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   2423篇
  免费   126篇
  国内免费   21篇
耳鼻咽喉   53篇
儿科学   45篇
妇产科学   8篇
基础医学   290篇
口腔科学   57篇
临床医学   125篇
内科学   679篇
皮肤病学   88篇
神经病学   92篇
特种医学   106篇
外科学   583篇
综合类   5篇
预防医学   57篇
眼科学   23篇
药学   158篇
中国医学   1篇
肿瘤学   200篇
  2023年   15篇
  2022年   20篇
  2021年   71篇
  2020年   27篇
  2019年   41篇
  2018年   48篇
  2017年   47篇
  2016年   49篇
  2015年   68篇
  2014年   73篇
  2013年   77篇
  2012年   113篇
  2011年   136篇
  2010年   84篇
  2009年   83篇
  2008年   116篇
  2007年   115篇
  2006年   94篇
  2005年   118篇
  2004年   126篇
  2003年   106篇
  2002年   120篇
  2001年   73篇
  2000年   81篇
  1999年   86篇
  1998年   43篇
  1997年   35篇
  1996年   26篇
  1995年   17篇
  1994年   20篇
  1993年   15篇
  1992年   61篇
  1991年   48篇
  1990年   28篇
  1989年   13篇
  1988年   24篇
  1987年   11篇
  1986年   17篇
  1985年   17篇
  1984年   12篇
  1983年   17篇
  1979年   20篇
  1977年   10篇
  1975年   23篇
  1972年   12篇
  1971年   16篇
  1970年   8篇
  1967年   14篇
  1966年   13篇
  1965年   8篇
排序方式: 共有2570条查询结果,搜索用时 31 毫秒
1.
We describe a 53-year-old man with herpes simplex virus (HSV) brainstem encephalitis diagnosed based by positive HSV immunoglobulin M antibodies from cerebrospinal fluid. The MRI findings of this case had three unique features. First, the lesions were symmetrical. Second, the lesions may have been associated with reactivation of HSV infection in the region of the trigeminal nerve. Third, diffusion-weighted and apparent diffusion coefficient (ADC) imaging, conducted for the first time on an HSV brainstem encephalitis case, suggested that the lesions were associated with vasogenic edema.  相似文献   
2.
Humoral hypercalcemia of malignancy (HHM) in neoplastic syndrome has been most commonly reported in squamous cell carcinoma. Gallbladder carcinoma with HHM is uncommon. In this report, we describe a male case of gallbladder carcinoma with marked hypercalcemia and a high level of serum parathyroid hormone-related peptide (PTHrP). An immunohistochemical examination using PTHrP was also positive.  相似文献   
3.
4.
Abstract:  Angiotensin-converting enzyme inhibitor (ACEI) has become recognized as agents that have renoprotective effects in the treatment of progressive renal diseases including post-transplant kidneys. Previously we demonstrated the safety and effectiveness of ACEI treatment on the hypertensive proteinuric post-transplant patients ( N  = 10) who had been followed up for 12 months. However, not all patients show good response in urinary protein reduction. We aimed to analyse the histopathological factor(s) affecting the responsiveness of proteinuria to ACEI treatment. Fourteen post-transplant patients with proteinuria who were treated with ACEI and underwent allograft biopsy were analysed. Eight patients showed 50% or more reduction in proteinuria (responder). The other 6 patients showed less (< 50%) reduction in proteinuria (non-responder). There was no difference in clinical characteristics (BP, renal function, donor age, recipient body mass index), dietary sodium or protein intake, and diuretic use between the two groups. As a histopathological characteristic, glomerular size in responder group was significantly larger than that in non-responder group. This suggests that the large glomerular size at least partly contributes to the responsiveness in urinary protein reduction to ACEI treatment in kidney allograft recipients with proteinuria.  相似文献   
5.
A new surgical technique to treat retroperitoneal tumors with supradiaphragmatic vena caval invasion is described. In this technique, hepatic warm ischemia can be avoided with reversed hepatic outflow through the portal vein and neither hypothermic circulatory arrest nor cardiopulmonary bypass is necessary using centrifugal blood pump-driven bypass.  相似文献   
6.
