全文获取类型
收费全文 | 7319篇 |
免费 | 716篇 |
国内免费 | 91篇 |
专业分类
耳鼻咽喉 | 44篇 |
儿科学 | 119篇 |
妇产科学 | 88篇 |
基础医学 | 1134篇 |
口腔科学 | 89篇 |
临床医学 | 689篇 |
内科学 | 513篇 |
皮肤病学 | 78篇 |
神经病学 | 752篇 |
特种医学 | 119篇 |
外科学 | 361篇 |
综合类 | 1813篇 |
一般理论 | 1篇 |
预防医学 | 1237篇 |
眼科学 | 60篇 |
药学 | 546篇 |
43篇 | |
中国医学 | 233篇 |
肿瘤学 | 207篇 |
出版年
2024年 | 30篇 |
2023年 | 96篇 |
2022年 | 296篇 |
2021年 | 352篇 |
2020年 | 351篇 |
2019年 | 218篇 |
2018年 | 232篇 |
2017年 | 257篇 |
2016年 | 280篇 |
2015年 | 295篇 |
2014年 | 575篇 |
2013年 | 712篇 |
2012年 | 451篇 |
2011年 | 544篇 |
2010年 | 435篇 |
2009年 | 384篇 |
2008年 | 462篇 |
2007年 | 405篇 |
2006年 | 359篇 |
2005年 | 266篇 |
2004年 | 189篇 |
2003年 | 186篇 |
2002年 | 125篇 |
2001年 | 93篇 |
2000年 | 100篇 |
1999年 | 66篇 |
1998年 | 47篇 |
1997年 | 36篇 |
1996年 | 26篇 |
1995年 | 25篇 |
1994年 | 18篇 |
1993年 | 21篇 |
1992年 | 19篇 |
1991年 | 14篇 |
1990年 | 16篇 |
1989年 | 12篇 |
1988年 | 21篇 |
1987年 | 18篇 |
1986年 | 7篇 |
1985年 | 12篇 |
1984年 | 18篇 |
1983年 | 6篇 |
1982年 | 15篇 |
1981年 | 3篇 |
1980年 | 8篇 |
1979年 | 8篇 |
1978年 | 6篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1975年 | 3篇 |
排序方式: 共有8126条查询结果,搜索用时 15 毫秒
81.
Internet网上细胞凋亡研究的信息资源及其利用 总被引:1,自引:0,他引:1
0 引言 Internet网上含有丰富的信息资源 ,科研人员可以通过 Internet网了解其所研究领域的最新发展动态 ,获取全面和系统的科研信息 ,有利于进行学术交流[1 ] .然而网上信息浩如烟海 ,当检索某一专门领域的资料时 ,有时无从下手 .我们在科研实践中对 Internet网上主要的细胞凋亡研究信息资源及其查找方法进行了归纳 .1 细胞凋亡专业网站1. 1 The Cell death society (http:/ / www.celldeath-apoptosis.org) 为美国细胞死亡学会主办 ,概括了细胞凋亡和程序性细胞死亡研究的各个领域 ,包括与细胞凋亡有关的各种疾病 .可以免费注册… 相似文献
82.
A method is described for investigating life course influences on health in early old age. The lives of some 300 individuals at present aged 65-75 y have been reconstructed from the archived records of a pre-WWII survey, in which they took part as children, and from lifegrid interviews with the same individuals 60 y later. Despite loss to study at several points those interviewed are shown to be representative of the British population socio-demographically, in comparison with the 1931 and 1991 decennial censuses, and physically, in comparison with the Health Survey for England. Bias is conservative because the most disadvantaged were disproportionately affected by loss to follow-up through death and because non-responders to interview were more disadvantaged as children than the interviewees. Representativeness and conservative bias, it is argued, justify the use of these data for investigating life course influences on health in early old age. 相似文献
83.
眶上神经的走行层次及其临床意义 总被引:1,自引:0,他引:1
目的探讨眉区和额部不同手术层面眶上神经的保护方法。方法在15例成人头部标本上,对眶上神经在眉区和额部的行程、走行层次和入肌点的位置进行解剖观测。结果眶上神经出眶上孔后,以52.8±7.4°角向外上经额肌筋膜附着处入帽状腱膜下隙,达发际附近穿帽状腱膜和额肌至皮下。眶上神经起始部直径1.4±0.3mm,本干入肌点至眶上孔的直线距离为40.2±9.1mm,水平距离和垂直距离分别为30.5±8.8mm和33.8±8.4mm。结论根据手术层面的不同,额眉区的深层面手术应注意保护眶上神经 相似文献
84.
