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991.
Academic underachievement frequently is associated with attention-deficit/hyperactivity disorder (AD/HD); however, the role of variables beyond AD/HD symptoms and cognitive mediators is unknown. Further, whether prediction models vary (a) relative to non-AD/HD students, (b) between math and reading, and (c) based on how achievement is defined has not been examined. Multiple measures (e.g., teacher ratings and behavior observations) were examined as predictors for concurrent achievement outcomes (standardized achievement test scores and report card grades) in math and reading in two samples of 1st through 4th grade children (136 with AD/HD, 53 without AD/HD). Teacher perceptions of academic skills were the strongest predictors of achievement test scores for both groups, while academic skills and enablers accounted for reading report card grades in children with AD/HD but not their normal counterparts. Implications of these findings for school-based assessment and intervention for students with AD/HD are discussed.  相似文献   
992.
The dialog between Staddon (2001, 2004) and Baum (2004) raises general questions about the nature of scientific peer review. Their dialog displays effects on peer review of differences of opinion about the relative merits of local and global analyses. Baum (1995, 1997, 2001, 2002) favors global analyses as a paradigm different, newer, and better than the local, dynamic, real‐time approach that plays a significant role in Staddon (2001). According to the Kuhnian perspective (Kuhn, 1996) Baum advocates, we can better understand his review of Staddon (2001) by considering the implications for it of his commitment to the idea that a global analysis is a superior scientific paradigm. This commentary examines some characteristics of local and global analyses, as well as some of their possible implications for peer review in the context of a reviewer's belief in the Kuhnian idea of incommensurability: According to this idea, a reviewer who either is, or who believes he is, from one paradigm is unlikely, for better or worse, to understand or perhaps even tolerate work from a different paradigm. It is recommended that a process be developed to encourage “truth in peer reviewing” to reduce possible conflicts of interest embedded in the current conception of scientific peer review.  相似文献   
993.
Roeper  Peter 《Studia Logica》2004,77(3):425-438
Peter Gärdenfors has developed a semantics for conditional logic, based on the operations of expansion and revision applied to states of information. The account amounts to a formalisation of the Ramsey test for conditionals. A conditional A > B is declared accepted in a state of information K if B is accepted in the state of information which is the result of revising K with respect to A. While Gärdenfors's account takes the truth-functional part of the logic as given, the present paper proposes a semantics entirely based on epistemic states and operations on these states. The semantics is accompanied by a syntactic treatment of conditional logic which is formally similar to Gentzen's sequent formulation of natural deduction rules. Three of David Lewis's systems of conditional logic are represented. The formulations are attractive by virtue of their transparency and simplicity.  相似文献   
994.
GABA‐A receptor is a transmembrane hetero‐oligomeric protein which consists of five subunits, the combination of which confers unique pharmacological properties to the receptor. It is well‐known that the GABAergic system is involved in the modulation of aggression. However, the role of α5/GABA‐A receptors has not been explored. In this study, we examined the effect of L‐655,708 (0.625‐5 mg/kg), a selective ligand for the benzodiazepine site of GABA‐A receptors which contain the α5 subunit, on agonistic behavior elicited by isolation in male mice. Individually housed mice were exposed to an anosmic “standard opponent” 30 min after drug administration, and the encounters were videotaped and evaluated using an ethologically based analysis. L‐655,708 (5 mg/kg) exhibited an ethopharmacological profile characterized by a marked reduction of the time spent in offensive behavior (threat and attack) without affecting immobility, accompanied by a significant increase of avoidance/flee and nonsocial exploration behaviors, suggesting that the antiaggressive effect of the drug is unselective. Overall, this behavioral profile might indicate the existence of an anxiogenic‐like activity of L‐655,708 in mice. Aggr. Behav. 30:319–325, 2004. © 2004 Wiley‐Liss, Inc.  相似文献   
995.
"尿布与啤酒"对医学科研的启示   总被引:1,自引:0,他引:1  
简单介绍了基于文本的揭示文献间关联的两种方法,即相关文献和非相关文献的知识发现的方法,并对这两种方法在医学科研中的作用进行了阐述.  相似文献   
996.
运用医学哲学的原理,分析了现代医学模式存在的弊端,阐述了现代医学精神是科学和人文精神的统一,结合临床医生综合素质的培养,指出了现代医学科学和人文精神统一的重要性.  相似文献   
997.
心、脑科学与医学人道主义价值观   总被引:1,自引:0,他引:1  
当今,心、脑科学的研究进展及成果极大支持了科学的医学人道主价值观应当以正确认识、把握、运用脑模式科学假说为基础的观点.试从意识的本质、医学人道价值观的机制、与价值相关的医者心灵的自我控制和意志自由等三个方面探讨心、脑科学同医学实践中的医学人道价值观的关系.  相似文献   
998.
结核病诊治进展与科技革命   总被引:2,自引:0,他引:2  
现代科技革命极大地促进了结核病各方面的发展.微生物学和免疫学的发展,揭示了结核病的病因、发病机制、病理生理的本质,分子生物学技术使结核病的基础研究不仅停留在器官、细胞水平,而是深入到蛋白质、核酸、基因的水平;基因治疗的方法可望从根本上治疗结核病.高新技术的产物如X线照片、电子计算机断层扫描、纤维支气管镜检查和新药的出现等极大地提高了临床诊治的能力.借助于各种先进的医疗设备而进行精确的诊断,基因治疗将成为一种崭新的治疗手段.  相似文献   
999.
从反义RNA到RNA干扰:科学突破的机遇与创新   总被引:1,自引:0,他引:1  
RNA干扰是近年发现的存在于真核细胞内的一种重要防御机制,现已发展成为一种全新的基因阻断技术,广泛用于抗病毒、抗肿瘤和后基因组时代基因功能研究.它是在反义RNA研究中意外获得的重大科学突破,其发现过程对科学研究有重要启示意义.  相似文献   
1000.
思维策略训练对高中生化学问题解决能力影响的实验研究   总被引:6,自引:1,他引:5  
吴鑫德  张庆林  陈向阳 《心理科学》2004,27(5):1049-1051
研究思维策略训练对于高中生解决化学计算问题的有效性。被试为1616名高中学生,训练由经过培训的17名高中化学教师承担,时间为10周,实验采用自编的《高中生化学计算问题解决思维策略训练教程》及《自我提示卡》,在真实的课堂教学情境和正常的教学秩序下进行,以探索化学学科问题解决思维策略训练的有效性。结果表明:思维策略训练能显著地提高高中生的化学计算问题解决能力,且普通中学高中生的训练效果明显优于重点中学。  相似文献   
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