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   682篇
  免费   39篇
  国内免费   3篇
耳鼻咽喉   1篇
儿科学   18篇
妇产科学   3篇
基础医学   120篇
口腔科学   4篇
临床医学   59篇
内科学   186篇
皮肤病学   10篇
神经病学   48篇
特种医学   9篇
外科学   97篇
综合类   1篇
预防医学   27篇
眼科学   5篇
药学   39篇
中国医学   7篇
肿瘤学   90篇
  2023年   2篇
  2022年   6篇
  2021年   9篇
  2020年   11篇
  2019年   14篇
  2018年   20篇
  2017年   8篇
  2016年   13篇
  2015年   12篇
  2014年   23篇
  2013年   34篇
  2012年   49篇
  2011年   56篇
  2010年   22篇
  2009年   29篇
  2008年   43篇
  2007年   50篇
  2006年   30篇
  2005年   33篇
  2004年   49篇
  2003年   42篇
  2002年   26篇
  2001年   7篇
  2000年   10篇
  1999年   10篇
  1998年   5篇
  1997年   7篇
  1996年   5篇
  1995年   3篇
  1994年   6篇
  1993年   7篇
  1992年   14篇
  1991年   11篇
  1990年   5篇
  1989年   7篇
  1988年   5篇
  1987年   4篇
  1986年   8篇
  1985年   3篇
  1984年   2篇
  1983年   2篇
  1979年   4篇
  1976年   2篇
  1974年   2篇
  1973年   2篇
  1971年   2篇
  1968年   1篇
  1967年   1篇
  1965年   1篇
  1958年   2篇
排序方式: 共有724条查询结果,搜索用时 15 毫秒
1.
Clonality in autoimmune diseases   总被引:1,自引:0,他引:1  
  相似文献   
2.
Disseminated intravascular coagulation masking neonatal hemophilia   总被引:2,自引:0,他引:2  
Most infants with hemophilia have no bleeding in the neonatal period even if birth trauma occurs. The explanation for this lack of bleeding in the first few days of life in most hemophiliacs is unknown. Maternal factors VIII and IX fail to cross the placenta and cannot, therefore, protect the neonate. There have, however, been an increasing number of reports of severe neonatal bleeding in hemophiliac neonates. Herein, a case of severe neonatal bleeding responsible for hypovolemic shock and disseminated intravascular coagulation masking the hemophilia and delaying its diagnosis is reported. Transfusion of twice the total globular mass and exchange-transfusion were required. Hemorrhagic gastric necrosis occurred, requiring subtotal gastrectomy. The diagnosis of severe hemophilia A (factor VIII = 1%) was established only at 17 days of age. At the age of five months, the child developed a dumping syndrome which improved under appropriate dietary therapy and finally resolved. Outcome was favorable and at the evaluation at two years of age the child was leading a normal life. This case underlines the difficulty of the diagnosis of hemophilia at birth. When there is no family history of bleeding, the diagnosis of hemophilia is usually missed in the neonatal period and established only later or retrospectively. Factors VIII and IX should consequently be measured in male neonates with unusual bleeding and an increased activated partial thromboplastin time, even if disseminated intravascular coagulation is present. Prompt diagnosis and initiation of specific therapy may lessen acute morbidity and prevent long-term sequelae in affected infants.  相似文献   
3.
4.
In order to analyze the place of dialysis in a hemodialysis/transplantation program, the duration of each treatment modality, mortality rate and quality of inclusion in the social network were studied. Complications which arose during hemodialysis were evaluated by comparing the 1970's and the 1980's. Sixty children with terminal renal failure, aged 3 to 15 years, were entered in a hemodialysis/transplantation program between May 1971 and December 1988. Patients were followed up until December 1989. Among the 47 (78%) survivors at the end of the follow-up period, 25 had a functioning renal transplant and 22 were undergoing dialysis. Among the 13 deaths, 7 occurred during renal transplantation or immediately after loss of the transplant and 6 occurred under dialysis. Mean duration of treatment, including both dialysis and transplantation, was 7 years 11 months. Mean time spent under dialysis was 4 years 9 months. Time spent with a functioning transplant was 3 years 10 months for the 46 transplant recipients. Mean time spent on the transplant waiting list fell from 3 years 6 months before 1980 to 2 years after 1980. Virtually no cases of renal osteodystrophy, acute arterial hypertension or hepatitis B were seen after 1980 as a result of the use of higher-potency vitamin D derivatives, recent antihypertensive drugs including ACE inhibitors, and the Hevac B vaccine. Similarly, safety and patient comfort during dialysis improved substantially, as well as the quality of rehabilitation. Growth remained a significant problem although improvements can be expected to occur in the near future. Hemodialysis is an indispensable complement to transplantation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
5.
6.
