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   7389篇
  免费   682篇
  国内免费   91篇
耳鼻咽喉   66篇
儿科学   151篇
妇产科学   277篇
基础医学   958篇
口腔科学   146篇
临床医学   763篇
内科学   1389篇
皮肤病学   163篇
神经病学   610篇
特种医学   385篇
外科学   1030篇
综合类   194篇
一般理论   1篇
预防医学   455篇
眼科学   235篇
药学   501篇
中国医学   29篇
肿瘤学   809篇
  2023年   49篇
  2022年   77篇
  2021年   212篇
  2020年   169篇
  2019年   239篇
  2018年   255篇
  2017年   169篇
  2016年   201篇
  2015年   257篇
  2014年   308篇
  2013年   448篇
  2012年   518篇
  2011年   507篇
  2010年   324篇
  2009年   275篇
  2008年   398篇
  2007年   389篇
  2006年   360篇
  2005年   373篇
  2004年   332篇
  2003年   267篇
  2002年   262篇
  2001年   215篇
  2000年   185篇
  1999年   196篇
  1998年   71篇
  1997年   54篇
  1996年   49篇
  1995年   46篇
  1994年   29篇
  1993年   32篇
  1992年   103篇
  1991年   93篇
  1990年   73篇
  1989年   74篇
  1988年   69篇
  1987年   64篇
  1986年   57篇
  1985年   58篇
  1984年   56篇
  1983年   25篇
  1982年   23篇
  1981年   19篇
  1980年   14篇
  1979年   21篇
  1978年   18篇
  1977年   15篇
  1975年   13篇
  1974年   15篇
  1969年   11篇
排序方式: 共有8162条查询结果,搜索用时 15 毫秒
1.
Thirty-nine primary surgical cases for correction of congenital aural atresia were reviewed for complications and long-term hearing results. Hearing averages of 25 dB for mild atresia, 40 dB for moderate atresia, and 46 dB for severe atresia were obtained. Serviceable hearing was achieved in 64% of the cases. The two most frequent complications were stenosis and recurrent infections of the cavity and canal skin, with an incidence of 33% and 31%, respectively. Use of split-thickness instead of full-thickness skin graft was associated with fewer complications. The goal of this review is also to share the experience of the senior author in the management of this complex problem.  相似文献   
2.
3.
Radionuclide brain scintigraphy and computed tomography (CT) demonstrated cerebral lesions in two patients with acquired immunodeficiency disease syndrome (AIDS) complicated by opportunistic infection of the brain. In the detection of these cerebral lesions, [99mTc]DTPA radionuclide scintigraphy was as reliable as CT. Since malignant lymphoma involving the brain has been seen with increasing frequency in patients with AIDS, the positive brain scan alone is nonspecific and should be correlated appropriately with the clinical setting.  相似文献   
4.
5.
6.
7.
Monoamine oxidase (MAO) A and B play an important role in regulating levels of biogenic amines. MAO A and B cDNAs have been cloned and the deduced amino acids share 73% sequence identity. The genes for MAOA and B are comprised of 15 exons interspersed by 14 introns, span at least 60 kb and exhibit identical exon-intron organization. These findings suggest that the MAOA and MAOB genes are derived from the duplication of a common ancestral gene. The core promoter region of MAOA is comprised of two 90 bp repeats, each of which contains two Spl elements and lacks a TATA box. The MAOB core promoter region contains two sets of overlapping Spl sites which flank a CACCC element all upstream of a TATA box. The different organization of the MAOA and MAOB promoters may underlie their different cell and tissue specific expression.  相似文献   
8.
9.
The relationship of large and vascularized chorioangiomas to adverse pregnancy outcome is well recognized. We present a patient with a large placental tumor and signs of impending fetal cardiac failure. The angioarchitecture of the tumor depicted by three-dimensional (3D) power Doppler ultrasound enabled us to accurately diagnose a placental chorioangioma. During the follow-up period, quantitative flow data obtained using 3D power Doppler indicated altered hemodynamics in the tumor and concomitant improvement in the condition of the fetus, enabling us to manage the mother conservatively. Spontaneous delivery occurred at 38 weeks without any complications. This report demonstrates the potential value of 3D power Doppler in prenatal diagnosis and monitoring of pregnancies complicated by large, vascularized chorioangioma.  相似文献   
10.
Nuclear Medicine offers screening methods for oncology such as bone and bone marrow scintigraphy. During the last two decades, special procedures have gained widespread application. This paper is centered around the “tumor-specific” radiopharmaceuticals. In patients with thyroid cancer, I-131 still plays a significant role. Ga-67 still has its indications in lymphoma, while in other diseases Tl-201 cloride is now the agent of choice. Especially in thyroid cancer, Tl-201 has proved to be a reliable tumor imaging radiopharmaceutical. More recently, Tc-99m MIBI was introduced for tumor imaging. Tc-99m HMPAO may also be used for tumor scintigraphy, especially in brain lesions. In addition, I-123 IMP has successfully been used for imaging malignant melanoma. Another promising field of tumor diagnosis is receptor imaging. In neuroblastoma and malignant pheochromocytoma, I-131/123 mIBG is the radiopharmaceutical of choice and may be considered as a receptor imaging agent also. First clinical results with In-111 octreotide show potentials as somatostatine-receptor radiopharmaceutical in insulinoma, islet cell carcinoma, medullary and lung cancer, while I-123 estradiol needs some improvement until it may be recommended as diagnostic tool in breast cancer. Since 1978, radiolabeled poly- or monoclonal tumor antibodies and their fragments have gained widespread application. Especially the Tc-99m 225.28S melanoma antibody, I-131 or Tc-99m CEA and In-111/I-131 labeled OC-125 antibodies have proven to be of clinical significance in melanoma, colorectal and ovarian cancer.  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