全文获取类型
收费全文 | 5771篇 |
免费 | 474篇 |
国内免费 | 36篇 |
专业分类
耳鼻咽喉 | 464篇 |
儿科学 | 145篇 |
妇产科学 | 50篇 |
基础医学 | 878篇 |
口腔科学 | 175篇 |
临床医学 | 668篇 |
内科学 | 468篇 |
皮肤病学 | 35篇 |
神经病学 | 1391篇 |
特种医学 | 88篇 |
外科学 | 238篇 |
综合类 | 126篇 |
一般理论 | 1篇 |
预防医学 | 734篇 |
眼科学 | 556篇 |
药学 | 163篇 |
1篇 | |
中国医学 | 12篇 |
肿瘤学 | 88篇 |
出版年
2024年 | 23篇 |
2023年 | 99篇 |
2022年 | 177篇 |
2021年 | 279篇 |
2020年 | 202篇 |
2019年 | 247篇 |
2018年 | 224篇 |
2017年 | 246篇 |
2016年 | 236篇 |
2015年 | 210篇 |
2014年 | 300篇 |
2013年 | 608篇 |
2012年 | 281篇 |
2011年 | 339篇 |
2010年 | 263篇 |
2009年 | 300篇 |
2008年 | 319篇 |
2007年 | 285篇 |
2006年 | 252篇 |
2005年 | 205篇 |
2004年 | 145篇 |
2003年 | 146篇 |
2002年 | 116篇 |
2001年 | 90篇 |
2000年 | 83篇 |
1999年 | 69篇 |
1998年 | 59篇 |
1997年 | 49篇 |
1996年 | 55篇 |
1995年 | 36篇 |
1994年 | 29篇 |
1993年 | 21篇 |
1992年 | 23篇 |
1991年 | 25篇 |
1990年 | 23篇 |
1989年 | 19篇 |
1988年 | 16篇 |
1987年 | 17篇 |
1986年 | 18篇 |
1985年 | 34篇 |
1984年 | 19篇 |
1983年 | 11篇 |
1982年 | 12篇 |
1981年 | 9篇 |
1980年 | 11篇 |
1979年 | 10篇 |
1978年 | 6篇 |
1977年 | 11篇 |
1975年 | 5篇 |
1970年 | 4篇 |
排序方式: 共有6281条查询结果,搜索用时 46 毫秒
41.
Event-related potentials (ERPs) were recorded in male and female participants in response to 32 male and 32 female faces. Participants were instructed to simply look carefully at each face; after ERP collection they were asked to rate each face on a 5-point attractiveness scale. A positive correlation between average rating and average P300 scores to opposite sex faces was observed in male (r = .40) and in preovulatory (r = .41) and postovulatory (r = .44) female subjects. Correlations to same sex faces were only found in postovulatory females (r = .61). Male participants showed a much larger average P300 than did female participants, and the P300 evoked in female participants was unexpectedly larger to female than to male faces. Neither task relevance nor stimulus probability is a plausible explanations for these findings because they were experimentally controlled. These results support the emotional value hypothesis, according to which classical P300 processes reflect an affective evaluation of the stimulus, which in turn produces context updating. 相似文献
42.
Röder B Spence C Rösler F 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2002,143(4):453-462
If a peripheral target follows an ipsilateral cue with a stimulus-onset-asynchrony (SOA) of 300 ms or more, its detection is delayed compared to a contralateral-cue condition. This phenomena, known as inhibition-of-return (IOR), affects responses to visual, auditory, and tactile stimuli, and is thought to provide an index of exogenous shifts of spatial attention. The present study investigated whether tactile IOR occurs in a somatotopic vs an allocentric frame of reference. In experiment 1, tactile cue and target stimuli were presented to the index and middle fingers of either hand, with the hands positioned in an uncrossed posture (SOA 500 or 1,000 ms). Speeded target detection responses were slowest for targets presented from the cued finger, and were also slower for targets presented to the adjacent finger on the cued hand than to either finger on the uncued hand. The same pattern of results was also reported when the index and middle fingers of the two hands were interleaved on the midline (experiment 2), suggesting that the gradient of tactile IOR surrounding a cued body site is modulated by the somatotopic rather than by the allocentric distance between cue and target. 相似文献
43.
