全文获取类型
收费全文 | 7412篇 |
免费 | 653篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 113篇 |
儿科学 | 276篇 |
妇产科学 | 238篇 |
基础医学 | 1103篇 |
口腔科学 | 216篇 |
临床医学 | 702篇 |
内科学 | 1265篇 |
皮肤病学 | 91篇 |
神经病学 | 507篇 |
特种医学 | 162篇 |
外科学 | 961篇 |
综合类 | 157篇 |
一般理论 | 1篇 |
预防医学 | 1378篇 |
眼科学 | 97篇 |
药学 | 498篇 |
中国医学 | 8篇 |
肿瘤学 | 305篇 |
出版年
2021年 | 67篇 |
2019年 | 77篇 |
2018年 | 115篇 |
2017年 | 71篇 |
2016年 | 79篇 |
2015年 | 97篇 |
2014年 | 162篇 |
2013年 | 186篇 |
2012年 | 262篇 |
2011年 | 285篇 |
2010年 | 155篇 |
2009年 | 163篇 |
2008年 | 254篇 |
2007年 | 289篇 |
2006年 | 253篇 |
2005年 | 248篇 |
2004年 | 236篇 |
2003年 | 198篇 |
2002年 | 221篇 |
2001年 | 247篇 |
2000年 | 261篇 |
1999年 | 183篇 |
1998年 | 133篇 |
1997年 | 139篇 |
1996年 | 151篇 |
1995年 | 190篇 |
1994年 | 93篇 |
1993年 | 96篇 |
1992年 | 204篇 |
1991年 | 213篇 |
1990年 | 183篇 |
1989年 | 133篇 |
1988年 | 145篇 |
1987年 | 148篇 |
1986年 | 131篇 |
1985年 | 140篇 |
1984年 | 136篇 |
1983年 | 106篇 |
1982年 | 98篇 |
1981年 | 85篇 |
1980年 | 88篇 |
1979年 | 133篇 |
1978年 | 94篇 |
1977年 | 92篇 |
1974年 | 86篇 |
1973年 | 87篇 |
1972年 | 84篇 |
1971年 | 90篇 |
1970年 | 98篇 |
1969年 | 80篇 |
排序方式: 共有8078条查询结果,搜索用时 31 毫秒
991.
992.
993.
994.
Samuel S. Shin Matthew J. Tormenti Alessandro Paluzzi William E. Rothfus Yue-Fang Chang Hanady Zainah Juan C. Fernandez-Miranda Carl H. Snyderman Sue M. Challinor Paul A. Gardner 《Pituitary》2013,16(4):435-444
We report the outcomes of the endoscopic endonasal approach (EEA) for resection of growth hormone secreting pituitary adenomas using 2010 consensus criteria. We also assess outcomes with additional medical therapy and radiosurgery (RS) for patients not achieving remission with EEA alone. A retrospective review of 53 patients who had follow up endocrinologic data at least 3 months post-surgery was performed among patients who were treated by EEA between 1998 and 2012. Data were analyzed for remission using GH and IGF-I levels based on 2010 consensus criteria. We also analyzed the outcomes using 2000 consensus criteria for ease in comparison to prior studies of outcomes of surgery for acromegaly. In this series of mostly large (88.2 % macroadenomas), invasive (46.9 % Hardy–Wilson C, D, E) adenomas, there were 27 patients (50.9 %) who achieved remission after EEA only. For patients who had no remission with EEA alone, RS and/or medical therapy were used and 37 patients (69.8 %) achieved remission overall. Statistical analysis showed larger tumor size, Hardy Stages C, D, E and Knosp Scores 3, 4 to be predictive against remission for EEA only and EEA with other modalities. The volume of residual tumor after EEA was not found to be predictive of remission with additional therapies. We used stringent consensus criteria from 2010 in a series which included a high proportion of invasive GH secreting adenomas to show that EEA alone or combined with other modalities results in comparable remission rates to earlier studies which used less strict criteria, while retaining low complication rates. 相似文献
995.
996.
997.
Martin J. Gardner 《Sozial- und Pr?ventivmedizin》1991,36(4-5):276-278
Summary There is occasionally concern about suspected clusters of disease in geographically localised areas among members of the general public or other groups. These occurrences need a systematic approach to their investigation. Such an approach needs to consider the definition and characteristics of the cluster and of the putative environmental cause for concern. Depending on the outcome of these considerations there will be different actions, possibly involving epidemiological studies. The necessary components of the approach and resulting actions are outlined in this paper, and illustrated by the example of childhood leukaemia rates around the Sellafield nuclear plant.
Das Vorgehen bei ungewöhnlichen Krankheitshäufungen (Clusters), dargestellt am Beispiel der Häufung von Kindheitsleukämien von Sellafield
Zusammenfassung Clusters von Krankheitsfällen können in der Bevölkerung grosse Besorgnis verursachen. Wie geht der damit konfrontierte Epidemiologe am besten vor? Es wird ein systematisches Vorgehen in Stufen vorgeschlagen, von der Überprüfung der Diagnosen und der Abgrenzung des Clusters bis zur allfälligen Planung von epidemiologischen Studien. Die einzelnen Schritte werden anhand der Häufung von Kindheitsleukämien im Umfeld von Sellafield dargestellt.
