全文获取类型
收费全文 | 331篇 |
免费 | 34篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 5篇 |
妇产科学 | 6篇 |
基础医学 | 34篇 |
口腔科学 | 8篇 |
临床医学 | 41篇 |
内科学 | 61篇 |
皮肤病学 | 8篇 |
神经病学 | 21篇 |
特种医学 | 63篇 |
外科学 | 29篇 |
综合类 | 1篇 |
预防医学 | 13篇 |
眼科学 | 2篇 |
药学 | 44篇 |
中国医学 | 3篇 |
肿瘤学 | 34篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 1篇 |
2020年 | 4篇 |
2019年 | 7篇 |
2018年 | 6篇 |
2017年 | 11篇 |
2016年 | 12篇 |
2015年 | 9篇 |
2014年 | 13篇 |
2013年 | 26篇 |
2012年 | 11篇 |
2011年 | 12篇 |
2010年 | 24篇 |
2009年 | 17篇 |
2008年 | 11篇 |
2007年 | 22篇 |
2006年 | 11篇 |
2005年 | 8篇 |
2004年 | 7篇 |
2003年 | 6篇 |
2002年 | 8篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1998年 | 12篇 |
1997年 | 12篇 |
1996年 | 7篇 |
1995年 | 8篇 |
1994年 | 6篇 |
1993年 | 12篇 |
1992年 | 14篇 |
1991年 | 3篇 |
1990年 | 3篇 |
1989年 | 12篇 |
1988年 | 9篇 |
1987年 | 7篇 |
1986年 | 5篇 |
1985年 | 1篇 |
1984年 | 6篇 |
1983年 | 3篇 |
1982年 | 6篇 |
1981年 | 1篇 |
1980年 | 5篇 |
1979年 | 1篇 |
1977年 | 3篇 |
1976年 | 1篇 |
1975年 | 2篇 |
1971年 | 1篇 |
排序方式: 共有378条查询结果,搜索用时 15 毫秒
61.
62.
63.
The technique of field potentials (FPs) provides a macroscopic view for exploring brain function, and is supplementary to single-unit recording, a microscopic view that investigates each neuron in great detail. Mapping the rat tail in the ventroposterolateral (VPL) nucleus of the thalamus was carried out by analyzing the current source density (CSD) of the evoked FPs. The results showed a clear somatotopic organization of the tail in the VPL nucleus. Also, to obtain high-fidelity FPs, two recording parameters were determined. Based upon cross-correlation coefficient (rho), the cycles of FPs needed to be averaged should not be less than 50 and the distance between the two recording sites should be no longer than 50 mum in each direction (mediolateral, anteroposterior and ventrodorsal). Under these conditions, the representation (or reproducibility) of an FP can be >95%. The procedures used to determine these parameters can serve as a guide to obtain FPs with high signal-to-noise ratio and without spatial aliasing error. 相似文献
64.
This study combined bone-conducted vibration (BCV) stimulation with triaxial accelerometry to correlate the acceleration magnitudes of BCV stimuli with ocular vestibular-evoked myogenic potential (oVEMP) test results. Fourteen healthy volunteers underwent oVEMP test using BCV stimuli with simultaneous monitoring the triaxial acceleration. All (100%) subjects exhibited clear oVEMPs in response to BCV stimuli from a vibrator. The lowest acceleration magnitudes for eliciting oVEMPs along the x-, y- and z-axes were 0.05±0.01 g, 0.16±0.08 g, and 0.04±0.01 g, respectively, exhibiting significantly higher acceleration magnitude along the y-axis than those along the x- and z-axes. In addition, significantly positive correlations were noted between the acceleration magnitude along each axis and the oVEMP amplitude. In conclusion, measuring the acceleration magnitude throughout oVEMP testing revealed a significant correlation between linear acceleration and oVEMP responses. Restated, increasing acceleration magnitude may have more synchronization of firing of vestibular afferents, resulting in more synchronized evoked potentials and greater oVEMP amplitude. 相似文献
65.
