全文获取类型
收费全文 | 55853篇 |
免费 | 3493篇 |
国内免费 | 110篇 |
专业分类
耳鼻咽喉 | 533篇 |
儿科学 | 2306篇 |
妇产科学 | 1514篇 |
基础医学 | 6976篇 |
口腔科学 | 540篇 |
临床医学 | 8578篇 |
内科学 | 9628篇 |
皮肤病学 | 759篇 |
神经病学 | 5362篇 |
特种医学 | 977篇 |
外科学 | 4611篇 |
综合类 | 589篇 |
一般理论 | 109篇 |
预防医学 | 7774篇 |
眼科学 | 761篇 |
药学 | 3647篇 |
1篇 | |
中国医学 | 61篇 |
肿瘤学 | 4730篇 |
出版年
2024年 | 86篇 |
2023年 | 327篇 |
2022年 | 450篇 |
2021年 | 1039篇 |
2020年 | 725篇 |
2019年 | 1051篇 |
2018年 | 1203篇 |
2017年 | 977篇 |
2016年 | 1059篇 |
2015年 | 1238篇 |
2014年 | 1712篇 |
2013年 | 2729篇 |
2012年 | 3930篇 |
2011年 | 4245篇 |
2010年 | 2357篇 |
2009年 | 2128篇 |
2008年 | 3836篇 |
2007年 | 4081篇 |
2006年 | 3933篇 |
2005年 | 4078篇 |
2004年 | 3872篇 |
2003年 | 3642篇 |
2002年 | 3363篇 |
2001年 | 473篇 |
2000年 | 355篇 |
1999年 | 482篇 |
1998年 | 688篇 |
1997年 | 612篇 |
1996年 | 483篇 |
1995年 | 482篇 |
1994年 | 427篇 |
1993年 | 339篇 |
1992年 | 244篇 |
1991年 | 210篇 |
1990年 | 187篇 |
1989年 | 198篇 |
1988年 | 188篇 |
1987年 | 169篇 |
1986年 | 162篇 |
1985年 | 163篇 |
1984年 | 186篇 |
1983年 | 169篇 |
1982年 | 215篇 |
1981年 | 207篇 |
1980年 | 155篇 |
1979年 | 94篇 |
1978年 | 112篇 |
1977年 | 52篇 |
1976年 | 57篇 |
1974年 | 68篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
22.
Francesco Versace David W. Frank Elise M. Stevens Menton M. Deweese Michele Guindani Susan M. Schembre 《Psychophysiology》2019,56(4)
While some individuals can defy the lure of temptation, many others find appetizing food irresistible. The goal of this study was to investigate the neuropsychological mechanisms that increase individuals' vulnerability to cue‐induced eating. Using ERPs, a direct measure of brain activity, we showed that individuals with larger late positive potentials in response to food‐related cues than to erotic images are more susceptible to cue‐induced eating and, in the presence of a palatable food option, eat more than twice as much as individuals with the opposite brain reactivity profile. By highlighting the presence of individual brain reactivity profiles associated with susceptibility to cue‐induced eating, these findings contribute to the understanding of the neurobiological basis of vulnerability to obesity. 相似文献
23.
24.
“This illness diminishes me. What it does is like theft”: A qualitative meta‐synthesis of people's experiences of living with asthma 下载免费PDF全文
25.
26.
Sewell J Hawley N Kingsley K O'Malley S Ancajas CC 《Journal of dental education》2008,72(11):1261-1267
As the U.S. population continues to become more diverse, there has been a movement toward the recruitment of more diverse students into the dental profession. The purpose of this study was to assess the current and historical trends in diversity among dental school applicants and enrollees at a new dental institution, the University of Nevada, Las Vegas, School of Dental Medicine (UNLV-SDM). Applicant and enrollment data for the first four cohorts, sorted by gender and ethnicity, were retrieved and summarized by the Office of Admissions and Student Affairs at UNLV-SDM. The principal findings of this analysis revealed enrollment of females at UNLV-SDM was relatively consistent during this time interval, although significantly lower than the U.S. average of all dental schools. The enrollment of minorities at UNLV-SDM, however, was consistent and comparable to the U.S. average, although these percentages were disproportionately smaller than the percentage of minorities in the general population. Based upon these findings, a new model for outreach and recruitment of females and minorities was recently created, based in part upon evidence of successful strategies by dental educators at other institutions, in order to increase the enrollment of female and underrepresented minority students. 相似文献
27.
