全文获取类型
收费全文 | 5442篇 |
免费 | 672篇 |
国内免费 | 244篇 |
专业分类
电工技术 | 50篇 |
技术理论 | 2篇 |
综合类 | 238篇 |
化学工业 | 1457篇 |
金属工艺 | 126篇 |
机械仪表 | 166篇 |
建筑科学 | 216篇 |
矿业工程 | 41篇 |
能源动力 | 13篇 |
轻工业 | 235篇 |
水利工程 | 44篇 |
石油天然气 | 50篇 |
武器工业 | 74篇 |
无线电 | 809篇 |
一般工业技术 | 1085篇 |
冶金工业 | 1295篇 |
原子能技术 | 168篇 |
自动化技术 | 289篇 |
出版年
2024年 | 28篇 |
2023年 | 242篇 |
2022年 | 532篇 |
2021年 | 629篇 |
2020年 | 310篇 |
2019年 | 278篇 |
2018年 | 212篇 |
2017年 | 224篇 |
2016年 | 201篇 |
2015年 | 207篇 |
2014年 | 241篇 |
2013年 | 212篇 |
2012年 | 189篇 |
2011年 | 287篇 |
2010年 | 259篇 |
2009年 | 237篇 |
2008年 | 208篇 |
2007年 | 225篇 |
2006年 | 234篇 |
2005年 | 264篇 |
2004年 | 202篇 |
2003年 | 168篇 |
2002年 | 138篇 |
2001年 | 107篇 |
2000年 | 62篇 |
1999年 | 48篇 |
1998年 | 37篇 |
1997年 | 39篇 |
1996年 | 25篇 |
1995年 | 26篇 |
1994年 | 24篇 |
1993年 | 36篇 |
1992年 | 26篇 |
1991年 | 10篇 |
1990年 | 19篇 |
1989年 | 27篇 |
1988年 | 21篇 |
1987年 | 10篇 |
1986年 | 13篇 |
1984年 | 10篇 |
1979年 | 5篇 |
1974年 | 3篇 |
1966年 | 7篇 |
1965年 | 6篇 |
1964年 | 14篇 |
1963年 | 3篇 |
1961年 | 3篇 |
1960年 | 3篇 |
1959年 | 4篇 |
1955年 | 6篇 |
排序方式: 共有6358条查询结果,搜索用时 0 毫秒
41.
Examined V. Axlines's book, Play Therapy (1947) which includes 8 basic principles on non-directive play therapy. Student responses to learning these principles in play therapy classes were also examined. Each student was assigned a play therapy client and was observed and assisted directly by the instructor, a licensed clinical psychologist. Clients were mildly trouble children (aged 5–10 yrs) and were selected from a referral base by the instructor as appropriate for the course. As the semester progressed and students gained direct experience, weekly small (3–4 student) group discussions were held to explore in-depth understanding of play therapy principles and how these principles are put into practice. It is concluded that Axline's book remains a classic text and a foremost resource in the field. Coupling it with experiential learning is an invaluable basis for teaching play therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
42.
43.
HSV-tk基因/GCV系统治疗肿瘤的旁观者效应与缝隙连接关系的研究 总被引:1,自引:0,他引:1
目的 探讨单纯疱疹病毒胸苷激酶(HSV-tk)基因/丙氧鸟苷(GCV)系统杀伤肿瘤细胞时旁观者效应与细胞间缝隙连接的关系。方法 用PA317细胞包装STK质粒(逆转录病毒载体介导的HSV-tk基因),形成假逆转录病毒颗粒,转染有缝隙连接的大鼠胶质瘤细胞C6和无缝隙连接的入宫颈癌细胞 Hela,制成 C6 tk+和 Helatk+细胞,将不同比例的C6和 C6 tk+、Hela和 Hela tk+细胞混合,每种比例8孔,培养 24h后 4孔加入含0.5μg/mlGCV的培养基,4孔作对照,6d后用MTT法测量细胞存活率。在两个培养皿中放入周围粘有33mm高滤纸的载玻片,分别接种 C6、C6 tk+细胞。细胞 80%汇合后将载玻片互换,并加入含0.5μg/ml GCV的培养基,6d后观察细胞形态。结果C6细胞组存在旁观者效应,Heal细胞组不存在旁观者效应。培养皿中tk+细胞大部分被杀死,tk-细胞无变化。结论HSV-tk基因/GCV系统杀伤肿瘤细胞时旁观者效应与细胞间缝隙连接有关。 相似文献
44.