This study examined whether radiology report format influences reading time and comprehension of information. Three reports
were reformatted to conventional free text, structured text organized by organ system, and hierarchical structured text organized
by clinical significance. Five attending radiologists, five radiology residents, five internal medicine attendings, and five
internal medicine residents read the reports and answered a series of questions about them. Reading was timed and participants
reported reading preferences. For reading time, there was no significant effect for format, but there was for attending versus
resident, and radiology versus internal medicine. For percent correct scores, there was no significant effect for report format
or for attending versus resident, but there was for radiology versus internal medicine with the radiologists scoring better
overall. Report format does not appear to impact viewing time or percent correct answers, but there are differences in both
for specialty and level of experience. There were also differences between the four groups of participants with respect to
what they focus on in a radiology report and how they read reports (skim versus read in detail). There may not be a “one-size-fits-all”
radiology report format as individual preferences differ widely. 相似文献
66.
67.
Response assessment of stereotactic body radiation therapy using dynamic contrast‐enhanced integrated MR‐PET in non‐small cell lung cancer patients
下载免费PDF全文
![点击此处可从《Journal of magnetic resonance imaging : JMRI》网站下载免费的PDF全文](/ch/ext_images/free.gif)
68.
69.
OBJECTIVES: To investigate the relationship of specific nutrients and food items with oral precancerous lesions among tobacco users.
DESIGN: A population-based case-control study. SETTING: Villages in Palitana taluk of Bhavnagar district, Gujarat, India.
SUBJECTS AND METHODS: An interviewer-administered food frequency questionnaire, developed and validated for this population, was used to estimate nutrient intake in blinded, house-to-house interviews. Among 5018 male tobacco users, 318 were diagnosed as cases. An equal number of controls matched on age (±5 years), sex, village, and use of tobacco were selected.
MAIN OUTCOME MEASURES: Odds ratios (OR) from multiple logistic regression analysis controlling for relevant variables (type of tobacco use and economic status).
RESULTS: A protective effect of fibre was observed for both oral submucous fibrosis (OSF) and leukoplakia, with 10% reduction in risk per g day-1 ( P < 0.05). Ascorbic acid appeared to be protective against leukoplakia with the halving of risk in the two highest quartiles of intake (versus the lowest quartile: OR = 0.46 and 0.44, respectively; P < 0.10). A protective effect of tomato consumption was observed in leukoplakia and a suggestion of a protective effect of wheat in OSF.
CONCLUSION: In addition to tobacco use, intake of specific nutrients may have a role in the development of oral precancerous lesions. 相似文献
DESIGN: A population-based case-control study. SETTING: Villages in Palitana taluk of Bhavnagar district, Gujarat, India.
SUBJECTS AND METHODS: An interviewer-administered food frequency questionnaire, developed and validated for this population, was used to estimate nutrient intake in blinded, house-to-house interviews. Among 5018 male tobacco users, 318 were diagnosed as cases. An equal number of controls matched on age (±5 years), sex, village, and use of tobacco were selected.
MAIN OUTCOME MEASURES: Odds ratios (OR) from multiple logistic regression analysis controlling for relevant variables (type of tobacco use and economic status).
RESULTS: A protective effect of fibre was observed for both oral submucous fibrosis (OSF) and leukoplakia, with 10% reduction in risk per g day
CONCLUSION: In addition to tobacco use, intake of specific nutrients may have a role in the development of oral precancerous lesions. 相似文献
70.
树突状细胞与肝脏疾病 总被引:9,自引:3,他引:6
免疫反应的产生首先是由抗原提呈细胞(antigenpresenting cells,APC)捕获抗原,经其加工处理后将抗原信息传递给T,B淋巴细胞,从而引发一系列的特异性免疫应答.APC包括树突状细胞(dendritic cells,DC)、巨噬细胞(MΦ)、B细胞等,其中DC是人体内最具潜能的抗原提呈细胞(APC),能在体内外直接激活纯真(naive)T细胞,提呈抗原给MHC-Ⅰ类限制性CD8+和MHC-Ⅱ类限制性CD4+T淋巴细胞,诱导特异性免疫应答[1-6]. 相似文献