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   1433443篇
  免费   96042篇
  国内免费   2372篇
耳鼻咽喉   20476篇
儿科学   48057篇
妇产科学   42588篇
基础医学   207436篇
口腔科学   40047篇
临床医学   120207篇
内科学   278898篇
皮肤病学   30202篇
神经病学   108878篇
特种医学   58961篇
外国民族医学   459篇
外科学   221014篇
综合类   27449篇
现状与发展   1篇
一般理论   301篇
预防医学   105898篇
眼科学   32609篇
药学   108712篇
  3篇
中国医学   2599篇
肿瘤学   77062篇
  2018年   15028篇
  2017年   12478篇
  2016年   12921篇
  2015年   15848篇
  2014年   19666篇
  2013年   27210篇
  2012年   41986篇
  2011年   39866篇
  2010年   23020篇
  2009年   23300篇
  2008年   36616篇
  2007年   40167篇
  2006年   40904篇
  2005年   47717篇
  2004年   47766篇
  2003年   42640篇
  2002年   37665篇
  2001年   61249篇
  2000年   60804篇
  1999年   54860篇
  1998年   14637篇
  1997年   13004篇
  1996年   13336篇
  1995年   12623篇
  1994年   12008篇
  1992年   46112篇
  1991年   45673篇
  1990年   45378篇
  1989年   43950篇
  1988年   40938篇
  1987年   40051篇
  1986年   38155篇
  1985年   36145篇
  1984年   26654篇
  1983年   23004篇
  1982年   13141篇
  1981年   11516篇
  1979年   25593篇
  1978年   17710篇
  1977年   15098篇
  1976年   14170篇
  1975年   16085篇
  1974年   19096篇
  1973年   18235篇
  1972年   17475篇
  1971年   16347篇
  1970年   15251篇
  1969年   14711篇
  1968年   13756篇
  1967年   12220篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
Neutrophils can form neutrophil extracellular traps (NETs) to capture microbes and facilitate their clearance. NETs consist of decondensed chromatin decorated with anti-microbial proteins. Here, we describe the effect of neutrophil proteases on the protein content of NETs. We show that the neutrophil serine proteases degrade several neutrophil proteins associated with NETs. Interestingly, the anti-bacterial proteins associated with NETs, such as myeloperoxidase, calgranulin B and neutrophil elastase (NE), seem to be less susceptible to proteolytic degradation than other NET proteins, such as actin and MNDA. NETs have been proposed to play a role in autoimmune reactions. Our data demonstrate that a large number of the autoepitopes of NET proteins that are recognized by autoantibodies produced by systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) patients are also removed by the proteases. In conclusion, neutrophil serine proteases have a major impact on the NET proteome and the proteolytic changes of NET-associated proteins may counteract autoimmune reactions to NET components.  相似文献   
73.
Ovarian cancer is the fourth most common cause of cancer-related death in women in the developed world, and one of the most heritable cancers. One of the most significant risk factors for epithelial ovarian cancer (EOC) is a family history of breast and/or ovarian cancer. Combined risk factors can be used in models to stratify risk of EOC, and aid in decisions regarding risk-reduction strategies. Germline pathogenic variants in EOC susceptibility genes including those involved in homologous recombination and mismatch repair pathways are present in approximately 22% to 25% of EOC. These genes are associated with an estimated lifetime risk of EOC of 13% to 60% for BRCA1 variants and 10% to 25% for BRCA2 variants, with lower risks associated with remaining genes. Genome-wide association studies have identified single nucleotide polymorphisms (SNPs) thought to explain an additional 6.4% of the familial risk of ovarian cancer, with 34 susceptibility loci identified to date. However, an unknown proportion of the genetic component of EOC risk remains unexplained. This review comprises an overview of individual genes and SNPs suspected to contribute to risk of EOC, and discusses use of a polygenic risk score to predict individual cancer risk more accurately.  相似文献   
74.
IntroductionPain is highly prevalent in patients with multiple sclerosis (MS); it is chronic in 50% of cases and is classified as nociceptive, neuropathic, or mixed-type. Pain affects quality of life, sleep, and the activities of daily living. Electrotherapy is an interesting alternative or complementary treatment in the management of pain in MS, with new innovations constantly appearing.Material and methodsThis study evaluates the effectiveness of treatment with monopolar dielectric transmission of pulsed electromagnetic fields (PEMF) for pain associated with MS. We performed a randomised, placebo-controlled clinical trial including 24 patients, who were assessed with the Brief Pain Inventory, the Multiple Sclerosis International Quality of Life questionnaire, the Beck Depression Inventory, and the Modified Fatigue Impact Scale.ResultsStatistically significant improvements were observed in maximum and mean pain scores, as well as in the impact of pain on work, personal relationships, and sleep and rest. Not significant differences were found between the treatment and placebo groups.ConclusionsTreatment with PEMF may be effective in reducing pain in patients with MS, although further research is necessary to confirm its effectiveness over placebo and to differentiate which type of pain may be more susceptible to this treatment.  相似文献   
75.
76.
77.
In this review we summarize the impact of the various modalities of breast cancer therapy coupled with intrinsic patient factors on incidence of subsequent treatment-induced myelodysplasia and acute myelogenous leukemia (t-MDS/AML). It is clear that risk is increased for patients treated with radiation and chemotherapy at younger ages. Radiation is associated with modest risk, whereas chemotherapy, particularly the combination of an alkylating agent and an anthracycline, carries higher risk and radiation and chemotherapy combined increase the risk markedly. Recently, treatment with granulocyte colony-stimulating factor (G-CSF), but not pegylated G-CSF, has been identified as a factor associated with increased t-MDS/AML risk. Two newly identified associations may link homologous DNA repair gene deficiency and poly (ADP-ribose) polymerase inhibitor treatment to increased t-MDS/AML risk. When predisposing factors, such as young age, are combined with an increasing number of potentially leukemogenic treatments that may not confer large risk singly, the risk of t-MDS/AML appears to increase. Patient and treatment factors combine to form a biological cascade that can trigger a myelodysplastic event. Patients with breast cancer are often exposed to many of these risk factors in the course of their treatment, and triple-negative patients, who are often younger and/or BRCA positive, are often exposed to all of them. It is important going forward to identify effective therapies without these adverse associated effects and choose existing therapies that minimize the risk of t-MDS/AML without sacrificing therapeutic gain.

Implications for Practice

Breast cancer is far more curable than in the past but requires multimodality treatment. Great care must be taken to use the least leukemogenic treatment programs that do not sacrifice efficacy. Elimination of radiation and anthracycline/alkylating agent regimens will be helpful where possible, particularly in younger patients and possibly those with homologous repair deficiency (HRD). Use of colony-stimulating factors should be limited to those who truly require them for safe chemotherapy administration. Further study of a possible leukemogenic association with HRD and the various forms of colony-stimulating factors is badly needed.
  相似文献   
78.
79.
80.
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