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   76344篇
  免费   6871篇
  国内免费   4442篇
耳鼻咽喉   694篇
儿科学   1623篇
妇产科学   1173篇
基础医学   7240篇
口腔科学   1170篇
临床医学   7022篇
内科学   9678篇
皮肤病学   789篇
神经病学   2220篇
特种医学   3729篇
外国民族医学   52篇
外科学   10626篇
综合类   13331篇
现状与发展   19篇
预防医学   2316篇
眼科学   592篇
药学   5627篇
  51篇
中国医学   2494篇
肿瘤学   17211篇
  2024年   67篇
  2023年   1069篇
  2022年   1839篇
  2021年   3093篇
  2020年   2670篇
  2019年   2364篇
  2018年   2193篇
  2017年   2411篇
  2016年   2809篇
  2015年   3108篇
  2014年   5096篇
  2013年   4954篇
  2012年   4572篇
  2011年   4876篇
  2010年   4001篇
  2009年   4054篇
  2008年   4165篇
  2007年   4412篇
  2006年   4015篇
  2005年   3527篇
  2004年   2871篇
  2003年   2454篇
  2002年   2250篇
  2001年   2057篇
  2000年   1718篇
  1999年   1496篇
  1998年   1214篇
  1997年   1112篇
  1996年   982篇
  1995年   934篇
  1994年   789篇
  1993年   624篇
  1992年   503篇
  1991年   440篇
  1990年   351篇
  1989年   333篇
  1988年   299篇
  1987年   255篇
  1986年   195篇
  1985年   252篇
  1984年   214篇
  1983年   133篇
  1982年   187篇
  1981年   149篇
  1980年   124篇
  1979年   131篇
  1978年   88篇
  1977年   66篇
  1976年   59篇
  1975年   25篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
《Molecular therapy》2022,30(1):485-500
  1. Download : Download high-res image (207KB)
  2. Download : Download full-size image
  相似文献   
2.
3.
外泌体是一类直径为30~100 nm的圆盘囊泡,其内包含许多组分,诸如复杂RNA和蛋白质等,主要参与细胞间的信号转导。肿瘤相关巨噬细胞(tumor-associated macrophages,TAMs)是肿瘤微环境中普遍存在的巨噬细胞,通过对肿瘤生长、免疫逃逸、侵袭和转移、耐药性等多方面的作用影响肿瘤进程。外泌体在肿瘤相关巨噬细胞的招募、极化及抗肿瘤免疫调控等方面发挥着重要的调节功能。同时,TAMs以外泌体为媒介作用于肿瘤细胞,从而构成了外泌体、TAMs与肿瘤细胞之间相互作用的调控通路。综上所述,本文旨在阐明肿瘤细胞与TAMs之间,以外泌体为“桥梁”相互影响的潜在机制,以及靶向肿瘤细胞和TAMs来源的外泌体在恶性肿瘤治疗中的展望。  相似文献   
4.
5.
BackgroundCentrally located pancreatic lesions are often treated with extended pancreaticoduodenectomy or distal pancreatectomy resulting in loss of healthy parenchyma and a high risk of diabetes and exocrine insufficiency. Robotic central pancreatectomy (RCP) is a parenchyma sparring alternative that has been shown safe and feasible [[1], [2]].MethodsIn this article, we describe our operative technique and the perioperative outcomes of a series of RCP for low-grade or benign pancreatic tumors.ResultsSix patients (5 female and 1 man) with a median age of 51.5 (44–68) years underwent a RCP for 2 serous cystadenomas, 2 mucinous cystic tumors, 1 neuroendocrine tumor, and 1 autoimmune pancreatitis. There were no conversions, intraoperative complications, or perioperative transfusions. Median operative time and was 240 (230–291) minutes and median blood loss was 100 (100–400) ml. The median hospital stay was 8 (5–27) days. There were no mortalities, reoperations, or readmissions. One patient developed a grade B pancreatic fistula which was successfully managed conservatively. All resections had free margins and the median tumor size was 2.5 (1.5–3.5) cm. After a mean follow-up of 46 months, no patients presented new-onset diabetes or exocrine insufficiency.ConclusionsRCP represents the least invasive option for both the patient and the pancreatic parenchyma. With a standardized technique, RCP results in low postoperative morbidity and excellent long-term pancreatic function. Although our results are excellent, POPF still represents the main complication of central pancreatectomy with an incidence ranging from 0 to 80% depending on multiple factors such as the surgeon, technique, and pancreatic texture.  相似文献   
6.