V. V. Korchevskii 《Measurement Techniques》2006,49(5):517-523
The particular features of the measurement of the continuous acoustic emission when metals are stretched are considered. It
is shown that the measured physical quantity should be the intensity of the acoustic radiation. Sources of systematic error
are indicated, namely, the rigidity of the testing machine, the rate of displacement of the mobile crossarm, and the dimensions
and shape of the samples.
__________
Translated from Izmeritel’naya Tekhnika, No. 5, pp. 64–68, May, 2006. 相似文献
45.
通过对同一空调风系统的不同区域采用末端变流量、电辅热微调等多种控制方法使小面积有精密空调要求的房间达到恒温恒湿目的。 相似文献
46.
Hicks Thomas V.; Leitenberg Harold; Barlow David H.; Gorman Jack M.; Shear M. Katherine; Woods Scott W. 《Canadian Metallurgical Quarterly》2005,73(3):506
The authors explored the prognostic value of 3 different types of catastrophic cognitions in the treatment of panic disorder with and without mild-to-moderate agoraphobia using a sample of 143 participants who received either cognitive-behavioral therapy (CBT) or imipramine in a randomized controlled trial. Stronger fears of social catastrophes both prior to and following treatment with CBT or imipramine were associated with a poorer outcome. In contrast, cognitions involving physical or mental catastrophes were unrelated to outcome, regardless of whether these thoughts were measured prior to or following treatment. These findings are consistent with the notion that although the intensity of physical catastrophe cognitions may best discriminate between panic disorder and other anxiety disorders, it is the intensity of social catastrophe cognitions that is most closely tied to success in treating this disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
47.
The relationship between treatment outcome and the extent to which participants completed homework assignments was evaluated among 60 cocaine-dependent individuals assigned to cognitive-behavioral therapy (CBT). Homework was assigned in 72% of all sessions and initiated by participants in 48% of the sessions in which it was assigned. Completion of homework was unrelated to participants' baseline characteristics and several indicators of treatment compliance. Participants who completed more homework assignments demonstrated significantly greater increases in the quantity and quality of their coping skills and used significantly less cocaine during treatment and through a 1-year follow-up. These data suggest that the extent to which participants are willing to complete extrasession assignments may be an important mediator of response to CBT. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
Atkins David C.; Yi Jean; Baucom Donald H.; Christensen Andrew 《Canadian Metallurgical Quarterly》2005,19(3):470
The revelation of an affair is often an emotionally explosive event for a couple, yet little is known about specific individual and relationship factors that accompany infidelity. The present study examined the qualities of individuals and couples that differentiate couples with (n = 19) and without (n = 115) infidelity using couples from a randomized clinical trial of marital therapy. Findings indicated that couples with infidelity showed greater marital instability, dishonesty, arguments about trust, narcissism, and time spent apart. Gender also proved to be a significant moderator of several effects. Men who had participated in affairs showed increased substance use, were older, and were more sexually dissatisfied. Results offer initial clues to concomitants of affairs for couple therapists. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
49.
Weaver Kathryn E.; Llabre María M.; Durán Ron E.; Antoni Michael H.; Ironson Gail; Penedo Frank J.; Schneiderman Neil 《Canadian Metallurgical Quarterly》2005,24(4):385
The authors tested a structural model that incorporated age, time since diagnosis, social support, coping, and negative mood as predictors of medication adherence and HIV viral load on 188 men and 134 women on highly active antiretroviral therapy (HAART). The authors used psychosocial latent factors formed from baseline measures to predict latent factors of adherence, as assessed by electronic monitoring and self-report, and viral load defined by indicators assessed over a 15-month period. Results from the model indicate that greater negative mood and lower social support are related to greater use of avoidance-oriented coping strategies. Use of these coping strategies by patients on HAART is related to poorer medication adherence and, subsequently, higher viral load. This model advances researchers' understanding of the contribution of psychosocial variables in predicting treatment adherence and disease progression in HIV-positive men and women. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
50.
Globalization is upon us, resulting in almost daily exposure to and interaction with highly diverse populations. To practice ethical play therapy, play therapists must become culturally competent. Play therapists are called on both to address cultural issues in therapy and to facilitate children's pride in, and preservation of, their culture. Despite this, the existing literature on cultural competence in psychotherapy has rarely been applied to play therapy practice. The author's goal is to do just that so as to provide play therapists with a model relevant to their work. Play therapists must first fully understand the concept of culture and its potential impact on their own lives, the lives of their clients, and the play therapy process. Second, play therapists need to develop adequate levels of culturally related awareness, skills, and knowledge. Last, they can ensure the work they do is more culturally sensitive and competent by following basic guidelines. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献