P. Wunderbaldinger W. Schima K. Turetschek T. H. Helbich A. A. Bankier C. J. Herold 《European radiology》1999,9(6):1170-1182
Global exchange of information is one of the major sources of scientific progress in medicine. For management of the rapidly
growing body of medical information, computers and their applications have become an indispensable scientific tool. Approximately
36 million computer users are part of a worldwide network called the Internet or “information highway” and have created a
new infrastructure to promote rapid and efficient access to medical, and thus also to radiological, information. With the
establishment of the World Wide Web (WWW) by a consortium of computer users who used a standardized, nonproprietary syntax
termed HyperText Markup Language (HTML) for composing documents, it has become possible to provide interactive multimedia
presentations to a wide audience. The extensive use of images in radiology makes education, worldwide consultation (review)
and scientific presentation via the Internet a major beneficiary of this technical development. This is possible, since both
information (text) as well as medical images can be transported via the Internet. Presently, the Internet offers an extensive
database for radiologists. Since many radiologists and physicians have to be considered “Internet novices” and, hence, cannot
yet avail themselves of the broad spectrum of the Internet, the aim of this article is to present a general introduction to
the WWW/Internet and its applications for radiologists. All Internet sites mentioned in this article can be found at the following
Internet address: http://www.univie.ac.at/radio/radio.html (Department of Radiology, University of Vienna)
Received: 2 February 1998; Revision received: 11 June 1998; Accepted: 27 July 1998 相似文献
85.
Franz M Lieberz K Schmitz N Schepank H 《Social psychiatry and psychiatric epidemiology》1999,34(12):651-656
Background: Our epidemiological study demonstrates the spontaneous long-term course of predominantly psychosocially influenced (“psychogenic”)
disorders (neurotic spectrum disorders, personality disorders, stress reactions and somatoform disorders) in a representative
community sample of the normal adult population of Mannheim, an industrial and university town in Germany. The natural spontaneous
course of these disorders in a population sample over a long period remains largely unknown. Method: Beginning in 1979 (n
t1 = 600) a random population sample was investigated three times over a mean period of approximately 11 years. The last follow-up
study ended in 1994 (n
t3 = 301). The follow-up sample was representative of the t1 sample. Psychodynamically trained and clinically experienced interviewers
used a semi-structured interview and standardized clinical and psychometric instruments. Psychogenic impairment was assessed
using a standardized expert rating (Impairment Score, IS). Results: The mean sum-score of psychogenic impairment after 11 years exceeded the value at t1. The case rate (point prevalence, ICD
diagnosis + clinical cut-off/IS) increased from 21.6% at t1 to 26.2% at t3 in the investigated follow-up sample. Intra-individual
correlation of psychogenic impairment between t1 and t3 was high (r = 0.55). We found strong evidence for an unfavorable long-term course of psychogenic impairment and only a weak tendency
(23.1%) for spontaneous remission of clinically relevant psychogenic impairment. Within a regression model clinical variables,
childhood development conditions and personality traits at t1 predicted psychogenic impairment at t3. Conclusion: All clinical variables conclusively indicate an unfavorable spontaneous long-term course of psychogenic impairment. Together
with the well-known high prevalence of psychogenic disorders in the normal population, this underlines the need for early
therapeutic and preventive intervention.
Accepted: 20 August 1999 相似文献
86.
Spallek H Spallek G 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》1999,96(11):741-748
Hintergrund: Das Medium Internet ist nicht hierarchisch strukturiert und unterscheidet sich daher von herk?mmlichen Wissensquellen. Die
ansteigende Zahl medizinisch-wissenschaftlicher Webseiten bietet dem Augenarzt umfangreiche, jedoch nicht immer leicht zu
erschlie?ende Informations- und Weiterbildungsm?glichkeiten.
Material und Methode: Die Effektivit?t einer Internet-Recherche h?ngt vom Wissenstand über vorhandene Suchstrategien ab. Es werden Suchsysteme
(Search engines, Kataloge, Datenbanken, Indizes) dargestellt sowie Hinweise für deren effektive Nutzung (Metasearch, Anwendung
von Boolean-Operatoren, Wortgruppen-Suche) gegeben. Die Effizienz der Suche wird anhand konkreter Ergebnisse, deren Aktualit?t
und der Anwenderfreundlichkeit der verwendeten Systeme bewertet. Neue, zukunftsweisende Applikationen wie SemioMap und Intelligent
Agents werden vorgestellt.
Ergebnisse und Schlu?folgerung: Bei Anwendung effektiver Suchstrategien stellt das Internet bereits heutzutage eine einfache und schnell zu nutzende Informationsquelle
für den Arzt und Wissenschaftler dar. Die verfügbaren medizinisch-wissenschaftlichen Ressourcen leisten zunehmend aktuelle
und praxisbezogene Beitr?ge zu fachspezifischer Weiterbildung und zukunftsorientierter Forschung.
相似文献
87.
