全文获取类型
收费全文 | 64281篇 |
免费 | 2460篇 |
国内免费 | 31篇 |
专业分类
66772篇 |
出版年
2020年 | 682篇 |
2019年 | 890篇 |
2018年 | 1201篇 |
2017年 | 1318篇 |
2016年 | 1278篇 |
2015年 | 921篇 |
2014年 | 1091篇 |
2013年 | 5050篇 |
2012年 | 1962篇 |
2011年 | 2068篇 |
2010年 | 1336篇 |
2009年 | 1313篇 |
2008年 | 1867篇 |
2007年 | 1833篇 |
2006年 | 1654篇 |
2005年 | 1444篇 |
2004年 | 1349篇 |
2003年 | 1346篇 |
2002年 | 1297篇 |
2001年 | 2107篇 |
2000年 | 2039篇 |
1999年 | 1550篇 |
1998年 | 696篇 |
1997年 | 633篇 |
1996年 | 605篇 |
1994年 | 606篇 |
1992年 | 1309篇 |
1991年 | 1204篇 |
1990年 | 1223篇 |
1989年 | 1107篇 |
1988年 | 1108篇 |
1987年 | 1069篇 |
1986年 | 1061篇 |
1985年 | 1068篇 |
1984年 | 905篇 |
1983年 | 791篇 |
1982年 | 603篇 |
1979年 | 957篇 |
1978年 | 702篇 |
1977年 | 631篇 |
1975年 | 797篇 |
1974年 | 851篇 |
1973年 | 938篇 |
1972年 | 741篇 |
1971年 | 670篇 |
1970年 | 619篇 |
1969年 | 690篇 |
1968年 | 791篇 |
1967年 | 717篇 |
1966年 | 701篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
32.
33.
Kristine L S P McVea 《Health psychology》2006,25(5):558-562
OBJECTIVE: This report reviews the evidence that informs the role of health and mental health care providers in addressing youth smoking cessation. DESIGN: Qualitative literature review. RESULTS: Physicians do not consistently screen adolescents for tobacco use and fail to provide recommended cessation advice. Challenges to addressing smoking cessation include the need for procedures to ensure confidentiality and the existence of competing demands to provide other services. Few published studies have specifically addressed the effectiveness of clinical interventions. Interventions that require return visits or follow-up phone contacts are technically difficult to implement in this population. Successful interventions may require resources not available in nonresearch settings. Most studies have used brief clinical intervention as a control condition, making it impossible to evaluate its effectiveness. CONCLUSION: There is little evidence that supports current clinical smoking cessation guidelines for adolescents. More research is needed to develop inexpensive, efficient clinical interventions that can provide youths access to smoking cessation help. Future challenges include reorganizing clinical systems to offer greater counseling by support staff or in electronic formats and to provide effective booster messages and follow-up care in a population that is difficult to track. 相似文献
34.
An electronic apparatus using infrared beams for monitoring the movements of individual bees under dark conditions is described. The searching behavior of workers in an arena was monitored over 2-h periods. Mean ambulatory velocity for one bee over a distance of 100 mm was 45.6±1.51 mm/sec (n=45). Thigmokinesis and temporal activity patterns are illustrated. 相似文献
35.
36.
37.
Carol VanZile-Tamsen Maria Testa Lisa L Harlow Jennifer A Livingston 《Health psychology》2006,25(2):249-254
The current study was designed to gain a better understanding of the nature of the relationship between substance use and sexual risk taking within a community sample of women (N = 1,004). Using confirmatory factor analysis, the authors examined the factor structure of sexual risk behaviors and substance use to determine whether they are best conceptualized as domains underlying a single, higher order, risk-taking propensity. A 2 higher order factor model (sexual risk behavior and substance use) provided the best fit to the data, suggesting that these 2 general risk domains are correlated but independent factors. Sensation seeking had large general direct effects on the 2 risk domains and large indirect effects on the 4 first-order factors and the individual indicators. Negative affect had smaller, yet still significant, effects. Impulsivity and anxiety were unrelated to sexual health risk domains. 相似文献
38.
Susan S Girdler Jane Leserman Robertas Bunevicius Rebecca Klatzkin Cort A Pedersen Kathleen C Light 《Health psychology》2007,26(2):201-213
OBJECTIVE: To examine dysregulation in biological measures associated with histories of abuse in women and whether women with premenstrual dysphoric disorder (PMDD) differ in their dysregulation. DESIGN: Twenty-five women meeting prospective criteria for PMDD and 42 non-PMDD controls underwent structured interview to determine abuse histories and lifetime Axis I diagnoses, excluding those with current Axis I disorders or using medications. MAJOR OUTCOME MEASURES: Plasma cortisol and norepinephrine (NE), heart rate (HR), blood pressure (BP), and vascular resistance index (VRI) were assessed at rest and in response to mental stress. RESULTS: A greater proportion of PMDD women had prior abuse compared with non-PMDD women. Regardless of PMDD status, all abused women had lower plasma NE and higher HRs and tended to have lower plasma cortisol at rest and during stress. Abused women also reported more severe daily emotional and physical symptoms. Greater VRI and BP at rest and during stress were seen only in PMDD women with abuse. CONCLUSION: There is persistent dysregulation in stress-responsive systems in all abused women that cannot be accounted for by current psychiatric illness or medications, and PMDD women may be differentially more vulnerable to the impact of abuse on measures reflecting alpha-adrenergic receptor function. 相似文献
39.
RICHARD L. STREET 《人类交流研究》1984,11(2):139-169
The purpose of this study was to examine speech convergence and speech evaluation in fact-finding interviews conducted in the field. Forty interviewers (ERs), undergraduates enrolled in a class on interviewing processes, conducted 20–30 minute interviews with selected interviewees (EEs), business persons and professionals in fields of interest to the ERs. Speech behaviors examined included response latency, speech rate, and turn duration; these were coded per one minute intervals of each interaction. Time series regression procedures indicated that both ERs and EEs converged speech rate and response latency toward their interlocutors' performances of these behaviors. Although turn duration convergence did not characterize the entire data set, male-male dyads did converge significantly and male (ER)-female (EE) dyads significantly diverged turn duration. Regarding speech evaluation, there was some evidence that greater response latency similarity, greater speech rate and response latency convergence, and faster ER speech and slower EE speech were positively related to the competence and social attractiveness judgments of participants. Limitations and implications are discussed. 相似文献
40.