全文获取类型
收费全文 | 1498篇 |
免费 | 119篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 117篇 |
妇产科学 | 106篇 |
基础医学 | 161篇 |
口腔科学 | 60篇 |
临床医学 | 132篇 |
内科学 | 287篇 |
皮肤病学 | 72篇 |
神经病学 | 65篇 |
特种医学 | 75篇 |
外科学 | 170篇 |
综合类 | 37篇 |
预防医学 | 99篇 |
眼科学 | 41篇 |
药学 | 77篇 |
中国医学 | 18篇 |
肿瘤学 | 105篇 |
出版年
2023年 | 29篇 |
2022年 | 18篇 |
2021年 | 40篇 |
2020年 | 34篇 |
2019年 | 43篇 |
2018年 | 46篇 |
2017年 | 41篇 |
2016年 | 37篇 |
2015年 | 48篇 |
2014年 | 70篇 |
2013年 | 104篇 |
2012年 | 92篇 |
2011年 | 74篇 |
2010年 | 74篇 |
2009年 | 60篇 |
2008年 | 76篇 |
2007年 | 72篇 |
2006年 | 99篇 |
2005年 | 81篇 |
2004年 | 71篇 |
2003年 | 60篇 |
2002年 | 61篇 |
2001年 | 21篇 |
2000年 | 16篇 |
1999年 | 24篇 |
1998年 | 15篇 |
1997年 | 8篇 |
1996年 | 11篇 |
1995年 | 9篇 |
1994年 | 6篇 |
1993年 | 8篇 |
1992年 | 10篇 |
1991年 | 15篇 |
1990年 | 6篇 |
1989年 | 8篇 |
1988年 | 7篇 |
1987年 | 4篇 |
1986年 | 6篇 |
1985年 | 4篇 |
1983年 | 4篇 |
1979年 | 6篇 |
1975年 | 7篇 |
1974年 | 14篇 |
1973年 | 7篇 |
1972年 | 6篇 |
1971年 | 10篇 |
1969年 | 5篇 |
1968年 | 5篇 |
1967年 | 4篇 |
1923年 | 3篇 |
排序方式: 共有1626条查询结果,搜索用时 0 毫秒
61.
62.
Nicholas S. Phillips Yin Ting Cheung John O. Glass Matthew A. Scoggins Wei Liu Robert J. Ogg Daniel A. Mulrooney Ching‐Hon Pui Leslie L. Robison Wilburn E. Reddick Melissa M. Hudson Kevin R. Krull 《Pediatric blood & cancer》2020,67(3)
Survivors of childhood acute lymphoblastic leukemia (ALL) treated with chemotherapy only are at risk for neurocognitive impairment. Regions of interest were identified a priori based on glucocorticoid receptor distribution, and sex‐stratified multivariable linear regression models were used to test associations between brain MRI morphology and total number of intrathecal injections, and serum concentration of dexamethasone and methotrexate. Compared with controls, ALL survivors have persistently smaller volumes in the bilateral cerebellum (P < 0.005), hippocampal subregions (P < 0.03), temporal lobe regions (P < 0.03), frontal lobe regions (P < 0.04), and parietal lobe regions (precuneus; P < 0.002). Long‐term problems with learning may be related to residual posttreatment brain differences. 相似文献
63.
Aleks Stolicyn Mathew A. Harris Xueyi Shen Miruna C. Barbu Mark J. Adams Emma L. Hawkins Laura de Nooij Hon Wah Yeung Alison D. Murray Stephen M. Lawrie J. Douglas Steele Andrew M. McIntosh Heather C. Whalley 《Human brain mapping》2020,41(14):3922-3937
Major depressive disorder (MDD) has been the subject of many neuroimaging case–control classification studies. Although some studies report accuracies ≥80%, most have investigated relatively small samples of clinically‐ascertained, currently symptomatic cases, and did not attempt replication in larger samples. We here first aimed to replicate previously reported classification accuracies in a small, well‐phenotyped community‐based group of current MDD cases with clinical interview‐based diagnoses (from STratifying Resilience and Depression Longitudinally cohort, ‘STRADL’). We performed a set of exploratory predictive classification analyses with measures related to brain morphometry and white matter integrity. We applied three classifier types—SVM, penalised logistic regression or decision tree—either with or without optimisation, and with or without feature selection. We then determined whether similar accuracies could be replicated in a larger independent population‐based sample with self‐reported current depression (UK Biobank cohort). Additional analyses extended to lifetime MDD diagnoses—remitted MDD in STRADL, and lifetime‐experienced MDD in UK Biobank. The highest cross‐validation accuracy (75%) was achieved in the initial current MDD sample with a decision tree classifier and cortical surface area features. The most frequently selected decision tree split variables included surface areas of bilateral caudal anterior cingulate, left lingual gyrus, left superior frontal, right precentral and paracentral regions. High accuracy was not achieved in the larger samples with self‐reported current depression (53.73%), with remitted MDD (57.48%), or with lifetime‐experienced MDD (52.68–60.29%). Our results indicate that high predictive classification accuracies may not immediately translate to larger samples with broader criteria for depression, and may not be robust across different classification approaches. 相似文献
64.
