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   432篇
  免费   31篇
  国内免费   7篇
耳鼻咽喉   1篇
儿科学   25篇
妇产科学   3篇
基础医学   35篇
口腔科学   30篇
临床医学   59篇
内科学   70篇
皮肤病学   5篇
神经病学   16篇
特种医学   62篇
外科学   64篇
综合类   29篇
预防医学   30篇
药学   14篇
中国医学   4篇
肿瘤学   23篇
  2023年   2篇
  2022年   2篇
  2021年   14篇
  2020年   5篇
  2019年   5篇
  2018年   7篇
  2017年   9篇
  2016年   8篇
  2015年   15篇
  2014年   10篇
  2013年   18篇
  2012年   26篇
  2011年   17篇
  2010年   28篇
  2009年   12篇
  2008年   15篇
  2007年   11篇
  2006年   18篇
  2005年   18篇
  2004年   9篇
  2003年   3篇
  2002年   4篇
  2001年   3篇
  2000年   6篇
  1999年   4篇
  1998年   24篇
  1997年   14篇
  1996年   19篇
  1995年   8篇
  1994年   13篇
  1993年   9篇
  1992年   3篇
  1991年   8篇
  1990年   5篇
  1989年   11篇
  1988年   12篇
  1987年   16篇
  1986年   10篇
  1985年   6篇
  1984年   7篇
  1983年   3篇
  1982年   9篇
  1981年   2篇
  1980年   6篇
  1979年   1篇
  1978年   1篇
  1977年   3篇
  1976年   7篇
  1975年   2篇
  1971年   2篇
排序方式: 共有470条查询结果,搜索用时 15 毫秒
51.
52.
53.
54.
The more metastatic sites and bone marrow metastasis in small cell lung cancer (SCLC), the worse the prognosis. Diagnosing the bone marrow invasion at the beginning of the therapy is important for determining of the prognosis and planning the treatment. Abnormalities of some blood parameters may help to estimate the extent of bone marrow invasion by cancer cells. In this retrospective review, the changes in routine laboratory tests that may indicate bone marrow invasion, the predictive values of these tests, and the prognostic importance of bone marrow invasion were evaluated in SCLC patients who were being followed up according to a protocol. One hundred and forty‐four patients with SCLC were enrolled in this study. Retrospectively, it was evaluated that 25 (17.4%) of the patients had bone marrow metastasis. According to univariate analysis, there was a significant difference between hemoglobin, white blood cell count, platelet count, lactate dehydrogenase, alkaline phosphatase and uric acid of the patients with and without bone marrow involvement. Among the biochemical parameters, the elevated LDH and AP had the highest sensitivity and specificity as indicators of bone marrow invasion (0.80–0.82 and 0.84–0.78, respectively). The median overall survival of extensive‐stage disease with and without bone marrow metastasis were 4.0 ± 1.0 months (95% CI 2.2–5.7) and 7.0 ± 1.2 months (95% CI 4.7–9.3), respectively (P = 0.03). Bone marrow metastasis was found to be an indicator of a bad prognosis. Bone marrow biopsy, that is an invasive procedure, can be performed on selected patients who have changes of routine laboratory tests suggesting bone marrow invasion.  相似文献   
55.
56.
57.
Abstract – Human mononuclear cells purified by Lymphoprep flotation were incubated with phenytoin (PHT) (20 μg/ml) or its metabolite p-HPPH (2 μg/ml) in the presence of Concanaval-in A (10 μg/ml) in vitro. The results indicate that phenytoin and its metabolite p-HPPH induce the release of a mononuclear cell factor(s) that activates quiescent human gingival fibroblast to synthesize DNA.  相似文献   
58.
Yeates  A; Drayer  B; Heinz  ER; Osborne  D 《Radiology》1985,155(2):387-390
Digital subtraction angiography (DSA) of the spinal cord was performed in 6 patients using selective intra-arterial injections of contrast material. Two arteriovenous malformations of the spinal cord, 1 dural fistula, and 1 case of multiple hemangioblastomas were studied. Contrast and spatial resolution were satisfactory for defining normal and abnormal vascularity while reducing examination time, contrast dosage, patient discomfort, and film cost. The only significant limitation was misregistration artifacts seen on lateral views encompassing the diaphragm.  相似文献   
59.
Abstract Erythrocyte fatty acids and plasma vitamin E concentrations were determined in 47 grade 2 and 21 grade 3 malnourished Pakistani children (ages 4–56 months). Data were compared with those of 26 age- and sex-matched apparently healthy controls. Evaluation with three statistical approaches revealed that both grade 2 and grade 3 malnourished children had decreased erythrocyte ω6 fatty acids and to a lesser extent decreased ω3 fatty acids. These decreases were compensated for by increased ω9 fatty acids. The patients tended to have lower plasma vitamin E concentrations. We conclude that malnourished Pakistani children have low essential fatty acid status, notably those of the ω6 series. The combination of low erythrocyte 22:6ω3 and a low 22:5ω6/22:4ω6 ratio in grade 2 patients suggests low Δ4-desaturation activity, which may be due to impaired peroxisomal β-oxidation.  相似文献   
60.
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