首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   444篇
  免费   65篇
  国内免费   14篇
  2024年   5篇
  2023年   2篇
  2022年   4篇
  2021年   8篇
  2020年   9篇
  2019年   18篇
  2018年   22篇
  2017年   13篇
  2016年   20篇
  2015年   12篇
  2014年   22篇
  2013年   76篇
  2012年   14篇
  2011年   22篇
  2010年   14篇
  2009年   21篇
  2008年   19篇
  2007年   23篇
  2006年   22篇
  2005年   25篇
  2004年   26篇
  2003年   11篇
  2002年   25篇
  2001年   10篇
  2000年   8篇
  1999年   9篇
  1998年   8篇
  1997年   7篇
  1996年   5篇
  1995年   7篇
  1994年   6篇
  1993年   5篇
  1992年   4篇
  1991年   2篇
  1988年   2篇
  1987年   1篇
  1986年   2篇
  1985年   1篇
  1983年   2篇
  1982年   1篇
  1980年   1篇
  1979年   6篇
  1977年   2篇
  1976年   1篇
排序方式: 共有523条查询结果,搜索用时 15 毫秒
201.
幸福感:认知与情感成分的不同影响因素   总被引:52,自引:2,他引:50       下载免费PDF全文
以304名城市成年人为被试,以生活满意度、对生活质量的评价为认知指标,以快乐感、正向情感、负向情感为情感指标,调查了其幸福感的现状及影响因素.结果发现:(1)城市成年人对生活质量的评价、生活满意度、快乐感等较高,即他们有较高的幸福感.(2)幸福感的认知和情感指标的影响因素是不尽相同的.总体上看,生活质量评价、生活满意度这两个幸福感的认知指标主要受年龄、收入、人际支持、亲密度四个因素的影响;而正向情感、负向情感和快乐感作为幸福感的情感指标,主要受人际支持、支持的利用度、亲密度和适应性四个因素影响.  相似文献   
202.
在科学与伦理之间——人胚胎干细胞研究向何处去   总被引:3,自引:0,他引:3  
人胚胎干细胞的研究使我们不得不在科学与道德之间作选择。治疗性克隆是如帕金森氏病、糖尿病等许多疾病的最有潜力的治疗方法。体细胞核转移是治疗性克隆关键步骤,因此治疗性克隆与克隆人只有一步之遥。科学史证明,科学的进步给人类带来了许多福利而不是灾难。我们不能低估人类理性的力量。  相似文献   
203.
人类干细胞研究的伦理学争论   总被引:3,自引:0,他引:3  
关于干细胞研究的伦理学争论越来越成为热门话题。2000年8月23日,美国卫生研究所颁布了涉及人类多能胚胎干细胞研究的指南。指南允许联邦政府资助的研究者进行干细胞研究,但是按照布什总统2001年8月9日的决定,政府只资助有限制的干细胞研究。而在英国、法国、日本、澳洲、以及其他国家,干细胞研究不仅在私人的实验室里而且也在政府的实验室里进行着。无论如何,人类干细胞研究应该按照一定规范谨慎进行。  相似文献   
204.
人类胚胎干细胞的伦理学应用   总被引:1,自引:1,他引:0  
人类胚胎干细胞研究和使用面临很多问题,并且大部分已经进行了广泛的讨论,但目前仍有一些问题很少进行讨论。对这些问题的讨论将有助于更好地研究人类胚胎干细胞的使用问题,这些问题是:(1)干细胞研究与社会政策,各个国家有关的政策制定并不一致,除了禁止人的生殖性克隆的国际性公约外,国际性准则在胚胎研究的也没有提供明确的规定;(2)欧洲有些国家在相关的问题的立法一致性上存在着许多问题,有些甚至是相互预报的;(3)干细胞研究应用的预防原则的适宜性问题已引起人们的争论;(4)有利及避免浪费原则在干细胞研究中的应用。  相似文献   
205.
精原干细胞是精子发生的起始,精原干细胞既能分化产生成熟精子又具有自我更新能力以维持自身数量的恒定。精原干细胞移植技术应用于治疗男性不育症,只需将一定数量的供体干细胞植入到受体睾丸的精曲小管内,就能重新建立生精功能。显然,精原干细胞移植在治疗男性不育症有广阔的前景,同时使传统的道德伦理面临着前所未有的困惑。  相似文献   
206.
