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   3890篇
  免费   158篇
  国内免费   32篇
耳鼻咽喉   34篇
儿科学   34篇
妇产科学   40篇
基础医学   490篇
口腔科学   84篇
临床医学   269篇
内科学   1193篇
皮肤病学   28篇
神经病学   314篇
特种医学   143篇
外科学   511篇
综合类   11篇
预防医学   73篇
眼科学   202篇
药学   195篇
中国医学   7篇
肿瘤学   452篇
  2024年   7篇
  2023年   23篇
  2022年   37篇
  2021年   58篇
  2020年   40篇
  2019年   53篇
  2018年   81篇
  2017年   68篇
  2016年   57篇
  2015年   70篇
  2014年   100篇
  2013年   125篇
  2012年   245篇
  2011年   284篇
  2010年   146篇
  2009年   151篇
  2008年   253篇
  2007年   279篇
  2006年   267篇
  2005年   270篇
  2004年   280篇
  2003年   229篇
  2002年   224篇
  2001年   51篇
  2000年   75篇
  1999年   86篇
  1998年   55篇
  1997年   32篇
  1996年   32篇
  1995年   32篇
  1994年   30篇
  1993年   20篇
  1992年   37篇
  1991年   35篇
  1990年   30篇
  1989年   46篇
  1988年   23篇
  1987年   15篇
  1986年   10篇
  1985年   13篇
  1984年   10篇
  1983年   12篇
  1982年   8篇
  1981年   7篇
  1979年   13篇
  1978年   7篇
  1975年   10篇
  1972年   5篇
  1970年   5篇
  1966年   6篇
排序方式: 共有4080条查询结果,搜索用时 11 毫秒
21.
22.
23.
24.
We describe herein the case of a 51-year-old woman in whom metastatic tumor seeding of the percutaneous transhepatic biliary drainage tract occurred following a pancreatoduodenectomy for carcinoma of the distal common bile, duct. An abdominal computed tomography scan done 6 months after the initial operation detected a hepatic lesion located at the site of the previous percutaneous transhepatic biliary drainage tract. Implantation of bile duct carcinoma in the drainage tract was diagnosed, and the recurrent tumor was successfully resected by performing a subsegmentectomy of segment 3 and removal of the adjacent abdominal wall. At present, 5 years and 4 months after the second resection, the patient is in good health without any signs of recurrence. This case report demonstrates that an aggressive surgical approach should be performed for tumor seeding of a transhepatic biliary catheter tract.  相似文献   
25.
OBJECTIVE: The purpose of this study was to clarify the nature of Osgood-Schlatter disease (OSD) using MR images.DESIGN: Thirty boys (40 knees) with OSD diagnosed by clinical symptoms and signs were investigated with MRI. Longitudinal evaluation was undertaken in 22 patients and the mean follow-up was 1.5+/-0.9 years. MR examinations were performed at least every 6 months in most cases. When a patient's symptoms changed, MRI was repeated and in cases where the initial MR examination showed an early or progressive stage of OSD, MRI was undertaken every month where possible. All MR examinations were performed in the sagittal plane with a 0.2 T imager.RESULTS: MR images were classified into five stages as follows: normal, early, progressive, terminal and healing. The stage of 11 knees (28%) did not change during the course of the study and 21 knees (53%) showed a change of at least one stage. Eight knees (20%) did not have follow-up MR studies. The initial MR examination was normal in nine knees. Eight knees were at the early stage at presentation. MR images showed edema-like changes around the tibial tuberosity. Ten knees were classified as in the progressive stage at the initial presentation and six knees were classified in this group during progression on follow-up MRI. MR images showed partial avulsion of the secondary ossification center, which was seen to be being pulled proximally. Eleven knees were at the terminal stage on presentation, where the avulsed parts of the secondary ossification center had become completely separated. Two knees were classified as in the healing stage at presentation and 19 knees progressed to the healing stage from the normal, early and progressive stages. The MR images showed the separated part that did not create the ossicle had recovered by osseous healing. On the other hand, radiographs of the early stage appeared almost normal, and in the progressive stage could not show the avulsed parts.CONCLUSIONS: We clarified the progress of OSD with MRI. The process of OSD started from the apophyseal stage and a tear appeared in the secondary ossification center, widening to an opened shell-like shape. This damage progressed to an ossicle in some cases. In short, the ossicle was formed from an avulsed portion. It was very difficult to show the course of OSD with radiography. MR images were especially useful for revealing early and progressive lesions of OSD.  相似文献   
26.

