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   9966篇
  免费   433篇
  国内免费   132篇
耳鼻咽喉   77篇
儿科学   158篇
妇产科学   64篇
基础医学   1092篇
口腔科学   281篇
临床医学   613篇
内科学   2721篇
皮肤病学   145篇
神经病学   664篇
特种医学   421篇
外科学   2117篇
综合类   37篇
预防医学   209篇
眼科学   116篇
药学   548篇
中国医学   16篇
肿瘤学   1252篇
  2024年   4篇
  2023年   75篇
  2022年   118篇
  2021年   278篇
  2020年   162篇
  2019年   180篇
  2018年   229篇
  2017年   184篇
  2016年   241篇
  2015年   249篇
  2014年   361篇
  2013年   433篇
  2012年   667篇
  2011年   708篇
  2010年   393篇
  2009年   339篇
  2008年   619篇
  2007年   648篇
  2006年   647篇
  2005年   704篇
  2004年   685篇
  2003年   633篇
  2002年   618篇
  2001年   109篇
  2000年   79篇
  1999年   124篇
  1998年   165篇
  1997年   119篇
  1996年   118篇
  1995年   79篇
  1994年   73篇
  1993年   74篇
  1992年   48篇
  1991年   45篇
  1990年   37篇
  1989年   48篇
  1988年   34篇
  1987年   24篇
  1986年   27篇
  1985年   18篇
  1984年   20篇
  1983年   19篇
  1982年   7篇
  1981年   11篇
  1980年   8篇
  1979年   12篇
  1978年   11篇
  1977年   7篇
  1975年   8篇
  1974年   8篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
2.
3.
4.
5.
6.
The aim of this study was to evaluate whether the lesion regression rate (ΔLR) based on the Response Evaluation Criteria in Solid Tumors (RECIST) criteria could be used for the prediction of treatment outcome in head and neck squamous cell carcinoma (HNSCC) patients treated with chemoradiotherapy (CRT) compared with FDG PET-CT. A total of 33 patients underwent MRI and PET-CT at pretreatment and at 8 weeks after CRT. We assessed the treatment outcome by analyzing the following parameters: the RECIST criteria, ΔLR, the European Organization for Research and Treatment of Cancer (EORTC) criteria, and pretreatment SUVmax of the primary tumor and node. The correlation between the analysis of the parameters and the results of the long-term follow-up of the patients was determined. The RECIST did not significantly correlate with locoregional control (LRC) or survival. The ΔLR was significantly lower for the lesions with locoregional failure (LRF) than for those with LRC. A threshold ΔLR of 48% revealed a sensitivity of 72.7% and specificity of 77.3% for the prediction of LRF. Progression-free survival (PFS) of patients with ΔLR ≥ 48% was significantly better than that of patients with ΔLR < 48% (P = 0.001), but not overall survival. There was a significant correlation between LRC and the EORTC (P = 0.02). The patients who achieved a complete response by the EORTC criteria showed significantly better PFS and overall survival (P = 0.01 and 0.04, respectively). The ΔLR was inferior to FDG PET-CT with respect to the prediction of patient survival; however, it may be useful for selecting patients in need of more aggressive monitoring after CRT.  相似文献   
7.
A case of cystadenocarcinoma of the liver is reported. The patient was a 73-year-old woman in whom a tumor was detected in the lateral segment of the liver during a health examination. Ultrasonograms and computed tomograms showed a multilocular cystic mass. Magnetic resonance imaging (MRI) showed a multilocular lowintensity mass, including a high-intensity portion and a portal branch compressed by the tumor. MRI with gadolinium showed an enhanced cyst wall. The cystic part of the tumor became smaller and the solid part became larger over a 1-month period, indicating that the tumor was malignant. Subsegmentectomy (S3) was performed and cystadenocarcinoma with cystadenoma was diagnosed by histopathological examination. Identification of changes in the appearance of a tumor should be helpful for the differential diagnosis of cystadenoma and cystadenocarcinoma.  相似文献   
8.
Severe myoclonic epilepsy (SMEI) or Dravet syndrome is caused by mutations of the SCN1A gene that encodes voltage-gated sodium channel alpha-1 subunit. Recently, we generated and characterized a knock-in (KI) mice with an SCN1A nonsense mutation that appeared in three independent SMEI patients. The SCN1A-KI mice well reproduced the SMEI disease phenotypes. Both homozygous and heterozygous knock-in mice developed epileptic seizures within the first postnatal month. In heterozygous knock-in mice, trains of evoked action potentials in inhibitory neurons exhibited pronounced spike amplitude decrement late in the burst but not in pyramidal neurons. We further showed that in wild-type mice the Nav1.1 protein is expressed dominantly in axons and moderately in somata of parbalbumin (PV) – positive inhibitory interneurons. Our immunohistochemical observations of the Nav1.1 are clearly distinct to the previous studies, and our findings has corrected the view of the Nav1.1 protein distribution. The data indicate that Nav1.1 plays critical roles in the spike output from PV interneurons and further, that the specifically altered function of these inhibitory circuits may contribute to epileptic seizures in the mice. These information should contribute to the understanding of molecular pathomechanism of SMEI and to develop its effective therapies.  相似文献   
9.
OBJECTIVE: To evaluate a proposed technique for the 3-dimensional (3D) detection of hemangiomas, including vascular malformation and their feeding arteries, in the head and neck. The new technique combines phase-contrast magnetic resonance angiography (PCMRA) without contrast medium and 3D fast asymmetric spin-echo (FASE) sequences. METHODS: The technique was applied to 3 patients having hemangiomas in the head and neck region. In 1 patient the image obtained with the proposed technique was compared to that obtained by standard contrast angiography. RESULTS: In all 3 patients, the 3D presence of the hemangiomas and the feeding arteries were well defined in images created by the proposed technique. Additionally, the characterization of the hemangioma's 3D structure and distribution of the feeding arteries coincided with those observed using contrast angiography in the case for which contrast angiography was also performed. CONCLUSIONS: Preliminary experience shows that the proposed technique combining 3D-FASE and 3D-PCMRA is useful to visualize both the 3D structure of hemangiomas and to identify the 3D distribution of the feeding arteries without using contrast medium.  相似文献   
10.
Isolated rupture of radial collateral ligament of the small finger DIP joint is a rare injury. We treated this lesion using a bone suture anchor with excellent results.  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