28.
29.
Beck JD Couper DJ Falkner KL Graham SP Grossi SG Gunsolley JC Madden T Maupome G Offenbacher S Stewart DD Trevisan M Van Dyke TE Genco RJ 《Journal of periodontology》2008,79(1):90-96
BACKGROUND: During the last 15 years, a substantial number of population-based, clinical, laboratory, and animal studies have been published that reported findings on the relationship between periodontal disease and cardiovascular disease. The Periodontitis and Vascular Events (PAVE) pilot study was conducted to investigate the feasibility of a randomized secondary prevention trial to test whether treatment of periodontal disease reduces the risk for cardiovascular disease. This article describes the occurrence of adverse events during the pilot study. METHODS: The PAVE pilot study was a multicenter, randomized trial comparing periodontal therapy to community dental care. Baseline and follow-up clinic visits included a periodontal examination; blood, subgingival plaque, and crevicular fluid specimen collection; and medical and dental histories. Telephone follow-up contacts were scheduled to occur 3 months after randomization and every 6 months thereafter to assess adverse events or endpoints. RESULTS: Cardiovascular adverse events occurred with similar frequency (23 versus 24 [P = 0.85] in the community control and the treatment groups, respectively). There were 15 serious adverse events (SAEs) with a non-significantly higher percentage occurring in the community care group (6.6% versus 3.3%; P = 0.19). A time-to-event analysis of patterns of SAEs indicated that subjects in the periodontal therapy group tended to be less likely to experience an SAE over the entire 25 months of the study. CONCLUSION: For those individuals who remained in the study, it appears that provision of periodontal scaling and root planing treatment to individuals with heart disease resulted in a similar pattern of adverse events as seen in the community care group, which also received some treatment. 相似文献
30.
Susan Schuster DDS George Eliades DDS DrDent Spiros Zinelis PhD Theodore Eliades DDS MS DrMed PhD T. Gerard Bradley BDS MS 《American journal of orthodontics and dentofacial orthopedics》2004,126(6):399-728
The objectives of this study were to investigate the structure of Invisalign appliances (Align Technology, Santa Clara, Calif) after intraoral exposure, and to qualitatively and quantitatively characterize the substances leached from the aligners after accelerated in vitro aging. Samples of Invisalign appliances were randomly selected from 10 patients before intraoral placement and after retrieval, and the prepared specimens were subjected to (1) bright-field optical reflection microscopy to study the surface morphology; (2) Fourier transform infrared microspectroscopy to characterize the in vivo changes in molecular composition induced on appliance surfaces, (3) scanning electron microscopy and energy dispersive X-ray microanalysis to identify the elemental composition of integuments formed on the surface, and (4) Vickers hardness (HV 200) testing. Another set of reference and retrieved appliances was subjected to artificial aging for 2 weeks, and the extracts were subjected to gas chromatography-mass spectroscopy. The retrieved appliances demonstrated substantial morphological variation relative to the as-received specimens involving abrasion at the cusp tips, adsorption of integuments, and localized calcification of the precipitated biofilm at stagnation sites. Buccal segments of retrieved appliances showed an increase in hardness, which might be attributed to mastication-induced cold work; however, the clinical implication of this effect on mechanotherapy is unknown. In vitro aged and retrieved appliances were found to leach no traceable amount of substances in an ethanol aging solution. 相似文献