Application of Akaike's information criterion (AIC) in the evaluation of linear pharmacokinetic equations 总被引:13,自引:0,他引:13
Kiyoshi Yamaoka Terumichi Nakagawa Toyozo Uno 《Journal of pharmacokinetics and pharmacodynamics》1978,6(2):165-175
According to linear pharmacokinetics, the time course of plasma concentration of a drug, Cp,is expressed by a sum of exponential functions, Cp=
i=1
n
ai
.This article describes a statistical technique to estimate the number of exponential terms, n,for the time course of drug by the application of Akaike's information criterion (AIC). Plasma concentrations of ethoxybenzamide, sulfisoxazole, bishydroxycoumarin, and diazepam measured following bolus intravenous injection were used as clinical examples for this method. Selection of models is compared between the AIC method and an Ftest method at significance levels of 5% and 1%. 相似文献
88.
The American managed care movement has been viewed as a big experiment and is being watched closely by the rest of the world. In the meanwhile, computer-based information technology (IT) is changing the practice of medicine, much more rapidly than managed care. A New World of digitized knowledge and information has been created. Although literature on IT in psychiatry is largely absent in peer-reviewed psychiatric journals, IT is finding its way into all aspects of medicine, particularly psychiatry. Telepsychiatry programs are becoming very popular. At the same time, medical information sites are flourishing and evolving into a new health-care industry. Patient-physician information asymmetry is decreasing as patients are gaining easy access to medical information hitherto only available to professionals. Thus, psychiatry is facing another paradigm shift, at a time when most attention has been focused on managed care. In this new digital world, knowledge and information are no longer the sole property of professionals. Value will migrate from traditional in-person office-based therapy to digital clinical products, from in-person library search and classroom didactic instruction to interactive on-line searches and distance learning. In this time of value migration, psychiatrists have to determine what their 'distinctive competence' is and where best to add value in the health-care delivery value chain. The authors assess the impact of IT on clinical psychiatry and review how clinical practice, education and research in psychiatry are expected to change in this emerging digital world. 相似文献
89.
目的 :评价前程加速超分割治疗食管癌放疗疗效及放射反应。方法 :对 96例食管癌随机分为前程加速超分割组 (前超组 )和常规组 ,每组 4 8例 ,全部经病理证实。男性 6 3例 ,女性 33例 ;年龄 4 1岁~ 70岁 ,中位年龄 5 7岁 ;病变部位胸上段 2 1例 ,胸中段 6 3例 ,胸下段 12例。病变长度 :<5cm 2 9例 ,5 0cm~ 7 0cm 5 7例 ,>10cm 10例。全部采用 6MVX线外照射 ,常规组 1次 /天 ,2 0Gy/次 ,5次 /周 ,总剂量 6 4Gy~ 6 8Gy ,4 4~ 4 5天完成。前超组 2次 /天 ,1 5Gy/次 ,间隔 6小时以上 ,总剂量 6 4~ 6 8Gy ,35~ 37天完成。 结果 :随访率 96 9%。 1、3、5年生存率前超组为 81 15 %、4 4 1%和 2 6 8% ,常规组为6 1 7%、2 5 1%和 16 9%。前超组 1、3年生存率高于常规组 (u值为 2 97及 2 6 4 ,P <0 0 1) ,5年生存率无显著意义 (u =1 71,P >0 0 5 )。前超组和常规组放射性食管炎发生率分别为 2 7 16和 16 7% (χ2 =1 5 2 ,P =0 2 0 ) ;放射性气管炎发生率前超组为 18 8% ,常规组为 12 5 % (χ2 =0 71,P =0 4 0 )。结论 :食管癌前程加速超分割治疗的 1年和 3年生存率高于常规组 ,5年生存率无明显差异 ,患者对前超组放疗副作用与常规组相比无明显增加。 相似文献
90.
目的评价后程加速超分割放疗加高剂量率后装近距离治疗联合化疗治疗N2、N3期鼻咽癌的近期疗效及毒副反应.方法将80例N2、N3期鼻咽癌随机分为后程加速超分割放疗加高剂量率后装近距离治疗联合化疗组(综合组)和单纯放疗组(常规组).综合组于放疗前先行诱导化疗1次;化疗后先行常规分割照射至鼻咽部剂量为40GY,缩野后改用加速超分割照射至鼻咽部剂量为67GY,体外照射结束后加用高剂量率后装腔内治疗1~2次;于后装治疗结束后再行辅助化疗2次.常规组放疗采用常规分割,鼻咽部总剂量为70GY.结果综合组和常规组鼻咽肿瘤完全消退率分别为92.5%和75%,颈部转移淋巴结控制率为85%和55%(P<0.05),CT扫描检查鼻咽肿瘤完全消退率为72.5%和47.5%(P<0.05).综合组消化道血液毒性大于常规组,但可耐受.结论后程加速超分割放疗加高剂量率后装近距离治疗联合化疗治疗N2、N3期鼻咽癌可提高鼻咽癌的局部控制率,毒副反应可以耐受. 相似文献