全文获取类型
收费全文 | 40863篇 |
免费 | 1649篇 |
国内免费 | 28篇 |
出版年
2020年 | 454篇 |
2019年 | 467篇 |
2018年 | 852篇 |
2017年 | 784篇 |
2016年 | 887篇 |
2015年 | 602篇 |
2014年 | 669篇 |
2013年 | 2806篇 |
2012年 | 1369篇 |
2011年 | 1489篇 |
2010年 | 720篇 |
2009年 | 781篇 |
2008年 | 1060篇 |
2007年 | 1033篇 |
2006年 | 942篇 |
2005年 | 2008篇 |
2004年 | 1381篇 |
2003年 | 1154篇 |
2002年 | 821篇 |
2001年 | 1418篇 |
2000年 | 1384篇 |
1999年 | 983篇 |
1998年 | 405篇 |
1997年 | 372篇 |
1993年 | 318篇 |
1992年 | 818篇 |
1991年 | 729篇 |
1990年 | 816篇 |
1989年 | 731篇 |
1988年 | 686篇 |
1987年 | 647篇 |
1986年 | 690篇 |
1985年 | 727篇 |
1984年 | 555篇 |
1983年 | 478篇 |
1982年 | 338篇 |
1979年 | 522篇 |
1978年 | 410篇 |
1977年 | 327篇 |
1976年 | 323篇 |
1975年 | 485篇 |
1974年 | 588篇 |
1973年 | 543篇 |
1972年 | 481篇 |
1971年 | 402篇 |
1970年 | 357篇 |
1969年 | 425篇 |
1968年 | 477篇 |
1967年 | 414篇 |
1966年 | 450篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
881.
W Kallenbach G Küllertz G Fischer 《Psychiatrie, Neurologie, und medizinische Psychologie》1984,36(5):295-302
The investigation of enzyme activity in cerebrospinal fluid has been without relevant results for laboratories analysing spinal fluid. For neurochemical purposes, it is interesting that the Substance P is convered by Depeptidyl-aminopeptidase IV (DP IV), liberating dipeptides. The hydrolysis of nitroanilids of the form Xaa-Pro-NHNp in cerebrospinal fluid was analysed using them as peptidases substrates. Finally a method for measuring the activity was proposed. 相似文献
882.
E Müller A Schapowahl A Seel?nder 《Psychiatrie, Neurologie, und medizinische Psychologie》1984,36(8):480-488
The somatic and psychosocial development of 80 subjects with manifest affective-phasic psychoses is studied retrospectively and compared with that of an identically sized control group consisting of neuropsychiatrically healthy subjects. Statistically significant differences were found particularly in the answers to questions dealing with social situation and social adaptability. Achievement at school and vocational qualifications were lower among the parents of the patients than among those of the healthy subjects. Characteristic features of the patients' childhood and adolescence were transient depression, often for no apparent cause, and maladaption, and vocational wishes were fulfilled less often than among the controls. The patients experienced greater difficulty in settling in to a new group due to their contact difficulties. 相似文献
883.
T Krause W P Pankau A Wagner J L?ssner 《Psychiatrie, Neurologie, und medizinische Psychologie》1984,36(9):545-550
By 48 patients with Wilson's disease the brainstem acoustic evoked potentials were stated. There were 35 pathological findings (73%), 13 were normal (27%). The waves, determined by the middle and upper brainstem (Pons and Mesencephalon) showed most of all pathological changes. Those patients with forms of Wilson's disease called Pseudoskelerose and Pseudoparkinson showed the most pathological findings. But one could watch these findings by about 30% of patients in preclinical stage. This method can possibly be used for early detection of disorders of brainstem functions and in the same way it can be used for control of treatment by patients in preclinical stage. 相似文献
884.
Distraction and coping with pain 总被引:7,自引:0,他引:7
885.
886.
The effects of tobacco smoking on responses to electrical stimulation were studied according to a Method of Limits (ML) threshold analysis and a Sensory Decision Theory (SDT) analysis. For the ML procedure, Detection Threshold (DT), Pain Threshold (PT) and Tolerance Level (TL) measures were obtained. For the SDT procedure, nonparametric estimates of capacity to discriminate between stimulus intensities (P(A)) and response criterion (B) were calculated. There was no main effect of tobacco smoking on responses to electrical stimulation. Males had consistently higher ML thresholds than females in both the NS and S condition. Males also tended to increase in DT and PT after smoking. From a comparison between the effects of smoking on ML and SDT measures it was suggested that PT is related mainly to sensory factors and TL to response factors. 相似文献
887.
Asymmetric neural control systems in human self-regulation 总被引:15,自引:0,他引:15
888.
Prolonged deprivation and future orientation (FO) were studied in 200 Indian and Nepalese students of 14–16 and 18–20 years with verbal measures. In both cultures low deprived subjects were significantly more future-oriented. In the development of FO both age and deprivation were significant with experiential aspect of socialization exerting greater influence than physico-economic deprivation. 相似文献
889.
890.
Daniel S. Lee Julie A. Cederbaum Jordan P. Davis Michael S. Hurlburt Ferol E. Mennen 《Family process》2023,62(1):254-271
Maternal and adolescent depression are challenges that often co-occur. Many studies have drawn bivariate associations between maternal depressive symptoms, adolescent depressive symptoms, and family conflict, but few have examined reciprocal effects. Even among extant studies, there is a lack of clarity related to directionality of influence. Three competing theoretical models may explain the relationship between maternal depressive symptoms, adolescent depressive symptoms, and family conflict, and these processes may differ by adolescents’ sex. Using three time points of data from 187 diverse mother-adolescent dyads, we fit a taxonomy of autoregressive cross-lagged structural equation models to simultaneously evaluate the competing theoretical models and also examine differences by sex using multiple-group analyses. Results indicate a symptom-driven model whereby adolescent depressive symptoms predicted increases in family conflict. Sex differences were also found. For males, but not females, greater adolescent depressive symptoms predicted subsequent increases in maternal depressive symptoms, which then predicted lower family conflict—possibly indicating maternal disengagement/withdrawal. Our findings suggest addressing adolescent depressive symptoms in order to prevent family conflict and that distinctive targets for the prevention/intervention of family conflict should account for differences by adolescents’ sex. 相似文献