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   54863篇
  免费   5811篇
  国内免费   91篇
耳鼻咽喉   748篇
儿科学   1576篇
妇产科学   1538篇
基础医学   8486篇
口腔科学   1252篇
临床医学   7068篇
内科学   10349篇
皮肤病学   721篇
神经病学   4480篇
特种医学   1679篇
外国民族医学   1篇
外科学   7181篇
综合类   1178篇
一般理论   38篇
预防医学   5751篇
眼科学   860篇
药学   4534篇
中国医学   89篇
肿瘤学   3236篇
  2021年   807篇
  2020年   512篇
  2019年   840篇
  2018年   969篇
  2017年   699篇
  2016年   889篇
  2015年   932篇
  2014年   1238篇
  2013年   2004篇
  2012年   2686篇
  2011年   2785篇
  2010年   1553篇
  2009年   1402篇
  2008年   2412篇
  2007年   2517篇
  2006年   2457篇
  2005年   2397篇
  2004年   2301篇
  2003年   2213篇
  2002年   2277篇
  2001年   1813篇
  2000年   1792篇
  1999年   1578篇
  1998年   710篇
  1997年   620篇
  1996年   539篇
  1995年   560篇
  1994年   509篇
  1993年   472篇
  1992年   1275篇
  1991年   1189篇
  1990年   1151篇
  1989年   1056篇
  1988年   996篇
  1987年   1024篇
  1986年   979篇
  1985年   984篇
  1984年   798篇
  1983年   691篇
  1982年   504篇
  1981年   434篇
  1980年   431篇
  1979年   653篇
  1978年   501篇
  1977年   415篇
  1976年   430篇
  1974年   441篇
  1973年   387篇
  1972年   397篇
  1971年   347篇
排序方式: 共有10000条查询结果,搜索用时 500 毫秒
1.
2.
3.
4.
5.

Objective

Comparative survival between neoadjuvant chemotherapy and adjuvant chemotherapy for patients with cT2-4N0-1M0 non–small cell lung cancer has not been extensively studied.

Methods

Patients with cT2-4N0-1M0 non–small cell lung cancer who received platinum-based chemotherapy were retrospectively identified. Exclusion criteria included stage IV disease, induction radiotherapy, and targeted therapy. The primary end point was disease-free survival. Secondary end points were overall survival, chemotherapy tolerance, and ability of Response Evaluation Criteria In Solid Tumors response to predict survival. Survival was estimated using the Kaplan–Meier method, compared using the log-rank test and Cox proportional hazards models, and stratified using matched pairs after propensity score matching.

Results

In total, 330 patients met the inclusion criteria (n = 92/group after propensity-score matching; median follow-up, 42 months). Five-year disease-free survival was 49% (95% confidence interval, 39-61) for neoadjuvant chemotherapy versus 48% (95% confidence interval, 38-61) for adjuvant chemotherapy (P = .70). On multivariable analysis, disease-free survival was not associated with neoadjuvant chemotherapy or adjuvant chemotherapy (hazard ratio, 1.1; 95% confidence interval, 0.64-1.90; P = .737), nor was overall survival (hazard ratio, 1.21; 95% confidence interval, 0.63-2.30; P = .572). The neoadjuvant chemotherapy group was more likely to receive full doses and cycles of chemotherapy (P = .014/0.005) and had fewer grade 3 or greater toxicities (P = .001). Response Evaluation Criteria In Solid Tumors response to neoadjuvant chemotherapy was associated with disease-free survival (P = .035); 15% of patients receiving neoadjuvant chemotherapy (14/92) had a major pathologic response.

Conclusions

Timing of chemotherapy, before or after surgery, is not associated with an improvement in overall or disease-free survival among patients with cT2-4N0-1M0 non–small cell lung cancer who undergo complete surgical resection.  相似文献   
6.
Hepatic NADPH-cytochrome P450 oxidoreductase null (HRN?) mice exhibit normal hepatic and extrahepatic biotransformation enzyme activities when compared to wild-type (WT) mice, but express no functional hepatic cytochrome P450 activities. When incubated in vitro with [14C]-diclofenac, liver microsomes from WT mice exhibited extensive biotransformation to oxidative and glucuronide metabolites and covalent binding to proteins was also observed. In contrast, whereas glucuronide conjugates and a quinone-imine metabolite were formed when [14C]-diclofenac was incubated with HRN? mouse liver, only small quantities of P450-derived oxidative metabolites were produced in these samples and covalent binding to proteins was not observed. Livers from vehicle-treated HRN? mice exhibited enhanced lipid accumulation, bile duct proliferation, hepatocellular degeneration and necrosis and inflammatory cell infiltration, which were not present in livers from WT mice. Elevated liver-derived alanine aminotransferase, glutamate dehydrogenase and alkaline phosphatase activities were also observed in plasma from HRN? mice. When treated orally with diclofenac for 7 days, at 30 mg/kg/day, the severities of the abnormal liver histopathology and plasma liver enzyme findings in HRN? mice were reduced markedly. Oral diclofenac administration did not alter the liver histopathology or elevate plasma enzyme activities of WT mice. These findings indicate that HRN? mice are valuable for exploration of the role played by hepatic P450s in drug biotransformation, but poorly suited to investigations of drug-induced liver toxicity. Nevertheless, studies in HRN? mice could provide novel insights into the role played by inflammation in liver injury and may aid the evaluation of new strategies for its treatment.  相似文献   
7.
8.
9.
10.
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