全文获取类型
收费全文 | 3584篇 |
免费 | 441篇 |
国内免费 | 88篇 |
专业分类
耳鼻咽喉 | 31篇 |
儿科学 | 72篇 |
妇产科学 | 5篇 |
基础医学 | 480篇 |
口腔科学 | 45篇 |
临床医学 | 256篇 |
内科学 | 375篇 |
皮肤病学 | 4篇 |
神经病学 | 1523篇 |
特种医学 | 226篇 |
外科学 | 114篇 |
综合类 | 179篇 |
预防医学 | 452篇 |
眼科学 | 133篇 |
药学 | 118篇 |
中国医学 | 43篇 |
肿瘤学 | 57篇 |
出版年
2024年 | 16篇 |
2023年 | 58篇 |
2022年 | 112篇 |
2021年 | 160篇 |
2020年 | 149篇 |
2019年 | 137篇 |
2018年 | 128篇 |
2017年 | 150篇 |
2016年 | 142篇 |
2015年 | 150篇 |
2014年 | 219篇 |
2013年 | 301篇 |
2012年 | 184篇 |
2011年 | 190篇 |
2010年 | 163篇 |
2009年 | 167篇 |
2008年 | 184篇 |
2007年 | 174篇 |
2006年 | 178篇 |
2005年 | 132篇 |
2004年 | 156篇 |
2003年 | 103篇 |
2002年 | 96篇 |
2001年 | 75篇 |
2000年 | 42篇 |
1999年 | 35篇 |
1998年 | 48篇 |
1997年 | 53篇 |
1996年 | 35篇 |
1995年 | 31篇 |
1994年 | 27篇 |
1993年 | 28篇 |
1992年 | 27篇 |
1991年 | 14篇 |
1990年 | 21篇 |
1989年 | 17篇 |
1988年 | 16篇 |
1987年 | 20篇 |
1986年 | 7篇 |
1985年 | 35篇 |
1984年 | 26篇 |
1983年 | 19篇 |
1982年 | 19篇 |
1981年 | 16篇 |
1980年 | 17篇 |
1979年 | 8篇 |
1978年 | 16篇 |
1977年 | 6篇 |
1976年 | 4篇 |
1975年 | 2篇 |
排序方式: 共有4113条查询结果,搜索用时 15 毫秒
1.
利用空间频域成像技术搭建的成像系统检测多种皮肤病组织的光学参数和生理参数信息,并对比分析讨论不同类型的皮肤病与光学参数、生理参数之间的关系。实验结果表明,病变皮肤组织与正常皮肤组织之间在光学参数、生理参数上存在较大差异,这将为临床医生对皮肤病诊治提供一种新颖、可靠、科学的评估方法。 相似文献
2.
3.
Health care expenditure in Germany shows clear regional differences. Such geographic variations are often seen as an indicator for inefficiency. With its homogeneous health care system, low co‐payments and uniform prices, Germany is a particularly suited example to analyse regional variations. We use data for the year 2011 on expenditure, utilization of health services and state of health in Germany's statutory health insurance system. This data, which originate from a variety of administrative sources and cover about 90% of the population, are enriched with a wealth of socio‐economic variables, data on pollutants, prices and individual preferences. State of health and demography explains 55% of the differences as measured by the standard deviation while all control variables account for a total of 72% of the differences at county level. With other measures of variation, we can account for an even greater proportion. A higher proportion of variation than usually supposed can thus be explained. Whilst this study cannot quantify inefficiencies, our results contradict the thesis that regional variations reflect inefficiency. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
4.
T. L. Naneishvili M. G. Dashniani G. I. Machavariani 《Neuroscience and behavioral physiology》1987,17(1):49-55
Several types of neurons were differentiated on the basis of a study of neuronal activity in various parts of the cortex near the sulcus principalis during the execution of spatial delayed reactions by monkeys. It was established that the different types of neurons are represented in different numbers in. different parts of the cortex near the sulcus principalis. The determination of several factors influencing the activity of these neurons and the comparison of data on their quantitative representation in the anterior, middle, and posterior parts of the cortex near the sulcus principalis with the existing behavioral data obtained after local ablations of identical regions of the brain made it possible to postulate that neurons belonging to the different types are involved in the analysis of different processes and represent different functional units.Translated from Fiziologicheskii. Zhurnal SSSR imeni I. M. Sechenova, Vol. 71, No. 12, pp. 1488–1494, December, 1985. 相似文献
5.
The recovery of the ability to read of a patient affected by persistent visuospatial neglect suggests the functional independence of the two phenomena. Neglect dyslexia seems to be an example of a dissociation between an implicit and explicit knowledge of the characteristics of the stimulus.
Sommario Il recupero della capacità di lettura in un paziente con persistente neglect visuo-spaziale suggerisce l'indipendenza funzionale dei due fenomeni. La neglect dyslexia sembra costituire un esempio di dissociazione tra conoscenza implicita ed esplicita delle caratteristiche dello stimolo.相似文献
6.
