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   2252篇
  免费   88篇
  国内免费   6篇
耳鼻咽喉   6篇
儿科学   99篇
妇产科学   42篇
基础医学   428篇
口腔科学   39篇
临床医学   192篇
内科学   356篇
皮肤病学   109篇
神经病学   238篇
特种医学   62篇
外科学   176篇
综合类   6篇
预防医学   172篇
眼科学   40篇
药学   218篇
中国医学   7篇
肿瘤学   156篇
  2023年   18篇
  2022年   32篇
  2021年   58篇
  2020年   24篇
  2019年   57篇
  2018年   40篇
  2017年   32篇
  2016年   52篇
  2015年   53篇
  2014年   78篇
  2013年   102篇
  2012年   163篇
  2011年   150篇
  2010年   92篇
  2009年   57篇
  2008年   145篇
  2007年   144篇
  2006年   163篇
  2005年   119篇
  2004年   115篇
  2003年   106篇
  2002年   108篇
  2001年   24篇
  2000年   15篇
  1999年   27篇
  1998年   30篇
  1997年   29篇
  1996年   18篇
  1995年   19篇
  1994年   15篇
  1993年   15篇
  1992年   9篇
  1991年   7篇
  1990年   14篇
  1988年   13篇
  1987年   12篇
  1986年   9篇
  1985年   8篇
  1984年   14篇
  1982年   13篇
  1981年   10篇
  1980年   9篇
  1978年   9篇
  1977年   5篇
  1976年   9篇
  1974年   7篇
  1971年   5篇
  1967年   9篇
  1959年   5篇
  1958年   6篇
排序方式: 共有2346条查询结果,搜索用时 31 毫秒
31.
The impact of chronological age on longitudinal body growth from early childhood through adolescence using detailed anthropometric methods has not yet been studied in children with chronic kidney disease (CKD). We have evaluated growth failure by measuring four components of linear growth: body height (HT), sitting height (SHT), arm length (AL) and leg length (LL). Data were prospectively collected for up to 7 years on 190 boys (3–21 years old) with congenital or hereditary CKD (all had developed at least stage 2 CKD by the age of 10 years). Patients showed the most severe growth failure in early childhood, followed by an acceleration in growth in pre-puberty, a slowing-down of growth at puberty, as expected, and thereafter a late speeding-up of growth until early adulthood. This pattern was observed irrespective of the degree of CKD and different treatment modalities, such as conservative treatment, recombinant human growth hormone (rhGH) therapy or transplantation. LL showed the most dynamic growth changes of all the parameters evaluated and emerged as the best indicator of statural growth in children with CKD. A specific age-dependent pattern of physical growth was identified in pediatric male CKD patients. This growth pattern should be considered in the evaluation of individual growth and the assessment of treatment efficacy such as rhGH therapy.  相似文献   
32.
Basic fibroblast growth factor (bFGF) is a potent angiogenic factor produced by cells of mesodermal and neuroectodermal origin. Despite numerous advances, the precise mechanism of bFGF release from cells still remains unknown. Upon release from cells, the protein is stored and protected in the extracellular matrix by binding to heparan sulfate proteoglycans. A number of reports suggest that degrading enzymes secreted by mast cells may play a role in the release of bFGF from connective tissue stores. Additionally, mast cells are believed to play a role in the formation of new blood vessels. In this report, we studied the events involved in neovascularization using a well-characterized model of angiogenesis in rabbits where neovascularization is induced by transfer of a well-perfused rectus abdominis muscle flap to an ischemic limb. Using this model, we demonstrate that bFGF expression is induced in normal myofibers and bFGF is released in the wound fluid at the ischemic/nonischemic interface. The highest concentrations of bFGF were detected on days 14 and 21 postoperation. We also show that the number of mast cells and their degranulation correlate with the release of bFGF from adjacent muscle tissue and the appearance of the growth factor in the wound fluid. There appears to exist a temporal correlation between number of mast cells, their degranulation, and the release of bFGF during angiogenesis in vivo.  相似文献   
33.
