首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1599404篇
  免费   133613篇
  国内免费   2587篇
耳鼻咽喉   21652篇
儿科学   52941篇
妇产科学   46240篇
基础医学   227814篇
口腔科学   47207篇
临床医学   140843篇
内科学   314631篇
皮肤病学   34107篇
神经病学   130098篇
特种医学   64748篇
外国民族医学   474篇
外科学   243861篇
综合类   39706篇
现状与发展   3篇
一般理论   544篇
预防医学   122771篇
眼科学   36457篇
药学   121277篇
  2篇
中国医学   2975篇
肿瘤学   87253篇
  2018年   14791篇
  2016年   12914篇
  2015年   15044篇
  2014年   20664篇
  2013年   31375篇
  2012年   42594篇
  2011年   44806篇
  2010年   26370篇
  2009年   25336篇
  2008年   43036篇
  2007年   45275篇
  2006年   46091篇
  2005年   44700篇
  2004年   44119篇
  2003年   42201篇
  2002年   41310篇
  2001年   75693篇
  2000年   78338篇
  1999年   66399篇
  1998年   17741篇
  1997年   16340篇
  1996年   16316篇
  1995年   16024篇
  1994年   15075篇
  1993年   14219篇
  1992年   55445篇
  1991年   53780篇
  1990年   52566篇
  1989年   50839篇
  1988年   47231篇
  1987年   46564篇
  1986年   44286篇
  1985年   42847篇
  1984年   32036篇
  1983年   27571篇
  1982年   16147篇
  1981年   14439篇
  1980年   13565篇
  1979年   30464篇
  1978年   21068篇
  1977年   17767篇
  1976年   16697篇
  1975年   17577篇
  1974年   21492篇
  1973年   20675篇
  1972年   18856篇
  1971年   17771篇
  1970年   16290篇
  1969年   15268篇
  1968年   13955篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
241.
Objective: A multidisciplinary vocational rehabilitation programme, the Vocational Enablement Protocol (VEP) was developed to address the specific needs of employees with hearing difficulties. In the current study we evaluated the process of implementing the VEP in audiologic care among employees with hearing impairment. Design: In conjunction with a randomized controlled trial, we collected and analysed data on seven process parameters: recruitment, reach, fidelity, dose delivered, dose received and implemented, satisfaction, and perceived benefit. Study sample: Sixty-six employees with hearing impairment participated in the VEP. The multidisciplinary team providing the VEP comprised six professionals. Results: The professionals performed the VEP according to the protocol. Of the recommendations delivered by the professionals, 31% were perceived as implemented by the employees. Compliance rate was highest for hearing-aid uptake (51%). Both employees and professionals were highly satisfied with the VEP. Participants rated good perceived benefit from it. Conclusions: Our results indicate that the VEP could be a useful treatment for employees with hearing difficulties from a process evaluation perspective. Implementation research in the audiological setting should be encouraged in order to further provide insight into parameters facilitating or hindering successful implementation of an intervention and to improve its quality and efficacy.  相似文献   
242.
243.
244.
Formaldehyde is the most commonly used fixative chemical for the preservation of human cadavers used for educational purposes in the United States. Formaldehyde is also a known carcinogenic agent whose exposure level is regulated by guidelines of the Occupational Safety and Health Administration. Various methods for formaldehyde neutralization exist, yet many donations programs do not take any steps to neutralize the formaldehyde in embalmed donor bodies. The effectiveness of monoethanolamine (MEA) in neutralizing formaldehyde is well documented when used as a final injection during embalming. The purpose of this study is to report the effectiveness of several post‐embalming techniques of formaldehyde neutralization. Twenty‐four donor bodies were assigned to four experimental groups of six. For the three experimental groups, the techniques tested involve delivery of a 20:1 dilution of deionized water:MEA via recannulization and gravity flow infusion, compartment injection, and alternate wetting solution containing four percent MEA. Our results indicated that spray bottle delivery was not effective in neutralization of formaldehyde compared to the control group, but that formaldehyde levels decreased when recannulization or compartment injection were used. The most effective method of formaldehyde neutralization was compartment injection of MEA solution (P < 0.01). The results of this study indicate that, in situations where MEA is not used as a final infusion during embalming, compartment injection of MEA solution is an effective method of formaldehyde neutralization. Clin. Anat. 28:449–454, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
245.
β-defensin peptides are a large family of antimicrobial peptides. Although they kill microbes in vitro and interact with immune cells, the precise role of these genes in vivo remains uncertain. Despite their inducible presence at mucosal surfaces, their main site of expression is the epididymis. Recent evidence suggests that a major function of these peptides is in sperm maturation. In addition to previous work suggesting this, work at the MRC Human Genetics Unit, Edinburgh, has shown that homozygous deletion of a cluster of nine β-defensin genes in the mouse results in profound male sterility. The spermatozoa derived from the mutants had reduced motility and increased fragility. Epididymal spermatozoa isolated from the cauda region of the homozygous mutants demonstrated precocious capacitation and increased spontaneous acrosome reactions compared with those from wild-types. Despite this, these mutant spermatozoa had reduced ability to bind to the zona pellucida of oocytes. Ultrastructural examination revealed a disintegration of the microtubule structure of mutant-derived spermatozoa isolated from the epididymal cauda region, but not from the caput. Consistent with premature acrosome reaction and hyperactivation, spermatozoa from mutant animals had significantly increased intracellular calcium content. This work demonstrates that in vivo β-defensins are essential for successful sperm maturation, and that their disruption alters intracellular calcium levels, which most likely leads to premature activation and spontaneous acrosome reactions that result in hyperactivation and loss of microtubule structure of the axoneme. Determining which of the nine genes are responsible for the phenotype and the relevance to human sperm function is important for future work on male infertility.  相似文献   
246.
247.
248.
Parhiala  P.  Ranta  K.  Gergov  V.  Kontunen  J.  Law  R.  La Greca  A. M.  Torppa  M.  Marttunen  M. 《School mental health》2020,12(2):265-283

