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   39762篇
  免费   1619篇
  国内免费   14篇
  41395篇
  2020年   381篇
  2019年   435篇
  2018年   601篇
  2017年   606篇
  2016年   683篇
  2015年   506篇
  2014年   583篇
  2013年   2712篇
  2012年   1129篇
  2011年   1103篇
  2010年   692篇
  2009年   660篇
  2008年   995篇
  2007年   975篇
  2006年   862篇
  2005年   825篇
  2004年   769篇
  2003年   692篇
  2002年   729篇
  2001年   1281篇
  2000年   1234篇
  1999年   905篇
  1998年   408篇
  1997年   352篇
  1992年   873篇
  1991年   809篇
  1990年   828篇
  1989年   722篇
  1988年   721篇
  1987年   695篇
  1986年   719篇
  1985年   796篇
  1984年   602篇
  1983年   547篇
  1982年   376篇
  1981年   362篇
  1979年   692篇
  1978年   431篇
  1977年   421篇
  1976年   416篇
  1975年   588篇
  1974年   672篇
  1973年   720篇
  1972年   625篇
  1971年   585篇
  1970年   579篇
  1969年   566篇
  1968年   757篇
  1967年   671篇
  1966年   599篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
21.
22.
23.
24.
An electronic apparatus using infrared beams for monitoring the movements of individual bees under dark conditions is described. The searching behavior of workers in an arena was monitored over 2-h periods. Mean ambulatory velocity for one bee over a distance of 100 mm was 45.6±1.51 mm/sec (n=45). Thigmokinesis and temporal activity patterns are illustrated.  相似文献   
25.
26.
Four experiments were conducted to determine whether echoic memory plays a role in differences between good and poor readers. The first two experiments used a suffix procedure in which the subject is read a list of digits with either a tone control or the word go appended to the list. For lists that exceeded the length of the subjects memory span by one digit (i.e., that avoided ceiling effects), the poor readers showed a larger decrement in the suffix condition than did the good readers. The third experiment was directed at the question of whether the duration of echoic memory is different for good and poor readers. Children shadowed words presented to one ear at a rate determined to give 75-85% shadowing accuracy. The items presented to the nonattended ear were words and an occasional digit. At various intervals after the presentation of the digit, a light signaled that the subject was to cease shadowing and attempt to recall any digit that had occurred in the nonattended ear recently. Whereas good and poor readers recalled the digit equally if tested immediately after presentation, the poor readers showed a faster decline in recall of the digit as retention interval increased. A fourth experiment was conducted to determine whether the differences in echoic memory were specific to speech stimuli or occurred at a more basic level of aural persistence. Bursts of white noise were separated by 9-400 ms of silence and the subject was to say whether there were one or two sounds presented. There were no differences in detectability functions for good and poor readers.  相似文献   
27.
28.
The current study hypothesized that (1) hope would negatively predict burdensomeness, thwarted belongingness, and acquired capability to enact lethal injury; (2) hope would negatively predict suicidal ideation; and (3) the interpersonal suicide risk factors would predict suicidal ideation. Results indicated that hope negatively predicted burdensomeness and thwarted belongingness, but positively predicted acquired capability to enact suicide. Contrary to our second hypothesis, hope did not predict suicidal ideation, but interpersonal risk factors for suicide predicted suicidal ideation. Results are discussed in terms of implications for hope theory and Joiner's (2005) interpersonal risk factors for suicide, and for clinical practice.  相似文献   
29.
Self‐abandonment and self‐denial are, respectively, Catholic and hyper‐Calvinist analogues of each other. Roughly, each requires the surrendering of a person to God's will and providence through faith, hope, and love. Should the self‐abandoning/self‐denying individual accept his or her own damnation if that be God's will? This article, which is virtually alone in discussing the Catholic and Reformed Protestant traditions together, answers “No.” The unqualified self‐abandonment present in quietism and the radical self‐denial of Samuel Hopkins are perverse and irrational responses to the prospect of hell because they run counter to the Christian's deepest need to spend eternity with God. However, a qualified self‐abandonment is intellectually defensible and offers a viable Christian piety.  相似文献   
30.
A growing literature has observed a significant reduction in pain sensitivity among hypertensive animals and humans. It is uncertain whether a reduced sensitivity to pain can be observed in nonnotensive individuals who go on to develop high blood pressure. Blood pressure (BP) was reassessed in one hundred fifteen 19-year-old boys initially tested at age 14, when they were also presented with a pain stimulus (mechanical finger pressure). Hierarchical regression analyses indicated that information regarding pain tolerance improved prediction of changes in systolic and diastolic blood pressure beyond that afforded by differences in BP at age 14, parental history of hypertension, and body mass index. These analyses suggest that pain sensitivity may be associated with physiological processes involved in the development of sustained high blood pressure.  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