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   7339篇
  免费   610篇
  国内免费   63篇
耳鼻咽喉   68篇
儿科学   326篇
妇产科学   188篇
基础医学   926篇
口腔科学   134篇
临床医学   692篇
内科学   1750篇
皮肤病学   60篇
神经病学   902篇
特种医学   235篇
外科学   791篇
综合类   141篇
一般理论   2篇
预防医学   844篇
眼科学   126篇
药学   300篇
中国医学   1篇
肿瘤学   526篇
  2021年   70篇
  2019年   60篇
  2018年   96篇
  2017年   78篇
  2016年   68篇
  2015年   93篇
  2014年   146篇
  2013年   209篇
  2012年   297篇
  2011年   285篇
  2010年   188篇
  2009年   188篇
  2008年   309篇
  2007年   331篇
  2006年   294篇
  2005年   288篇
  2004年   265篇
  2003年   324篇
  2002年   276篇
  2001年   263篇
  2000年   271篇
  1999年   239篇
  1998年   88篇
  1997年   91篇
  1996年   80篇
  1995年   74篇
  1994年   65篇
  1993年   75篇
  1992年   219篇
  1991年   218篇
  1990年   202篇
  1989年   167篇
  1988年   162篇
  1987年   166篇
  1986年   132篇
  1985年   160篇
  1984年   110篇
  1983年   82篇
  1982年   69篇
  1981年   68篇
  1979年   119篇
  1978年   90篇
  1977年   56篇
  1976年   63篇
  1975年   61篇
  1974年   72篇
  1973年   59篇
  1972年   71篇
  1970年   48篇
  1966年   52篇
排序方式: 共有8012条查询结果,搜索用时 0 毫秒
81.
Serial dexamethasone suppression tests (DST), obtained during a course of electroconvulsive therapy in 43 severely depressed patients, did not exhibit relationships between the initial DST, final DST, or the change in DST with clinical outcome measures at the time of discharge. In 37 patients reviewed six months after discharge, no relationship with the continuation of improvement, rehospitalization, or suicide was found. We are unable to confirm a clinical application for the DST in the management of patients during a course of convulsive therapy.  相似文献   
82.
A popular rule of thumb has often prevailed in treating oral cancer: Try one modality first; if it fails, try the other--the chance for cure will still be good. To study this dogma, a group of 160 consecutive patients with oral cavity squamous carcinoma were reviewed. A hypothesis was formed: secondary treatment for recurrent cancer, whether surgery after radiation failure or vice versa, would salvage essentially as many patients as primary treatment, say within 15%. Results show a large difference in success rates between first and second treatments when all stages are considered together, a difference well over 15 percentage points. Regarding each stage separately, the largest difference occurs in stage II (28 percentage points); other stages exceed 15 point differences. No significant differences in successful salvage occur between "home" failures and "elsewhere" failures. Local recurrence was a major cause of failure in both groups (55%). We conclude that recurrence of oral squamous cancer after first treatment markedly reduces patients' chance for cure.  相似文献   
83.
Lupus vulgaris responding to double antituberculous therapy   总被引:1,自引:0,他引:1  
A patient with a 3 by 4 cm ulcerated lesion on the nose and upper lip in whom previous antibiotics and antifungal treatments for a "mixed infection" were of no avail is presented. Her history revealed that she has had pulmonary and pharyngeal tuberculosis and subsequently scrofuloderma of cervical lymph nodes. She eventually responded well to isoniazid, rifampin, and pyridoxine therapy.  相似文献   
84.
Prevention Science - There is evidence that universal school-based mindfulness training (SBMT) can have positive effects for young people. However, it is unknown who benefits most from such...  相似文献   
85.
BackgroundEntrustable Professional Activities (EPAs) contain narrative ‘entrustment roadmaps’ designed to describe specific behaviors associated with different entrustment levels. However, these roadmaps were created using expert committee consensus, with little data available for guidance. Analysis of actual EPA assessment narrative comments using natural language processing may enhance our understanding of resident entrustment in actual practice.MethodsAll text comments associated with EPA microassessments at a single institution were combined. EPA—entrustment level pairs (e.g. Gallbladder Disease—Level 1) were identified as documents. Latent Dirichlet Allocation (LDA), a common machine learning algorithm, was used to identify latent topics in the documents associated with a single EPA. These topics were then reviewed for interpretability by human raters.ResultsOver 18 months, 1015 faculty EPA microassessments were collected from 64 faculty for 80 residents. LDA analysis identified topics that mapped 1:1 to EPA entrustment levels (Gammas >0.99). These LDA topics appeared to trend coherently with entrustment levels (words demonstrating high entrustment were consistently found in high entrustment topics, word demonstrating low entrustment were found in low entrustment topics).ConclusionsLDA is capable of identifying topics relevant to progressive surgical entrustment and autonomy in EPA comments. These topics provide insight into key behaviors that drive different level of resident autonomy and may allow for data-driven revision of EPA entrustment maps.  相似文献   
86.
87.
Greenberg DS 《Lancet》1990,336(8730):1568-1569
  相似文献   
88.
89.
Summary We measured plasma levels of pyridoxal-5-phosphate (PLP), a cofactor form of vitamin B6 and apparent natural substrate for alkaline phosphatase (ALP), in carriers and in non-carriers of the severe perinatal and infantile forms of hypophosphatasia, both before and after an oral load of pyridoxine (i.e. 1/3 mg/kg body weight). The assignment of carrier status was determined by serum ALP activity, level of serum inorganic phosphate, and if necessary urinary phosphoethanolamine excretion. Plasma PLP levels were significantly increased in the carriers both before and especially after B6 loading.  相似文献   
90.
NCVHS has made recommendations to the DHHS to standardize 42 core health data elements, a number of which relate to medical conditions and services. The committee has asked the DHHS Data Council to actively promote, both within the department and externally, standardization of data elements and definitions where substantial consensus already exists. For those elements that have been recognized as significant core data elements, but for which there is not consensus on approach or definition, the NCVHS is recommending that the Data Council support the formation of a public-private working group to conduct further study and evaluation. This group, or a separate group, could also be the focus for evaluating additions to the list of core data elements and for setting up methods for testing and promulgating the final products. The coming 12-18 months will be exceedingly important for health data standardization efforts in the US as the DHHS responds to both the NCVHS recommendations and the legislation recently enacted by Congress.  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