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   2739篇
  免费   189篇
  国内免费   18篇
耳鼻咽喉   16篇
儿科学   69篇
妇产科学   75篇
基础医学   485篇
口腔科学   17篇
临床医学   289篇
内科学   587篇
皮肤病学   38篇
神经病学   263篇
特种医学   45篇
外科学   340篇
综合类   24篇
一般理论   3篇
预防医学   225篇
眼科学   73篇
药学   197篇
中国医学   12篇
肿瘤学   188篇
  2023年   9篇
  2022年   43篇
  2021年   59篇
  2020年   40篇
  2019年   69篇
  2018年   65篇
  2017年   48篇
  2016年   46篇
  2015年   51篇
  2014年   83篇
  2013年   125篇
  2012年   188篇
  2011年   181篇
  2010年   101篇
  2009年   99篇
  2008年   171篇
  2007年   199篇
  2006年   174篇
  2005年   170篇
  2004年   166篇
  2003年   143篇
  2002年   167篇
  2001年   28篇
  2000年   29篇
  1999年   25篇
  1998年   24篇
  1997年   22篇
  1996年   16篇
  1995年   19篇
  1994年   12篇
  1993年   12篇
  1992年   14篇
  1991年   11篇
  1990年   14篇
  1989年   10篇
  1988年   25篇
  1987年   18篇
  1986年   9篇
  1985年   19篇
  1984年   8篇
  1981年   20篇
  1980年   13篇
  1979年   17篇
  1978年   14篇
  1976年   11篇
  1974年   8篇
  1973年   10篇
  1972年   8篇
  1971年   12篇
  1954年   8篇
排序方式: 共有2946条查询结果,搜索用时 15 毫秒
1.
2.
ABSTRACT Freud's paper on the Schreber Case is considered from a contemporary perspective drawing on the object relations theorists. Some of Winnicott's ideas are used to illustrate how one might understand Schreber's predicament today. Although Freud's views on the role of repressed homosexual longings in the aetiology of Schreber's illness are not endorsed his prescience in the search for meaning in the patient's discourse is applauded.  相似文献   
3.
4.
The polymerization of lactides with various D /L enantiomeric compositions using achiral Schiff's base/aluminium methoxide as initiator (SALENAlOCH3) in dichloromethane solution at 70°C is reported. The conversion was kept below 70% in order to limit transesterification reactions. The polymers obtained after precipitation show a narrow molecular weight distribution (ratio of weight- to number-average molecular weights M w/M n = 1,1–1,2) and an optical rotation higher than that expected from the optical purity of the starting monomers. The examination of the thermal properties reveals that whatever their enantiomeric composition all the prepared polymers are crystalline. This unusual behavior is explained by an end-chain propagation mechanism producing stereocopolymers with long enantiomeric sequences, i.e., increased isotacticity as substantiated by an examination of the microstructure of the polymers by means of 13C nuclear magnetic resonance. A stereocomplex formation was observed for stereocopolymers with optical purities below 40%.  相似文献   
5.
Buruli's ulcer is a real disease of public health. In Ivory Coast, 50 patients were treated from February 1987 to August 1991. It realizes a real destruction of skin and subcutaneous tissues. The germ is Mycobacterium ulcerans. The preferential localisation is the limbs in children of 14 years old. Large ulcer with polycyclic margin are treated by extended excision and thin skin grafts. But deformities persist after the surgical treatment. Hospitalisation is long and drugs are expensive.  相似文献   
6.
The physiopathology of combined volvulus of sigmoid and small intestine is discussed. In many cases a half-knot is involved, that is to say a "key" between the two ileal and sigmoid loops, difficult to describe with words but easy to understand by the use of a diagram and radiologic and intraoperative images of lesions, of possible assistance when releasing the loops or determining site of section of foot of occluded loops. Of 116 cases of sigmoid volvulus treated in the Treihville hospital, Abidjan between 1972 and 1983, eleven were associated with small intestine volvulus. Of these 11 cases, 9 were treated by emergency ideal colectomy and small intestine resection, with 3 deaths, and 2 by emergency ideal colectomy and small intestine reintegration, with 2 deaths. Operative mortality was therefore high (45%), global mortality being 24%. This is inherent in underdeveloped surgical units and will certainly improve greatly as hospital standing improves.  相似文献   
7.
8.
9.
The activation of a predominant T-helper-cell subset plays a critical role in disease resolution. In the case of Toxoplasma gondii, the available evidence indicates that CD4+ protective cells belong to the Th1 subset. The aim of this study was to determine whether T. gondii antigens (in T. gondii sonicate [TSo]) presented by splenic dendritic cells (DC) were able to induce a specific immune response in vivo and to protect CBA/J mice orally challenged with T. gondii cysts. CBA/J mice immunized with TSo-pulsed DC exhibited significantly fewer cysts in their brains after oral infection with T. gondii 76K than control mice did. Protected mice developed a strong humoral response in vivo, with especially high levels of anti-TSo immunoglobulin G2a antibodies in serum. T. gondii antigens such as SAG1 (surface protein), SAG2 (surface protein), MIC1 (microneme protein), ROP2 through ROP4 (rhoptry proteins), and MIC2 (microneme protein) were recognized predominantly. Furthermore, DC loaded with TSo, which synthesized high levels of interleukin-12 (IL-12), triggered a strong cellular response in vivo, as assessed by the proliferation of lymph node cells in response to TSo restimulation in vitro. Cellular proliferation was associated with gamma interferon and IL-2 production. Taken together, these results indicate that immunization of CBA/J mice with TSo-pulsed DC can induce both humoral and Th1-like cellular immune responses and affords partial resistance against the establishment of chronic toxoplasmosis.  相似文献   
10.
A/J and C57BL/6J mice behave differently in tests for alcohol preference, open-field activity, defecation in the open field, cricket attacking, and rope climbing. Chimeric mice, i.e., mice containing both A/J cells and C57BL/6J cells, were constructed and tested for these behaviors. Patterns of behavior among A/JC57BL/6J chimeras are such as to suggest that none of these behavior differences is controlled by a single cell or clone and that the same cell population that gives rise to the strain difference in alcohol preference also gives rise to the differences in open-field activity and defecation, while separate cell populations control cricket killing and rope climbing.This research was supported by Research Grants AA 00388 and HD 03015 to M. N. N. and MH 18996 to K. B. Computing assistance was obtained from the Health Sciences Computing Facility, UCLA, supported by NIH Special Research Resources Grant RR-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