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   20514篇
  免费   1403篇
  国内免费   72篇
耳鼻咽喉   347篇
儿科学   613篇
妇产科学   356篇
基础医学   2453篇
口腔科学   258篇
临床医学   2031篇
内科学   4497篇
皮肤病学   482篇
神经病学   2012篇
特种医学   723篇
外科学   2948篇
综合类   243篇
现状与发展   1篇
一般理论   18篇
预防医学   1854篇
眼科学   557篇
药学   1289篇
中国医学   23篇
肿瘤学   1284篇
  2023年   109篇
  2022年   208篇
  2021年   457篇
  2020年   288篇
  2019年   426篇
  2018年   539篇
  2017年   367篇
  2016年   434篇
  2015年   471篇
  2014年   690篇
  2013年   984篇
  2012年   1401篇
  2011年   1491篇
  2010年   798篇
  2009年   769篇
  2008年   1247篇
  2007年   1358篇
  2006年   1329篇
  2005年   1290篇
  2004年   1300篇
  2003年   1124篇
  2002年   1009篇
  2001年   233篇
  2000年   184篇
  1999年   230篇
  1998年   256篇
  1997年   177篇
  1996年   159篇
  1995年   169篇
  1994年   142篇
  1993年   120篇
  1992年   137篇
  1991年   112篇
  1990年   89篇
  1989年   107篇
  1988年   103篇
  1987年   98篇
  1986年   114篇
  1985年   95篇
  1984年   111篇
  1983年   86篇
  1982年   99篇
  1981年   120篇
  1980年   95篇
  1979年   86篇
  1978年   78篇
  1977年   82篇
  1976年   50篇
  1975年   53篇
  1974年   50篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
13.
14.
Factors affecting survival in maxillary sinus cancer.   总被引:4,自引:0,他引:4  
PURPOSE: The study goal was to determine survival parameters and clinical factors influencing survival for maxillary sinus malignancies. METHODS: Cases of maxillary sinus malignancy for the time period 1988 to 1998 were extracted from the Surveillance, Epidemiology and End Results database. Cases with distant metastatic disease at presentation were excluded. Clinical information, including tumor histology, grade and stage, and extent of surgery and radiation therapy, were determined. Kaplan-Meier survival and Cox proportional hazards analyses were conducted to determine the influence of these factors on overall survival. RESULTS: The study sample was composed of 650 patients with maxillary sinus cancer (mean age, 64 years; male-to-female ratio, 3:2). The most common histology was squamous cell carcinoma (61.7%), followed by adenoid cystic carcinoma (9.8%). The overall mean (median) survival was 52 months (25 months), and 77.5% and 7.4% of patients presented with advanced (T3/T4) disease or cervical metastasis, respectively. Radiation therapy was administered in 441 patients (67.9%) and significantly improved survival mainly for those with T4 lesions. On multivariate analysis, increasing age, T stage, N stage, and tumor grade independently predicted poorer survival, whereas gender did not. Adenoid cystic carcinoma exhibited a significantly improved overall survival (P <.001). CONCLUSIONS: Survival for patients with maxillary sinus cancer is determined not only by TNM staging but also by tumor histology and grade. TNM staging effectively stratifies patients according to survival. Radiation therapy significantly improves survival for those with T4 lesions.  相似文献   
15.
Current treatment of acute stroke remains unsatisfactory. This review presents experimental and clinical data which suggest that mild induced hypothermia could be a potent and practicable neuroprotective treatment of acute ischaemic stroke and intracerebral haemorrhage. Hypothermia, if proven to be safe, effective and widely practicable in patients with acute stroke, could have an enormous positive impact on reducing the burden of stroke worldwide. Critical issues that will need to be considered in a well designed randomised controlled trial of induced hypothermia in acute stroke patients are discussed.  相似文献   
16.
17.
Optic nerve sheath meningiomas are by far the most common tumors of the optic nerve sheath. The diagnosis can be suspected in most cases from clinical findings and supported by the results of neuroimaging, obviating tissue biopsy in the majority of cases. Observation may be appropriate in patients with mild or no visual deficit or in whom visual loss is not progressing, whereas stereotactic fractionated radiation therapy has been demonstrated to improve or stabilize vision in progressive or advanced cases. Attempts at surgical excision, and even biopsy, of optic nerve sheath meningiomas are associated with a high risk of blindness and should be reserved for the rare case of an anteriorly located, primarily exophytic tumor with focal involvement of the dural sheath.  相似文献   
18.
We performed a literature search for all clinical studies reporting outcomes in patients with the acquired immunodeficiency syndrome (AIDS) receiving granulocyte-macrophage colony-stimulating factor (GM-CSF) for any indication. Safety outcomes included human immunodeficiency virus replication, immune status, and frequency of opportunistic infections and neoplasms. Data were synthesized qualitatively. We identified 22 studies (274 patients): 12 addressed AIDS neutropenia, 8 AIDS cancer therapy, and 2 opportunistic infections. Viral burden was assessed by serum p24Ag in 15 studies. Nine reported no change in levels, three net decreases, and three net increases. All studies showing net increases involved patients receiving GM-CSF without a concurrent antiretroviral. The CD4 counts were unchanged in 5 studies, increased in 3, and not reported in 14. The incidence of neoplasms or new opportunistic infections was low. The literature suggests no increased risk of viral replication or clinical deterioration in patients with AIDS who take GM-CSF concurrently with zidovudine.  相似文献   
19.
20.
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