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   45492篇
  免费   1634篇
  国内免费   20篇
  47146篇
  2019年   484篇
  2018年   635篇
  2017年   709篇
  2016年   775篇
  2015年   589篇
  2014年   661篇
  2013年   3450篇
  2012年   1194篇
  2011年   1231篇
  2010年   768篇
  2009年   760篇
  2008年   1065篇
  2007年   1055篇
  2006年   916篇
  2005年   883篇
  2004年   829篇
  2003年   820篇
  2002年   857篇
  2001年   1342篇
  2000年   1276篇
  1999年   949篇
  1998年   444篇
  1997年   414篇
  1992年   860篇
  1991年   848篇
  1990年   845篇
  1989年   814篇
  1988年   791篇
  1987年   752篇
  1986年   796篇
  1985年   845篇
  1984年   687篇
  1983年   621篇
  1982年   463篇
  1981年   507篇
  1980年   415篇
  1979年   758篇
  1978年   550篇
  1977年   485篇
  1976年   452篇
  1975年   660篇
  1974年   787篇
  1973年   816篇
  1972年   668篇
  1971年   643篇
  1970年   618篇
  1969年   619篇
  1968年   789篇
  1967年   728篇
  1966年   692篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Visual acuity for the detection of gratings at four orientations was measured for groups of ten boys and ten girls aged five to seven years, from the following four populations: Scots in Glasgow, Pakistanis in Glasgow, Gaels in Stornoway (Outer Hebrides) and East Anglians in Littleport (Cambridgeshire fenlands). The Glaswegians, both Scottish and Pakistani, showed the normal pattern of anisotropy, with poorest acuity for oblique orientations; the East Anglians showed no significant anisotropy; while the Gaels were unusual in showing poorest horizontal acuity. A group of fourteen Pakistani children in Stornoway differed slightly from a matched group of Gaels. The group differences bore little relation to the visual environments, and were probably due to genetic or cultural factors. The relatively poor horizontal acuity of the Gaels was not correlated with astigmatism. Sex differences were also found, with the boys showing higher mean acuity and a higher ratio between vertical and oblique acuity.  相似文献   
82.
The purpose of this study was to determine the effects of Type A behavior and family history of hypertension on cardiovascular reactivity to mental stress in a group of employed black women. Measures of heart rate and of systolic blood pressure (SBP) and diastolic blood pressure (DBP) were taken at rest, during a mental arithmetic task, and during the Type A Structured Interview (SI). Results indicated that the Type A behavior pattern was associated with SBP and DBP hyperresponsivity during the SI but not during mental arithmetic. Additionally, certain speech components of the Type A pattern, as well as features of the potential-for-hostility component, were also related to cardiovascular responses during the SI. Family history of hypertension did not influence the cardiovascular parameters either alone or in combination with Type A behavior. The results suggest that many of the cardiovascular response characteristics of the Type A pattern that have been observed in predominantly white samples also hold true for blacks. Replication of these findings with other subgroups of blacks, such as young females and middle-aged males, will help document the generality of these findings within the black population.  相似文献   
83.
84.
85.
86.
87.
88.
89.
90.
Recidivism data derived from various sources over a follow-up period of 1–11 yr, provided the basis for appraising the effectiveness of a comprehensive cognitive-behavioral treatment program for familial and nonfamilial child molesters. Unofficial records held by police and Children's Aid Societies proved to be the best data for estimating recidivism. These data revealed increases in recidivism with longer follow-up periods, but there were consistent advantages for the treated over the untreated patients. Men who had sexually abused the daughters of other people demonstrated the clearest treatment benefits. The younger offenders and those who had engaged in genital-genital contact with their victims were more likely to reoffend even if they were treated. Contrary to the expectations of behavior therapists, indices of deviant sexual preferences did not predict outcome.  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