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   589篇
  免费   30篇
  国内免费   3篇
耳鼻咽喉   8篇
儿科学   1篇
基础医学   77篇
口腔科学   1篇
临床医学   33篇
内科学   184篇
皮肤病学   6篇
神经病学   9篇
特种医学   8篇
外科学   77篇
综合类   1篇
预防医学   1篇
眼科学   131篇
药学   7篇
肿瘤学   78篇
  2023年   3篇
  2022年   7篇
  2021年   15篇
  2020年   12篇
  2019年   10篇
  2018年   22篇
  2017年   4篇
  2016年   11篇
  2015年   16篇
  2014年   16篇
  2013年   22篇
  2012年   47篇
  2011年   39篇
  2010年   27篇
  2009年   21篇
  2008年   31篇
  2007年   31篇
  2006年   28篇
  2005年   23篇
  2004年   24篇
  2003年   25篇
  2002年   32篇
  2001年   7篇
  2000年   16篇
  1999年   7篇
  1998年   6篇
  1997年   5篇
  1996年   8篇
  1995年   14篇
  1994年   8篇
  1993年   11篇
  1992年   6篇
  1991年   4篇
  1990年   13篇
  1989年   9篇
  1988年   10篇
  1987年   6篇
  1986年   10篇
  1984年   2篇
  1983年   6篇
  1980年   1篇
  1979年   1篇
  1978年   1篇
  1971年   1篇
  1969年   2篇
  1967年   1篇
  1965年   1篇
排序方式: 共有622条查询结果,搜索用时 31 毫秒
1.
A case of pancreatic tumor with features of both duct and islet cell components was found incidentally at autopsy in a 76 year old male who had died of intrahepatic cholan-giocarcinoma. The tumor, measuring about l.0cm in diameter, was located in the pancreatic tail. The tumor was composed of two distinct cell populations, islet cells and duct cells. Immunocytochemically, nearly all of the former cells were positive for insulin but negative for cytokeratin, carcinoembryonic antigen (CEA) and mucin, while the latter were positive for cytokeratin, CEA and mucin but negative for insulin. Additionally, a majority of the tumor cells that had formed islet-like structures were positive for neuron specific enolase (NSE), whereas NSE-positive cells were found only rarely in duct components. Electron microscopy confirmed the presence of two cell populations. Simultaneous occurrence of duct and islet cell components in a single pancreatic tumor indicates an intimate histogenetic relationship between pancreatic endocrine and duct cells. Acta Pathol Jpn 39: 328 335, 1989.  相似文献   
2.
A case of a rare renal tumor showing characteristic histo-logic features is presented. The patient was a 54 year old female, whose renal tumor was incidentally detected on abdominal ultrasound (US) examination. Ultrasound, computed tomography and angiography findings were consistent with a diagnosis of renal cell carcinoma of the hypovascular type. Left nephrectomy was performed. The tumor, which measured 2.6 times2.6 times 2.5 cm, was located in the left renal cortex, and had a uniformly whitish-yellow cut surface and well-defined margin. Histologically, the tumor was characterlzed by its monomorphous growth pattern and was composed of uniformly small cells arranged in a tubular or rosette-like pattern. The tumor cells had scant cytoplasm and the nuclei were small, round and regular. These histo-logic features resembled the epithelial elements of a metanephric hamartoma in the nephroblastomatosis complex in infants. However, there was no mitosis and cellular atypia was minimal, suggesting benignity. According to these his-tologic features, the diagnosis of metanephric adenoma was made. Its clinicopathologic features are discussed.  相似文献   
3.
AIMS: To investigate the relation between localised amyloidosis and immunocytic dyscrasia. METHODS: Open lung biopsy specimens from a 72 year old man with multiple nodules in the right middle and lower lung were stained with haematoxylin-eosin, Congo red, and antibodies against IgG, IgA, IgM, and kappa and lambda light chains. Semi-nested PCR amplification for the immunoglobulin heavy chain (IgH) gene was performed using consensus primers for the VDJ region of the IgH gene, FR3A, LJH, and VLJH. RESULTS: The biopsy specimens contained eosinophilic amorphous material stained with Congro red and anti-kappa light chain, and surrounded by inflammatory cells intermingled with plasma cells. Plasma cells in the adjacent amorphous material showed cytoplasmic staining with anti-kappa. Polymerase chain reaction revealed a discrete amplified band of apparently uniform size with background smear. CONCLUSIONS: Primary AL type localised amyloidosis involves local accumulation of monoclonal plasma cells and their secreted products, as in nodular cutaneous amyloidosis. Localised AL type nodular amyloidosis is a separate entity in amyloidosis.  相似文献   
4.
Human epidermal growth factor receptor (HER) family proteins are currently major targets of therapeutic monoclonal antibodies against various epithelial cancers. However, the resistance of cancer cells to HER family-targeted therapies, which may be caused by cancer heterogeneity and persistent HER phosphorylation, often reduces overall therapeutic effects. We herein showed that a newly discovered molecular complex between CD98 and HER2 affected HER function and cancer cell growth. The immunoprecipitation of the HER2 or HER3 protein from lysates of SKBR3 breast cancer (BrCa) cells revealed the HER2-CD98 or HER3-CD98 complex. The knockdown of CD98 by small interfering RNAs inhibited the phosphorylation of HER2 in SKBR3 cells. A bispecific antibody (BsAb) that recognized the HER2 and CD98 proteins was constructed from a humanized anti-HER2 (SER4) IgG and an anti-CD98 (HBJ127) single chain variable fragment, and this BsAb significantly inhibited the cell growth of SKBR3 cells. Prior to the inhibition of AKT phosphorylation, BsAb inhibited the phosphorylation of HER2, however, significant inhibition of HER2 phosphorylation was not observed in anti-HER2 pertuzumab, trastuzumab, SER4 or anti-CD98 HBJ127 in SKBR3 cells. The dual targeting of HER2 and CD98 has potential as a new therapeutic strategy for BrCa.  相似文献   
5.
