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   73085篇
  免费   4607篇
  国内免费   277篇
耳鼻咽喉   1150篇
儿科学   2188篇
妇产科学   1360篇
基础医学   7903篇
口腔科学   1508篇
临床医学   7122篇
内科学   15171篇
皮肤病学   1186篇
神经病学   7007篇
特种医学   2579篇
外国民族医学   5篇
外科学   12844篇
综合类   876篇
一般理论   97篇
预防医学   5932篇
眼科学   1526篇
药学   4678篇
中国医学   109篇
肿瘤学   4728篇
  2023年   371篇
  2022年   292篇
  2021年   1722篇
  2020年   987篇
  2019年   1630篇
  2018年   1899篇
  2017年   1379篇
  2016年   1411篇
  2015年   1575篇
  2014年   2409篇
  2013年   3371篇
  2012年   5089篇
  2011年   5283篇
  2010年   2933篇
  2009年   2567篇
  2008年   4660篇
  2007年   4932篇
  2006年   4779篇
  2005年   4762篇
  2004年   4463篇
  2003年   4097篇
  2002年   3796篇
  2001年   575篇
  2000年   487篇
  1999年   604篇
  1998年   656篇
  1997年   556篇
  1996年   480篇
  1995年   524篇
  1994年   502篇
  1993年   424篇
  1992年   377篇
  1991年   383篇
  1990年   308篇
  1989年   292篇
  1988年   284篇
  1987年   264篇
  1986年   272篇
  1985年   366篇
  1984年   430篇
  1983年   360篇
  1982年   514篇
  1981年   485篇
  1980年   452篇
  1979年   205篇
  1978年   272篇
  1977年   255篇
  1976年   200篇
  1975年   219篇
  1973年   183篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
102.
103.
Military personnel may encounter morally injurious events that lead to emotional, social, and spiritual suffering that transcend and/or overlap with mental health diagnoses (e.g., post‐traumatic stress disorder [PTSD]). Advancement of scientific research and potential clinical innovation for moral injury (MI) requires a diversity of measurement approaches. Drawing on results from the bifactor model in Currier et al.'s (2017) psychometric evaluation of the Expressions of Moral Injury Scale‐Military version (EMIS‐M), this study validated a four‐item short form of the instrument with two samples of veterans with a history of war‐zone service. Namely, despite the reduced number of items, the EMIS‐M‐Short Form (SF) yielded favourable internal consistency and comparable levels of convergent validity with theoretically related constructs (e.g., PTSD and struggles with morality and ultimate meaning) as the full‐length version. Notwithstanding the possible utility of distinguishing between self‐ and other‐directed forms of MI, factor analytic results further revealed that the EMIS‐M‐SF was best conceptualized with a unidimensional factorial model that might allow for a general assessment of MI‐related outcomes. Overall, these initial results suggest that the EMIS‐M‐SF may hold promise as a short, reliable, and valid assessment of overall outcomes related to a possible MI.  相似文献   
104.
105.
106.
Dopamine has been implicated in circadian timing underlying the food entrainable oscillator (FEO) circuitry and overexpression of the dopamine D2 receptor (D2R) in the striatum has been reported to reduce motivation to obtain food rewards in operant tasks. In the present study, we explored both of these mechanisms by examining food anticipatory activity (FAA) in dopamine D2 receptor‐overexpressing (D2R‐OE) mice under various durations of food availability. First, we noted that at baseline, there were no differences between D2R‐OE mice and their littermates in activity level, food intake, and body weight or in circadian activity. Under conditions of very restricted food availability (4 or 6 hr), both genotypes displayed FAA. In contrast, under 8‐hr food availability, control mice showed FAA, but D2R‐OE mice did not. Normalization of D2R by administration of doxycycline, a tetracycline analogue, rescued FAA under 8‐hr restricted food. We next tested for circadian regulation of FAA. When given ad libitum access to food, neither D2R‐OE nor controls were active during the daytime. However, after an interval of food restriction, all mice showed elevated locomotor activity at the time of previous food availability in the day, indicating circadian timing of anticipatory activity. In summary, motivation is reduced in D2R‐OE mice but circadian timing behavior is not affected. We conclude that an increase in striatal D2R reduces FAA by modulating motivation and not by acting on a clock mechanism.  相似文献   
107.
Abu Abeid  Adam  Abeid  Subhi Abu  Nizri  Eran  Kuriansky  Joseph  Lahat  Guy  Dayan  Danit 《Obesity surgery》2022,32(5):1617-1623
Obesity Surgery - Laparoscopic sleeve gastrectomy (SG) is a common and effective bariatric surgery, with low postoperative complication rates. It is important to define modifiable risk factors for...  相似文献   
108.
109.
110.
Osteogenesis imperfecta (OI) is a collagen-related bone disorder characterized by fragile osteopenic bone and muscle weakness. We have previously shown that the soluble activin receptor type IIB decoy (sActRIIB) molecule increases muscle mass and improves bone strength in the mild to moderate G610C mouse model of OI. The sActRIIB molecule binds multiple transforming growth factor-β (TGF-β) ligands, including myostatin and activin A. Here, we investigate the musculoskeletal effects of inhibiting activin A alone, myostatin alone, or both myostatin and activin A in wild-type (Wt) and heterozygous G610C (+/G610C) mice using specific monoclonal antibodies. Male and female Wt and +/G610C mice were treated twice weekly with intraperitoneal injections of monoclonal control antibody (Ctrl-Ab, Regn1945), anti-activin A antibody (ActA-Ab, Regn2476), anti-myostatin antibody (Mstn-Ab, Regn647), or both ActA-Ab and Mstn-Ab (Combo, Regn2476, and Regn647) from 5 to 16 weeks of age. Prior to euthanasia, whole body composition, metabolism and muscle force generation assessments were performed. Post euthanasia, hindlimb muscles were evaluated for mass, and femurs were evaluated for changes in microarchitecture and biomechanical strength using micro–computed tomography (μCT) and three-point bend analyses. ActA-Ab treatment minimally impacted the +/G610C musculoskeleton, and was detrimental to bone strength in male +/G610C mice. Mstn-Ab treatment, as previously reported, resulted in substantial increases in hindlimb muscle weights and overall body weights in Wt and male +/G610C mice, but had minimal skeletal impact in +/G610C mice. Conversely, the Combo treatment outperformed ActA-Ab alone or Mstn-Ab alone, consistently increasing hindlimb muscle and body weights regardless of sex or genotype and improving bone microarchitecture and strength in both male and female +/G610C and Wt mice. Combinatorial inhibition of activin A and myostatin more potently increased muscle mass and bone microarchitecture and strength than either antibody alone, recapturing most of the observed benefits of sActRIIB treatment in +/G610C mice. © 2022 American Society for Bone and Mineral Research (ASBMR).  相似文献   
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