全文获取类型
收费全文 | 55492篇 |
免费 | 5026篇 |
国内免费 | 3578篇 |
专业分类
耳鼻咽喉 | 539篇 |
儿科学 | 665篇 |
妇产科学 | 459篇 |
基础医学 | 6460篇 |
口腔科学 | 853篇 |
临床医学 | 6701篇 |
内科学 | 8989篇 |
皮肤病学 | 688篇 |
神经病学 | 3100篇 |
特种医学 | 2526篇 |
外国民族医学 | 19篇 |
外科学 | 5836篇 |
综合类 | 8888篇 |
现状与发展 | 14篇 |
一般理论 | 7篇 |
预防医学 | 3514篇 |
眼科学 | 1368篇 |
药学 | 5898篇 |
52篇 | |
中国医学 | 2845篇 |
肿瘤学 | 4675篇 |
出版年
2024年 | 159篇 |
2023年 | 770篇 |
2022年 | 1977篇 |
2021年 | 2702篇 |
2020年 | 1998篇 |
2019年 | 1777篇 |
2018年 | 1845篇 |
2017年 | 1701篇 |
2016年 | 1826篇 |
2015年 | 2642篇 |
2014年 | 3150篇 |
2013年 | 3118篇 |
2012年 | 4451篇 |
2011年 | 4743篇 |
2010年 | 3416篇 |
2009年 | 2625篇 |
2008年 | 3180篇 |
2007年 | 3185篇 |
2006年 | 2860篇 |
2005年 | 2808篇 |
2004年 | 2042篇 |
2003年 | 2127篇 |
2002年 | 1795篇 |
2001年 | 1317篇 |
2000年 | 1022篇 |
1999年 | 963篇 |
1998年 | 583篇 |
1997年 | 562篇 |
1996年 | 374篇 |
1995年 | 437篇 |
1994年 | 309篇 |
1993年 | 190篇 |
1992年 | 274篇 |
1991年 | 198篇 |
1990年 | 166篇 |
1989年 | 173篇 |
1988年 | 116篇 |
1987年 | 124篇 |
1986年 | 119篇 |
1985年 | 62篇 |
1984年 | 40篇 |
1983年 | 21篇 |
1982年 | 25篇 |
1981年 | 16篇 |
1980年 | 15篇 |
1979年 | 15篇 |
1974年 | 8篇 |
1973年 | 13篇 |
1972年 | 9篇 |
1969年 | 12篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
31.
32.
Anatomic and spiral computed tomographic study of the genial tubercles for genioglossus advancement.
Shan Kai Yin Hong Liang Yi Wen Ying Lu Jian Guan Hong Min Wu Zhen Yu Cao Dong Zhen Yu Yan Yan Huang Chun Gen Wu 《Otolaryngology--head and neck surgery》2007,136(4):632-637
OBJECTIVE: To measure and compare Chinese mandibular genial tubercles measured anatomically and with computed tomography (CT). STUDY DESIGN AND SETTING: Spiral CT scans were taken of 40 adult human skulls; the superior genial spines were measured using anatomic and CT methods. RESULTS: The height and width of the superior genial spines, mandible thickness, and distance from the menton to the inferior and superior margins of the superior genial spines were 5.82 +/- 0.71, 6.98 +/- 1.35, 11.95 +/- 1.59, 11.08 +/- 2.05, and 16.91 +/- 2.30 mm from anatomic measurements and 6.17 +/- 0.71, 7.01 +/- 1.13, 12.19 +/- 1.64, 10.41 +/- 1.55, and 15.73 +/- 2.12 mm using spiral CT, respectively. The anatomic and CT measurements were correlated. CONCLUSION: Spiral CT of the genial tubercles can help locate the osteotomy in genioglossus advancement. SIGNIFICANCE: This study acquired reference data on Chinese genial tubercles demonstrating that CT measurements of the genial tubercles reflect their anatomy, which should allow accurately locate the osteotomy. 相似文献
33.
34.
用不同剂量尿烷一次腹腔注射,对KM、BALB/c和A/J系小鼠进行肺肿瘤短期诱导试验,以比较其敏感性,为环境化学物致癌性鉴定的实验条件提供依据。结果显示:以肺肿瘤发生率和平均发瘤数两项指数来衡量发瘤危险,A/J系均在最低染毒剂量(25mg/kg)即出现发瘤危险明显增高;KM系以发生率衡量时,100mg/kg为发瘤危险增高的最低剂量,而以平均发瘤数衡量时,最低剂量为200mg/kg;BALB/c系前 相似文献
35.
