全文获取类型
收费全文 | 608333篇 |
免费 | 55258篇 |
国内免费 | 326篇 |
专业分类
663917篇 |
出版年
2018年 | 9872篇 |
2017年 | 9563篇 |
2016年 | 9624篇 |
2015年 | 7925篇 |
2014年 | 9423篇 |
2013年 | 14016篇 |
2012年 | 17150篇 |
2011年 | 21952篇 |
2010年 | 15776篇 |
2009年 | 14701篇 |
2008年 | 19236篇 |
2007年 | 21335篇 |
2006年 | 14458篇 |
2005年 | 14478篇 |
2004年 | 14404篇 |
2003年 | 14343篇 |
2002年 | 14126篇 |
2001年 | 23772篇 |
2000年 | 24160篇 |
1999年 | 18818篇 |
1998年 | 6596篇 |
1997年 | 6936篇 |
1996年 | 6483篇 |
1995年 | 6065篇 |
1993年 | 6053篇 |
1992年 | 16279篇 |
1991年 | 16194篇 |
1990年 | 16027篇 |
1989年 | 15822篇 |
1988年 | 14861篇 |
1987年 | 14008篇 |
1986年 | 12996篇 |
1985年 | 13488篇 |
1984年 | 11148篇 |
1983年 | 9599篇 |
1982年 | 7172篇 |
1981年 | 6405篇 |
1980年 | 6070篇 |
1979年 | 10682篇 |
1978年 | 8338篇 |
1977年 | 7756篇 |
1976年 | 7314篇 |
1975年 | 8154篇 |
1974年 | 9020篇 |
1973年 | 8851篇 |
1972年 | 8730篇 |
1971年 | 7923篇 |
1970年 | 6543篇 |
1969年 | 6446篇 |
1968年 | 6019篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
I. N. Konareva 《Neurophysiology》2006,38(3):201-208
Modifications of different EEG rhythms induced by a single neurofeedback session (by the EEG characteristics) directed toward
an increase in the ratio of the spectral powers (SPs) of the α vs θ oscillations were compared with the psychological characteristics of the tested subjects (the group included 30 persons).
A generally accepted neurofeedback technique was used; the intensity of acoustic white noise served as the feedback signal.
EEG potentials were recorded from the C3 and C4 leads. Psychological testing was carried out using Eysenck’s (EPQ), Rusalov’s
(OST), and (16 PF) questionnaires. The directions of changes in the SPs of EEG frequency components were found to significantly
correlate with some individuality-related peculiarities of the tested subjects. The SP of the δ rhythm correlated with the
EPQ scale “neuroticism,” OST scale “social plasticity,” and 16 PF factors H (“parmia”), I (“premsia”), and Q3 (“self-control of behavior”). The SP of the θ component demonstrated correlations with the OST scales “ergisity,” “plasticity,”
and “social temp” and with 16 PF factors M (“autia”), Q4 (“frustration”), and Q1 (“exvia”). The SP of the α rhythm correlated with 16 PF factors Q3 (“self-control of behavior”), G (“strength of superEgo”), O (“hypothymia”), L (“protension”), and N (“shrewdness”). The SP
of the β rhythm correlated with the OST scale “emotionality,” while that of the γ rhythm showed correlations with the 16 PF
indices L (“protension”) and M (“autia”). Changes in the ratio of the α vs θ SPs correlated with the EPQ scale “neuroticism.” Thus, our data confirm the statement that a high individual variability
of the results of a single (first in the series) neurofeedback session is to a great extent related to peculiarities of the
individual psychological pattern of the subject.
Neirofiziologiya/Neurophysiology, Vol. 38, No. 3, pp. 239–247, May–June, 2006. 相似文献
993.
A study was made of the dose-time relationship during chromatin degradation in white blood cells of non-irradiated and irradiated rats. There was a linear increase in the release of PDN from leukocytes 1,2 and 3 days after irradiation (1-3 Gy) followed by the deceleration of the chromatin degradation at doses exceeding 3 Gy. 相似文献
994.
Dealing with patients'' sex-related complaints is uncomfortable for many physicians. It can become more comfortable if the physician learns to apply his or her clinical knowledge of sexuality in combination with specific interpersonal interviewing skills. The level of comfort can be increased if the physician accepts his or her professional limitations in providing therapy and knows what other sources of care are available. 相似文献
995.
V A Tret'iakov G P Chervonskaia Z M Andreeva B D Bychenko L L Mironova 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1987,(6):11-15
The biological activity of the filtrates of 29 C. difficile strains was studied in vivo (suckling white mice) and in vitro (cell cultures of different species and origin). The action of the filtrates on the experimental models in vivo was evaluated from the cytotoxic effect index, while in vitro the intensity of the cytotoxic effect was evaluated from the percentage of dead cells in the monolayer. The results of the comparative determination of toxicity characteristics in vivo and in vitro demonstrated that cell cultures were more sensitive experimental models than suckling white mice. The use of cell cultures permitted the quantitative evaluation of the cytotoxic activity of the filtrates under study, as well as the detection of their cell-directed action at minimal concentrations. 相似文献
996.
J C Lambert G Vallette G E Seralini R Vranckx E Nunez C Stora 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1986,302(9):353-358
Data are presented which indicate a possible action of alpha-fetoprotein (AFP) on female germinal cells. The in vitro maturation of mature mice oocytes was significantly inhibited when mouse AFP replaced albumin in the culture medium. In addition, the degenerative aspect of oocytes cultured with AFP seemed to indicate that this me?otic inhibition was caused by a premature degeneration of oocytes rather than by a blockage at a specific stage of maturation. Thus AFP, perhaps through its ligands, may play a role in the reduction of germinal cells during fetal and immediate post-natal life rather than in the arrest of me?osis at the diplotene stage. 相似文献
997.
998.
999.
1000.