We implanted normal peripheral blood lymphocytes (PBL) from healthy donors and splenic tissues from patients with gastric cancers into the severe combined immunodeficient (SCID) mouse, demonstrating that SCID mouse with splenic tissue can produce a high level of human immunoglobulin G (IgG). The normal PBLs at 10(7) and 10(8)/mouse were implanted intraperitoneally, and three splenic tissues with a size of 3 x 3 x 3 mm from gastric cancer patients were inoculated subcutaneously into the bilateral backs of the mice. At 2, 4, 6 and 8 weeks after inoculation, mice were killed, and the human IgG was assessed by an ELISA method. SCID mice with splenic tissue revealed high human IgG levels from 2 weeks after inoculation and approximately 2 mg of IgG per ml was observed at 8 weeks post-implantation, while the IgG levels in mice treated with PBLs were limited. Since the half life of the extrinsic human IgG was 10.2 days, the high level of human IgG in the SCID mice was supposed to be produced by human plasma cells in the splenic tissue from gastric cancer patients. This model was thought to be adequate for evaluating human immunological functions in vivo.  相似文献   
7.
A statistic analysis was carried out on the 4,956 inpatients admitted to our Department of Urology from April 1972 to December 1991. The patients included 3,399 males and 1,557 females. A total of 4,105 operations including 255 renal allotransplantations were performed on 3,590 patients. Open surgery for upper urinary tract stones has been replaced by extracorporeal shock-wave lithotripsy (ESWL) in the last three years.  相似文献   
8.
9.
Abstract Kidney cells are an important source of immunoregulatory molecules that regulate cell-to-cell interactions, which is the key step in the generation of the immunoresponse to alloantigens. In this study we identified the cytokines that are produced by both lymphoid cells and kidney cells when coincubated in mixed kidney lymphocyte cultures (MKLC). The capacity of kidney cells to stimulate the proliferation of effector allogeneic lymphocytes was assayed by incubating irradiated kidney cells and lymphocyte. The cytokine secretion profile in MKLC was investigated by incubating monolayers of kidney cells with effector peripheral blood mononuclear cells (PBMC). The culture supernatants were harvested on days 1, 2, 3, 4, 5, 6, 7, and 8 and assayed for IL-1β, IL-2, IL-6, and TNF alpha using an ELISA. Kidney cells, in comparison to PBMC stimulator cells were poor stimulators of the allo-proliferation even when HLA expression was increased by IFN gamma treatment. Compared to lymphocyte or kidney cells incubated alone, MKLC induced a considerable stimulation of cytokine production. This increase in cytokine production was observed essentially for IL-2 and IL-6 (at day 3, a 10-fold increase in IL-2 and a 5-fold increase in IL-6). This study provided evidence that target kidney cells and effector lymphocyte interactions generate a number of cytokines such as IL-11, IL-2, IL-6, or TNF alpha. These cytokines are known to modulate alloproliferation and generation of cytotoxic J lymphocytes (CTL).  相似文献   
10.
We assessed the relations of visual hallucinations (VH) to cardiovascular autonomic dysfunction in patients with Parkinson's disease (PD). The subjects were 37 patients without VH (VH(-)) and 31 with VH (VH(+)). Autonomic function was evaluated on the basis of cardiac 123-radioiodinated metaiodobenzylguanidine (123I-MIBG) uptake and hemodynamic testing with Valsalva maneuver. Systolic blood pressure (SBP) and plasma norepinephrine concentrations (NE) were measured by tilt-table testing. 123I-MIBG uptake was lower in VH(+) than VH(-). Hemodynamic studies showed that VH(-) had only cardiac sympathetic and parasympathetic dysfunction, while VH(+) additionally had reduced vasomotor sympathetic functions. The fall in SBP during tilt-table testing was greater in VH(+) than VH(-). NE and its difference in the supine and upright positions were decreased in VH(+). We conclude that cardiac and vasomotor sympathetic dysfunction is more severe in VH(+) than in VH(-). Severe dysfunction in PD with VH is probably attributed to Lewy-body lesions or neuronal loss in sympathetic ganglia, the central autonomic system, or both.  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