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   994篇
  免费   39篇
  国内免费   3篇
耳鼻咽喉   2篇
儿科学   75篇
妇产科学   12篇
基础医学   80篇
口腔科学   54篇
临床医学   92篇
内科学   253篇
皮肤病学   21篇
神经病学   17篇
特种医学   254篇
外科学   43篇
综合类   10篇
预防医学   45篇
眼科学   5篇
药学   34篇
中国医学   1篇
肿瘤学   38篇
  2020年   3篇
  2018年   12篇
  2017年   10篇
  2016年   8篇
  2015年   10篇
  2014年   18篇
  2013年   22篇
  2012年   16篇
  2011年   6篇
  2010年   36篇
  2009年   40篇
  2008年   25篇
  2007年   16篇
  2006年   21篇
  2005年   16篇
  2004年   14篇
  2003年   16篇
  2002年   10篇
  2001年   9篇
  2000年   6篇
  1999年   13篇
  1998年   50篇
  1997年   67篇
  1996年   49篇
  1995年   42篇
  1994年   52篇
  1993年   51篇
  1992年   9篇
  1991年   10篇
  1990年   12篇
  1989年   40篇
  1988年   40篇
  1987年   33篇
  1986年   34篇
  1985年   33篇
  1984年   14篇
  1983年   22篇
  1982年   17篇
  1981年   18篇
  1980年   22篇
  1979年   6篇
  1978年   9篇
  1977年   12篇
  1976年   9篇
  1975年   17篇
  1974年   5篇
  1973年   6篇
  1972年   4篇
  1971年   7篇
  1970年   4篇
排序方式: 共有1036条查询结果,搜索用时 15 毫秒
991.
992.
Fracture nonunion: CT assessment with multiplanar reconstruction   总被引:2,自引:0,他引:2  
Nineteen patients with suspected or possible fracture nonunion underwent computed tomography (CT) with multiplanar reconstruction (MPR). Each case represented a difficult problem in fracture management in which clinical and conventional radiographic examinations had failed to provide a definitive diagnosis. CT with MPR demonstrated nonunion in 13 of 19 cases by delineating the lack of bone bridging across the fracture site in multiple planes. Variable amounts bridging were detected in six cases, indicating partial healing or delayed union. Evaluation of fracture healing with MPR was possible despite remaining metal hardware (ten cases), multiple operations (15 cases), or bone grafting (five cases). CT with MPR aided surgical planning and affected treatment options by providing a more detailed assessment of malalignment and angular deformities, the magnitude of the gap in bone, and the integrity of the adjacent weight-bearing joints in multiple projections. It is an important new modality for evaluating fracture nonunion.  相似文献   
993.
The transketolase activity (TKA) of the white and red blood cells of oral contraceptive users was studied in an unselected sample population. Compared with healthy controls of corresponding age, the white cell TKA in the oral contraceptive groups was lowered in about 30%. The red cell TKA was lowered in about 15% of the subjects studied. The most pronounced TKA inactivation was observed in the group taking pills that contained mestranol and megestrol acetate. The glucose tolerance tests were normal. Discontinuing the hormones normalized the white cell TKA.  相似文献   
994.
A predictable increase in the proliferative rate of malignant cells remaining after initial cytoreduction in vivo forms the rationale for timed sequential therapy (TST) with 1-B-D-arabinofuranosylcytosine (ara- C) for adult acute myelogenous leukemia (AML). The relationship between in vivo leukemic cell growth, intracellular ara-C metabolism, and clinical response to ara-C-containing TST was evaluated by comparing AML marrow cell growth kinetic and biochemical pharmacologic determinants obtained before therapy (day 0) and at the predicted peak of in vivo postdrug residual tumor proliferation (day 8). Serial measurements of DNA synthesis and net intracellular ara-C metabolism demonstrated marked increases in both determinants in day 8 residual tumor when compared with the pretreatment cells for newly diagnosed adults achieving complete remission but not for TST-refractory patients. The interrelationship of AML cell proliferation and biochemical pharmacology together quantitate cytotoxicity measured by both achievement and duration of remission and serve to predict eventual clinical outcome in response to TST with ara-C where both growth and favorable pharmacokinetics are intrinsic to the success of the drug schedule.  相似文献   
995.
Left azygos lobe   总被引:1,自引:0,他引:1  
Takasugi  JE; Godwin  JD 《Radiology》1989,171(1):133-134
Left azygos lobe is much rarer than right azygos lobe, but cases have been reported. Computed tomography proved more reliable than plain radiography in the diagnosis of left azygos lobe in a 10-year-old girl.  相似文献   
996.
997.
The volumes of the left ventricle (LV) and right ventricle (RV) were determined by scintigraphy, radiography, and weight, using hollow, morphologically accurate cardiac phantoms that ranged from 99-415 ml (RV) and 72-364 ml (LV). Self-attenuation within these simulated ventricles appeared negligible in view of the nearly linear correlation between scintigraphic and weight determined volumes. Scintigraphy compared favorably with radiography for estimating clinically encountered volumes of the RV and LV.  相似文献   
998.
The purpose of this study was to evaluate the reproducibility of the Periodontal Treatment Need System (PTNS), when plaque retentions were examined separately. A sample of 8000 persons was drawn to represent the Finnish population aged 30 yr and over. The first clinical examination (total sample) was made by a specially trained expanded-duty dental auxiliary (EDDA). During the second examination (2-6 months later), 20% of the total sample was reexamined by a dentist, and of those, every 6th patient was examined by the EDDA. Reproducibility of the PTNS was assessed as intra- and interexaminer agreement and was calculated using Cohen's kappa and weighted kappa. The intraexaminer weighted kappa values were 0.67 +/- 0.05 for the PTNS and 0.48 +/- 0.15 for plaque retentions. The interexaminer weighted kappa values between the PTNS registrations were 0.77 +/- 0.05 and 0.74 +/- 0.12 in plaque retentions when examinations were made within 1 day, and 0.53 +/- 0.05 and 0.37 +/- 0.07, respectively, when the interexaminer registrations were made with an interval of 2-6 months between them. The kappa values for intra- and interexaminer reliability reflect quite high reproducibility.  相似文献   
999.
The solitary renal calyx and papilla in human kidneys   总被引:1,自引:0,他引:1  
  相似文献   
1000.
The hyperplastic cholecystoses: cholesterolosis and adenomyomatosis   总被引:3,自引:0,他引:3  
  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