胰岛移植作为治疗1型糖尿病较理想的方法,由于其供体不足而受到限制。干细胞具有极强的自我更新能力与多向分化潜能,可成为提供1型糖尿病胰岛β细胞良好的细胞来源。造血千细胞移植通过诱导免疫耐受,修复受损胰腺组织改善胰岛功能。间充质干细胞移植可分化为胰岛β细胞,且通过免疫调节改善胰岛细胞微环境。  相似文献   
207.
Scientific Self-Regulation—So Good, How Can it Fail?   总被引:1,自引:1,他引:0  
To be a functional alternative to government regulation, self-regulation of science must be credible to both scientists and the public, accountable, ethical, and effective. According to some, serious problems continue in research ethics in the United States despite a rich history of proposed self-regulatory standards and oversight devices. Successful efforts at self-regulation in stem cell research contrast with unsuccessful efforts in research ethics, particularly conflicts of interest. Part of the cause for a lack of success in self-regulation is fragmented, disconnected oversight, and failure to embody genuine scientific and public consensus. To be accountable, credible and effective, self-regulation must be inclusive and multidisciplinary, publicly engaged, sufficiently disinterested, operationally integrated with institutional goals, and must implement a genuine consensus among scientists and the public. The mechanisms of self-regulation must be sufficiently broad in their oversight, and interconnected with other institutional forces and actors, that they do not create fragmented solutions.
Patrick L. TaylorEmail:
  相似文献   
208.
Clinical and imaging studies suggest that the cerebellum is involved in language tasks, but the extent to which slowed language production in cerebellar patients contributes to their poor performance on these tasks is not clear. We explored this relationship in 18 patients with cerebellar degeneration and 16 healthy controls who completed measures of verbal fluency (phonemic and semantic), word stem completion, and oral naming speed. Cerebellar patients showed significantly slower response times when naming common nouns, which correlated with their degree of motor impairment. Patients were significantly impaired on both phonemic and semantic fluency measures compared to controls (p < 0.001), even when naming speed was entered as a covariate (p = 0.03). On the word stem completion task, patients were significantly less accurate (p < 0.001), had more errors due to non-responses (p = 0.008), and were slower to respond (p = 0.036) than controls; group effects were significant for overall accuracy, but not response time, when the effects of naming speed were covaried (p = 0.014). These findings suggest that cerebellar patients’ poorer performance on language tasks cannot be explained solely by slower language production, and that the integrity of cerebellar-prefrontal loops might underlie poorer performance on measures of executive function in cerebellar patients.  相似文献   
209.
Stephen M. Modell 《Zygon》2007,42(3):629-642
Recent developments in the use of cow egg cells to clone human somatic cells, and the grafting by researchers at several universities of human neurons into mice, bring the notion of the chimera, a mixture of several living organisms, from myth into reality. In his article “Cross‐Species Chimeras: Exploring a Possible Christian Perspective,” Neville Cobbe considers the religious arguments overlying the creation of human‐nonhuman chimeras. In my commentary I focus on the distinction between germline‐ and tissue transplant‐related chimeric techniques implicit in Cobbe's essay and argue that the former poses more serious moral difficulties than the latter if the chimeric product is brought to term. The substantive view of the imago Dei, or image of God, serves as a scaffold by which to judge the permissibility of chimera creation using stem cell and other tissue implants. While useful for judging the rights of such artificially generated beings, I argue that specific criteria such as proportion of tissue uptake, mental capacity, and adherence with the organism's telos are more appropriately considered within a composite image of the living being reflecting its unique integrality. Human co‐creativity with the Divine will inevitably prompt attempts to generate medically useful chimeras. Religious dialogue, combined with the categories of religious moral argument appearing in Cobbe's essay, will help to establish the outline of feasible policy guidelines addressing the complexities inherent in the creation of chimeras.  相似文献   
210.
The mental health histories of the 448 children 15 and 16 years of age who were admitted to state-operated children's psychiatric inpatient services in New York during 1982 were reviewed for the 11 year period through April 1993, Thirty-three percent were served as adults (after age 18) in the state-operated adult civil mental health system; 42% of these individuals were still receiving services at the end of the period. 113 of the 146 individuals served as adults were served only in the civil system. Thirteen percent of the cohort received some of their mental health services as adults in the state-operated adult forensic mental health system due to criminal law involvement. This includes nine percent who received mental health services while they were inmates in state prisons. Twenty four of the 57 forensic clients received services as adults only in the forensic system. Diagnostic, demographic, and service history characteristics of the groups were compared to foster an early understanding of policy and programmatic issues related to movement from the child mental health system to the adult system. Baseline (1982) information was used to identify predictors of later service utilization.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号