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   5089篇
  免费   442篇
  国内免费   11篇
耳鼻咽喉   31篇
儿科学   179篇
妇产科学   126篇
基础医学   688篇
口腔科学   92篇
临床医学   454篇
内科学   1297篇
皮肤病学   112篇
神经病学   463篇
特种医学   233篇
外科学   725篇
综合类   56篇
预防医学   379篇
眼科学   116篇
药学   298篇
中国医学   14篇
肿瘤学   279篇
  2023年   33篇
  2022年   57篇
  2021年   146篇
  2020年   109篇
  2019年   152篇
  2018年   170篇
  2017年   149篇
  2016年   144篇
  2015年   146篇
  2014年   178篇
  2013年   224篇
  2012年   312篇
  2011年   276篇
  2010年   161篇
  2009年   167篇
  2008年   202篇
  2007年   245篇
  2006年   226篇
  2005年   242篇
  2004年   171篇
  2003年   164篇
  2002年   119篇
  2001年   124篇
  2000年   112篇
  1999年   113篇
  1998年   63篇
  1997年   50篇
  1996年   50篇
  1995年   40篇
  1994年   37篇
  1993年   40篇
  1992年   120篇
  1991年   109篇
  1990年   105篇
  1989年   100篇
  1988年   84篇
  1987年   66篇
  1986年   69篇
  1985年   52篇
  1984年   38篇
  1983年   40篇
  1982年   26篇
  1980年   17篇
  1979年   30篇
  1978年   28篇
  1977年   19篇
  1974年   19篇
  1972年   16篇
  1969年   18篇
  1966年   15篇
排序方式: 共有5542条查询结果,搜索用时 788 毫秒
1.
2.
3.
In order to assess the state and pathology of the woman's pelvis minor, a number of methods are commonly used among practitioners, encompassing clinical exploration, radiology, MRN, urodynamics, endoscopy and echography.

Echography has been poorly used in clinical pelvic exploration and its reliability is actually a matter of controversy 1. However, echographic surveys can provide us with valuable gynecological data on the state and pathologies of the soft pelvis, within the genital regions or even going beyond them, i.e. the rectal channel, bladder, urethra, anus, vascular plexuses, and all of their supporting tissues.

At our research unit, we have been employing Transvaginal Ultrasound echography (TVU) for a long time in conjunction with other pelvis-focused methods in order to study different kinds of pelvic alterations. TVU has proven to be friendly to use, fast, harmless and inexpensive, allowing serial explorations and producing high-quality dynamic images (loop-cinema, video-tape). Furthermore, this method is fairly aseptic in that the occurrence of faeces in the rectal ampolla is not a nuisance but a bonus in tracking the contours of the rectum walls and other topographical features which would be otherwise difficult to survey.

A complete pelvic floor TVU may add no longer than 5-8 minutes to a routine gynecological examination, can be implemented by the general gynecologist and generates data that can be further studied by the appropriate specialist for a more insightful evaluation 2.  相似文献   
4.
5.
6.
Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence.  相似文献   
7.
8.
9.
Platelet-derived growth factor (PDGF) and insulin-like growth factor I (IGF-I) in combination have previously been shown to enhance periodontal regeneration. The objective of this study was to further characterize the biological effects of this combination of growth factors in non-human primates and compare the effects to those of each growth factor individually. Ligature-induced periodontitis was initiated in 10 cynomolgus monkeys. After periodontal lesions were established, surgery was performed, and either a methylcellulose gel vehicle or vehicle containing 10 μg each of either PDGF-BB, IGF-I or both PDGF-BB and IGF-I was applied to exposed root surfaces. Biopsies were taken 4 and 12 wk after treatment and the extent of periodontal regeneration was assessed by histomorphometry. At both 4 and 12 wk vehicle-treated lesions generally revealed minimal osseous defect fill (ODF) (8.5±2.1% and 14.5±5.7%, respectively) and new attachment (NA) (34.1±5.2% and 26.6±10.5%, respectively). IGF-I treatment did not significantly alter healing compared to vehicle in any parameter at both 4 and 12 wk. PDGFBB-treated sites exhibited significant (p<0.05) regeneration of NA (69.6±12.0%) at 12 wk; trends for PDGF-BB treatment effect were also observed in other parameters at 4 and 12 wk. although these increases were not statistically significant. Treatment with PDGF-BB/IGF-I resulted in 21.6±5.1 % and 42.5±8.3% ODF at 4 and 12 wk, respectively, and 64.1±7.7% and 74.6±7.4% NA at 4 and 12 wk, respectively (all significantly greater than vehicle, p<0.05). The results from this study demonstrated that: 1) IGF-1 alone at the dose tested did not significantly alter periodontal wound healing; 2) PDGF-BB alone significantly stimulated NA, with trends of effect on other parameters; and 3) the PDGF-BB/IGF-I combination resulted in significant increases in NA and ODF above vehicle at both 4 and 12 wk.  相似文献   
10.
Isolated sperm from normo-, oligo- and astheno-spermic men were incubated for 20 h in medium supplemented with 8% heat-inactivated or untreated human serum, and in medium with heated or untreated serum deficient in complement factor C3. Before and after incubation, sperm motility was assessed by means of a computer-assisted semen analyser. The results did not show significant differences between the motility of sperm incubated in heated or untreated serum. It is concluded that heating of homologous serum is not necessary for preserving sperm motility and in some cases may even be disadvantageous.  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