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   1464篇
  免费   98篇
  国内免费   1篇
耳鼻咽喉   12篇
儿科学   75篇
妇产科学   96篇
基础医学   246篇
口腔科学   24篇
临床医学   135篇
内科学   271篇
皮肤病学   23篇
神经病学   83篇
特种医学   25篇
外科学   183篇
综合类   19篇
预防医学   90篇
眼科学   32篇
药学   79篇
中国医学   9篇
肿瘤学   161篇
  2024年   1篇
  2023年   16篇
  2022年   27篇
  2021年   60篇
  2020年   34篇
  2019年   56篇
  2018年   53篇
  2017年   41篇
  2016年   42篇
  2015年   49篇
  2014年   73篇
  2013年   95篇
  2012年   136篇
  2011年   149篇
  2010年   77篇
  2009年   60篇
  2008年   120篇
  2007年   90篇
  2006年   70篇
  2005年   75篇
  2004年   68篇
  2003年   66篇
  2002年   42篇
  2001年   13篇
  2000年   6篇
  1999年   9篇
  1998年   4篇
  1997年   4篇
  1996年   8篇
  1995年   1篇
  1994年   5篇
  1993年   2篇
  1990年   1篇
  1989年   1篇
  1988年   1篇
  1987年   2篇
  1984年   2篇
  1983年   1篇
  1981年   1篇
  1979年   1篇
  1960年   1篇
排序方式: 共有1563条查询结果,搜索用时 15 毫秒
1.
The coronavirus disease 2019 (COVID-19) pandemic has rapidly created widespread impacts on global health and the economy. Data suggest that women are less susceptible to severe illness. However, sex-disaggregated data are incomplete, leaving room for misinterpretation, and focusing only on biologic sex underestimates the gendered impact of the pandemic on women. This narrative review summarizes what is known about gender disparities during the COVID-19 pandemic and the economic, domestic, and health burdens along with overlapping vulnerabilities related to the pandemic. In addition, this review outlines recommended strategies that advocacy groups, community leaders, and policymakers should implement to mitigate the widening gender disparities related to COVID-19.  相似文献   
2.
OBJECTIVE: To analyse morbidity after completion total thyroidectomy compared with primary total thyroidectomy in a specialist thyroid surgery centre. DESIGN: Retrospective study. SETTING: Tertiary referral hospital, India. PATIENTS: Medical records of 143 patients who had total thyroidectomy between January 1990 and December 1999. 95 had primary thyroidectomies and 48 were completion thyroidectomies. MAIN OUTCOME MEASURES: Complication rate in both groups. RESULTS: The groups were comparable in respect of clinicopathological variables. Residual tumour was found in 19/48 (40%). After completion thyroidectomy, transient hypoparathyroidism and transient recurrent laryngeal nerve palsy were recorded in 8/48 (17%) and 2/48 (4%), respectively. No permanent hypoparathyroidism or permanent recurrent laryngeal nerve palsy was recorded in the completion thyroidectomy group. CONCLUSIONS: Completion thyroidectomy can be done with acceptable morbidity in a specialist thyroid surgery centre. Fear of increased morbidity after the procedure should not deter surgeon from doing this operation or referring the patients to a specialist centre.  相似文献   
3.
Physicians who treat multiple sclerosis (MS) face the challenge of patients exhibiting ongoing disease activity, including exacerbations, loss of functional capabilities, intellectual decline, and radiologic progression, despite being on a disease-modifying agent (DMA). After searching for factors that might at least in part explain these changes—such as nonadherent drug-taking behavior, or the presence of interfer-on-neutralizing antibodies—some providers may ultimately decide to switch the patient to another DMA. In most circumstances, patients likely derive only partial effects from these agents, even in the absence of compromising factors. Thus, a number of factors must be considered in order to intensify the treatment regimen in response to disease progression. In the context of an inadequate treatment response to a DMA, some clinicians will convert the patient to an alternative therapy, and others will instead use a second agent in combination with the first (the so-called platform agent). In the first of this two-part series, we explored the use of anti-inflammatory CS and ACTH to treat MS exacerbations. Although we underscored the limited availability of evidence-based studies to support specific regimens for this purpose, there is an even greater paucity of data to support the routine use of these agents in order to achieve chronic disease-modifying effects in those who continue to deteriorate clinically, radiographically, or both. Without doubt, a number of factors influence the formulation of combination treatment plan for MS. Nevertheless, we will focus on the rationale and practical schemes that can be considered for using corticosteroids (CS) (and perhaps even ACTH) in an attempt to modify various domains of ongoing disease activity.  相似文献   
4.
