全文获取类型
收费全文 | 1083212篇 |
免费 | 72360篇 |
国内免费 | 1380篇 |
专业分类
耳鼻咽喉 | 15069篇 |
儿科学 | 34813篇 |
妇产科学 | 28777篇 |
基础医学 | 154487篇 |
口腔科学 | 29752篇 |
临床医学 | 95880篇 |
内科学 | 205042篇 |
皮肤病学 | 24557篇 |
神经病学 | 82374篇 |
特种医学 | 43264篇 |
外国民族医学 | 201篇 |
外科学 | 164346篇 |
综合类 | 21933篇 |
现状与发展 | 1篇 |
一般理论 | 269篇 |
预防医学 | 75493篇 |
眼科学 | 24729篇 |
药学 | 86780篇 |
7篇 | |
中国医学 | 2815篇 |
肿瘤学 | 66363篇 |
出版年
2019年 | 7902篇 |
2018年 | 11457篇 |
2017年 | 9041篇 |
2016年 | 10207篇 |
2015年 | 11407篇 |
2014年 | 15452篇 |
2013年 | 22503篇 |
2012年 | 31044篇 |
2011年 | 32772篇 |
2010年 | 19179篇 |
2009年 | 18045篇 |
2008年 | 30365篇 |
2007年 | 32521篇 |
2006年 | 33201篇 |
2005年 | 31473篇 |
2004年 | 30146篇 |
2003年 | 28925篇 |
2002年 | 27875篇 |
2001年 | 60209篇 |
2000年 | 61651篇 |
1999年 | 51102篇 |
1998年 | 12550篇 |
1997年 | 11094篇 |
1996年 | 11085篇 |
1995年 | 10377篇 |
1994年 | 9406篇 |
1993年 | 8928篇 |
1992年 | 37933篇 |
1991年 | 36408篇 |
1990年 | 35851篇 |
1989年 | 34405篇 |
1988年 | 30971篇 |
1987年 | 30110篇 |
1986年 | 28328篇 |
1985年 | 26569篇 |
1984年 | 19275篇 |
1983年 | 16205篇 |
1982年 | 8880篇 |
1979年 | 17106篇 |
1978年 | 11460篇 |
1977年 | 10289篇 |
1976年 | 8876篇 |
1975年 | 10119篇 |
1974年 | 11716篇 |
1973年 | 11317篇 |
1972年 | 10794篇 |
1971年 | 10128篇 |
1970年 | 9293篇 |
1969年 | 8983篇 |
1968年 | 7952篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
G. N. Smith Jr E. A. Mickler K. K. Payne J. Lee M. Duncan J. Reynolds B. Foresman D. S. Wilkes 《American journal of transplantation》2007,7(7):1856-1861
Parenchymal disease in the allograft lung is associated with interstitial remodeling believed to be mediated by matrix metalloproteinases (MMPs). Recent studies suggest high levels of MMP-9 are associated with bronchiolitis obliterans syndrome (BOS) in lung transplant recipients. Since BOS occurs late in the posttransplant period and may be preceded by episodes of acute rejection or infection, which are associated with interstitial remodeling, we examined MMP profiles in allograft bronchoalveolar lavage (BAL) fluid in the early posttransplant period (preceding BOS). Gelatin zymography, protein array analysis and specific ELISA on BAL fluids from transplanted lungs indicated that MMP-8, MMP-9 and TIMP-1 were strongly expressed in allograft BAL fluid from stable patients, or those with infection or rejection compared to BAL fluid from normal volunteers. Elevated expression of MMP-8, MMP-9 and TIMP-1 occurred early, and was sustained for the 3.2 years covered in this study. Elevations of MMP-8, MMP-9 and TIMP-1 in the first 2 years posttransplant appear to be associated with lung transplantation itself, and not infection or rejection. These data suggest that ongoing and clinically silent MMP activity could perpetuate progressive disease in the allograft lung. 相似文献
992.
