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   16865篇
  免费   912篇
  国内免费   52篇
耳鼻咽喉   219篇
儿科学   452篇
妇产科学   196篇
基础医学   2070篇
口腔科学   631篇
临床医学   1482篇
内科学   3241篇
皮肤病学   335篇
神经病学   1787篇
特种医学   1276篇
外国民族医学   1篇
外科学   2450篇
综合类   151篇
一般理论   4篇
预防医学   1475篇
眼科学   323篇
药学   860篇
中国医学   14篇
肿瘤学   862篇
  2021年   201篇
  2020年   123篇
  2019年   151篇
  2018年   237篇
  2017年   188篇
  2016年   213篇
  2015年   272篇
  2014年   383篇
  2013年   498篇
  2012年   694篇
  2011年   720篇
  2010年   477篇
  2009年   421篇
  2008年   728篇
  2007年   824篇
  2006年   737篇
  2005年   733篇
  2004年   659篇
  2003年   640篇
  2002年   638篇
  2001年   641篇
  2000年   593篇
  1999年   484篇
  1998年   227篇
  1997年   176篇
  1996年   168篇
  1995年   193篇
  1994年   156篇
  1993年   137篇
  1992年   342篇
  1991年   370篇
  1990年   309篇
  1989年   300篇
  1988年   281篇
  1987年   239篇
  1986年   259篇
  1985年   265篇
  1984年   208篇
  1983年   184篇
  1982年   129篇
  1981年   124篇
  1980年   119篇
  1979年   242篇
  1978年   155篇
  1977年   153篇
  1975年   155篇
  1974年   127篇
  1973年   135篇
  1972年   141篇
  1970年   117篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
81.
Four patients with intracranial aneurysm clips made from a variety of alloys were studied without incidence by MR imaging at field strengths ranging from 0.35 to 0.6 T. Knowledge of the type of alloy used in the manufacturing of an aneurysm clip is important in determining whether the clip will or will not deflect in a magnetic field. Ferromagnetic clips show deflection and torque in a magnetic field and have the potential to dislodge from the aneurysm. Nonferromagnetic or weakly ferromagnetic aneurysm clips such as the Sugita (Elgiloy), Yasargil (316 LVM stainless steel), Heifetz (Elgiloy), Yasargil (Phynox), and Vari-Angle McFadden (MP35N) do not deflect or deflect weakly in the magnetic field and therefore would not be expected to dislodge during MR. The option of imaging many patients with intracranial aneurysm clips with MR extends the usefulness of the technique to a previously excluded population.  相似文献   
82.
Infections of the developing brain.   总被引:1,自引:0,他引:1  
  相似文献   
83.
Follow-up of patients 1 year after deep dorsal vein resection gives evidence of an approximate 50-60% success rate. A careful selection of only this small percentage of patients, in whom abnormal drainage through the penile dorsum is obvious, is mandatory. Men with an arterial cofactor have to be excluded or to be subsequently treated by intracavernosal autoinjection of vasoactive substances. Late results from our study demonstrate a further loss of sufficient erection, also in men considered as persistent success by us, in the subjective view of the patient and/or his sexual partner.  相似文献   
84.
85.
86.
The tripeptide N alpha-carbamoyl-L-methionyl-L-leucyl-L-phenylalanine methyl ester has been synthesized in solution by classical methods and fully characterized. This compound, prepared in order to obtain a deeper insight into the mode of binding at the formyl peptide chemotactic receptor, has been tested for its ability to induce granule enzyme secretion from rabbit peritoneal neutrophils and found to be a complete agonist. These results confirm the hypothesis that a proton on the N alpha-blocking group of the tripeptide forms a hydrogen bond with an acceptor in the binding site.  相似文献   
87.
This study was undertaken to examine the success rate and the length of orthodontic treatment of impacted maxillary canines in adult patients. A sample of 19 adults (mean age, 28.8 +/- 8.6 years; range, 20-47 years), who had been treated for a total of 23 impacted maxillary canines, was compared with a younger control group (mean age, 13.7 +/- 1.3 years; range, 12-16 years). The control subjects were chosen for a similar degree of impaction difficulty by carefully matching the positions of the impacted canines in the 3 planes of space. The success rate among the adults was 69.5% compared with 100% among the younger controls. The lower success rate was due to 5 canines that had failed to erupt and 2 canines that had been partially extruded but could not be aligned in the arch. The duration of treating the overall malocclusion of the adults and young subjects did not materially differ. However, the adults showed significant increases in the duration and number of treatment visits required for resolving the canine impaction, in both the simpler and the more difficult cases. When further divided by age, all the failed canines were found in the older (over 30) adult subgroup. It was concluded that the prognosis for successful orthodontic resolution of an impacted canine in an adult is lower than that in a younger patient and that the prognosis worsens with age. Furthermore, when such treatment is undertaken, its successful completion should be expected to take considerably longer.  相似文献   
88.
89.
Thyroglossal Cysts and Sinuses   总被引:1,自引:1,他引:0       下载免费PDF全文
  相似文献   
90.
Bigger numbers needed!   总被引:1,自引:0,他引:1  
  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