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971.
Löwe  Benedikt  Welch  Philip D. 《Studia Logica》2001,68(1):21-41
We describe the solution of the Limit Rule Problem of Revision Theory and discuss the philosophical consequences of the fact that the truth set of Revision Theory is a complete 1/2 set.  相似文献   
972.
In response to my "How to Make Naturalism Safe for Supernaturalism: An Evaluation of Willem Drees's Supernaturalistic Naturalism" (Rottschaefer 2001), Willem Drees maintains that I have misunderstood his purpose and views and have failed to make the case against his view that naturalism is intrinsically limited. In this response, I comment on these concerns.  相似文献   
973.
In the present study the effects of a wide range of doses of the dopamine release inhibitor CGS 10746B were evaluated in spontaneous activity and in aggressive behaviour using the paradigm of isolation‐induced aggression. The two higher doses (8 and 16 mg/kg) produced a decrease in spontaneous motor activity. Antiaggressive effects were observed after administration of doses from 4 mg/kg upwards. At this dose, CGS 10746B diminished threat and attack, and although an increase in immobility was observed, no impairment of other motor behaviours was presented. With higher doses, aggression was practically abolished but with a concomitant effect on many other behaviours. When animals were separated depending on their latency of attack, those that showed a long attack latency (LAL) presented a stronger response to 4 mg/kg than those that had a short attack latency (SAL), which were not affected in their aggression by this dose. We can conclude that presynaptic dopamine function is necessary for the normal expression of aggressive behaviours, since CGS 10746B reduces aggression at doses that do not affect spontaneous motor activity. Aggr. Behav. 27:382–390, 2001. © 2001 Wiley‐Liss, Inc.  相似文献   
974.
This paper presents a new polychoric instrumental variable (PIV) estimator to use in structural equation models (SEMs) with categorical observed variables. The PIV estimator is a generalization of Bollen’s (Psychometrika 61:109–121, 1996) 2SLS/IV estimator for continuous variables to categorical endogenous variables. We derive the PIV estimator and its asymptotic standard errors for the regression coefficients in the latent variable and measurement models. We also provide an estimator of the variance and covariance parameters of the model, asymptotic standard errors for these, and test statistics of overall model fit. We examine this estimator via an empirical study and also via a small simulation study. Our results illustrate the greater robustness of the PIV estimator to structural misspecifications than the system-wide estimators that are commonly applied in SEMs. Kenneth Bollen gratefully acknowledges support from NSF SES 0617276, NIDA 1-RO1-DA13148-01, and DA013148-05A2. Albert Maydeu-Olivares was supported by the Department of Universities, Research and Information Society (DURSI) of the Catalan Government, and by grant BSO2003-08507 from the Spanish Ministry of Science and Technology. We thank Sharon Christ, John Hipp, and Shawn Bauldry for research assistance. The comments of the members of the Carolina Structural Equation Modeling (CSEM) group are greatly appreciated. An earlier version of this paper under a different title was presented by K. Bollen at the Psychometric Society Meetings, June, 2002, Chapel Hill, North Carolina.  相似文献   
975.
cdt1和geminin是重要的细胞周期相关因子,参与细胞周期的调控cdt1与某些疾病的发生有着密切的关系,geminin是cdt1的抑制因子,他们间的平衡对DNA复制;;基因稳定以及细胞周期的调控起着重要的作用,并已经在一些感染性疾病和肿瘤中证实  相似文献   
976.
慢性乙型肝炎是我国常见的慢性传染病之一,严重危害人民健康。围绕着乙型肝炎的防治,带来巨大的经济负担,已成为不可忽视的社会问题。在慢性乙型肝炎-肝硬化-HCC的发生发展过程中,HBV病毒载量起着重要的作用,抗病毒治疗是目前治疗慢性乙型肝炎的有效手段。因此,要重视和规范抗病毒治疗。  相似文献   
977.
针对目前乙型肝炎的抗病毒治疗现状以及临床用药中存在的问题进行分析,就如何选择合理治疗方法提出医疗原则,认为对于慢性乙型肝炎的抗病毒治疗,应坚持联合治疗和个体化治疗,长期用药和间断反复用药结合,把病毒抑制到最低水平,以使发生原发性肝癌的可能性减至最小。  相似文献   
978.
SF-36量表用于慢性乙型肝炎生命质量测定的效果评价   总被引:1,自引:0,他引:1  
评价SF-36量表在慢性乙型肝炎患者中应用的效果;调查101名慢性乙肝患者,用重测信度、分半信度、内部一致性、结构效度和判别效度等对SF-36量表进行评判;该量表具有良好的分半信度和内部一致性,结构效度和判别效度较好;SF-36量表可用于慢性乙型肝炎患者生命质量评价。  相似文献   
979.
视觉工作记忆更新操作过程独立于刺激类型   总被引:1,自引:0,他引:1  
采用4×2被试内设计和2-back视觉工作记忆更新任务,探讨不同刺激类型对任务的影响,并且分离更新任务中的操作与存储成分。结果发现,字母、具体意义的汉字、抽象意义的汉字以及图片的更新任务成绩没有差异,表明更新是一种程序化的认知过程,独立于刺激类型;不同材料的再认成绩存在差异,字母的再认率低于其它三种材料,汉字的再认率也略低于图片,表明更新任务中的存储与更新操作是相互独立的过程,在作业任务上可以产生分离。  相似文献   
980.
The objective of this document is to provide recommendations for the genetic counseling of patients and families undergoing evaluation for neurofibromatosis type 1 (NF1) or who have received a diagnosis of NF1. These recommendations are the opinions of a multi-center working group of genetic counselors with expertise in the care of individuals with NF1. These recommendations are based on the committee’s clinical experiences, a review of pertinent English language medical articles, and reports of expert committees. These recommendations are not intended to dictate an exclusive course of management, nor does the use of such recommendations guarantee a particular outcome. These recommendations do not displace a health care provider’s professional judgment based on the clinical circumstances of an individual patient. Both Heather B. Radtke and Courtney D. Sebold contributed equally to this document.  相似文献   
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