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   53316篇
  免费   2165篇
  国内免费   31篇
  2020年   594篇
  2019年   767篇
  2018年   1091篇
  2017年   1105篇
  2016年   1150篇
  2015年   773篇
  2014年   940篇
  2013年   4659篇
  2012年   1697篇
  2011年   1850篇
  2010年   1082篇
  2009年   1117篇
  2008年   1691篇
  2007年   1668篇
  2006年   1464篇
  2005年   1319篇
  2004年   1291篇
  2003年   1179篇
  2002年   1222篇
  2001年   1771篇
  2000年   1669篇
  1999年   1289篇
  1998年   679篇
  1997年   585篇
  1996年   529篇
  1995年   532篇
  1994年   509篇
  1993年   527篇
  1992年   1022篇
  1991年   971篇
  1990年   952篇
  1989年   856篇
  1988年   821篇
  1987年   811篇
  1986年   818篇
  1985年   872篇
  1984年   679篇
  1983年   592篇
  1982年   481篇
  1979年   659篇
  1978年   496篇
  1976年   455篇
  1975年   598篇
  1974年   635篇
  1973年   606篇
  1972年   545篇
  1971年   478篇
  1968年   545篇
  1967年   546篇
  1966年   483篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
891.
892.
893.
894.
895.
896.
Taste sensitivity for sodium chloride in solution and sensitivity and preference for sodium chloride in bread were measured in 14 male patients undergoing hemodialysis. There was an increase in sensitivity to salt taste following dialysis only when assessed using the bread samples. Patients on a lower sodium diet were more sensitive to salt taste in bread. Although the taste changes were not related to the decreases in serum sodium or to copper, greater increases in sensitivity were related to greater increases in serum zinc during dialysis.  相似文献   
897.
For 40 males who smoked 20 cigarettes a day titratable acidity of the urine was significantly correlated with nicotine/cotinine excretion at several sample intervals, as was urinary pH, but not urinary acidity and daily cigarette consumption or serum COHB.  相似文献   
898.
6 adult subjects (3 men, 3 women) produced highly similar spontaneous speech utterances in quiet and with 90-dB SPL white noise. The frequency of occurrence of perceptual judgments of primary stressing in an utterance was not affected by the masking noise. This finding supplements our previous report that variability for stress production of fundamental frequency (fo) during spontaneous speech was preserved under short-term auditory disruption. Also, it adds further support to the contention that fo is under open-loop regulation.  相似文献   
899.
Children's perception of parental exercise: influence of sex and age   总被引:1,自引:0,他引:1  
The purpose of the study was to document children's perception of parental exercise, relating these perceptions to (1) the self-reported parents' habits of exercise, and (2) the children's own activity patterns. The subjects were 198 students of both sexes, aged 12 to 14 yr. and enrolled in school Grades 7 to 9. A standard questionnaire assessed their perceptions of parental and personal physical activity. Both parents of each subject also reported their respective levels of habitual physical activity. Congruence between the children's perceptions and the self-reported exercise habits of the opposite-sex parent differed for boys and girls, increasing for boys and decreasing for girls between Grades 7 and 9. No significant associations were observed between the children's perception of parental exercise patterns and their own like habits. This suggests that during adolescence parental influences are minimized by other factors, personal or environmental.  相似文献   
900.
The lexical decision task has been employed to investigate the effects of semantic context on word recognition. A frequent finding from the task is that “word” responses are slower when the target is preceded by an unrelated word than when it is preceded by a neutral stimulus. This inhibition effect has been interpreted as indicating that the unrelated prime interferes with word-recognition processes operating on the target. In three experiments, the effects of unrelated primes were compared for a lexical decision and word naming task. Although large inhibition effects were found for the lexical decision task in all experiments, no inhibition effects were observed for the naming task. The results are interpreted as demonstrating that inhibition effects in the lexical decision task are not on recognition processes; rather they are located at processes operating after recognition of the target has occurred.  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