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   1972篇
  免费   141篇
  国内免费   4篇
耳鼻咽喉   23篇
儿科学   87篇
妇产科学   15篇
基础医学   150篇
口腔科学   88篇
临床医学   158篇
内科学   390篇
皮肤病学   52篇
神经病学   138篇
特种医学   64篇
外科学   324篇
综合类   40篇
预防医学   94篇
眼科学   64篇
药学   234篇
中国医学   7篇
肿瘤学   189篇
  2024年   2篇
  2023年   22篇
  2022年   50篇
  2021年   93篇
  2020年   43篇
  2019年   68篇
  2018年   69篇
  2017年   60篇
  2016年   71篇
  2015年   76篇
  2014年   87篇
  2013年   140篇
  2012年   215篇
  2011年   187篇
  2010年   90篇
  2009年   93篇
  2008年   142篇
  2007年   99篇
  2006年   98篇
  2005年   109篇
  2004年   88篇
  2003年   76篇
  2002年   59篇
  2001年   7篇
  2000年   5篇
  1999年   9篇
  1998年   10篇
  1997年   6篇
  1996年   10篇
  1995年   5篇
  1994年   6篇
  1993年   2篇
  1992年   1篇
  1991年   2篇
  1989年   2篇
  1986年   1篇
  1985年   1篇
  1982年   3篇
  1981年   1篇
  1979年   3篇
  1978年   1篇
  1977年   1篇
  1976年   1篇
  1969年   1篇
  1965年   2篇
排序方式: 共有2117条查询结果,搜索用时 218 毫秒
1.
Object Intracranial aneurysms are rare in children and have different epidemiological, clinical, and morphological characteristics and outcome from those in adults. Materials and methods We analyzed demographic, clinical, radiologic features, treatment, and outcome in 55 patients <18 years of age, treated from Jan 1995 through December 2005. Results Intracranial aneurysms in children below 18 years constituted 4% of all intracranial aneurysms. Internal Carotid artery (ICA) bifurcation was the commonest location. About half of the aneurysms were complex. Three-fourth of the patients required surgical treatment. Two patients died, constituting 5% mortality. Two patients (5%) had poor outcome, whereas the majority (90%) had a favorable outcome. Conclusions Pediatric aneurysms have male predominance, higher incidence of clinical features of mass effect or seizures, high incidence of large, traumatic/mycotic aneurysms, associated illnesses and ICH/IVH and hydrocephalus, better Hunt and Hess grades at presentation, ICA bifurcation as the commonest site, and better outcome than their adult counterparts.  相似文献   
2.
3.
4.
We describe herein the rare case of a hydatid cyst found in the breast of a 26-year-old woman. Clinically, the mass was at first suspected of being a fibroadenoma, but fine needle aspiration cytology (FNAC) yielded clear fluid only. Histopathologic examination of the resected speciman confirmed that it was a hydatid cyst.  相似文献   
5.
We report the case of an 8-year-old boy with a parotid mass diagnosed to be a leiomyosarcoma. Considering the unresectable extent of the mass, the patient was subjected to radiotherapy. The patient developed distant metastasis following the course of radiotherapy and was put on chemotherapy. The child was lost to further follow up. To our knowledge, this is the first reported case in the English-language literature of such an entity in the pediatric age group.  相似文献   
6.
Lung disease is a prominent cause of morbidity and mortality worldwide. When a patient has a common lung disease, such as asthma, or a less prevalent one, such as idiopathic pulmonary fibrosis, psychiatric issues should be considered as an integral part of the care plan for each patient. There have been many studies of psychologic factors and psychiatric syndromes in various lung diseases and their treatment. In this article, the authors focus on an evidence-based approach to reviewing this clinical literature.  相似文献   
7.
The cause of the circadian variation in the incidence of acute myocardial infarction (AMI) has not been identified. Tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) have opposing effects on thrombi. Hence, the extent of the clot, the size of the infarct and outcome of patients could depend on t-PA and PAI-1 levels. In an effort to elucidate the pathophysiologic basis of circadian variation of AMI, we investigated the presence of a possible corresponding circadian variation in the levels of endogenous t-PA and PAI-1 in patients diagnosed to have AMI and the effects of hypertension, diabetes and site of the infarct on these levels. We estimated the levels of t-PA and PAI-1 in platelet-poor plasma of 42 patients with AMI on admission, using the enzyme-linked immunosorbant assay. Although not statistically significant, patients having an AMI in the morning hours had the highest t-PA:PAI-1 ratio. The normal circadian variation in PAI-1 levels was lost in patients with AMI, probably due to the disease process. Also, the t-PA levels in hypertensive patients were significantly lower than in nonhypertensives. PAI-1 levels were also significantly lower in patients with anteroseptal than in inferior and anterolateral AMI. This relationship between the fibrinolytic potential and the site of infarction needs further study. Furthermore, t-PA levels on admission were significantly lower in survivors and may have a predictive value in determining the outcome.  相似文献   
8.
A 58-year-old male presented with fatigue, tiredness, and pruritus after hot showers and an elevated white blood cell count (20000/mm(3)). A diagnosis of polycythemia vera (PV) was made after investigation revealed a low erythropoietin and elevated leukocyte alkaline phosphatase (LAP) score; he was treated with repeated phlebotomies. Two years later he developed elevated white counts again and investigation revealed Philadelphia chromosome positive (19/20 cells) chronic myelocytic leukemia (CML). The karyotype also revealed trisomy 9 in 1 of 20 cells. He was treated with imatinib mesylate and went into clinical, hematologic, cytogenetic, and molecular remission. Repeat chromosomal analysis revealed absence of Philadelphia chromosome and BCR/ABL translocation but presence of trisomy 9. To our knowledge, this is the first reported case of coexisting PV and CML both associated with separate chromosomal abnormalities. This also raises an interesting therapeutic consideration of using concomitant imatinib mesylate and hydroxyurea.  相似文献   
9.
Homozygote hypotransferrinaemic mice (hpx/hpx) have cytopathological features similar to those of human congenital atransferrinaemia, genetic haemochromatosis, and neonatal haemochromatosis. These conditions all have in common high levels of cytotoxic non-transferrin-bound serum iron. This study describes the ultrastructural features of iron overload in liver, pancreas, heart, and small intestine of 2- and 12-month-old hypotransferrinaemic mice. Electron microscopic studies of unstained sections showed early parenchymal cell siderosis, with accumulation of numerous ferritin particles and clusters in the cytosol, as well as ferritin and haemosiderin in lysosomes (siderosomes). In the 12-month-old animals, iron was also found in Kupffer cells and macrophages in other tissues. In addition, there were conspicuous iron-containing compounds in the bile canaliculi, and marked iron deposition in the pancreas and heart. Laser microprobe mass analysis (LAMMA) enabled localization and relative quantitation of iron deposition in subcellular compartments providing in situ documentation of iron accumulation in siderosomes and contributed in assessing total cytosolic iron in various cell types. Moreover, it demonstrated the importance and magnitude of the biliary route for iron excretion in these animals.  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