全文获取类型
收费全文 | 1368篇 |
免费 | 85篇 |
国内免费 | 21篇 |
专业分类
耳鼻咽喉 | 10篇 |
儿科学 | 22篇 |
妇产科学 | 31篇 |
基础医学 | 196篇 |
口腔科学 | 23篇 |
临床医学 | 107篇 |
内科学 | 396篇 |
皮肤病学 | 12篇 |
神经病学 | 34篇 |
特种医学 | 139篇 |
外科学 | 162篇 |
综合类 | 9篇 |
预防医学 | 49篇 |
眼科学 | 6篇 |
药学 | 77篇 |
中国医学 | 2篇 |
肿瘤学 | 199篇 |
出版年
2023年 | 8篇 |
2022年 | 10篇 |
2021年 | 21篇 |
2020年 | 16篇 |
2019年 | 13篇 |
2018年 | 33篇 |
2017年 | 20篇 |
2016年 | 13篇 |
2015年 | 24篇 |
2014年 | 29篇 |
2013年 | 39篇 |
2012年 | 46篇 |
2011年 | 48篇 |
2010年 | 47篇 |
2009年 | 46篇 |
2008年 | 40篇 |
2007年 | 52篇 |
2006年 | 34篇 |
2005年 | 44篇 |
2004年 | 42篇 |
2003年 | 60篇 |
2002年 | 51篇 |
2001年 | 49篇 |
2000年 | 41篇 |
1999年 | 47篇 |
1998年 | 32篇 |
1997年 | 23篇 |
1996年 | 21篇 |
1995年 | 18篇 |
1994年 | 17篇 |
1993年 | 26篇 |
1992年 | 41篇 |
1991年 | 41篇 |
1990年 | 53篇 |
1989年 | 57篇 |
1988年 | 51篇 |
1987年 | 41篇 |
1986年 | 31篇 |
1985年 | 38篇 |
1984年 | 18篇 |
1983年 | 20篇 |
1982年 | 10篇 |
1981年 | 8篇 |
1980年 | 9篇 |
1979年 | 7篇 |
1978年 | 3篇 |
1977年 | 10篇 |
1976年 | 13篇 |
1973年 | 3篇 |
1965年 | 3篇 |
排序方式: 共有1474条查询结果,搜索用时 7 毫秒
41.
42.
Agnieszka Arthur Romana A Panagopoulos Lachlan Cooper Danijela Menicanin Ian H Parkinson John D Codrington Kate Vandyke Andrew CW Zannettino Simon A Koblar Natalie A Sims Koichi Matsuo Stan Gronthos 《Journal of bone and mineral research》2013,28(4):926-935
Previous reports have identified a role for the tyrosine kinase receptor EphB4 and its ligand, ephrinB2, as potential mediators of both bone formation by osteoblasts and bone resorption by osteoclasts. In the present study, we examined the role of EphB4 during bone repair after traumatic injury. We performed femoral fractures with internal fixation in transgenic mice that overexpress EphB4 under the collagen type 1 promoter (Col1‐EphB4) and investigated the bone repair process up to 12 weeks postfracture. The data indicated that Col1‐EphB4 mice exhibited stiffer and stronger bones after fracture compared with wild‐type mice. The fractured bones of Col1‐EphB4 transgenic mice displayed significantly greater tissue and bone volume 2 weeks postfracture compared with that of wild‐type mice. These findings correlated with increased chondrogenesis and mineral formation within the callus site at 2 weeks postfracture, as demonstrated by increased safranin O and von Kossa staining, respectively. Interestingly, Col1‐EphB4 mice were found to possess significantly greater numbers of clonogenic mesenchymal stromal progenitor cells (CFU‐F), with an increased capacity to form mineralized nodules in vitro under osteogenic conditions, when compared with those of the wild‐type control mice. Furthermore, Col1‐EphB4 mice had significantly lower numbers of TRAP‐positive multinucleated osteoclasts within the callus site. Taken together, these observations suggest that EphB4 promotes endochondral ossification while inhibiting osteoclast development during callus formation and may represent a novel drug target for the repair of fractured bones. © 2013 American Society for Bone and Mineral Research. 相似文献
43.
44.
Family members charged with the care of those suffering from schizophrenia experience considerable stress due to their multiple responsibilities. Research regarding the burdens of caregiving is scant in Hong Kong and China. The present study quantified the association of the duties of caregivers with mental health symptoms in two Asian cities having distinct health care systems (i.e., Hong Kong and Guangzhou, China). Thirty nine caregivers in Hong Kong and 70 caregivers in Guangzhou were recruited from nongovernmental mental health organizations. They were assessed using the Chinese version of the Involvement Evaluation Questionnaire and the General Health Questionnaire. While the Guangzhou family caregivers had a significantly higher burden than the Hong Kong sample, there was no significant difference in the psychological health status of family caregivers in the two cities. Result of correlational analyses, however, revealed high associations between burden of care variables and the psychological health of the caregivers. Findings for the present study have implications regarding the physical and mental health needs of those caring for seriously disturbed relatives. 相似文献
45.
Hideaki Teshima Naoto Nakamura Qin-Yi Li Yasuyuki Takata Koji Takahashi 《RSC advances》2020,10(73):44854
We report for the first time a zigzag-shaped gas phase at a highly-ordered pyrolytic graphite/water interface. The novel shape of the gaseous domain is triggered by the holes of the underlying solid-like layers, which are composed of air molecules. Specifically, many holes were created by heating in the thin solid-like layers, which roughened them. The gas domains that formed on these layers deformed from circular to zigzag-shaped as the contact lines expanded while avoiding the holes of the underlying layers. We explained the formation and growth processes of these gas structures in terms of thin film growth, which varies with the mobility of the constituent molecules.Heating induces the formation of novel zigzag gas phases on the holey adsorbed air layers. 相似文献
46.
47.
48.
49.
50.
Three-field dissection or two-field dissection?--A proposal of new algorithm for lymphadenectomy 总被引:3,自引:0,他引:3
Tabira Y Okuma T Sakaguchi T Kuhara H Teshima K Kawasuji M 《Hepato-gastroenterology》2004,51(58):1015-1020
BACKGROUND/AIMS: There are no systematic criteria for cervical lymphadenectomy in esophageal carcinoma. We provide a new algorithm for deciding whether to use three-field dissection or two-field dissection. METHODOLOGY: Ninety-eight patients underwent curative esophagectomies with three-field lymph node dissections for squamous cell carcinoma of the thoracic esophagus. We examined the outcomes and predictors for survival of these patients. Therefore, we devised a new decision tree for deciding whether to use three-field dissection or two-field dissection. RESULTS: The overall 5-year survival rate for the 98 patients was 41.3%. The number of positive nodes was the only significant predictor for survival in the multivariate Cox proportional hazard model. The outcomes of patients with positive supraclavicular/internal jugular nodes were poor. On the other hand, positive cervical paraesophageal nodes do not worsen prognosis. We provided a new algorithm for selecting procedure of lymphadenectomy based on the presence of lymph node metastases. This algorithm is decided by the number of positive nodes, the presence of cervical node metastasis and recurrent nerve node metastasis. According to this decision tree, there were a few patients who needed absolutely three-field dissections. CONCLUSIONS: The new algorithm may be helpful for deciding three-field dissection or two-field dissection for thoracic esophageal carcinoma. 相似文献