BACKGROUND: Antigen-specific immunoadsorption combined with rituximab offers the possibility for ABO-incompatible kidney transplantation without splenectomy. PATIENT AND METHOD: An 8-year-old mentally retarded girl with steroid-resistant nephrotic syndrome and focal segmental glomerulosclerosis due to mitochondriopathy poorly tolerated hemodialysis. Paternal blood group A1B was incompatible with blood group B of the child. Therefore, we decided to perform the first ABO-incompatible renal transplantation in a child in Germany using antigen-specific immunoadsorption. Rituximab (1 x 375 mg/m2) was administered 2 weeks before the first immunoadsorption (Glycosorb) ABO A-column). Triple-drug immunosuppression (tacrolimus, mycophenolate mofetil and prednisolone) was simultaneously started with immunoadsorption. Initial tacrolimus levels were targeted between 15 and 20 ng/ml. Before transplantation, six immunoadsorptions were applied on days -9, -7, -4, -3, -2 and -1. Intravenous immunoglobulin (0.5 g/kg) was administered preoperatively. After transplantation, three immunoadsorptions were performed on days +4, +6 and +8. RESULTS: Before transplantation, antibody (Ab) titers against paternal erythrocytes (20 degrees C) were reduced from 1 : 64 to 1 : 4 by six antigen-specific immunoadsorptions. After transplantation, we performed three more immunoadsorptions and the Ab titers were stable between 1 : 1 and 1 : 8. One, 2 and 8 months later we observed increases in the Ab titer up to 1 : 32 requiring no change in immunosuppressive therapy. No side effects of immunoadsorption were observed. The girl had excellent initial graft function with a serum creatinine of 55 to 70 micromol/l. Two weeks after transplantation, graft biopsy showed no signs of rejection; there was focal positivity for C4d only. Twelve months after transplantation, renal function was stable, with a serum creatinine of 117 micromol/l. Episodes of rejection or severe infections were absent. CONCLUSION: ABO-incompatible transplantation using antigen-specific immunoadsorption and rituximab may serve as a suitable alternative for children urgently needing renal transplantation and missing a blood group-compatible donor.  相似文献   
34.
Pagetoid reticulosis (Woringer‐Kolopp disease) is a rare subtype of cutaneous CD8‐positive T‐cell lymphoma. A 41‐year‐old man presented with a 7‐year history with a slowly progressive erythematous plaque on his right buttocks. With the working diagnosis of psoriasis, he was treated with topical corticosteroids which produced no improvement. Histological examination showed an epidermotropic T‐cell lymphoma with predominance of CD8‐ vs.CD4‐positive lymphocytes. Based on the clinical picture and the histological findings, we diagnosed pagetoid reticulosis. Excision of the plaque and cream PUVA photo‐chemotherapy produced long‐term remission.  相似文献   
35.
36.
We report two patients with normocomplementaemic urticarial vasculitis with impressive response to omalizumab. This contrasts recent reports on hypocomplementaemic urticarial vasculitis syndrome, highlighting the need for clinical trials of omalizumab in normocomplementaemic urticarial vasculitis.  相似文献   
37.
The interactions between neurons, immune and immune-like glial cells can initiate the abnormal processes that underlie neuropathic pain. In the peripheral nervous system the resident macrophages may play an important role. In this study we investigated in experimental adult Sprague-Dawley rats how Iba-1 (ionized calcium binding adaptor molecule 1) (+) resident macrophages in the dorsal root ganglion (DRG) are activated after a spinal nerve ligation (SNL) or streptozotocin (STZ)-induced diabetes. The activation profile was defined by comparing the responses of resident macrophages against microglia in the spinal cord as they share a common origin. After SNL, the Iba-1 (+) macrophages in L5 DRG reached their activation peak 5 days later, clustered as satellite cells around large A-neurons, expressed the MHC-II marker, but did not show p-p38 and p-ERK1/2 activation and did not secrete IL-18. After STZ-induced diabetes, the Iba-1 (+) macrophages reached their activation peak 1 week later in L4 and L5 DRG, remained scattered between neurons, expressed the MHC-II marker only in L5 DRG, did not show p-p38 and p-ERK1/2 activation and did not secrete any of the investigated cytokines/chemokines. These responses suggest that depending on the type of lesion DRG Iba-1 (+) resident macrophages have different activation mechanisms, which are dissimilar to those in microglia.  相似文献   
38.
39.
The present study investigates stability of adult attachment style and concurrent covariation between attachment security and coping and well-being within a 6-year longitudinal-sequential study, with a sample ranging from late adolescence to late adulthood. The findings indicate that attachment style was relatively stable over the six-year period; nevertheless, it was characterized more by fluidity than by stability. Fluctuation in attachment security showed a negative concurrent covariation with defensive coping and depressive symptoms, but a positive covariation with integrative coping and self-perceived well-being. At any point when participants were better copers and reported a better state of well-being (than their own average baseline), they were also more secure (than their own average baseline). An age effect in attachment change was also found. Over time, older individuals became more secure and more dismissing, but less preoccupied than young people.  相似文献   
40.
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