Hemispheric Prevalence Changes in Partial Epileptic Patients on Perceptual and Attentional Tasks 总被引:4,自引:3,他引:1
In relation to the general issue of the long-term effects of epileptic activity on the higher nervous functions, monohemispheric epileptic patients--divided into "lesional" [i.e., with computed tomography (CT) scan-visible lesions] and "nonlesional" (i.e., with CT scan-nonvisible lesions)--were submitted to dichotic verbal and tonal tasks, dichoptic verbal and spatial tasks, and a visual tachistoscopic attentional task. The aim was to investigate whether the typical patterns of hemispheric prevalence, which were observed in normal subjects by using these tests, undergo significant changes in epileptic patients. The findings versus normal subjects seem to demonstrate that (a) in lesional epileptic patients, the prevalence of the hemisphere without macroscopic lesions is a constant rule, whether or not this hemisphere is prevalent in normal subjects; (b) in nonlesional epileptic patients, the patterns are the following: when the epileptic hemisphere is the one that is prevalent in normal subjects, its prevalence is enhanced, whichever the hemisphere; when the epileptic hemisphere is not the hemisphere prevalent in normal subjects, the left one attracts and maintains prevalence, whereas the right one reduces and variously interferes with contralateral prevalence. It is concluded that, with respect to the functions tested, the nature of the epileptic foci seems to influence markedly the interhemispheric prevalence pattern. 相似文献
44.
Paula Francekovi Lucía García-Torralba Eleni Sakoulogeorga Tea Vu
kovi Federico J. A. Perez-Cueto 《Nutrients》2021,13(4)
The meat production industry is one of the leading contributors of greenhouse gas emissions. Cultured meat presents itself as a potential eco- and animal-friendly meat substitute which has the potential to eradicate animal cruelty and reduce both the environmental footprint and the risk of zoonotic illnesses, while delivering a nutrient-dense product. The purpose of this study was to investigate how consumers perceive cultured meat and if the frequency of meat consumption is related to their intention of trying or purchasing cultured meat. Data were collected online in 2020 from Croatia, Greece, and Spain. Among the 2007 respondents, three segments were identified according to meat consumption and variety, plus an a priori identified group of “non-meat eaters”. Sixty percent perceived cultured meat as kind to animals, 57% as unnatural, 45% as healthy and environmentally-friendly, 21% as disgusting, and only 16% as tasty. Although 47% of the respondents had not heard of cultured meat before, 47% would taste it and 41% would purchase it for the same price as conventional meat. This indicates that consumers from Croatia, Greece and Spain might be likely to purchase cultured meat if sold at an affordable price. 相似文献
45.
目的探讨同伴教育在乳腺癌患者中的应用效果。方法选择2019年1月至2021年6月广东药科大学附属第一医院收治的64例乳腺癌患者作为研究对象,按随机数字表法将其分为两组,每组各32例。对照组开展常规健康宣教,观察组在此基础上实施同伴教育,两组均持续干预3个月,比较两组疾病感知、创伤后成长及生命质量。结果观察组干预后疾病感知评分低于对照组,创伤后成长评分、生命质量评分均高于对照组,差异有统计学意义(P<0.05)。结论同伴教育能够降低乳腺癌患者的负性疾病感知,有利于创伤后成长,进而提高生命质量。 相似文献
46.
Mattias Delpont Manon Racicot Andr Durivage Lucie Fornili Jean‐Luc Guerin Jean‐Pierre Vaillancourt Mathilde C. Paul 《Transboundary and Emerging Diseases》2021,68(1):51-61
Biosecurity is crucial for infectious disease prevention, more importantly in the absence of vaccination. The need for improving the implementation of biosecurity practices was highlighted in French duck farms following the 2016–2017 H5N8 Highly Pathogenic Avian Influenza (HPAI) epidemic. Farmers have multiple reasons for not implementing biosecurity practices: external (time, money) and internal (socio‐psychological). The purpose of this study was to determine how sets of socio‐psychological factors (i.e. knowledge on biosecurity and avian influenza transmission, attitudes, personality traits, social background) affect the adoption of on‐farm biosecurity practices. Biosecurity practices and socio‐psychological determinants were assessed during 127 duck farm visits, in South West France, using both questionnaires and on‐farm observations. Factorial analysis of mixed data (FAMD) and hierarchical clustering analysis (HCA) identified three groups of farmers with different socio‐psychological profiles: the first group was characterized by minimal knowledge, negative attitudes towards biosecurity, little social pressure and a low level of conscientiousness. The second group was characterized by more extensive experience in poultry production, higher stress and social pressure. The third group was characterized by less experience in poultry production, better knowledge and positive attitudes towards biosecurity, increased self‐confidence and orientation towards action. The first group had a significantly lower adoption of biosecurity measures than the two other groups. A better understanding of the factors involved in farmers' decision‐making could improve the efficiency of interventions aiming at improving and maintaining the level of on‐farm biosecurity in the duck industry. 相似文献
47.
