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   5640篇
  免费   390篇
  国内免费   15篇
耳鼻咽喉   44篇
儿科学   176篇
妇产科学   139篇
基础医学   936篇
口腔科学   80篇
临床医学   547篇
内科学   1014篇
皮肤病学   243篇
神经病学   436篇
特种医学   198篇
外国民族医学   2篇
外科学   946篇
综合类   15篇
一般理论   1篇
预防医学   439篇
眼科学   76篇
药学   473篇
中国医学   6篇
肿瘤学   274篇
  2022年   36篇
  2021年   88篇
  2020年   74篇
  2019年   76篇
  2018年   106篇
  2017年   77篇
  2016年   104篇
  2015年   118篇
  2014年   128篇
  2013年   230篇
  2012年   295篇
  2011年   346篇
  2010年   201篇
  2009年   220篇
  2008年   311篇
  2007年   343篇
  2006年   317篇
  2005年   282篇
  2004年   260篇
  2003年   270篇
  2002年   237篇
  2001年   130篇
  2000年   126篇
  1999年   118篇
  1998年   76篇
  1997年   53篇
  1996年   44篇
  1995年   40篇
  1994年   35篇
  1993年   31篇
  1992年   79篇
  1991年   63篇
  1990年   78篇
  1989年   53篇
  1988年   44篇
  1987年   52篇
  1986年   53篇
  1985年   65篇
  1984年   42篇
  1983年   34篇
  1982年   29篇
  1981年   30篇
  1979年   38篇
  1978年   33篇
  1977年   35篇
  1976年   35篇
  1975年   30篇
  1973年   35篇
  1971年   34篇
  1969年   30篇
排序方式: 共有6045条查询结果,搜索用时 15 毫秒
1.
An association between juvenile xanthogranuloma (JXG), neurofibromatosis type 1 (NF1), and juvenile myelomonocytic leukemia (JMML) has been described in the literature but has only been documented in approximately 20 cases. We diagnosed a patient with NF1 at 25 months of age, before any cutaneous stigmata of this disease had appeared, because we decided to screen for the NF1 gene mutation because of his presentation with multiple JXGs and moderate macrocephaly (2.5 standard deviations) at 9 months of age and JMML diagnosed at 20 months of age. The child is well today after treatment with chemotherapy and allogenic bone marrow transplantation. With increased awareness, patients with JXG and NF1 who develop symptoms possibly related to JMML, such as paleness, skin bleeding, cough, unexplained fever, and hepatosplenomegaly, should be further evaluated. We also emphasize that multiple JXG lesions can be an early marker of NF1.  相似文献   
2.
3.
4.
5.
The induction of a granulomatous inflammation by jellyfish toxins is rare. More typically, acute toxic and urticarial reactions are seen. An 11-year-old boy developed a striated urticarial erythema on the left cheek after contact with a gelatinous mass while swimming in the sea in Croatia. After initial erosion, a striated induration developed in the area of contact. Histological examination revealed a granulomatous inflammation with some eosinophils. While topical steroid-based antiinflammatory and antibacterial therapy over several weeks was not effective, topical therapy with tacrolimus 0.1% for two two-week treatment periods led to healing of the skin changes with a slight scar. There was no clinical recurrence after 5 month of follow-up.  相似文献   
6.
7.
8.
Estrogen receptor (ER) and progesterone receptor (PR) contents were determined by biochemical (dextran charcoal-coated (DCC) assay) and immunohistochemical (ICA) methods in biopsies from 145 primary endometrial adenocarcinomas and those with eligible receptor measurements were analyzed with respect to correlations to cancer-specific survival in a multivariate analysis including histopathological characteristics. Median patient follow-up time was 67 months with 18 cancer deaths. The PR-DCC and ER-DCC values were dichotomized according to levels previously found by us to correspond to the best agreement between receptor status as determined by the DCC and ICA methods (130 fmol/mg cytosol protein for ER, 114 fmol/mg for PR). Using these thresholds, we found by multivariate analysis that “high” PR-DCC levels (>114 fmol/mg) correlated significantly (P= 0.004) with survival, independent of stage risk group (Ia + b vs Ic-IV). Patient age and histologic grade were prognostic factors in a univariate setting, but these parameters were eliminated in the multivariate model. While the PR-ICA scores also correlated significantly and independently with survival, the predictive effect of PR-ICA positivity alone could not be statistically evaluated due to the number of cases with eligible ICA values. However, we suggest that owing to a close correlation between DCC and ICA results, PR-ICA status may provide significant prognostic information when DCC measurements are not available.  相似文献   
9.
The pharmacokinetics and haemodynamic effects of isosorbide dinitrate (ISDN) have been investigated following administration of single doses as a sublingual (SL) spray (2.5 mg), sublingual tablet (5 mg) and peroral tablet (10 mg) in a randomised, placebo-controlled double-blind cross-over trial in 16 healthy volunteers.After the sublingual spray Cmax was higher (39.0 ng·ml-1) and tmax was shorter (3.9 min) than after the sublingual (22.8 ng·ml-1 and 13.8 min) and peroral (16.9 ng·ml-1 and 25.6 min) tablets. The AUC of ISDN did not differ following any of the three formulations (1031; 879; 997 ng·ml-1·min, for the spray, SL tablet and PO-tablet, respectively). Mononitrate metabolites of ISDN (IS-2-MN and IS-5-MN) and total nitrates in plasma increased in proportion to the administered dose. This indicates that the fraction of the dose absorbed was the same for all the formulations but that the extent of first-pass metabolism increased in the order sublingual spray < sublingual tablet < peroral tablet. Thus, compared to the spray, the relative bioavailability of ISDN was 48% and 28% from the sublingual and peroral tablets, respectively.The haemodynamic effects were quantified using the a/b ratio of the finger pulse wave and the systolic blood pressure and heart rate under orthostatic conditions. For the a/b ratio of the finger pulse, the maximal effect was higher (emax=130%) and the time to emax (temax) shorter (16.6 min) after the spray than the sublingual tablet (84.4% and 25.5 min) or peroral tablet (90.2 and 31.3 min). The onset of effect was within 3, 5 and 7.5 min after the spray, sublingual and peroral tablets, respectively. A larger change in the orthostatically-induced decrease in systolic blood pressure and increase in heart rate was obtained following peroral than sublingual administration despite the similar plasma concentrations of ISDN. This probably reflects the larger amount of pharmacodynamically active mononitrate metabolites formed after oral dosing. The integrated effect following administration of 2.5 mg ISDN as spray was similar to that of a sublingual tablet of 5 mg.  相似文献   
10.
Unilateral posterior chamber intraocular lens (IOL) implantation was performed after phacoemulsification or extracapsular cataract extraction in ten of 11 patients with phakodonesis or lens subluxation, which was bilateral in two cases. To facilitate placement of the IOL, the anterior capsule was opened with a YAG laser in nine patients. Intraoperative vitrectomy was performed in two patients, and posterior chamber IOL implantation was accomplished with fixation in the ciliary sulcus. Postoperative follow-up studies failed to demonstrate significant decentration or dislocation of the IOLs. Phakodonesis and lens subluxation are no longer considered absolute contraindications to implantation of posterior chamber IOLs.  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