In order to offer early and accessible treatment for adolescents with depression, brief and effective treatments in adolescents’ everyday surroundings are needed. This randomized controlled trial studied the preliminary effectiveness, feasibility, and acceptability of interpersonal counseling (IPC) and brief psychosocial support (BPS) in school health and welfare services. The study was conducted in the 28 lower secondary schools of a large city in Southern Finland, randomized to provide either IPC or BPS. Help-seeking 12–16-year-old adolescents with mild-to-moderate depression, with and without comorbid anxiety, were included in the study. Fifty-five adolescents received either 6 weekly sessions of IPC or BPS and two follow-up sessions. Outcome measures included self- and clinician-rated measures of depression, global functioning, and psychological distress/well-being. To assess feasibility and acceptability of the treatments, adolescents’ and counselors’ treatment compliance and satisfaction with treatment were assessed. Both treatments were effective in reducing depressive disorders and improving adolescents’ overall functioning and well-being. At post-treatment, in both groups, over 50% of adolescents achieved recovery based on self-report and over 70% based on observer report. Effect sizes for change were medium or large in both groups at post-treatment and increased at 6-month follow-up. A trend indicating greater baseline symptom severity among adolescents treated in the IPC-providing schools was observed. Adolescents and counselors in both groups were satisfied with the treatment, and 89% of the adolescents completed the treatments and follow-ups. This trial suggests that both IPC and BPS are feasible, acceptable, and effective treatments for mild-to-moderate depression in the school setting. In addition, IPC seems effective even if comorbid anxiety exists. Our study shows that brief, structured interventions, such as IPC and BPS, are beneficial in treating mild-to-moderate depression in school settings and can be administered by professionals working at school.

Trial registrationhttp://www.clinicaltrials.gov. Unique identifier: NCT03001245.

  相似文献   
249.
250.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号