6.
PurposeWe have previously shown that maintenance of ATP levels is a promising strategy for preventing neuronal cell death, and that branched chain amino acids (BCAAs) enhanced cellular ATP levels in cultured cells and antagonized cell death. BCAAs attenuated photoreceptor degeneration and retinal ganglion cell death in rodent models of retinal degeneration or glaucoma. This study aimed to elucidate the mechanisms through which BCAAs enhance ATP production.MethodsIntracellular ATP concentration was measured in HeLa cells under glycolysis and citric acid cycle inhibited conditions. Next, glucose uptake was quantified in HeLa cells and in 661W retinal photoreceptor-derived cells under glycolysis inhibition, endoplasmic reticulum stress, and glucose transporters (GLUTs) inhibited conditions, by measuring the fluorescence of fluorescently labeled deoxy-glucose analog using flow cytometry. Then, the intracellular behavior of GLUT1 and GLUT3 were observed in HeLa or 661W cells transfected with enhanced green fluorescent protein-GLUTs.ResultsBCAAs recovered intracellular ATP levels during glycolysis inhibition and during citric acid cycle inhibition. BCAAs significantly increased glucose uptake and recovered decreased glucose uptake induced by endoplasmic reticulum stress or glycolysis inhibition. However, BCAAs were unable to increase intracellular ATP levels or glucose uptake when GLUTs were inhibited. Fluorescence microscopy revealed that supplementation of BCAAs enhanced the translocation of GLUTs proteins to the plasma membrane over time.ConclusionsBCAAs increase ATP production by promoting glucose uptake through promotion of glucose transporters translocation to the plasma membrane. These results may help expand the clinical application of BCAAs in retinal neurodegenerative diseases, such as glaucoma and retinal degeneration.  相似文献   
7.
8.
We describe a young Japanese woman who was diagnosed with Crohn's disease affecting the ileum, transverse colon, and rectum, as confirmed by barium studies, colonoscopy, and histopathological examination. Her father and sister also had Crohn's disease. After a 4-yr course of sulfasalazine and elemental diet therapy, she was readmitted for perianal abscess associated with the presence of pancytopenia, microhematuria with granular cast, hypocomplementemia, and high titers of autoimmune antibodies (anti-ANA and anti-dsDNA antibodies). Based on these features, a diagnosis of systemic lupus erythematosus (SLE) was made. Despite the rarity of such combination (Crohn's disease with SLE), patients with Crohn's disease who develop such clinical findings might need evaluation for SLE.  相似文献   
9.
Objective Classic Hodgkin lymphoma (CHL) has been regarded as a curable disease when treated appropriately, especially in younger patients, and ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine) has been regarded as the standard regimen. However, a relatively poor prognosis has been reported in older patients with CHL, and the efficacy and tolerability of the ABVD regimen has not been fully elucidated. We retrospectively investigated the outcomes in patients with CHL treated with ABVD at our institute. Methods Twenty-five patients were evaluated; 14 were ≤60 years of age, and 11 were >60 years of age (older group). Results The ABVD doses were reduced in all patients in the older group; the median average relative dose intensity was 0.58. In the older group, the 5-year overall survival (OS) and median OS were 100% and not reached, respectively, for patients with early-stage CHL and 66.7% and not reached, respectively, for those with advanced-stage CHL. No patients died of CHL, and only one treatment-related death was observed in the older group. Conclusion ABVD with dose attenuation may represent a feasible and effective strategy for the treatment of older patients with CHL in clinical practice, particularly in those with early-stage disease, although the optimal degree of attenuation remains unclear.  相似文献   
10.
Abstract: Although eosinophil infiltrate has been recognized in hepatic graft-versus-host disease, its significance in relation to hepatic graft-versus-host disease lesions is unknown. In the present study, we analyzed hepatic eosinophil infiltration in relation to bile duct damage in experimental mouse graft-versus-host disease across minor histocompatibility barriers up to 14 months after transplantation. Portal eosinophil infiltration was found from 1 week after transplantation throughout the entire 14-month observation period. It was most striking during the early chronic stage of hepatic graft-versus-host disease between 2 to 7 months, with a peak at 5 months after transplantation. Microscopic and electron microscopic study revealed eosinophils infiltrated around the bile duct as well as in the bile duct epithelial layer. They were commonly found together with lymphocytes but were also occasionally found singly around the bile duct and in the bile duct epithelial layer. Bile duct epithelial cells in contact with and in the vicinity of eosinophils showed a variety of degenerative changes, occasionally associated with the presence of extracellular eosinophil granules. Bile duct epithelial cells with eosinophil infiltration just beneath the basement membrane frequently showed further characteristic severe degenerative changes with shedding or dropping-off into the lumen, which features were quite similar to those seen in the bronchial epithelium in asthma patients. These results indicate that not only lymphocytes but also eosinophils may be involved in the production of the bile duct injury in hepatic graft-versus-host disease, especially in its early chronic stage.  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