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   9852篇
  免费   692篇
  国内免费   44篇
耳鼻咽喉   94篇
儿科学   374篇
妇产科学   146篇
基础医学   1414篇
口腔科学   147篇
临床医学   870篇
内科学   1823篇
皮肤病学   198篇
神经病学   1127篇
特种医学   471篇
外国民族医学   5篇
外科学   1460篇
综合类   71篇
一般理论   6篇
预防医学   515篇
眼科学   227篇
药学   961篇
  1篇
中国医学   4篇
肿瘤学   674篇
  2021年   112篇
  2019年   96篇
  2018年   142篇
  2017年   97篇
  2016年   143篇
  2015年   170篇
  2014年   179篇
  2013年   271篇
  2012年   377篇
  2011年   430篇
  2010年   214篇
  2009年   204篇
  2008年   351篇
  2007年   407篇
  2006年   411篇
  2005年   362篇
  2004年   424篇
  2003年   397篇
  2002年   322篇
  2001年   339篇
  2000年   333篇
  1999年   271篇
  1998年   116篇
  1997年   120篇
  1996年   121篇
  1995年   92篇
  1994年   82篇
  1993年   89篇
  1992年   220篇
  1991年   224篇
  1990年   216篇
  1989年   253篇
  1988年   229篇
  1987年   214篇
  1986年   196篇
  1985年   215篇
  1984年   139篇
  1983年   104篇
  1982年   92篇
  1981年   89篇
  1980年   90篇
  1979年   144篇
  1978年   92篇
  1977年   86篇
  1976年   115篇
  1975年   103篇
  1974年   96篇
  1972年   74篇
  1971年   87篇
  1970年   83篇
排序方式: 共有10000条查询结果,搜索用时 62 毫秒
91.
Interventions for parvovirus B19 infection need to balance the low risk of infection at a population level with the potential for serious adverse outcome for particular groups, notably the fetus, people with haemoglobinopathies and the immunocompromised. This guidance aims to assist the local decision-making process to be as evidence-based as the available evidence allows.  相似文献   
92.
Metabolism and excretion of atorvastatin in rats and dogs.   总被引:1,自引:0,他引:1  
Atorvastatin (AT) is a second-generation potent inhibitor of 3-hydroxy-3-methylglutaryl-CoA reductase, clinically approved for lowering plasma cholesterol. Using a mixture of [D(5)/D(0)] AT and/or [(14)C]AT, the metabolic fate and excretion of AT were examined in rats and dogs following single and multiple oral doses. Limited biliary recycling was examined in one dog after a single dose of AT. AT-derived metabolites in bile samples were identified by metabolite screening of the [D(5)/D(0)] AT molecular clusters using tandem mass spectrometry. Bile was a major route of [(14)C] drug-derived excretion, accounting for 73 and 33% of the oral dose in the rat and dog, respectively. The remaining radioactivity was recovered in the feces; only trace amounts were excreted in urine. Radioactive components identified in rat and dog bile were the para- and ortho-hydroxy metabolites, a glucuronide conjugate of ortho-hydroxy AT, and unchanged AT. Two minor radioactive components were identified as beta-oxidation products of AT with one confirmed as a beta-oxidized AT derivative. The reappearance of AT and major metabolites in bile from a dog administered a sample of its previously excreted bile indicated biliary recycling is an important component in AT metabolism. Multiple dose administration in rats did not alter biliary metabolic profiles. Rat and dog plasma profiles after multiple dose administration were similar and showed no additional metabolites not found in bile. Examination of rat and dog bile and plasma indicates that AT primarily undergoes oxidative metabolism.  相似文献   
93.
94.
95.
96.
Twenty-two consecutive patients (23 wrists) underwent open reduction internal fixation of dorsal perilunate dislocations and fracture-dislocations through combined dorsal and volar approaches. One of 5 experienced wrist surgeons performed these procedures within an average of 3 days of injury (range, 0-26 days) and intercarpal fixation was kept within the proximal carpal row. Motion was instituted an average of 10 weeks (range, 5-16 weeks) after injury. All patients were males. The average age at the time of injury was 32 years (range, 16-60 years). The average follow-up period was 37 months (range, 13-65 months). Average flexion-extension motion arc and grip strength in the injured wrist were 57% and 73%, respectively, compared with the contralateral wrist. The scapholunate angle increased and the revised carpal height ratio decreased over time, which was statistically significant for both measurements. Three patients (3 wrists) required wrist arthrodesis and a fourth patient had an immediate scaphoid excision and 4-corner arthrodesis secondary to an irreparable scaphoid fracture. One patient required a proximal row carpectomy to treat septic arthritis. Nine of the remaining 18 wrists had radiographic evidence of arthritis, most often at the capitolunate or scaphocapitate articulations. Short form-36 mental summary scores were significantly greater than age- and gender-matched US population values; physical summary scores were significantly less. The disabilities of arm, shoulder, and hand evaluation, Mayo wrist score, and patient-rated wrist evaluation all reflected loss of function. Seventy-three percent of all patients had returned to full duties in their usual occupations and a total of 82% were employed.  相似文献   
97.
98.
99.
PURPOSE: Preclinical studies indicate positive interactions between capecitabine, an oral fluorouracil precursor, and gemcitabine, the current standard treatment for advanced pancreatic carcinoma (APC). In this study, we investigated the addition of capecitabine to gemcitabine treatment for patients with APC. PATIENTS AND METHODS: This multicenter study included patients na?ve to chemotherapy who had histologically or cytologically confirmed, nonresectable or metastatic pancreatic carcinoma. Gemcitabine was given at a fixed dose of 1,000 mg/m(2) on days 1 and 8 of a 21-day cycle. Capecitabine was given in increasing doses orally bid for 14 days followed by a 1-week rest. The maximum-tolerated dose (MTD) was defined as one dose level below the dose causing dose-limiting toxicity (DLT) in >or= one third of a cohort of six patients. We included an additional 15 patients at the MTD. RESULTS: Thirty-six patients were included. DLT occurred at a dose of 800 mg/m(2) bid of capecitabine and consisted of myelotoxicity and mucositis. Hand-foot syndrome was not observed, and other toxic effects were mild. Thus, in this regimen, the recommended dose of capecitabine is 650 mg/m(2) bid. In 27 patients with measurable disease, we observed one complete and four partial remissions. In addition, significant drops (> 50% from baseline value) of the tumor marker CA 19-9 occurred in 14 of 24 assessable patients. CONCLUSION: The combination of capecitabine and gemcitabine is well tolerated, with apparent efficacy in patients with APC. Therefore, it is currently being compared with gemcitabine monotherapy in a phase III study.  相似文献   
100.
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