Earlier we reported that vaccination of leprosy patients withMycobacterium w induces an immune response directed predominantly against low molecular weight antigens. One of these antigens, with a molecular mass of 30-kDa, was recognized by a majority of the vaccinated subjects as well as the tuberculoid leprosy patients and healthy contacts. In the present communication we report further characterization of this antigen. Immunofluorescence and Western blot studies with antibodies raised against this antigen demonstrate that it is associated with the cell surface and has homologues present inM. leprae andM. tuberculosis. Delayed-type hypersensitivity studies carried out in guinea pigs immunized with the 30-kDa antigen show that in addition to sharing B cell determinants, this immunodominant antigen ofM. w also shares T cell determinants withM. leprae andM. tuberculosis.  相似文献   
5.
Monocyte chemoattractant protein-1 (MCP-1) is a pivotal mediator of angiocentric granuloma formation in glucan-induced pulmonary granulomatous vasculitis. Based on the rationale that mononuclear phagocytes retrieved from granulomas are rich sources of nitric oxide (NO) and that the recruitment of mononuclear phagocytes into lesions abates as granuloma formation slows, we tested the hypothesis that MCP-1 gene expression is regulated by a NO-sensitive mechanism. Preexposure of endothelial cell (EC) monolayers to NO donor compounds markedly reduced cytokine-induced MCP-1 expression and cytosolic-to-nuclear translocation of nuclear factor-kappa B (NF-B), reversed fluctuations in endothelial reduced glutathione (GSH) pools but did not affect cGMP concentrations. The lungs of mice bearing targeted disruptions of the inducible nitric oxide synthase (iNOS) gene exhibited significantly higher concentrations of MCP-1 following glucan infusion than did those of wild-type mice. Cumulatively, these data suggest that NO suppresses MCP-1 expression by blunting the redox changes associated with cytokine-induced EC activation.  相似文献   
6.
7.
8.
Adenoid cystic carcinoma of the breast diagnosed by fine-needle aspiration   总被引:2,自引:0,他引:2  
Fine-needle aspiration cytology remains a useful tool for preoperative diagnosis of breast lesions. We describe a case of adenoid cystic carcinoma (ACC) of the breast detected by ultrasound-guided fine-needle aspiration (FNA). Subsequent histopathology corroborated the diagnosis. ACC is a rare but distinctive neoplasm of the breast that can be accurately diagnosed by FNA. Its infrequent presentation, favorable prognosis, and relatively conservative management in the breast prompt us to reinforce its features.  相似文献   
9.
Evenomation by arachnids of the genus Loxosceles frequently results in disfiguring necrotic skin lesions. The cellular and molecular mechanisms which contribute to lesion development are incompletely defined but appear to involve participation of several pro-inflammatory mediators. We have recently observed that Loxosceles deserta venom induces the production of chemokines in human umbilical vein endothelial cells (HUVECs) and human pulmonary epithelial cells. In the present study we observed that Loxosceles deserta venom induces the expression of vascular endothelial growth factor (VEGF) in human keratinocytes but little in smooth muscle cells and none in pulmonary epithelial cells. A potent endothelial cell-specific mitogen, VEGF induces angiogenesis and vascular permeability in vivo. RNase protection assay data indicate that VEGF mRNA concentrations in keratinocytes are significantly increased at 2 h following venom exposure. These data suggest that keratinocyte-derived VEGF may contribute to the vasodilation, edema and erythema which occur following Loxosceles evenomation.  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