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   662篇
  免费   22篇
  国内免费   7篇
耳鼻咽喉   4篇
儿科学   14篇
妇产科学   5篇
基础医学   115篇
口腔科学   8篇
临床医学   54篇
内科学   186篇
皮肤病学   6篇
神经病学   70篇
特种医学   20篇
外科学   49篇
综合类   8篇
预防医学   17篇
眼科学   6篇
药学   43篇
中国医学   2篇
肿瘤学   84篇
  2023年   2篇
  2022年   5篇
  2021年   14篇
  2020年   8篇
  2019年   10篇
  2018年   12篇
  2017年   6篇
  2016年   8篇
  2015年   13篇
  2014年   25篇
  2013年   20篇
  2012年   41篇
  2011年   40篇
  2010年   11篇
  2009年   13篇
  2008年   29篇
  2007年   19篇
  2006年   33篇
  2005年   28篇
  2004年   21篇
  2003年   36篇
  2002年   27篇
  2001年   20篇
  2000年   28篇
  1999年   24篇
  1998年   11篇
  1997年   15篇
  1996年   6篇
  1995年   8篇
  1994年   9篇
  1993年   6篇
  1992年   14篇
  1991年   5篇
  1990年   11篇
  1989年   7篇
  1988年   12篇
  1987年   9篇
  1986年   11篇
  1985年   10篇
  1983年   3篇
  1979年   26篇
  1978年   8篇
  1977年   3篇
  1976年   4篇
  1974年   3篇
  1973年   4篇
  1968年   3篇
  1966年   2篇
  1965年   1篇
  1956年   1篇
排序方式: 共有691条查询结果,搜索用时 15 毫秒
1.
A 10-year-old girl with autoimmune hepatitis (AIH) was reported. She was admitted to our hospital because of cholestasis and elevation of liver enzymes for 2 months. Laboratory examination revealed that EBV-DNA copy number in the PBMNC (peripheral mononuclear cells) was 1.2 x 10(3) copies/microg of DNA, hypergammaglobulinemia, and positive antinuclear antibody, positive anti-smooth muscle antibody. The histology of her liver biopsy specimen revealed interface hepatitis, dense mononuclear cell infiltrates, mild fibrosis, and negative for EBV in situ hybridization assay indicating AIH and not EBV-associated hepatitis. She was treated firstly with methylprednisolone pulses, then will prednisolone p.o.+azathioprine p.o.. Intravenous cyclophosphamide pulse therapy was introduced because of her abnormal immune pathology. All abnormal laboratory parameters improved to normal levels within 2 months, and EBV-DNA copy number in the PBMNC became negative after 4 months. The histology of liver biopsy specimen was useful for the diagnosis of AIH in such a difficult case needed to be differentiated from EBV hepatitis.  相似文献   
2.
We report a case of aspergillosis in the subdural space and frontal lobe in an 83-year-old man. The clinical course simulated that of a brain tumor. The source for the infection was considered to be the previous burr-hole surgery for chronic subdural hematoma, which was performed 2.5 years before the onset of symptoms. The patient was treated by removal of the abscess and granuloma. The clinical features and treatment of aspergillosis after neurosurgical procedures are discussed.  相似文献   
3.
We have developed an isolated spinal cord-skin preparation of the newborn rat. The spinal cord together with a piece of skin connected to the cord by the saphenous nerve was isolated from 1- to 4-day-old rats and separately superfused with artificial cerebrospinal fluid in two neighbouring chambers. Potentials were recorded extracellularly from the third lumbar ventral root. Application of capsaicin (0.5-2 μM) or KCl (60–350 mM) with brief pressure pulses to the perfusion bath of the skin evoked a depolarizing response of 20- to 40-s duration in the ventral root. The response was depressed by [Met5]enkcphalin (0.03–3 μM). morphine (0.1–2 μM) and a tachykinin antagonist, [D-Arg1,D-Trp7,9,Leu11] substance P (spantide), 1–10 μM), applied to the spinal cord by superfusion, whereas the response was augmented by centrally administered calcitonin gene-related peptide (0.1–0.2 μM) or bicuculline (0.5–1 μM).  相似文献   
4.