Helicobacter pylori has been associated with the development of two malignant diseases: gastric adenocarcinoma and gastric mucosa-associated lymphoid tissue (MALT) lymphoma. Although the cag pathogenicity island, especially the cagA gene, has been linked with adenocarcinoma, few data concerning H. pylori pathogenic factors involved in low-grade gastric MALT lymphoma are available. The goal of this study was to analyze the prevalence of and correlation between genes coding for seven H. pylori virulence factors (cagA, cagE, vacA, iceA, babA, hopQ, and oipA) and two novel adhesins (sabA and hopZ) by comparing a collection of 43 H. pylori strains isolated from patients with low-grade gastric MALT lymphoma to 39 strains isolated from age-matched patients with gastritis only. Our results show that taken individually, none of the nine genes tested can be considered associated with MALT strains and allow us to conclude that MALT pathogenesis is not linked with more proinflammatory H. pylori strains. We demonstrated that in patients infected with strains harboring the iceA1 allele, sabA functional status, and hopZ "off" status, the odds of developing a MALT lymphoma were 10 times higher. However, the low prevalence of such strains (10 of 43 MALT strains) renders this triple association a low-sensitivity marker for MALT strains. Our data confirmed that H. pylori virulence factors are correlated with one another. If the involvement of H. pylori in MALT lymphoma is well established, the pathomechanism by which gastric lymphoma occurs remains to be identified.  相似文献   
7.
We report a case of a 42-yr-old woman with Langerhans cell histiocytosis (LCH) confined to the thyroid and associated with lymphocytic thyroiditis and a papillary microcarcinoma. This patient remains free of symptoms 14 mo after surgery. Thyroid LCH is rare. In children, it usually occurs as part of a multisystemic disease, whereas it is usually exclusive in adults. Isolated thyroid LCH is frequently associated with another thyroid disease, especially lymphocytic thyroiditis, suggesting that it is a reactive process rather than a neoplastic proliferation. The prognosis of isolated thyroid LCH is good. However, because it can rarely precede or reveal a multisystemic disease, additional investigations as well as a prolonged follow-up are justified.  相似文献   
8.
BACKGROUND: Failure to resist chronic obsessive-compulsive symptoms may denote an altered state of cognitive control. We searched for the cerebral regions engaged in this dysfunction. METHOD: Differences in brain regional activity were examined by event-related functional magnetic regional imaging (fMRI) in a group of adolescents or young adults (n = 12) with childhood-onset obsessive-compulsive disorder (OCD), relative to healthy subjects. Subjects performed a conflict task involving the presentation of two consecutive and possibly conflicting prime and target numbers. Patients' image dataset was further analysed according to resistance or non-resistance to symptoms during the scans. RESULTS: Using volume correction based on a priori hypotheses, an exploratory analysis revealed that, within the prime-target repetition condition, the OCD subjects activated more than healthy subjects a subregion of the anterior cingulate gyrus and the left parietal lobe. Furthermore, compared with 'resistant' patients, the 'non-resistant' OCD subjects activated a bilateral network including the precuneus, pulvinar and paracentral lobules. CONCLUSIONS: Higher regional activations suggest an abnormal amplification process in OCD subjects during the discrimination of repetitive visual stimuli. The regional distribution of functional changes may vary with the patients' ability to resist obsessions.  相似文献   
9.
The La(SSB) antigen has been detected within the cytoplasm and on the membrane of conjunctival cells (CC) from patients with Sjögren's syndrome, whereas it was weakly expressed in the nucleus of normal cells. The diseased CC were shown to overproduce major histocompatibility complex (MHC) class I antigens and express MHC class II antigens. Anti-heat-shock protein monoclonal antibody bound to the cell membrane in patients but not in normal controls.On sabbatical leave from Department of Internal Medicine, Medical School, Ioannina, Greece.  相似文献   
10.
In conventional mice, the T cell receptor (TCR)αβ+ CD8αα+ and CD8αβ+ subsets of the intestinal intraepithelial lymphocytes (IEL) constitute two subpopulations. Each comprise a few hundred clones expressing apparently random receptor repertoires which are different in individual genetically identical mice (Regnault, A., Cumano, A., Vassalli, P., Guy-Grand, D. and Kourilsky, P., J. Exp. Med. 1994. 180: 1345). We analyzed the repertoire diversity of sorted CD8αα and CD8αβ+ IEL populations from the small intestine of individual germ-free mice that contain ten times less TCRαβ+ T cells than conventional mice. The TCRβ repertoire of the CD8αα and the CD8αβ IEL populations of germ-free adult mice shows the same degree of oligoclonality as that of conventional mice. These results show that the intestinal microflora is not responsible for the repertoire oligoclonality of TCRαβ+ IEL. The presence of the microflora leads to an expansion of clones which arise independently of bacteria. To evaluate the degree of expansion of IEL clones in conventional mice, we went on to measure their clone sizes in vivo by quantitative PCR in the total and in adjacent sections of the small intestine of adult animals. We found that both the CD8αα and the CD8αβ TCRαβ IEL clones have a heterogeneous size pattern, with clones containing from 3 × 103 cells up to 1.2 × 106 cells, the clones being qualitatively and quantitatively different in individual mice. Cells from a given IEL clone are not evenly distributed throughout the length of the small intestine. The observation that the TCRαβ IEL populations comprise a few hundred clones of very heterogeneous size and distribution suggests that they arise from a limited number of precursors, which may be slowly but continuously renewed, and undergo extensive clonal expansion in the epithelium.  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