全文获取类型
收费全文 | 16094篇 |
免费 | 619篇 |
国内免费 | 4篇 |
专业分类
16717篇 |
出版年
2019年 | 213篇 |
2018年 | 258篇 |
2017年 | 219篇 |
2016年 | 257篇 |
2015年 | 169篇 |
2014年 | 261篇 |
2013年 | 1272篇 |
2012年 | 432篇 |
2011年 | 485篇 |
2010年 | 289篇 |
2009年 | 312篇 |
2008年 | 413篇 |
2007年 | 441篇 |
2006年 | 421篇 |
2005年 | 343篇 |
2004年 | 372篇 |
2003年 | 334篇 |
2002年 | 329篇 |
2001年 | 451篇 |
2000年 | 510篇 |
1999年 | 342篇 |
1998年 | 205篇 |
1997年 | 154篇 |
1996年 | 166篇 |
1995年 | 164篇 |
1992年 | 276篇 |
1991年 | 285篇 |
1990年 | 296篇 |
1989年 | 276篇 |
1988年 | 267篇 |
1987年 | 234篇 |
1986年 | 246篇 |
1985年 | 259篇 |
1984年 | 191篇 |
1983年 | 207篇 |
1982年 | 158篇 |
1980年 | 156篇 |
1979年 | 248篇 |
1978年 | 216篇 |
1977年 | 150篇 |
1975年 | 215篇 |
1974年 | 242篇 |
1973年 | 268篇 |
1972年 | 225篇 |
1971年 | 210篇 |
1970年 | 162篇 |
1969年 | 195篇 |
1968年 | 248篇 |
1967年 | 239篇 |
1966年 | 209篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
171.
A common criticism of iterative least squares estimates of communality is that method of initial estimation may influence stabilized values. As little systematic research on this topic has been performed, the criticism appears to be based on cumulated experience with empirical data sets. In the present paper, two studies are reported in which four types of initial estimate (unities, squared multiple correlations, highestr, and zeroes) and four levels of convergence criterion were employed using four widely available computer packages (BMDP, SAS, SPSS, and SOUPAC). The results suggest that initial estimates have no effect on stabilized communality estimates when a stringent criterion for convergence is used, whereas initial estimates appear to affect stabilized values employing rather gross convergence criteria. There were no differences among the four computer packages for matrices without Heywood cases. 相似文献
172.
173.
Fear of death and the concept of extended self 总被引:1,自引:0,他引:1
174.
Effects of presentation complexity on rapid-sequential reading 总被引:1,自引:0,他引:1
175.
176.
Hemispheric symmetry in contrast and orientation sensitivity 总被引:1,自引:0,他引:1
177.
Cross-language evidence for three factors in speech perception 总被引:4,自引:0,他引:4
178.
F Ficker 《Psychiatrie, Neurologie, und medizinische Psychologie》1985,37(9):548-553
The phases of a patient's struggle to come to terms with a malignant disease and impending death are illustrated by means of W. M. Diggelmann's book "Schatten--Tagebuch einer Krankheit" (Shadow--Diary of an Illness). Their expression, mutual influences and contents are documented by quotations. 相似文献
179.
180.
This project studied the effects of weather variables and size of the population on minor and major violence rates within six prisons in the Kingston, Ontario, Canada area from January, 1980 through December, 1983. While weather variables have been studied in relation to mood changes within the general population, this study was the first to analyze the impact of weather variables on rates of violence within the prison setting using forward inclusion multiple regression. Analysis showed that population size consistently appeared positively correlated with assaults on other inmates among the male medium-security prisoners during the summer months. In the summer months, temperature tended to be positively related to some minor kinds of offenses, but in the winter months the relationship was negative. Humidity, rain, sunshine hours, snow, and snow on the ground were not consistently related to incidences of minor and major violence. Indices of geomagnetic disturbances had statistically significant inverse relationships with attempted suicide/self-inflicted injury rates among the male prisoners during the summer months. Over 12 months, wind was generally negatively correlated with incidences of major and minor violence among the male inmates. For 6-mo. periods, wind was generally positively correlated with violence rates during the winter months and negatively correlated during the summer months among the male inmates. The findings relating weather variables to violence rates in the women's prison were consistently in opposition to those found for male prisoners during the 4-yr. period. 相似文献