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   340篇
  免费   2篇
  342篇
  2022年   10篇
  2021年   11篇
  2020年   6篇
  2019年   15篇
  2018年   10篇
  2017年   14篇
  2016年   13篇
  2015年   6篇
  2014年   8篇
  2013年   26篇
  2012年   5篇
  2011年   9篇
  2010年   7篇
  2009年   8篇
  2008年   3篇
  2007年   6篇
  2005年   6篇
  2004年   6篇
  2003年   7篇
  1995年   4篇
  1994年   4篇
  1993年   4篇
  1990年   5篇
  1989年   8篇
  1987年   2篇
  1983年   3篇
  1982年   5篇
  1981年   4篇
  1978年   2篇
  1977年   2篇
  1976年   2篇
  1975年   2篇
  1974年   4篇
  1973年   6篇
  1972年   3篇
  1970年   7篇
  1969年   3篇
  1968年   4篇
  1967年   7篇
  1966年   6篇
  1965年   9篇
  1964年   3篇
  1963年   6篇
  1962年   4篇
  1961年   10篇
  1960年   6篇
  1958年   7篇
  1957年   4篇
  1956年   3篇
  1955年   6篇
排序方式: 共有342条查询结果,搜索用时 15 毫秒
81.
J. Woleński 《Studia Logica》1990,49(2):273-282
This paper describes and compares the first step in modern semantic theory for deontic logic which appeared in works of Stig Kanger, Jaakko Hintikka, Richard Montague and Saul Kripke in late 50s and early 60s. Moreover, some further developments as well as systematizations are also noted.  相似文献   
82.
83.
An increasing number of drugs removed from the market because of unacceptable toxicity raises concerns regarding preapproval testing of drug safety. In the present paper it is postulated that the non-inferiority type of trial should be abandoned in favor of the superiority trial with active controls and less stringent (p<0.1, both for efficacy and toxicity) statistics. This approach will increase sensitivity of detection of drug-induced adverse effects at the expense of increasing false positive results regarding the difference in efficacy between the tested and reference drug. Such a move will increase the protection of future patients. In addition, the proposed design is far more acceptable from the clinical (e.g. no need to specify the statistically expected “unimportant” number of deaths) and ethical points of view, as well as being favored by the strong incentive of involved parties. In the second part of this paper arguments are presented in favor of the hypothesis that placebo (still used in some superiority trials) does not induce adverse effects. The assertion that placebo may induce adverse effects is probably biased by the nature of the clinical experiment. Such a conclusion is supported by studies indicating that placebo-induced adverse effects are disease — and treatment — specific. The modification of clinical trials according to the proposed changes may increase the trials’ sensitivity at detecting adverse effects of drugs. A lecture on the subject of this paper was presented at the 6th International Bioethics Conference on the subject of ‘The Responsible Conduct of Basic and Clinical Research’, held in Warsaw, Poland, 3–4 June 2005.  相似文献   
84.
The Lambek calculus introduced in Lambek [6] is a strengthening of the type reduction calculus of Ajdukiewicz [1]. We study Associative Lambek Calculus L in Gentzen style axiomatization enriched with a finite set Γ of nonlogical axioms, denoted by L(Γ).It is known that finite axiomatic extensions of Associative Lambek Calculus generate all recursively enumerable languages (see Buszkowski [2]). Then we confine nonlogical axioms to sequents of the form pq, where p and q are atomic types. For calculus L(Γ) we prove interpolation lemma (modifying the Roorda proof for L [10]) and the binary reduction lemma (using the Pentus method [9] with modification from [3]). In consequence we obtain the weak equivalence of the Context-Free Grammars and grammars based on L(Γ).  相似文献   
85.
86.
87.
88.
89.
Phenomena observed during treatment with neuroleptics were clinically measured in an attempt to determine the difference in vulnerability of the two hemispheres and the relation between this difference and schizophrenic diseases. In the group of systematic schizophrenias the increase in tonus was significantly higher in the dominant hemisphere. This finding is considered a verification of the nosological hypothesis of schizophrenias.  相似文献   
90.
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