全文获取类型
收费全文 | 49090篇 |
免费 | 3838篇 |
国内免费 | 109篇 |
专业分类
耳鼻咽喉 | 468篇 |
儿科学 | 1835篇 |
妇产科学 | 1293篇 |
基础医学 | 6120篇 |
口腔科学 | 431篇 |
临床医学 | 6291篇 |
内科学 | 8879篇 |
皮肤病学 | 999篇 |
神经病学 | 5031篇 |
特种医学 | 960篇 |
外科学 | 5137篇 |
综合类 | 397篇 |
现状与发展 | 1篇 |
一般理论 | 86篇 |
预防医学 | 6949篇 |
眼科学 | 844篇 |
药学 | 3422篇 |
中国医学 | 60篇 |
肿瘤学 | 3834篇 |
出版年
2024年 | 57篇 |
2023年 | 512篇 |
2022年 | 814篇 |
2021年 | 1814篇 |
2020年 | 1106篇 |
2019年 | 1794篇 |
2018年 | 1902篇 |
2017年 | 1461篇 |
2016年 | 1551篇 |
2015年 | 1631篇 |
2014年 | 2294篇 |
2013年 | 2999篇 |
2012年 | 4508篇 |
2011年 | 4416篇 |
2010年 | 2410篇 |
2009年 | 1991篇 |
2008年 | 3452篇 |
2007年 | 3397篇 |
2006年 | 3159篇 |
2005年 | 2960篇 |
2004年 | 2556篇 |
2003年 | 2139篇 |
2002年 | 1870篇 |
2001年 | 212篇 |
2000年 | 144篇 |
1999年 | 215篇 |
1998年 | 301篇 |
1997年 | 216篇 |
1996年 | 176篇 |
1995年 | 155篇 |
1994年 | 115篇 |
1993年 | 100篇 |
1992年 | 67篇 |
1991年 | 49篇 |
1990年 | 47篇 |
1989年 | 53篇 |
1988年 | 35篇 |
1987年 | 26篇 |
1986年 | 25篇 |
1985年 | 25篇 |
1984年 | 38篇 |
1983年 | 37篇 |
1982年 | 16篇 |
1981年 | 21篇 |
1980年 | 21篇 |
1978年 | 21篇 |
1977年 | 14篇 |
1976年 | 14篇 |
1975年 | 16篇 |
1973年 | 16篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
Aaron M Kipp Jennifer A Lehman Richard A Bowen Patricia E Fox Michael R Stephens Kaci Klenk Nicholas Komar Michel L Bunning 《The American journal of tropical medicine and hygiene》2006,75(4):688-690
To better understand the potential environmental health risk presented by West Nile virus (WNV)-contaminated feces, we quantified the amount of WNV present in the feces of experimentally infected American crows (Corvus brachyrhynchos) and fish crows (Corvus ossifragus). Peak fecal titers ranged from 10(3.5) to 10(8.8) plaque-forming units (PFU)/g for 10 American crows and from 10(2.3) to 10(6.4) PFU/g for 10 fish crows. The presence of infectious WNV in bird feces indicates a potential for direct transmission of WNV. Thus, handlers of sick or dead birds should take appropriate precautions to avoid exposure to fecal material. 相似文献
62.
Jennifer M Griffith James R Sorenson J Michael Bowling Tracey Jennings-Grant 《Health education & behavior》2005,32(5):613-626
The Enhancing Patient Prenatal Education study tested the feasibility and educational impact of an interactive program for patient prenatal genetic screening and testing education. Patients at two private practices and one public health clinic participated (N = 207). The program collected knowledge and measures of anxiety before and after use of the tool. Time in various prenatal visit activities was collected prior to and after the introduction of the education tool. Providers completed an assessment of their experiences with patients who had used the program. Results indicate that patient knowledge significantly increased from pre to post (p = .0001) with no increase in anxiety (p = .31). Time in clinic activities, including overall visit time, increased. A majority of providers indicated that the program disrupted clinic flow. This assessment suggests that the program increases patient knowledge and does not increase patient anxiety. However, challenges remain to using this program in a clinic setting. 相似文献
63.
The purpose of this study was to determine the dosimetric impact of a neurosurgical titanium mesh in patients treated with 6- and 18-MV photon beams. The effects of a 0.4-mm-thick titanium mesh on the dose profile at 3 regions within a solid water phantom were measured using extended dose range-2 (EDR2) film for 6- and 18-MV photon beams. All measurements were performed with the titanium mesh placed at a depth of 1.5 cm in the phantom. Films were exposed immediately above the mesh, immediately below the mesh, and at a depth of 5 cm from the surface of the phantom. The films were scanned using a scanning densitometer. In the region directly above the titanium mesh, there was an increase in dose of 7.1% for 6-MV photons and 4.9% for 18-MV photons. Directly below the titanium mesh, there was an average decrease in dose of 1.5% for 6-MV photons and an increase of 1.0% for 18-MV photons. At 5-cm depth, for 6- and 18-MV photons, there was a decrease in dose of 2.2% and 0.6%, respectively. We concluded that for cranial irradiation with high-energy photons, the dosimetric impact of a 0.4-mm titanium mesh is small and does not require modification in treatment parameters. 相似文献
64.
65.
Balanced analgesia (an opioid and a nonsteroidal anti-inflammatory agent) after hysterectomy often leads to better postoperative pain outcomes. Researchers compared post-hysterectomy patients who received balanced analgesia with those who received only morphine patient-controlled analgesia, and their relationship with pain scores, ambulation, and hospital length of stay. 相似文献
66.
Neal G Palmer James R Yacyshyn Herbert C Northcott Brian Nebbe Paul W Major 《American journal of orthodontics and dentofacial orthopedics》2005,128(2):163-167
INTRODUCTION: To plan for future acceptance and implementation of computer-related technology, it is necessary to understand orthodontists' current perceptions and attitudes toward emerging technologies. METHODS: An anonymous, self-administered, mail-out survey of Canadian orthodontists was conducted. The response rate was 45.6% (304/667). RESULTS: Most orthodontists indicated that computer technology could improve current practice efficiency and quality of patient care. Only 15% reported that digital models are quite or very useful; 73.6%, 69.1%, 55%, and 37.4% agreed or strongly agreed with using digital and electronic technology to consult with other dental specialists, other orthodontists, general dentists, and the public, respectively. Cost of the technology was reported as a significant or insurmountable obstacle by 54% of the respondents. Interprovincial legislation, unclear consultation remuneration guidelines, and lack of comfort with the technology were not perceived as significant obstacles. Only 36% reported security or privacy issues as a significant or insurmountable obstacle. CONCLUSIONS: Canadian orthodontists seem to view digital and electronic technology as useful and capable of improving their offices' efficiency and production. Although they are sensitive to some potential obstacles, they are willing to overcome these and incorporate the technology into their practices. 相似文献
67.
68.
David Berrigan Linda W Pickle Jennifer Dill 《International journal of health geographics》2010,9(1):20
Background
Past studies of associations between measures of the built environment, particularly street connectivity, and active transportation (AT) or leisure walking/bicycling have largely failed to account for spatial autocorrelation of connectivity variables and have seldom examined both the propensity for AT and its duration in a coherent fashion. Such efforts could improve our understanding of the spatial and behavioral aspects of AT. We analyzed spatially identified data from Los Angeles and San Diego Counties collected as part of the 2001 California Health Interview Survey. 相似文献69.
70.