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   14131篇
  免费   578篇
  国内免费   3篇
  2020年   162篇
  2019年   194篇
  2018年   270篇
  2017年   301篇
  2016年   295篇
  2015年   226篇
  2014年   296篇
  2013年   1589篇
  2012年   524篇
  2011年   550篇
  2010年   343篇
  2009年   355篇
  2008年   527篇
  2007年   491篇
  2006年   468篇
  2005年   469篇
  2004年   474篇
  2003年   452篇
  2002年   493篇
  2001年   261篇
  2000年   219篇
  1999年   228篇
  1998年   233篇
  1997年   220篇
  1996年   181篇
  1995年   184篇
  1994年   174篇
  1993年   193篇
  1992年   192篇
  1991年   152篇
  1990年   155篇
  1989年   145篇
  1988年   136篇
  1987年   144篇
  1986年   131篇
  1985年   158篇
  1984年   200篇
  1983年   203篇
  1982年   199篇
  1981年   186篇
  1980年   155篇
  1979年   141篇
  1978年   190篇
  1977年   164篇
  1976年   175篇
  1975年   154篇
  1974年   166篇
  1973年   115篇
  1972年   93篇
  1968年   90篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
83.
Two dogs received a single paired classical conditioning trial, with tone CS and 12 mA shock US. Both dogs then showed a conditioned blood pressure increase in response to the nonreinforced CS, which extinguished with additional nonreinforced presentations. The CR showed spontaneous recovery four days later, but reextinguished with additional nonreinforced presentations. The results were interpreted as not supporting Eysenck's theory of "incubation" following one-trial aversive conditioning.  相似文献   
84.
Simultaneous prompting (a type of antecedent prompt and test procedure) and constant time delay were compared with four students with moderate mental retardation learning expressive sight words. A parallel treatments design across word sets and replicated across students was used. For acquisition, the simultaneous prompting procedures required fewer trials, sessions, and training time to criterion and resulted in fewer student errors during daily probe and training sessions. However, maintenance data indicated mixed results across the two procedures. Reliability data (both dependent and independent variables) revealed no differences between the two procedures in terms of the teacher's accuracy in recording student responses and implementing each procedure. Future research issues are discussed.  相似文献   
85.
Genetic counselors have participated in the Michigan Newborn Screening Program on a contractual basis since 1988. Their role includes newborn screening education and training, newborn nursery site visits, and monitoring newborn screening in hospitals. Their impact has been to improve the quality of newborn screening services by reducing errors and increasing completion of data fields on newborn screening cards, improving hospital nursery cooperation and problem solving, and enhancing health department response to specific problems.  相似文献   
86.
A tether system has been developed for continuous monitoring of blood pressure in the micropig. The micropig is a suitable model for blood-pressure research because of the similarity of its cardiovascular system to that of humans and because of its sensitivity to high sodium intake. The system consists of a metal boom, attached via a universal joint to a wall 6 ft above floor level, that extends horizontally to the center of the enclosure. A fluid and electronic swivel affixed to the boom is connected to a flexible, hollow, metal tether that descends to a vest worn by the micropig. The vest contains a pressure transducer to which an indwelling arterial catheter is connected via a stopcock. The transducer cable and an infusion line ascend through the interior of the tether to the swivel. The system remains in equilibrium through a system of pulleys and counterweights. Continuous, 24-h recording shows a diurnal variation characterized by higher heart rate but lower blood pressure during the day than at night. The system has been found to be effective for continuous studies over intervals of a month or more.  相似文献   
87.
88.
The negative-tilt preparation that has been reported since the late seventies is a specific form of Pavlovian conditioning that is of scientific interest and has potential applications. In this paper I reflect on the usefulness, to the development of this preparation, of two approaches to Pavlovian conditioning. One approach is the older S-R learning, stimulus-substitution paradigm exemplified by learning texts of the sixties. The other is the modern, Tolman-like view, according to which the phenomenon of Pavlovian conditioning is “now described as the learning of relations among events so as to allow the organism to represent its environment.” The three assumptions encapsulated by this approach are: (a) that only CS-US contingency relations are learned; (b) that teleological modes of explanations are adequate; (c) that the representational theory of knowledge is sound. Concerning Pavlovian conditioning in general, questions been raised in the literature for all three assumptions; they have not been adequately answered. Regarding the specific problem of developing the human Pavlovian heart-ratedecelerative conditioning with negative tilt as the US, I suggest that the cognitive approach has been much less helpful than the older, S-R, stimulus-substitution paradigm. Nevertheless, other literature clearly indicates that the cognitive, S-S approach has generated considerable interest and research, especially in preparations like the conditioned emotional response (CER), which are CS-IR ones in the sense that the effects on the CR are assessed indirectly through measuring an indicator or instrumental response (IR). Finally, even in CS-CR preparations like human GSR conditioning, it is important to study the cognitive, S-S learning process through using such dependent variables as continuously assessed subjective CS-US contingency.  相似文献   
89.
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