Nienhaus A. Kromark K. Raulf-Heimsoth M. van Kampen V. Merget R. 《Trauma und Berufskrankheit》2007,10(1):75-77
Trauma und Berufskrankheit - Die Vermeidung gepuderter Latexhandschuhe gilt als wichtige Maßnahme zur Prävention von latexbedingten Haut- und Atemwegsallergien bei Beschäftigten im... 相似文献
993.
Prof. Dr. K. Hartung H. Ehrfeld A. Gerritzen J.G. Kuipers B. Wolters 《Zeitschrift für Rheumatologie》2007,66(5):395-416
This third part of this series of articles on laboratory diagnostics of rheumatic diseases considers the rheumatic diseases caused by infection by microorganisms, or reactive arthritides. The basis for laboratory diagnostics of infection-reactive arthritides is the investigation of anti-infection antibodies. In some situations, DNA amplification methods may be helpful. Bacterially infected joints should be immediately examined by arthrocentesis and microscopic examination and laboratory culture of the synovial fluid. 相似文献
994.
Z D Daniil E Zintzaras T Kiropoulos A I Papaioannou A Koutsokera A Kastanis K I Gourgoulianis 《The European respiratory journal》2007,30(5):957-964
Pleural effusion is a common complication of various diseases. Conventional methods are not always capable of establishing the cause of pleural effusion, so alternative tests are needed. The aim of this study was to explore means of discriminating between different pleural effusion groups, malignant, parapneumonic and tuberculous, based on the combined function of seven biological markers. Adenosine deaminase (ADA), interferon-gamma, C-reactive protein (CRP), carcinoembryonic antigen, interleukin-6, tumour necrosis factor-alpha and vascular endothelial growth factor concentration levels were measured in pleural fluid from 45 patients with malignant, 15 with parapneumonic and 12 with tuberculous pleural effusion. Receiver operating characteristic curve analysis, multinomial logit modelling and canonical variate analysis were applied to discriminate the pleural effusion groups. The three groups could be discriminated successfully using the measured markers. The most important parameters for discrimination were ADA and CRP concentration levels. An individual with an ADA concentration level of >45 U.L(-1) and a CRP concentration of <4 mg.dL(-1) was more likely to belong to the tuberculous pleural effusion group, whereas one with an ADA concentration level of <40 U.L(-1) and a CRP concentration of >6 mg.dL(-1) was more likely to belong to the parapneumonic pleural effusion group, and one with a CRP concentration of <4 mg.dL(-1) to the malignant pleural effusion group. The combination of adenosine deaminase and C-reactive protein levels might be sufficient for discriminating between the three different groups of exudative pleural effusion: malignant, tuberculous and parapneumonic. 相似文献
995.
K Knapczyk M Duda D Czaplicki M Slomczynska 《Experimental and clinical endocrinology & diabetes》2007,115(7):411-416
Steroid hormones play an essential role in the ovarian cyclicity control and the progress of pregnancy. One of the crucial enzymes in the steroidogenesis is 3beta-hydroxysteroid dehydrogenase/Delta5-Delta4 isomerase (3betaHSD). The aim of the present study was to localize both 3betaHSD mRNA and protein in the ovary of pregnant swine. The immunolocalization of 3betaHSD was performed on paraplast sections of follicles and corpora lutea obtained on various days of gestation: 10, 18, 32, 50, 71 and 90 POST COITUM (p.c.). The obtained results were compared with those concerning follicular and luteal development in the ovaries of the cycling pig. Differences in 3betaHSD distribution between the ovarian follicles of cycling and pregnant pigs were concerned mainly in the pattern of immunostaining of the theca interna cells. In the porcine ovaries obtained on various days of pregnancy, some follicles exhibited positive immunostaining in most theca interna cells, while in other follicles this enzyme was expressed only in a relatively small percentage of theca interna cells. In the corpora lutea of the estrous cycle and pregnancy changes in the pattern of immunostaining were observed. At early and mid pregnancy (up to 71 day p.c.) 3betaHSD was observed in the large luteal cells while on day 71 p.c. the enzyme was present exclusively in the small luteal cells. The expression of 3betaHSD mRNA was detected by the use of RT-PCR technique in all investigated samples isolated at different stages of pregnancy. 相似文献
996.