In clear cell renal cell carcinoma (ccRCC), glycolysis is enhanced mainly because of the increased expression of key enzymes in glycolysis. Hence, the discovery of new molecular biomarkers for glycolysis may help guide and establish a precise system of diagnosis and treatment for ccRCC. Expression profiles of 1079 tumor samples of ccRCC patients (including 311 patients treated with everolimus or nivolumab) were downloaded from public databases. Proteomic profiles of 232 ccRCC samples were obtained from Fudan University Shanghai Cancer Center (FUSCC). Biological changes, tumor microenvironment and prognostic differences were explored between samples with various glycolysis characteristics. There were significant differences in CD8+ effector T cells, epithelial-to-mesenchymal transition and pan-fibroblast TGFb between the Low and High glyScore groups. The tumor mutation burden of the Low glyScore group was lower than that of the High glyScore group. And higher glyScore was significantly associated with worse overall survival (OS) in 768 ccRCC patients (P < .0001). External validation in FUSCC cohort also indicated that glyScore was of strong ability for predicting OS (P < .05). GlyScore may serve as a biomarker for predicting everolimus response in ccRCC patients due to its significant associations with progression-free survival (PFS). And glyScore may also predict overall survival in patients treated with nivolumab. We calculated the glyScore in ccRCC and the defined glyScore was of strong ability for predicting OS. In addition, glyScore may also serve as a biomarker for predicting PFS in patients treated with everolimus and could predict OS in patients treated with nivolumab.  相似文献   
7.
8.
《Clinical lung cancer》2022,23(3):191-194
BackgroundTo accelerate drug approvals while maintaining scientific rigor in the evaluation of a therapeutic's efficacy and safety, the United States Food and Drug Administration now considers real-world data (RWD) to support New Drug Applications and expanded indications. Response Evaluation Criteria in Solid Tumors (RECIST) are the gold standard in clinical trials, but the derivation of RECIST-based treatment response from RWD is unproven. This study investigated the feasibility of implementing RECIST criteria in RWD by comparing lung cancer response assessments from RECIST-based measurement of lesions on archived radiologic films with results from medical oncologist and radiologist narratives recorded in electronic health records (EHR).Materials and MethodsResponse to index treatment via different assessment approaches was compared among 30 metastatic non-small cell lung cancer (mNSCLC) patients receiving systemic treatment (index) after progression on a platinum or anti-PD(L)-1-containing regimen. Specifically, responses based on assessments documented in the medical oncologists’ narratives were compared to a radiologist's assessments of archived images using RECIST v1.1 criteria. Each patient's best overall response was characterized as complete or partial (CR/PR), stable disease (SD), progressive disease (PD), or not evaluable (NE).ResultsSimilar distributions of best overall response and substantial concordance (77%) between medical oncologist-reported and radiologist re-assessed responses were observed. There were no instances of CR/PR to PD or PD to CR/PR discordance.ConclusionsResults suggest that accurate treatment responses, similar to RECIST, may be derived using RWD. Further validation and improvement of real-world response assessment are needed to develop a scalable real-world approach for response assessment.  相似文献   
9.
Background: The current disadvantages (high cost, toxicity, resistance) of chemotherapy for gastric cancer opted people for alternative therapy from natural source. Curcumin (natural product) possess multiple biological activities but low bio-availability limits their uses as therapeutic. The Nano-formulation of curcumin increased the bioavailability and productivity of anti-cancer and anti-bacterial properties. The present study was initiated to determine the anti-cancer and anti-bacterial effect of Nano curcumin against gastric cancer and H. pylori. Methods: Curcumin loaded PLGA nanoparticles (CUR-NPs) was prepared by single emulsion solvent evaporation method. The MIC were determined using agar dilution method to find the anti-H. Pylori activity of Nano curcumin. The cytotoxicity of Nano curcumin was evaluated by MTT assay and the apoptotic effect (cell cycle arrest and morphology change) was shown by PI staining and microscopy. Results: The MIC of nanocurcumin and curcumin for all four H. pylori strains were 8 µg/ml and 16 µg/ml respectively. The inhibition rate of gastric cancer cells after treatment with curcumin was increased from 6% to 67% for 24h, from 8% to 75% for 48h, from 10% to 83% for 72h. In case of nanocurcumin, the inhibition rate increased from 7% to 69% for 24h, 11% to 87% for 48h and 16% to 97% for 72h. The IC50 of curcumin and Nano-curcumin were 24.20 µM and 18.78 µM respectively for 72 h. The population of cells in sub-G0 population increased from 4.1% in the control group to 24.5% and 57.8% when treated with curcumin and nanocurcumin respectively. After 72h of treatment with nanocurcumin, the apoptotic cells population increased as compared to native curcumin treated cells. Conclusion: The Nano curcumin might be used as a potential therapeutics against gastric cancer and H. Pylori. There is need of further in vivo study in order to validate CUR-NPs activity.  相似文献   
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