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   4884篇
  免费   350篇
  国内免费   21篇
耳鼻咽喉   68篇
儿科学   210篇
妇产科学   115篇
基础医学   767篇
口腔科学   141篇
临床医学   355篇
内科学   1260篇
皮肤病学   134篇
神经病学   376篇
特种医学   265篇
外科学   680篇
综合类   27篇
一般理论   3篇
预防医学   230篇
眼科学   108篇
药学   258篇
中国医学   12篇
肿瘤学   246篇
  2023年   15篇
  2022年   38篇
  2021年   127篇
  2020年   64篇
  2019年   129篇
  2018年   141篇
  2017年   81篇
  2016年   91篇
  2015年   113篇
  2014年   150篇
  2013年   188篇
  2012年   287篇
  2011年   301篇
  2010年   183篇
  2009年   185篇
  2008年   261篇
  2007年   254篇
  2006年   243篇
  2005年   247篇
  2004年   245篇
  2003年   234篇
  2002年   197篇
  2001年   188篇
  2000年   203篇
  1999年   148篇
  1998年   79篇
  1997年   78篇
  1996年   84篇
  1995年   51篇
  1994年   43篇
  1993年   53篇
  1992年   67篇
  1991年   47篇
  1990年   51篇
  1989年   36篇
  1988年   35篇
  1987年   53篇
  1986年   35篇
  1985年   24篇
  1984年   24篇
  1983年   21篇
  1982年   27篇
  1981年   10篇
  1980年   12篇
  1979年   12篇
  1977年   18篇
  1976年   13篇
  1975年   15篇
  1971年   7篇
  1970年   7篇
排序方式: 共有5255条查询结果,搜索用时 19 毫秒
1.
2.
Gray platelet syndrome (GPS) is a rare (<1/1 000 000) and inherited platelet function disorder characterized by macrothrombocytopenia, α-granule deficiency, and hemorrhages. Bleeding intensity does not correlate with platelet count nor with functional test results. We hereby describe the perioperative bleeding prevention and management of a patient with GPS requiring multiple redo cardiac surgeries.  相似文献   
3.
4.
5.
Cidofovir is an acyclic nucleoside phosphonate with broad-spectrum activity against DNA viruses, including human papilloma virus (HPV). However, data on the efficacy of cidofovir in an immunosuppressive setting remain contradictory. We report for the first time on the promotion of the healing of recalcitrant warts in a patient with myelodysplastic syndrome with intravenous cidofovir treatment.  相似文献   
6.
Many types of seafood require cooking before ingestion and it has been demonstrated that this cooking process may affect the antigenicity and allergenicity of the food. We describe a case of anaphylaxis caused by selective sensitization to razor shell, a mollusc. In vivo and in vitro studies confirmed sensitization to boiled razor shell. Analysis of the nature of the allergen yielded results that were consistent with the findings of other authors and suggested that allergens involved in seafood allergy are commonly high molecular weight proteins that, in most cases, are heat stable.  相似文献   
7.
8.
