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   4355024篇
  免费   360597篇
  国内免费   14205篇
耳鼻咽喉   60719篇
儿科学   141072篇
妇产科学   117218篇
基础医学   666840篇
口腔科学   123554篇
临床医学   396602篇
内科学   782665篇
皮肤病学   107931篇
神经病学   367173篇
特种医学   173098篇
外国民族医学   733篇
外科学   661631篇
综合类   129066篇
现状与发展   24篇
一般理论   2694篇
预防医学   365543篇
眼科学   102140篇
药学   308840篇
  21篇
中国医学   11273篇
肿瘤学   210989篇
  2021年   54574篇
  2019年   58402篇
  2018年   73461篇
  2017年   55811篇
  2016年   61752篇
  2015年   75060篇
  2014年   109410篇
  2013年   174735篇
  2012年   118883篇
  2011年   123509篇
  2010年   124211篇
  2009年   126356篇
  2008年   110476篇
  2007年   117223篇
  2006年   126026篇
  2005年   121218篇
  2004年   122968篇
  2003年   112810篇
  2002年   102383篇
  2001年   154573篇
  2000年   150153篇
  1999年   139844篇
  1998年   70666篇
  1997年   67158篇
  1996年   65459篇
  1995年   60865篇
  1994年   54629篇
  1993年   50865篇
  1992年   104835篇
  1991年   101443篇
  1990年   97488篇
  1989年   95254篇
  1988年   88447篇
  1987年   86909篇
  1986年   83017篇
  1985年   81562篇
  1984年   68245篇
  1983年   61136篇
  1982年   48524篇
  1981年   45171篇
  1980年   42526篇
  1979年   61059篇
  1978年   49061篇
  1977年   43056篇
  1976年   40147篇
  1975年   40061篇
  1974年   45051篇
  1973年   43673篇
  1972年   40949篇
  1971年   38107篇
排序方式: 共有10000条查询结果,搜索用时 484 毫秒
991.
992.
In December 2019, a new type of coronavirus was detected for the first time in Wuhan, Hubei Province, China. According to the reported data, the emerging coronavirus has spread worldwide, infecting more than fifty-seven million individuals, leading to more than one million deaths. The current study aimed to review and discuss the hematological findings of COVID-19. Laboratory changes and hematologic abnormalities have been reported repeatedly in COVID-19 patients. WBC count and peripheral blood lymphocytes are normal or slightly reduced while these indicators may change with the progression of the disease. In addition, several studies demonstrated that decreased hemoglobin levels in COVID-19 patients were associated with the severity of the disease. Moreover, thrombocytopenia, which is reported in 5%-40% of patients, is known to be associated with poor prognosis of the disease. COVID-19 can present with various hematologic manifestations. In this regard, accurate evaluation of laboratory indicators at the beginning and during COVID-19 can help physicians to adjust appropriate treatment and provide special and prompt care for those in need.  相似文献   
993.
994.
995.
996.
997.
The special interest group on sensitive skin of the International Forum for the Study of Itch previously defined sensitive skin as a syndrome defined by the occurrence of unpleasant sensations (stinging, burning, pain, pruritus and tingling sensations) in response to stimuli that normally should not provoke such sensations. This additional paper focuses on the pathophysiology and the management of sensitive skin. Sensitive skin is not an immunological disorder but is related to alterations of the skin nervous system. Skin barrier abnormalities are frequently associated, but there is no cause and direct relationship. Further studies are needed to better understand the pathophysiology of sensitive skin – as well as the inducing factors. Avoidance of possible triggering factors and the use of well-tolerated cosmetics, especially those containing inhibitors of unpleasant sensations, might be suggested for patients with sensitive skin. The role of psychosocial factors, such as stress or negative expectations, might be relevant for subgroups of patients. To date, there is no clinical trial supporting the use of topical or systemic drugs in sensitive skin. The published data are not sufficient to reach a consensus on sensitive skin management. In general, patients with sensitive skin require a personalized approach, taking into account various biomedical, neural and psychosocial factors affecting sensitive skin.  相似文献   
998.
999.
Osteogenesis imperfecta (OI) is a collagen-related bone disorder characterized by fragile osteopenic bone and muscle weakness. We have previously shown that the soluble activin receptor type IIB decoy (sActRIIB) molecule increases muscle mass and improves bone strength in the mild to moderate G610C mouse model of OI. The sActRIIB molecule binds multiple transforming growth factor-β (TGF-β) ligands, including myostatin and activin A. Here, we investigate the musculoskeletal effects of inhibiting activin A alone, myostatin alone, or both myostatin and activin A in wild-type (Wt) and heterozygous G610C (+/G610C) mice using specific monoclonal antibodies. Male and female Wt and +/G610C mice were treated twice weekly with intraperitoneal injections of monoclonal control antibody (Ctrl-Ab, Regn1945), anti-activin A antibody (ActA-Ab, Regn2476), anti-myostatin antibody (Mstn-Ab, Regn647), or both ActA-Ab and Mstn-Ab (Combo, Regn2476, and Regn647) from 5 to 16 weeks of age. Prior to euthanasia, whole body composition, metabolism and muscle force generation assessments were performed. Post euthanasia, hindlimb muscles were evaluated for mass, and femurs were evaluated for changes in microarchitecture and biomechanical strength using micro–computed tomography (μCT) and three-point bend analyses. ActA-Ab treatment minimally impacted the +/G610C musculoskeleton, and was detrimental to bone strength in male +/G610C mice. Mstn-Ab treatment, as previously reported, resulted in substantial increases in hindlimb muscle weights and overall body weights in Wt and male +/G610C mice, but had minimal skeletal impact in +/G610C mice. Conversely, the Combo treatment outperformed ActA-Ab alone or Mstn-Ab alone, consistently increasing hindlimb muscle and body weights regardless of sex or genotype and improving bone microarchitecture and strength in both male and female +/G610C and Wt mice. Combinatorial inhibition of activin A and myostatin more potently increased muscle mass and bone microarchitecture and strength than either antibody alone, recapturing most of the observed benefits of sActRIIB treatment in +/G610C mice. © 2022 American Society for Bone and Mineral Research (ASBMR).  相似文献   
1000.
SCN1A is one of the most relevant epilepsy genes. In general, de novo severe mutations, such as truncating mutations, lead to a classic form of Dravet syndrome (DS), while missense mutations are associated with both DS and milder phenotypes within the GEFS+ spectrum, however, these phenotype‐genotype correlations are not entirely consistent. Case report. We report an 18‐year‐old woman with a history of recurrent febrile generalized tonic‐clonic seizures (GTCS) starting at age four months and afebrile asymmetric GTCS and episodes of arrest, suggestive of focal impaired awareness seizures, starting at nine months. Her psychomotor development was normal. Sequencing of SCN1A revealed a heterozygous de novo truncating mutation (c.5734C>T, p.Arg1912X) in exon 26. Conclusion. Truncating mutations in SCN1A may be associated with milder phenotypes within the GEFS+ spectrum. Accordingly, SCN1A gene testing should be performed as part of the assessment for sporadic patients with mild phenotypes that fit within the GEFS+ spectrum, since the finding of a mutation has diagnostic, therapeutic and genetic counselling implications.  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