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   3926篇
  免费   294篇
  国内免费   285篇
耳鼻咽喉   19篇
儿科学   27篇
妇产科学   59篇
基础医学   526篇
口腔科学   75篇
临床医学   500篇
内科学   714篇
皮肤病学   17篇
神经病学   237篇
特种医学   129篇
外国民族医学   7篇
外科学   328篇
综合类   598篇
现状与发展   1篇
预防医学   205篇
眼科学   100篇
药学   406篇
  1篇
中国医学   161篇
肿瘤学   395篇
  2024年   13篇
  2023年   74篇
  2022年   183篇
  2021年   227篇
  2020年   153篇
  2019年   129篇
  2018年   118篇
  2017年   121篇
  2016年   103篇
  2015年   175篇
  2014年   209篇
  2013年   194篇
  2012年   302篇
  2011年   305篇
  2010年   165篇
  2009年   136篇
  2008年   195篇
  2007年   184篇
  2006年   182篇
  2005年   216篇
  2004年   130篇
  2003年   152篇
  2002年   104篇
  2001年   75篇
  2000年   91篇
  1999年   91篇
  1998年   69篇
  1997年   71篇
  1996年   41篇
  1995年   43篇
  1994年   34篇
  1993年   28篇
  1992年   21篇
  1991年   32篇
  1990年   18篇
  1989年   21篇
  1988年   12篇
  1987年   13篇
  1986年   13篇
  1985年   3篇
  1984年   8篇
  1983年   9篇
  1982年   4篇
  1981年   10篇
  1980年   2篇
  1979年   7篇
  1978年   3篇
  1976年   3篇
  1971年   3篇
  1967年   3篇
排序方式: 共有4505条查询结果,搜索用时 15 毫秒
11.
Liposarcoma is a rare malignant tumor type and surgical resection is the gold standard treatment. The present study reported on the case of a 51-year-old woman who presented with a mass in the left upper abdomen. Computed tomography revealed a 32-cm giant retroperitoneal liposarcoma. Complete tumor resection was performed without the removal of other organs. Postoperative pathological examination indicated retroperitoneal well-differentiated liposarcoma and immunohistochemistry revealed S-100(−), MDM2(+), vimentin(+), CDK4(+), p16(+) and STAT6(+) results. The patient recovered well after the surgery. Complete tumor resection during the first surgery is key to cure liposarcoma. The present case report will be helpful for clinical oncologists to fully understand giant retroperitoneal liposarcoma and treat it accordingly.  相似文献   
12.
13.
BackgroundPancreatic cancer (PC) is among the most prevalent and deadliest endocrine tumors, yet the mechanisms governing its pathogenesis remain to be fully clarified. While ubiquitin-conjugating enzyme E2C (UBE2C) has been identified as an important oncogene in several cancers, its importance in PC has yet to be established.MethodsUBE2C expression in PC tumor samples and cell lines was examined via quantitative real-time polymerase chain reaction (qRT-PCR), while appropriate commercial kits were used to assess lactate production, ATP generation, and the uptake of glucose.ResultsUBE2C was found to be upregulated in PC patient tumors and correlated with poorer survival outcomes. In PC cell lines, the silencing of this gene suppressed the malignant activity of cells, thus supporting its identification as an oncogene in this cancer type. Mechanistically, UBE2C was found to promote enhanced matrix metalloproteinase (MMP) protein expression via activating the PI3K-Akt pathway. Moreover, it was found to bind to the epidermal growth factor receptor (EGFR), stabilizing it and driving additional PI3K-Akt pathway activation. UBE2C knockdown in PC cells impaired their uptake of glucose and their ability to produce lactate and ATP.ConclusionsIn conclusion, the results of this study support a role for UBE2C as a driver of metastatic PC progression owing to its ability to bind to EGFR and to induce signaling via the PI3K-Akt pathway.  相似文献   
14.
目的:比较关节镜辅助复位内固定(ARIF)和切开复位内固定(ORIF)治疗胫骨平台骨折的疗效。方法:回顾性分析2016年1月至2018年8月华中科技大学附属协和医院骨科收治的75例胫骨平台骨折患者的资料。男58例,女17例;年龄20~54岁,平均47岁。左侧42例,右侧33例。骨折根据Schatzker分型:Ⅰ型23例...  相似文献   
15.
16.
The management of congenital heart disease (CHD) remains a significant challenge in developing regions. Since 2006, China California Heart Watch has provided cardiac services in China’s Yunnan province. Our Grants for Kids program aims to diagnose and fund surgical and nonsurgical treatments for underprivileged children with congenitally malformed hearts. This report analyzes our patient outcomes. From 2007 to 2010, 36 children with CHD underwent either surgical or percutaneous procedures at local Chinese medical centers, and 94% of our patients could be contacted for follow-up assessment. The mortality and complication rates of our patient population compare favorably with international data. Our study provides a model through which networking with local hospitals and regional cardiac centers can be an effective way to assist developing areas in providing cardiac care to rural underserved populations.  相似文献   
17.