W. N. Charman 《Ophthalmic & physiological optics》2006,26(1):5-12
In the Cardiff acuity test, simple pictures on an otherwise neutral grey card are defined by borders consisting of a relatively broad white band flanked by black bands each half the width of the white band. Higher levels of acuity correspond to the ability to detect figures defined by narrower borders, the figure size remaining constant. It is sometimes implied that the acuity limit corresponding to each card can be equated with different levels of grating resolution, the total width of the border corresponding to the overall grating period. It is shown that although the spatial frequency spectra of the Cardiff figures, like those of other vanishing optotypes, lack very low-frequency components, they have a complex two-dimensional form. The figures have wide spatial bandwidth and no well-defined discrete frequency components. As a result, the relationship between measured Cardiff and grating acuity will vary somewhat, depending upon the particular optical, neural or other deficits of the individual being tested. 相似文献
7.
In our recent review of action control deficits in hemispatial neglect we concluded that many patients with the disorder have deficits in visuomotor control [Coulthard, E., Parton, A., & Husain, M. (2006). Action control in visual neglect. Neuropsychologia, 44(13), 2717-2733]. This conclusion has been questioned and it has been argued instead that there are no action deficits in neglect [Himmelbach, M., Karnath, H.-O., & Perenin, M.-T. (2007). Action control is not affected by spatial neglect: A comment on Coulthard et al. Neuropsychologia, 45(8), 1979-1981]. We proposed that rather than being specific to the neglect syndrome, action control deficits are more likely to relate to lesion location. Although many of these impairments may contribute to the manifestation of neglect, they may also occur in brain-damaged patients without the condition. In this article, we explore this framework further, discussing how neglect behaviour may emerge from damage to a set of visuomotor or cognitive modules, or their connections. Central to our view is the idea that the critical combination of deficits leading to neglect varies considerably between cases, and that visuomotor or cognitive modules disrupted in the syndrome may not, in fact, be specific to neglect. 相似文献
8.
RASER: a new ultrafast magnetic resonance imaging method. 总被引:1,自引:0,他引:1
Ryan Chamberlain Jang-Yeon Park Curt Corum Essa Yacoub Kamil Ugurbil Clifford R Jack Michael Garwood 《Magnetic resonance in medicine》2007,58(4):794-799
A new MRI method is described to acquire a T(2)-weighted image from a single slice in a single shot. The technique is based on rapid acquisition by sequential excitation and refocusing (RASER). RASER avoids relaxation-related blurring because the magnetization is sequentially refocused in a manner that effectively creates a series of spin echoes with a constant echo time. RASER uses the quadratic phase produced by a frequency-swept chirp pulse to time-encode one dimension of the image. In another implementation the pulse can be used to excite multiple slices with phase-encoding and frequency-encoding in the other two dimensions. The RASER imaging sequence is presented along with single-shot and multislice images, and is compared to conventional spin-echo and echo-planar imaging sequences. A theoretical and empirical analysis of the spatial resolution is presented, and factors in choosing the spatial resolution for different applications are discussed. RASER produces high-quality single-shot images that are expected to be advantageous for a wide range of applications. 相似文献
9.
Veronica Amdi 《Early child development and care》1990,58(1):31-43
Every child despite his individual differences and uniqueness is to be considered of equal worth. He should therefore be entitled to equal social, economic, civil and political rights, so that he may fully realise his inherent potential and share equally in life (Gill, 1979).
Obviously, these values are rooted in the humanistic philosophy of any nation's declaration of independence. In accordance with these value premises therefore “any act of commission or ommission by individuals, institutions or the society as a whole, and any conditions which deprive children of equal rights and liberties and interfere with their optimal development, constitutes by definition abuse or neglectful acts or conditions” (Gill, 1979).
Child abuse is a significant contemporary community problem. Although children have been maltreated throughout history, our community has been silent in defence of abused children. Child abuse is not a phenomenon of the 20th Century nor is it unique to our society and culture alone. It has occurred throughout the recorded history of man. The future of any nation depends on its children and their capabilities. For this reason, they must be given a full chance. 相似文献
Obviously, these values are rooted in the humanistic philosophy of any nation's declaration of independence. In accordance with these value premises therefore “any act of commission or ommission by individuals, institutions or the society as a whole, and any conditions which deprive children of equal rights and liberties and interfere with their optimal development, constitutes by definition abuse or neglectful acts or conditions” (Gill, 1979).
Child abuse is a significant contemporary community problem. Although children have been maltreated throughout history, our community has been silent in defence of abused children. Child abuse is not a phenomenon of the 20th Century nor is it unique to our society and culture alone. It has occurred throughout the recorded history of man. The future of any nation depends on its children and their capabilities. For this reason, they must be given a full chance. 相似文献
10.
The mistreatment of elderly is subject to various social constructions. On two geographically distinct Plains Indian Reservations which we call Lone Mountain and Abundant Lands, the abuse or neglect of elderly is construed as a health problem which is a dysfunction of the community as a whole. Both physical abuse and neglect are more common on the Lone Mountain Reservation, occurring in association with other indicators of community disorganization such as unemployment and substance abuse. On the Abundant Lands Reservation physical abuse was categorically denied and what neglect existed appeared to be a function of role strain, geographic dispersal, climate and terrain. We attribute differences in the prevalence of mistreatment of elders to variations in economic opportunities for younger residents. Examining the historical and present contexts of intergenerational relationships on the reservations, we discuss the implications of this study for social exchange theory and policy applications.This research was supported by the Gerontological Society of America AppliedThis research was supported by the Gerontological Society of America AppliedThis research was supported by the Gerontological Society of America AppliedThis research was supported by the Gerontological Society of America AppliedThis research was supported by the Gerontological Society of America AppliedThis research was supported by the Gerontological Society of America Applied 相似文献