K. K. Würzler M. Heisterkamp H. Böhm N. R. Kübler W. Sebald und J. F. Reuther 《Mund-, Kiefer- und Gesichtschirurgie》2004,8(2):75-82
ZusammenfassungFragestellung In der vorliegenden Studie am Göttinger Minischwein wurde die direkte Rekonstruktion des Unterkiefers nach ausgedehnter Kontinuitätsresektion mit autologem Knochen und einem osteoinduktiven Implantat untersucht.Methode An neun ausgewachsenen Göttinger Minischweinen wurde ein einseitiger, 5 cm langer Unterkieferkontinuitätsdefekt gesetzt. Die Rekonstruktion erfolgte bei vier Tieren mit einem 50×25×15 mm3 großen, kollagenen Träger, dotiert mit rhBMP-2 (400 µg/cm3). Bei zwei Tieren wurde nur der Träger alleine implantiert und bei drei Tieren das lokal resezierte Knochensegment replantiert. Die Knochenregeneration und Konsolidierung der Defekte wurde radiologisch und histologisch analysiert.Ergebnisse Nach Rekonstruktion mit dem osteoinduktiven Implantat zeigte sich bei allen Versuchstieren eine komplette knöcherne Konsolidierung des gesetzten Unterkieferkontinuitätsdefekts. Der gesamte Defekt wurde von einem biomechanisch hochwertigen, sich funktionell anpassenden Knochen überbrückt. Nach Replantation des ortsständigen autologen Knochens wird dieser nicht schnell genug knöchern integriert. In der Peripherie bilden sich nur unvollständige Knochenbrücken aus; dies führt zum vollständigen Versagen der Rekonstruktion. Ebenso findet bei der Implantation des Trägers alleine keine Konsolidierung statt.Schlussfolgerung Die direkte Rekonstruktion eines ausgedehnten, biomechanisch belasteten Defekts mit einem osteoinduktiven Implantat erwies sich als die überlegene Methode. Das hierbei entstehende knöcherne Regenerat erfährt eine unmittelbare funktionelle Strukturierung. Die Notwendigkeit zu extensiven adaptiven Umbauvorgängen wird hierdurch minimiert. 相似文献
997.
The aim of this article is to provide clinicians and researchers a comprehensive overview of the development and functions of gesture in childhood and in select populations with developmental language impairments. Of significance is the growing body of evidence that gesture enhances, not hinders, language development. In both normal and impaired populations, gesture and language development parallel each other and share underlying symbolic abilities. Gesture serves several functions, including those of communication, compensation, and transition to spoken language. In clinical practice, gesture may play a valuable role in diagnosis, prognosis, goal selection, and intervention for children with language impairments. Where available, supporting evidence is presented. Needs for additional research on gesture are also highlighted. 相似文献
998.
K. Bahlke T. Scholbach T. Rhein F. Deckert A. Tannapfel J. Hauss Prof. Dr. H. Witzigmann 《Gef?sschirurgie》2004,9(3):215-219
The celiac axis compression syndrome is a rare disease in adults. In childhood it is extremely uncommon. Vascular reasons or chronic irritation of the celiac ganglion are discussed as causes for this syndrome, leading to chronic abdominal pain. Lateral aortography is acknowledged to be the best method for diagnosis of the celiac axis compression syndrome. New duplex scanning methods are gaining more and more importance. The indication for surgery is the subject of controversy in the current literature. We present the case of a 15-year-old girl who recovered completely after transsection of the ligamentum arcuatum medianum and resection of the celiac ganglion. 相似文献
999.
1000.
After a comprehensive rernew of the literature on syphilitic
aortitis, Longcope, (1) stated in 1913; ": . . . the presence of spiro:
chetes in these lesions, as might be expected, cannot by any means be
constantly demonstrated with Levaaiti stain. . . . . . . That these
organisms are ''Treponema pallidum seems almost certain thouS:h actual
proof of such by culture from the arterial lesions, a most difficult task,
or direct inoculation into animals, has not as yet been accomplished." 相似文献