Dendritic cells (DCs) play a critical role in controlling T helper 2 (Th2) cell-dependent diseases, but the signaling mechanism that triggers this function is not fully understood. We showed that p38α activity in DCs was decreased upon HDM stimulation and dynamically regulated by both extrinsic signals and Th2-instructive cytokines. p38α-specific deletion in cDC1s but not in cDC2s or macrophages promoted Th2 responses under HDM stimulation. Further study showed that p38α in cDC1s regulated Th2-cell differentiation by modulating the MK2−c-FOS−IL-12 axis. Importantly, crosstalk between p38α-dependent DCs and Th2 cells occurred during the sensitization phase, not the effector phase, and was conserved between mice and humans. Our results identify p38α signaling as a central pathway in DCs that integrates allergic and parasitic instructive signals with Th2-instructive cytokines from the microenvironment to regulate Th2-cell differentiation and function, and this finding may offer a novel strategy for the treatment of allergic diseases and parasitic infection.  相似文献   
18.
Osteosarcoma is a kind of bone tumor with highly proliferative and invasive properties, a high incidence of pulmonary metastasis and a poor prognosis. Chemotherapy is the mainstay of treatment for osteosarcoma. Currently, there are no molecular targeted drugs approved for osteosarcoma treatment, particularly effective drugs for osteosarcoma with pulmonary metastases. It has been reported that fibroblast activation protein alpha (FAPα) is upregulated in osteosarcoma and critically associated with osteosarcoma progression and metastasis, demonstrating that FAPα-targeted agents might be a promising therapeutic strategy for osteosarcoma. In the present study, we reported that the FAPα-activated vinblastine prodrug Z-GP-DAVLBH exhibited potent antitumor activities against FAPα-positive osteosarcoma cells in vitro and in vivo. Z-GP-DAVLBH inhibited the growth and induced the apoptosis of osteosarcoma cells. Importantly, it also decreased the migration and invasion capacities and reversed epithelial–mesenchymal transition (EMT) of osteosarcoma cells in vitro and suppressed pulmonary metastasis of osteosarcoma xenografts in vivo. Mechanistically, Z-GP-DAVLBH suppressed the AXL/AKT/GSK-3β/β-catenin pathway, leading to inhibition of the growth and metastatic spread of osteosarcoma cells. These findings demonstrate that Z-GP-DAVLBH is a promising agent for the treatment of FAPα-positive osteosarcoma, particularly osteosarcoma with pulmonary metastases.KEY WORDS: Osteosarcoma, Fibroblast activation protein alpha, Growth, Pulmonary metastasis, Vinblastine prodrug, AXL, β-Catenin  相似文献   
19.
目的 :观察苯 +S9和单独用苯处理两种方法对体外培养的大鼠骨髓细胞的凋亡效应。方法 :Pereira KI法检测骨髓细胞中髓过氧化物酶的含量 ;荧光染色法检测细胞形态 ;DNA凝胶电泳法观察DNA裂解片段 ;流式细胞仪检测细胞凋亡率。结果 :DNA凝胶电泳 :苯 +S9组苯浓度为 7.5mmol·L-1,诱导时间 1h时即可见模糊的凋亡梯带 ;苯组当诱导浓度为 11.2 5mmol·L-1,诱导时间 3h时 ,电泳图谱呈现典型的DNA梯形条带。流式细胞仪检测各组的凋亡率也表明 ,两组诱导的凋亡呈剂量 效应和时间 效应关系 ,其中苯 +S9组各浓度分组及各时间分组与单独用苯组对应比较 ,凋亡率前者都比后者为高 ,与DNA凝胶电泳的结果相符合。结论 :在体外培养的大鼠骨髓细胞中 ,苯作为一种凋亡诱导剂在S9存在的情况下 ,以更低的剂量和时间点引起大鼠骨髓细胞的凋亡。  相似文献   
20.
目的 探讨硬膜外预置管用于经产妇分娩镇痛临床研究价值.方法 选择足月待产经产妇270例作为研究对象,依据患者需求和分娩镇痛方式将产妇分为3组,A组选择自愿要求分娩镇痛无禁忌证的足月经产妇90例,B组同期硬膜外无禁忌证的足月经产妇90例,另设同期未行分娩镇痛的足月经产妇90例作为C组,记录3组产妇产程时间,观察3组产妇缩宫素的使用率、分娩结局、新生儿窒息率以及产后出血率.结果 产程3组比较差异无统计学意义;会阴裂伤率A、B组比较差异无统计学意义,两组与C组比较差异有统计学意义(P<0.05);A、B组在缩宫素使用率和剖宫产率方面比较差异无统计学意义,两组与C组比较差异有统计学意义(P<0.05).3组产妇在新生儿窒息率、产后出血率等方面比较差异无统计学意义.结论 硬膜外预置管用于经产妇分娩镇痛安全性高,且满足产妇不同阶段镇痛需求,保证镇痛的及时性、有效性,具有重要的临床价值.  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