Investigations de «clusters»: Les leucémies infantiles dans la région de Sellafield comme exemple
Résumé Les «clusters» de maladie peuvent être à l'origine d'une préoccupation considérable dans la population. Quelle peut être la réaction la plus appropriée de l'épidémiologue? Une approche systématique est présentée dans cet article, depuis la caractérisation du «cluster» jusqu' à la planification d'études épidémiologiques éventuelles. Chacun de ces pas est illustré par l'exemple concret d'une situation similaire survenue dans la région de Sellafield à propos de l'accroissement des leucémies infantiles autour de l'usine de retraitement de produits nucléaires.相似文献
998.
J A Graham D E Gardner E J Blommer D E House M G Ménache F J Miller 《Journal of toxicology and environmental health》1987,21(1-2):113-125
The nitrogen dioxide (NO2) diurnal cycle found in urban communities usually consists of a low basal concentration upon which are superimposed higher concentration peaks or spikes of short duration. Various components of this environmental exposure mode were examined to assess effects of urban exposure profiles on susceptibility to infectious pulmonary disease. Mice were exposed to NO2 peaks of 4.5 ppm for 1, 3.5, or 7 h, challenged with Streptococcus sp. either immediately or 18 h postexposure, and then observed for mortality. When the streptococcal challenges were immediately after NO2 exposure, the mortality rate was directly related to the length of peak exposure, whether or not a basal exposure was used, and all peak lengths significantly increased mortality. When the challenge was delayed for 18 h after the peak exposure, spiked exposures of 3.5 and 7 h increased mortality to the same degree. If a 1-h peak exposure to 4.5 ppm was superimposed twice daily upon a continuous basal NO2 concentration of 1.5 ppm, there was a suggestive trend toward increased mortality near the end of the second week of exposure when challenge occurred immediately after the morning spike. Studies were also conducted to examine interactions with ozone (O3) and NO2, since urban air typically contains both of these oxidants. Using various combinations of basal and spiked exposure levels of NO2 and O3, synergistic results were obtained for streptococcal-induced mortality. 相似文献
999.
CT-guided transthoracic needle biopsy 总被引:7,自引:0,他引:7
Douglas Gardner Eric vanSonnenberg M.D. Horacio B. D'Agostino Giovanna Casola Steven Taggart Stuart May 《Cardiovascular and interventional radiology》1991,14(1):17-23
CT-guided biopsy of pulmonary and mediastinal lesions is safe and effective. It is most valuable in those cases in which fluoroscopic
guidance is not possible due to resolution or anatomic consideration. CT guidance permits puncture of lesions as small as
0.5 cm, typically not seen fluoroscopically. Sensitivity of biopsy in malignant lung lesions in our series of 83 cases was
92%. Pneumothorax is the most frequent complication (10–60%) and requires chest tube insertion in 5–15% of patients. 相似文献
1000.
The results of experiments in which horseradish peroxidase (HRP)was used to mark single trophectoderm or inner cell mass (ICM)cells in situ in mouse blastocysts have led to the proposalthat growth of the trophectoderm depends on stem cells locatedin the inner cell mass. Thus, the finding that the visual centreof clones formed following labelling of the central polar trophectodermcell in early or expanding blasrtocysts was consistently shiftedtowards or into the mural trophectoderm was attributed to theirdisplacement by ICM-derived cells. However, the frequency withwhich central polar cells were displaced is likely to have beenoverestimated by using the visual centre of descendant clonesas the index of their location. also, the possibility that displacementof central polar cells was an artefact of the marked temporaryinterruption of their cycling that resulted from labelling wasnot discounted. Furthermore, no attempt was made to ascertainwhether cells located elsewhere in the polar trophectoderm alsomoved murally, as expected if there is a general displacementof such cells. In the present study, labelling of either thecentral or a peripheral polar trophectoderm cell with HRP wasachieved without obviously perturbing their subsequent proliferation.Moreover, displacement was assessed by recording the locationof the proximal boundary rather than the visual centre of theresulting clones. Even by this conservative criterion, the majorityof labelled central cells moved towards or into the mural trophectoderm. In marked contrast, however, labelled peripheral polarcells moved murally in only a minority of cases. The remaindereither retained their original position or moved towards ratherthan away from the central polar region. Such an anisotropicpattern of growth of the polar trophec toderm is not readilyexplicable in terms of recruitment of cells from the ICM. Rather,it accords with the view that the polar trophectoderm is a proliferativecentre, and suggests that movement murally of its surplus cellsmay be restricted circuinferentially, possibly through anchorageof the junctional trophectoderm cells that extend processesover the free surface of the ICM. 相似文献