5.
6.
7.
The immunoperoxidase method, the autoclave method, and a newly developed alkaline-guanidine method were used to distinguish senile (SSA) and familial types (FAP) of prealbumin-related amyloidosis in formalin-fixed, paraffin-embedded tissue sections. Because all the amyloid deposits of SSA and FAP reacted positively with the antiprealbumin antiserum, a classification of the amyloid fibril proteins of FAP and SSA by immunohistochemistry, using polyclonal anti-prealbumin antisera, was not feasible. Both the senile and familial forms of amyloidosis showed unchanged Congophilia after prolonged autoclaving. In the alkaline-guanidine method, FAP amyloids were resistant to incubation for 2 hours. On the other hand, amyloid deposits of SSA lost the Congophilia and green birefringence with 2 hours' alkaline-guanidine treatment. Therefore, the autoclave method combined with the alkaline-guanidine method will considerably facilitate differentiation of SSA and FAP, without specific antisera.  相似文献   
8.
Summary To identify amyloid deposits in the anterior pituitary gland, we have immunohistochemical, histochemical and alkaline Congo red staining. The anti-human P component reacted positively with these amyloid deposits, while antisera against prealbumin, AA type amyloid fibril protein and various anterior pituitary hormones were negative. A combination of Congo red and anti-human P component staining was most sensitive and reliable for detection of amyloid in the anterior pituitary glands of 300 randomly autopsied patients. Amyloid deposits increased in parallel with the age of the patients, however, they appeared earlier and more frequently than heretofore reported. Deposition of amyloid was seen initially in the 3rd decade and the positivity rate of amyloid deposits was 73% in the 5th decade. The histochemical characteristics of these pituitary amyloid deposits differed from those of cerebral and systemic deposits, particularly those found in the amyloid of senile systemic amyloidosis.This study was supported in part by a grant from the Fundation for Advancement of Clinical Medicine and Ministry of Health and Welfare of Japan  相似文献   
9.
Streptococcus pyogenes thiol proteinase, also known as streptococcal pyrogenic exotoxin B (SpeB), has been suggested to be a major virulence factor in S. pyogenes infection. SpeB was reported to induce apoptosis of host cells, but its mechanism of action is not yet fully understood. In this study, we examined the involvement of matrix metalloproteinases (MMPs) in SpeB-induced apoptosis. We first developed a large-scale preparation of recombinant SpeB and precursors of human MMP-9 and -2 (proMMPs) by using Escherichia coli Rosetta (DE3)pLysS and baculovirus-insect cell expression systems, respectively. Treatment with SpeB induced effective proteolytic activation of both proMMP-9 and -2. When RAW264 murine macrophages were incubated with SpeB-activated proMMP-9, the level of tumor necrosis factor alpha (TNF-alpha) in conditioned medium (CM), assessed by an enzyme immunoassay, was elevated. This increase was completely inhibited by addition of the MMP inhibitor SI-27 to the cell culture. The CM also produced marked induction of apoptosis of U937 human monocytic cells. Similarly, soluble Fas ligand (sFasL) was detected in CM of cultures of SW480 cells expressing FasL after treatment with SpeB-activated proMMPs; this CM also induced apoptosis in U937 cells. SpeB had a direct effect as well and caused the release of TNF-alpha and sFasL from the cells. SpeB-dependent production of MMP-9 and -2 and proapoptotic molecules (TNF-alpha and sFasL) was evident in a murine model of severe invasive S. pyogenes infection. These results suggest that SpeB or SpeB-activated MMPs contribute to tissue damage and streptococcal invasion in the host via extracellular release of TNF-alpha and sFasL.  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