Laparoscopic pancreatic surgery (LPS) has seen significant development but much of the knowledge refers to small and benign pancreatic tumors. This study aims to evaluate the feasibility, safety, and long-term outcome of the laparoscopic approach in patients with benign, premalignant, and overt malignant lesions of the pancreas. This study, currently, is the largest single center experience worldwide. One hundred twenty-three consecutive patients underwent laparoscopic pancreatic surgery from April 1998 to April 2007, 20 patients with cysts or pseudocysts for acute and chronic pancreatitis, laparoscopic pancreatic drainage was performed, and were excluded from the analysis. The 103 patients were divided based on preoperative diagnosis: group I, inflammatory tumors for chronic pancreatitis (eight patients); group II, cystic pancreatic neoplasms (29 patients); group III, intraductal papillary mucinous neoplasms (10 patients); group IV, neuroendocrine pancreatic tumors (NETs) (43 patients); and group V ductal adenocarcinoma (13 patients). The median tumor size was 5.3 cm. Pathologic data include R 0 or R 1 resection (transection margins on the specimen were inked). Perioperative data, postoperative complications, and resection modalities were compared using statistical analysis. Long-term outcomes were analysed by tumor recurrence and patient survival. The overall conversion rate was 7%. Laparoscopic distal pancreatic resection was performed in 82 patients (79.6%). Laparoscopic spleen-preserving distal pancreatectomy (Lap SPDP) was performed in 52 patients (63.7%), but with splenic vessels preservation in 22% and without splenic vessels preservation in 41.5%. Laparoscopic en-bloc splenopancreatectomy (Lap SxDP) was performed in 30 patients (36.6%) and laparoscopic enucleation (Lap En) in 20 patients (19.4%). There was no mortality. The overall complication rate was 25.2, 16.7, and 40% after Lap SPDP, Lap SxDP, and Lap En, respectively. The overall morbidity rate was significantly higher (p > 0.05) in the group of Lap SPDP without splenic vessels preservation comparing with Lap SPDP with splenic vessels preservation because of the occurrence of splenic complications (20.6%). The overall pancreatic fistulas was 7.7, 10, and 35% after Lap SPDP, Lap SxDP, and Lap En, respectively; the severity of fistula was significantly higher in the Lap En group (p > 0.05). The mean hospital stay was within 1 week in all groups, except in the group of ductal adenocarcinoma, which is 8 days. In this series, 27 patients (26.2%) had malignant disease. R 0 resection was achieved in 90% of ductal adenocarcinoma and 100% for other malignant tumors. The median survival for ductal adenocarcinoma patients was 14 months. This series demonstrates that LPS is feasible and safe in benign-appearing and malignant lesions of the pancreas.  相似文献   
9.
Poly(epsilon-caprolactone) microspheres containing bupivacaine were prepared by the spray-drying process. The average size of drug loaded microspheres was less than 3 microm in diameter, and the percentage of entrapment efficiency was 91 +/- 3%. In vitro drug release kinetic in phosphate buffer at 37 degrees C showed a hyperbolic profile, with a burst-effect during the first hour. Subcutaneous injection of bupivacaine-loaded microspheres in the back of rats caused an increase in drug concentration in plasma. Maximum bupivacaine concentration in plasma was 237 +/- 58 ng/ml at 105 h, and drug was detected in plasma for 16 days. The half-life time of the drug was increased by more than 125 times with regard to that of the drug administered in a solution by intraperitoneal injection. After 30 days of injection, a mass formed by microspheres surrounded by a thin fibrous capsule was observed. Small blood vessels and multinucleate foreign body giant cells with macrophagic function around microspheres were detected. After 60 days of injection a subcutaneous mass was also observed, which was formed of more degraded dispersed microspheres in conjunctive tissue, which had a normal structure. Thus, bupivacaine-loaded poly(epsilon-caprolactone) microspheres could be considered as a device to be used in the treatment of severe pain that is not responsive to opioids for example in cancer-related syndromes or in intractable herpetic neuralgia.  相似文献   
10.
Background and objectiveTo analyse frequency, characteristics and patient survival with lung cancer (LC) and Common Obstructive Pulmonary Disease (COPD), comparing them with patients that do not have COPD.Material and methodsA retrospective study, of patients diagnosed by means of cytohistology. Survival was estimated by the Kaplan-Meier method. Statistical analysis was carried out using SPSS 15.0.ResultsA total of 996 patients were diagnosed, 39.8% with COPD. Mean age70±9.19 years. GOLD stages: I 18.2%, II 53.6%, III 24%, IV 4.2%. The histological types: squamous cell carcinoma 48.2%, adenocarcinoma 22%, and small cell carcinoma 22.5%. Survival was longer in the COPD group.ConclusionsLC and COPD are combined in 39.8%. Squamous cell type is more frequent and survival was longer in the COPD group.  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