全文获取类型
收费全文 | 2515篇 |
免费 | 273篇 |
国内免费 | 1篇 |
专业分类
2789篇 |
出版年
2024年 | 3篇 |
2023年 | 42篇 |
2022年 | 15篇 |
2021年 | 21篇 |
2020年 | 121篇 |
2019年 | 53篇 |
2018年 | 60篇 |
2017年 | 118篇 |
2016年 | 142篇 |
2015年 | 107篇 |
2014年 | 101篇 |
2013年 | 475篇 |
2012年 | 130篇 |
2011年 | 74篇 |
2010年 | 81篇 |
2009年 | 122篇 |
2008年 | 106篇 |
2007年 | 85篇 |
2006年 | 80篇 |
2005年 | 65篇 |
2004年 | 54篇 |
2003年 | 51篇 |
2002年 | 48篇 |
2001年 | 22篇 |
2000年 | 24篇 |
1999年 | 25篇 |
1998年 | 24篇 |
1997年 | 18篇 |
1996年 | 49篇 |
1995年 | 44篇 |
1994年 | 29篇 |
1993年 | 41篇 |
1992年 | 44篇 |
1991年 | 39篇 |
1990年 | 36篇 |
1989年 | 28篇 |
1988年 | 22篇 |
1987年 | 18篇 |
1986年 | 19篇 |
1985年 | 15篇 |
1984年 | 9篇 |
1983年 | 9篇 |
1982年 | 13篇 |
1981年 | 11篇 |
1980年 | 18篇 |
1979年 | 15篇 |
1978年 | 22篇 |
1977年 | 26篇 |
1975年 | 7篇 |
1971年 | 3篇 |
排序方式: 共有2789条查询结果,搜索用时 7 毫秒
121.
Sagrestano LM Feldman P Rini CK Woo G Dunkel-Schetter C 《American journal of community psychology》1999,27(6):869-898
Data from two multi-ethnic prospective studies of African American, Latina, and non-Hispanic White pregnant women were used to examine the influence of contextual factors on social support processes during pregnancy. Multiple types of support (perceived support, received support, support satisfaction, network support) and sources of support (baby's father, family, friends) were assessed. The role of ethnicity in social support was examined after controlling for the contribution of related contextual factors (SES, marital status, age, parity, employment) to these processes. The impact of ethnicity and related contextual factors differed across sources of social support. Ethnic differences in support from family and friends, but not from the baby's father, emerged. However, marital status was a consistent predictor of support from the baby's father, and SES was a consistent predictor of support from friends. Overall, the findings of two studies suggest that although ethnicity is associated with support from friends and family, other contextual factors, such as marital status and SES, influence support processes during pregnancy. 相似文献
122.
Sequence-Specific Impairment of Memory Formation by NCAM Antisense Oligonucleotides 总被引:13,自引:0,他引:13 下载免费PDF全文
Radmila Mileusnic Christine Lancashire Steven P.R. Rose 《Learning & memory (Cold Spring Harbor, N.Y.)》1999,6(2):120-127
The functional role of NCAM gene expression in memory formation was studied in the one-trial passive avoidance task in day-old chicks by pretraining injections of one of three different 18-mer end-protected oligonucleotides corresponding to positions 190-, 207-, and 332- of the NCAM Ig1 domain. Twenty-four-hour-old chicks were trained by pecking at a bitter-tasting bead and tested for avoidance 30 min, 3, 8, or 24 hr later. Memory retention was significantly reduced only in the group of animals injected with the NCAM antisense corresponding to position 207- (AS-ODN-207), and only if given twice, both immediately after hatching and 12 hr before training. This antisense was without effect on the general behavior of the chicks, training or acquisition, and did not produce observable neurotoxic damage. Under such conditions amnesia was evident by 3 hr after training and lasted until at least 24 hr after training. The two other tested oligonucleotides were without behavioral effect. To control for nonsequence-specific effects of AS-ODN-207, brains from injected and trained animals were processed for Western blotting and probed using anti-NCAM, anti-L1, and anti-actin antibodies. NCAM antisense corresponding to position 207- significantly reduced the level of NCAM, whereas the level of L1 and actin remained unchanged. These results confirm our earlier conclusion that NCAM is necessary for longer term memory retention. 相似文献
123.
124.
Joseph S. Lalli Timothy R. Vollmer Patrick R. Progar Carrie Wright John Borrero Dency Daniel Christine Hoffner Barthold Kathy Tocco William May 《Journal of applied behavior analysis》1999,32(3):285-296
We compared the effects of reinforcing compliance with either positive reinforcement (edible items) or negative reinforcement (a break) on 5 participants' escape-maintained problem behavior. Both procedures were assessed with or without extinction. Results showed that compliance was higher and problem behavior was lower for all participants when compliance produced an edible item rather than a break. Treatment gains were achieved without the use of extinction. Results are discussed regarding the use of positive reinforcement to treat escape behavior. 相似文献
125.
Identification With All Humanity (IWAH) relates to higher levels of concern and supportive behavior toward the disadvantaged, stronger endorsement of human rights, and stronger responses in favor of global harmony. So far, IWAH has been conceptualized as a one‐dimensional construct describing the degree with which one identifies with all humans as a superordinate ingroup. However, recent group identification models suggest a multi‐dimensional model to provide a more differentiated approach toward the understanding of the highest level of social identification. Using principal axis (Study 1) and confirmatory (Study 2) factor analyses, we suggest that IWAH sub‐divides into two dimensions—global self‐definition and global self‐investment. Study 2 revealed that global self‐investment was a stronger predictor for both convergent measures (e.g., social dominance orientation and authoritarianism) and behavioral intentions than global self‐definition. Finally, in Study 3, we manipulated IWAH to test its causal effect on donation behavior. Participants in the experimental condition, compared with the control condition, showed higher global self‐investment, which in turn predicted greater giving to global charity. These findings suggest that two dimensions with different behavioral outcomes underlie IWAH. 相似文献
126.
Carmen Knudson-Martin PhD 《Contemporary Family Therapy》1992,14(3):241-258
This study uses an interpretive interview method to examine the micro-processes of generational continuity and change among a group of social activists. Boszormenyi-Nagy's theory of responsibility between generations, alternative models outside the family, and choice are used to explain the instances of change. Implications for research and practice are addressed. 相似文献
127.
Marilyn J. Mason PhD 《Contemporary Family Therapy》1987,9(1-2):90-105
This paper describes the process in which families participate in a wilderness experience. Metaphors such as climbing or paddling a canoe are translated into daily living patterns to deepen individual and family self-knowledge, self-esteem, and intimacy. 相似文献
128.
129.
The experiences of 44 group sexual assault victims (multiple offenders, one victim) were compared with 44 individual sexual assault victims (one offender, one victim). Sexual assaults included various degrees of sexual victimization ranging from verbal coercion to rape. Participants were located from among a national sample of 3,187 college women. Group sexual assaults, compared to individual sexual assaults, were in general more violent, involved greater resistance from the victims, and were more likely to be perpetrated by strangers or relatives and to involve an experience which met the legal definition of rape. Group sexual assaults were less likely to involve multiple episodes by the same offender(s). Group sexual assault victims were more likely than individual sexual assault victims to seek police and crisis services, to have contemplated suicide, and to have sought therapy postassault. Despite these differences, the two groups were similar in the amount of drinking and drug use during the assault and their scores on standardized measures of psychological symptoms. 相似文献
130.