Purpose  

Laparoscopic colonic surgery is now widely accepted. We assessed the safety and effectiveness of using a total intracorporeal surgical strategy to perform intracorporeal functional end-to-end anastomosis with an endoscopic linear stapler to treat colon cancer.  相似文献   
27.
Stroke leaves serious neurological sequelae, which require long-term medical and social care, imposing financial and mental burdens on the patients and their families, and causing enormous losses to society. It is currently required that medical resources be used efficiently and the cost-effectiveness of treatment be analyzed carefully. We conducted a follow-up survey of stroke patients admitted to the hospital attached to our university in order to build a picture of the current status of chronic-phase stroke medical treatment. In total, 330 patients were analyzed in this study. We evaluated utility and medical cost at one year after onset. To investigate the relationship between activities of daily living (ADL) classified according to the modified Rankin scale (mRS) and quality of life (QOL), utility was calculated for each ADL level. Utility at 1 year post-onset for each mRS level was: ADL0, 0.89; ADL1, 0.79; ADL2, 0.65; ADL3, 0.58; ADL4, 0.36; and ADL5, 0.09. A significant correlation was seen between utility and mRS. Direct monthly medical costs at 1 year post-onset were 61,536 yen in the ADL0 group and 383,444 yen in the ADL5 group, indicating that a worse ADL score required higher medical costs. Direct monthly costs were significantly different between ADL levels. This present study has clarified the QOL and medical costs of chronic-phase stroke patients, and many cost-utility analyses will be based on our data in the future in Japan.  相似文献   
28.
Osteoclasts are formed from the monocyte-macrophage lineage in response to receptor activator of nuclear factor κB ligand (RANKL) expressed by osteoblasts. Bone is the most common site of breast cancer metastasis, and osteoclasts play roles in the metastasis. The taxane-derived compounds paclitaxel and docetaxel are used for the treatment of malignant diseases, including breast cancer. Here we explored the effects of docetaxel on osteoclastic bone resorption in mouse culture systems. Osteoclasts were formed within 6 days in cocultures of osteoblasts and bone marrow cells treated with 1,25-dihydroxyvitamin D3 plus prostaglandin E2. Docetaxel at 10−8 M inhibited osteoclast formation in the coculture when added for the entire culture period or for the first 3 days. Docetaxel, even at 10−6 M added for the final 3 days, failed to inhibit osteoclast formation. Osteoprotegerin, a decoy receptor of RANKL, completely inhibited osteoclast formation when added for the final 3 days. Docetaxel at 10−8 M inhibited the proliferation of osteoblasts and bone marrow cells. RANKL mRNA expression induced by 1,25-dihydroxyvitamin D3 plus prostaglandin E2 in osteoblasts was not affected by docetaxel even at 10−6 M. Docetaxel at 10−6 M, but not at 10−8 M, inhibited pit-forming activity of osteoclasts cultured on dentine. Actin ring formation and l-glutamate secretion by osteoclasts were also inhibited by docetaxel at 10−6 M. Thus, docetaxel inhibits bone resorption in two different manners: inhibition of osteoclast formation at 10−8 M and of osteoclast function at 10−6 M. These results suggest that taxanes have beneficial effects in the treatment of bone metastatic cancers. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
29.
The Airway Scope (AWS) is a new videolaryngoscope which consists of an optical system and a single-use blade. The blade of the device is designed according with the pharyngeal anatomy, and thus the AWS is expected to have a role in the management of difficult airway. We here report 15 patients with difficult airway in whom the AWS provided in successful intubation. The AWS provides a view of the glottis with Cormack-Lehane grade 1 and resulted in successful intubation in the 15 patients. The AWS is useful for the management of difficult airway.  相似文献   
30.
Whereas fibrous dysplasia is a well-known, developmental skeletal disorder with a benign clinical course, fibrous dysplasia of the clivus is extremely rare and has seldom been reported. Differentiating this benign entity from more aggressive diseases involving the clivus is important for the proper management of lesions in this area. We here report a case of fibrous dysplasia of the clivus and discuss its radiographic features. The patient was 55-year-old male who had suffered from headache for months. Physical and neurological examinations found no abnormalities. The computed tomographic (CT) scan and magnetic resonance imaging (MRI) showed an abnormal mass lesion in the lower of the third clivus. On CT scan, the mass lesion exhibited a ground-glass appearance. The lesion was detected as hypointense and a mixture of hyperintense and isointense areas on T1-weighted and T2-weighted MRI, respectively. Heterogenous enhancement was noted after infusion of GD-DTPA. The patient underwent a transsphenoidal resection of the mass and the histopathologic diagnosis was fibrous dysplasia.  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