眼内异物合并外伤性白内障是眼外伤常见的致盲原因之一,各地报告的致盲率为20%~48.9%。本文对88例眼内异物合并外伤性白内障患者采用联合手术治疗,收到较好疗效,术前视力0.05以下占85.2%,术后矫正视力0.05以下占27.3%,矫正视力0.06~1.5占73.7%,其中矫正视力0.6~1.5者占22.8%。根据异物的性质、在眼内部位和晶体损伤情况选择不同的手术方式一次联合手术摘出异物和白内障,术后采用中西药配合治疗。联合手术可提高疗效,减少术后并发症.减少手术次数,减轻病人的痛苦,缩短病程,减少医疗费用.眼科学报1993;9:216—218. 相似文献
36.
37.
Peng?Dong Ling?Ling?Wong Sarah?Ng Marie?Loh Adrian?MondryEmail author 《BMC medical informatics and decision making》2004,4(1):21
Background
Critically Appraised Topics (CATs) are a useful tool that helps physicians to make clinical decisions as the healthcare moves towards the practice of Evidence-Based Medicine (EBM). The fast growing World Wide Web has provided a place for physicians to share their appraised topics online, but an increasing amount of time is needed to find a particular topic within such a rich repository.Methods
A web-based application, namely the CAT Crawler, was developed by Singapore's Bioinformatics Institute to allow physicians to adequately access available appraised topics on the Internet. A meta-search engine, as the core component of the application, finds relevant topics following keyword input. The primary objective of the work presented here is to evaluate the quantity and quality of search results obtained from the meta-search engine of the CAT Crawler by comparing them with those obtained from two individual CAT search engines. From the CAT libraries at these two sites, all possible keywords were extracted using a keyword extractor. Of those common to both libraries, ten were randomly chosen for evaluation. All ten were submitted to the two search engines individually, and through the meta-search engine of the CAT Crawler. Search results were evaluated for relevance both by medical amateurs and professionals, and the respective recall and precision were calculated.Results
While achieving an identical recall, the meta-search engine showed a precision of 77.26% (±14.45) compared to the individual search engines' 52.65% (±12.0) (p < 0.001).Conclusion
The results demonstrate the validity of the CAT Crawler meta-search engine approach. The improved precision due to inherent filters underlines the practical usefulness of this tool for clinicians.38.
Butyrate increases production of human chimeric IgG in CHO-K1 cells whilst maintaining function and glycoform profile 总被引:3,自引:0,他引:3
Mimura Y Lund J Church S Dong S Li J Goodall M Jefferis R 《Journal of immunological methods》2001,247(1-2):205-216
The influence of sodium butyrate on the production and glycosylation of recombinant mouse/human chimeric antibody by transfected CHO-K1 cells was investigated. We selected cells expressing 'wild-type' antibody with a human IgG3 heavy chain and a mutant of this molecule in which Phe 243 is replaced by Ala. These proteins have previously been shown to exhibit very different glycoform profiles with the mutant IgG being comprised of glycoforms having a high galactose and sialic acid content. Cell culture with 0-5 mM butyrate was shown to effect a 2-4-fold increase in antibody production whilst the induction of apoptosis was observed in a dose-dependent manner. The optimal butyrate concentration was observed to be 2 mM. The glycoform profile of each antibody produced in the presence of butyrate was analyzed by HPAEC-PAD and shown to be unchanged, relative to that produced in the absence of butyrate. Biological activity was evaluated by the ability of the antibodies to trigger superoxide generation, through Fc gamma RI, and shown to be independent of production in the presence or absence of butyrate. A similar increase in production was observed for a high antibody-producing cell line when expanded in a hollow fibre bioreactor under low-serum conditions (1%). These results demonstrated that butyrate is of value for increasing the productivity of CHO-K1 for recombinant IgG and does not compromise either glycosylation or biological activity. 相似文献
39.
40.
涎腺癌肉瘤临床及病理分析 总被引:6,自引:0,他引:6
目的:探讨涎腺癌肉瘤的临床病理学特点及其鉴别诊断。方法:对3例涎腺癌肉瘤患者的临床资料进行回顾性研究并复习相关文献,对全部病例的组织学标本重新进行镜下观察。结果:涎腺癌肉瘤临床表现常为迅速增大的颜面部肿物并伴疼豢。光匀下组织学观察常可见肉瘤和癌两种成分并存,癌多为鳞状细胞癌和腺癌,肉瘤以骨或软骨肉瘤为主。结论:涎腺癌肉瘤的临床特点与涎腺其他恶性肿瘤较难区别,但涎腺癌肉瘤的恶性程度极高。 相似文献