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   2361415篇
  免费   189594篇
  国内免费   7344篇
耳鼻咽喉   30495篇
儿科学   76950篇
妇产科学   65263篇
基础医学   337655篇
口腔科学   65582篇
临床医学   219353篇
内科学   470707篇
皮肤病学   53996篇
神经病学   193612篇
特种医学   92296篇
外国民族医学   579篇
外科学   352079篇
综合类   53240篇
现状与发展   5篇
一般理论   968篇
预防医学   195503篇
眼科学   52238篇
药学   169715篇
  8篇
中国医学   3921篇
肿瘤学   124188篇
  2018年   24508篇
  2016年   22079篇
  2015年   24894篇
  2014年   34778篇
  2013年   52820篇
  2012年   67601篇
  2011年   72529篇
  2010年   43813篇
  2009年   42418篇
  2008年   68258篇
  2007年   72896篇
  2006年   73430篇
  2005年   71520篇
  2004年   68508篇
  2003年   66149篇
  2002年   63563篇
  2001年   107046篇
  2000年   109709篇
  1999年   92362篇
  1998年   27611篇
  1997年   24866篇
  1996年   25831篇
  1995年   25413篇
  1994年   23625篇
  1993年   22211篇
  1992年   75735篇
  1991年   74093篇
  1990年   71687篇
  1989年   68732篇
  1988年   63772篇
  1987年   62684篇
  1986年   59307篇
  1985年   56990篇
  1984年   43394篇
  1983年   37296篇
  1982年   22964篇
  1981年   20785篇
  1980年   19572篇
  1979年   40394篇
  1978年   29522篇
  1977年   24893篇
  1976年   22914篇
  1975年   24353篇
  1974年   29151篇
  1973年   28290篇
  1972年   26352篇
  1971年   24481篇
  1970年   22755篇
  1969年   21425篇
  1968年   20050篇
排序方式: 共有10000条查询结果,搜索用时 328 毫秒
91.
92.
As millions of people turn to social media for health information, better understanding the factors that guide health-related judgments and perceptions in this context is imperative. We report on two Web experiments (n > 400 total) examining the power of society’s widespread weight bias and related stereotypes to influence nutrition judgments in social media spaces. In Experiment 1, meals were judged as lower in nutritional quality when the person who recommended them (the source) was depicted as obese rather than of normal weight, an effect mediated by stereotypic beliefs about the source as a generally unhealthy person. Experiment 2 replicated this effect, which—notably—remained significant when controlling for objective nutritional information (calories and fat content). Results highlight spillover effects of weight bias that extend beyond person perception to color impressions of objects (here, food) that are associated with stigmatized attributes. Implications for everyday nutrition judgments and public health are considered.  相似文献   
93.
94.
95.
96.
97.
Preimplantation genetic diagnosis (PGD) was originally developed to diagnose embryo-related genetic abnormalities for couples who present a high risk of a specific inherited disorder. Because this technology involves embryo selection, the medical, bioethical, and legal implications of the technique have been debated, particularly when it is used to select features that are not related to serious diseases. Although several initiatives have attempted to achieve regulatory harmonization, the diversity of healthcare services available and the presence of cultural differences have hampered attempts to achieve this goal. Thus, in different countries, the provision of PGD and regulatory frameworks reflect the perceptions of scientific groups, legislators, and society regarding this technology. In Brazil, several texts have been analyzed by the National Congress to regulate the use of assisted reproduction technologies. Legislative debates, however, are not conclusive, and limited information has been published on how PGD is specifically regulated. The country requires the development of new regulatory standards to ensure adequate access to this technology and to guarantee its safe practice. This study examined official documents published on PGD regulation in Brazil and demonstrated how little direct oversight of PGD currently exists. It provides relevant information to encourage reflection on a particular regulation model in a Brazilian context, and should serve as part of the basis to enable further reform of the clinical practice of PGD in the country.  相似文献   
98.
99.
100.
A 48-year-old smoker with a history of hyperthyroidism treated 10 years prior to presentation with radioactive iodine ablation of the thyroid gland presented to his ophthalmologist with a 2-week history of transient loss of vision in the right eye occurring for 1 to 2 hours each morning. He denied ocular pain, diplopia or change in the prominence of one or both eyes. Examination revealed 2 mm of relative proptosis on the right, bilateral temporal flare and lower lid retraction. There was minimal upper lid retraction and no evidence of lid lag. Ocular motility was full. Dilated fundoscopic examination revealed bilateral optic nerve edema, right more than left. CT of the orbit demonstrated enlargement of the extraocular muscles bilaterally with marked enlargement of the right medial rectus and left inferior rectus muscles resulting in crowding at the orbital apex bilaterally. Laboratory testing revealed the patient to be hyperthyroid. The patient was treated with high dose oral steroids followed by orbital radiation. Hyperthyroidism was managed by the patient’s primary care physician. Visual symptoms rapidly improved with oral steroids and orbital radiation. Optic nerve edema completely resolved. Repeat CT imaging demonstrated a reduction in the enlargement of the extraocular muscles with relief of bilateral optic nerve compression.  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