48.
多通道人工耳蜗在语前聋儿童及青少年中的应用 总被引:4,自引:0,他引:4
目的 通过对植入人工耳蜗的语前聋儿童和青少年的听力和语言能力的评估 ,探讨我国儿童在使用人工耳蜗后的听力和言语能力发展规律及影响因素。方法 2 5例行人工耳蜗植入的语前聋儿童及青少年患者参与本组测试。选用《聋儿听觉言语康复评估方法》作为测试材料 ,分别进行声音、言语声和环境声的辨别 ,数词、单字词、双字词、3字词、韵母、声母、声调、封闭项列短句的识别 ,开放项列字词和开放项列短句识别 ,语言清晰度 ,模仿句长 ,听话识图和看图说话等方面测试。结果 受试者术后均能感知到声音 ,辨别不同类别的声音。封闭项列测试结果全部大于机会水平 ,正确识别率随人工耳蜗使用时间而不断增加 ,随植入时年龄的增长而呈下降趋势。术后约半年显现开放项列识别能力 ,使用人工耳蜗后对患儿的言语发育具有较大帮助。结论 尽早对语前聋患儿植入人工耳蜗及进行术后康复 ,以达改善听力 ,提高语言能力 ,促进身心全面发展的目的。 相似文献
49.
Gregory McCarthy Mark Spicer Anthony Adrignolo Marie Luby John Gore Truett Allison 《Human brain mapping》1994,2(4):234-243
Localized brain activation in response to moving visual stimuli was studied by functional magnetic resonance imaging (fMRI). Stimuli were 100 small white dots randomly arranged on a visual display. During the Motion condition, the dots moved along random, noncoherent linear trajectories at different velocities. During the Blink condition, the dots remained stationary but blinked on and off every 500 ms. The Motion and Blink conditions continuously alternated with 10 cycles per run and 6–8 runs per experiment. In half of the runs, the starting stimulus condition was Motion, while in the remaining runs it was Blink. A series of 128 gradient echo echoplanar images were acquired from 5–7 slices during each run using a 1.5 T GE Signa with an Advanced NMR echoplanar subsystem. The time series for each voxel were analyzed in the frequency domain. Voxels which demonstrated a significant spectral peak at the alternation frequency and whose phase changed in response to stimulus order were considered activated. These activated voxels were displayed upon high resolution anatomical images to determine the sites of activation and were also transformed into the coordinates of Talairach and Tournoux ([1988] Co-planar Stereotaxic Atlas of the Human Brain, New York: Thieme) for comparison to prior neuroimaging studies. Seven of ten subjects showed clusters of activation bilaterally at the junction of the temporal and occipital lobes (area 37) in response to moving stimuli. Most activated voxels were located within or adjacent to a region designated the parietal-temporal-occipital fossa, or PTOF. Five subjects also showed activation to moving stimuli in midline occipital cortex. The activated voxels in midline cortex had a significantly shorter phase delay in their MR signal change relative to voxels in PTOF. © 1995 Wiley-Liss, Inc. 1 1 This article is a US Government work and, as such, is in the public domain in the United States of America 相似文献
50.
为了解分泌性中耳炎( O M E)对内耳听觉功能的影响,对 O M E220 例、304 耳分别进行纯音测听及声阻抗测定。结果表明,部分 O M E 患者骨导听阈升高,除造成传音性耳聋外,合并感音性耳聋( S N H L)为318% ,并随着病程延长, S N H L 发病率增高。提示应积极有效地治疗本病,应用扩血管及营养神经药物可防治 S N H L的发生。 相似文献