence of some of pathological conditions among sinistrals could hardly be explained by the “abnormal” pattern of braininess or by the action of a gene or genes responsible for handedness determination. Review of literature suggests that many of health problems of left-handers develop due to environmental, developmental and other mechanisms related to genesis of handedness.  相似文献   
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苯丙胺诱发小鼠激怒反应及其机制   总被引:1,自引:0,他引:1  
徐建华  沈洪  章元沛 《药学学报》1992,27(8):566-571
苯丙胺15mg/kg ip能诱发小鼠激怒反应,使小鼠出现攻击和殴斗行为。强安定药、弱安定药和利血平有明显拮抗效果。镇静剂如巴比妥类、抗胆碱药及抗肾上腺素药均无拮抗作用。金刚胺、左旋多巴和阿扑吗啡均能增强苯丙胺的激怒效应。因苯丙胺激怒小鼠的方法简便易行,可作为筛选抗精神病药的动物模型。苯丙胺产生激怒作用的机制与增强多巴胺能神经的功能有关,推测可能是促进边缘系统多巴胺释放的结果。  相似文献   
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多索茶碱及其片剂的高效液相色谱分析   总被引:3,自引:0,他引:3  
多索茶碱及其片剂的高效液相色谱分析刘春胜,何秀峰,王云萍,谷士杰,周同惠(中国医学科学院、中国协和医科大学药物研究所,北京100050)多索茶碱(doxofylline)是用于治疗支气管哮喘合并支气管痉挛的慢性阻塞性肺部疾病的新一代黄嘌吟衍生物,其药...  相似文献   
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Passive cutaneous anaphylaxis (PCA) assay has been a gold standard method to measure allergen-specific IgE antibody (ASIgE Ab) levels in allergy mouse models. Many factors including stringent guidelines for laboratory animal use make PCA a difficult choice. Therefore, alternative methods are needed that can be readily applied for measurement of specific IgE antibody levels in mouse serum. Herein we describe a novel ELISA-based method that is more sensitive in comparison to PCA, IgE isotype-specific (because it has little cross-reactivity with IgG1 or IgG2a isotype) and highly reproducible (<10% inter- or intra-assay variation). Furthermore, we demonstrate the utility of this assay to measure specific IgE Ab against a variety of food extracts including chicken egg, peanut, almond, filbert/hazelnut and sweet potato. These findings are of particular interest to those who are seeking (i) to measure food-extract-specific IgE antibody in animal models and (ii) an alternative to the animal-based PCA method to measure mouse IgE antibodies.  相似文献   
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We previously demonstrated the therapeutic effects of ethinyl estradiol (EE), an orally active estrogen and a component of birth control pills, in encephalitogenic autoimmune encephalomyelitis (EAE). In this study, we report the effectiveness of EE in treating collagen-induced arthritis (CIA) induced with bovine type II collagen (bCII) in DBA/1LacJ mice, a CIA susceptible strain. Both low and high doses of EE notably suppressed clinical and histological signs of CIA in a dose-dependent manner compared to vehicle-treated controls. Oral treatment with EE decreased proliferation and secretion of pro-inflammatory factors, TNF-alpha IFN-gamma, MCP-1 and IL-6 by bCII peptide-specific T cells, production of bCII-specific IgG2a antibodies, and mRNA for cytokines, chemokines and chemokine receptors in joint tissue. This is the first report demonstrating effective treatment of joint inflammation and clinical signs of CIA with orally administered ethinyl estradiol, thus supporting its possible clinical use for treating rheumatoid arthritis in humans.  相似文献   
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Anaplastic large cell lymphoma of T/null-cell type (ALCL) is associated with a characteristic genetic abnormality t(2;5) that results in the NPM-ALK chimeric gene and the protein product derived thereof. In 10% to 20% of ALCLs, the translocation partners of the ALK gene are genes other than NPM (variant translocations). ALK gene expression limited to the cytoplasm implies a variant translocation. In this study, we have investigated 46 cases of ALCL for expression and localization of ALK protein and its association with Epstein-Barr virus (EBV) (by hybridization to EBV-encoded nuclear RNA-1 [EBER-1] and immunostaining for LMP-1). ALCL patients with a null cell phenotype were significantly younger as compared with those of T-cell phenotype (mean age: 28 years v 42 years; P =.018). Sixteen of 46 ALCL cases (34%) were ALK positive. ALK-positive patients were significantly younger (mean age: 25 years for those with both cytoplasmic and nuclear staining; 22 years for those with exclusive cytoplasmic staining; and 41 years for those negative for the ALK gene; P =.023). EBER-1 was detected in 9 of 46 cases (20%), and LMP-1 expression was noted in 5 of them. By polymerase chain reaction analysis, all EBV-associated cases that were investigated showed type I EBV. Whereas 2 of 23 T-cell ALCLs (9%) were EBER-1+, and 7 of 23 null-cell ALCLs (30%) showed EBV association (P =.057). EBV association was seen in 20% of ALK-negative cases, in 0% of cases with ALK gene expression in both nucleus and cytoplasm, and in 60% of cases with ALK gene expression exclusively in the cytoplasm (P =.02). Further, although ALK-positive-EBER-1+ cases were LMP-1 negative, ALK-negative-EBER-1+ cases were LMP-1 positive. Our study raises the question whether EBV might have an etiological role in the evolution of ALCLs that lack classical t(2;5).  相似文献   
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PURPOSE: To understand the views of U.S. medical school deans about their primary care faculties. METHOD: In 2000, the authors mailed a questionnaire containing 43 multipart items to deans of 130 U.S. allopathic medical schools. The questionnaire assessed the deans' attitudes about and evaluation of primary care at their school and their school's efforts to strengthen it. Deans were asked to compare family medicine, general internal medicine, and general pediatrics with nonprimary care clinical departments at their schools. RESULTS: Of the 83 (64%) deans who responded, 82% reported their school had departments or divisions of family medicine, general internal medicine, and general pediatrics. Deans rated general internal medicine and general pediatrics higher than nonprimary care faculty on clinical expertise and productivity (p < .001) and family medicine equivalent to nonprimary care faculty. Deans rated all three primary care faculties superior to nonprimary care faculty for teaching skills (p < .001) and programs (p < .05), but lower than nonprimary care disciplines for research productivity (p < .01) and revenues (p < .001). They rated family medicine and general pediatrics lower for research skills (p < .001), but 73% of deans stated research was equally important for primary care and nonprimary care departments. Deans considered overall financial resources to be equivalent for primary care and nonprimary care departments, but 77% of deans felt primary care departments or divisions needed financial support from the medical school to survive. Most deans attempted to strengthen primary care by changing the curriculum to promote primary care and by providing financial support. CONCLUSIONS: Deans ranked primary care faculty high on clinical and teaching measures. Although they considered research to be an important activity for primary care faculty, they evaluated it low relative to nonprimary care departments.  相似文献   
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