Wei Chang Colin Tan Sanjna Nilesh Nerurkar Hai Yun Cai Harry Ho Man Ng Duoduo Wu Yu Ting Felicia Wee Jeffrey Chun Tatt Lim Joe Yeong Tony Kiat Hon Lim 《癌症》2021,40(9):367-387
常规免疫组织化学(immunohistochemistry,IHC)是组织病理学中广泛应用的诊断技术.但该技术存在诸多局限性,包括观察者间的变异性高,每张组织切片仅能标记一个标志物.本文详细描述了各种多重检测技术,这些技术克服了上述局限性,可在单张切片上同时检测多个标志物,可对细胞组成、细胞功能和细胞间相互作用进行整合... 相似文献
65.
Swine as a principal reservoir of hepatitis E virus that infects humans in eastern China 总被引:19,自引:0,他引:19
Zheng Y Ge S Zhang J Guo Q Ng MH Wang F Xia N Jiang Q 《The Journal of infectious diseases》2006,193(12):1643-1649
BACKGROUND AND METHODS: Genotype IV hepatitis E virus (HEV) has been isolated from humans and swine. To study the relationship between the human and swine reservoirs, we estimated their respective viral burden, analyzed the genetic makeup of the virus populations, and assessed the risk of infection associated with swine farming. RESULTS: In 2 swine-farming districts of eastern China, 9.6% of swine and 0.3% of healthy human subjects excreted HEV in stool, as did 68.8% of patients with confirmed HEV infection. The virus population circulating in humans consisted of genotype I and at least 4 phylogenetically distinct subgroups of genotype IV viruses, 2 of which concurrently circulated among swine. Persons engaged in occupations related to swine farming were found to have a 74% higher risk of infection than those engaged in other occupations, and persons living in communities downstream of the swine farms were found to have a 29% higher risk of infection than persons living in communities upstream. CONCLUSIONS: Genotype IV HEV is freely transmitted between humans and swine. Because the size of the swine population and its viral burden are much larger than those of humans, transmission of the virus most likely is directed from swine to humans. Infection can be acquired through contact with swine and their waste. 相似文献
66.
67.
Kam-Lun Ellis Hon Ka-Wah Tony Lee Kam-Lau Cheung Pak-Cheung Ng 《Acta paediatrica (Oslo, Norway : 1992)》2009,98(8):1363-1365
Snakebites in children and teenagers are relatively uncommon in the metropolitan city of Hong Kong. They are rarely fatal but may cause significant morbidity and fear. We report two cases of snakebites to illustrate that the spectrum of morbidity is independent of the size of the snakes. A 7-year-old boy was bitten in successions by a green snake. Envenomation occurred at the second bite site. He developed local and systemic signs that were promptly relieved with anti-venom therapy at the intensive care unit. An 18-year-old girl was bitten by a large python but only sustained minor local soft tissue injuries. This report serves to alert the public that snake may bite in successions and envenomation may occur with the subsequent bite.
Conclusion: A small snake may be venomous and a large snake may not be. Avoidable risk factors associated with snakebites (such as avoiding areas known to harbour snakes in the evening in summer and autumn and wearing protective footwear) are highlighted. 相似文献
Conclusion: A small snake may be venomous and a large snake may not be. Avoidable risk factors associated with snakebites (such as avoiding areas known to harbour snakes in the evening in summer and autumn and wearing protective footwear) are highlighted. 相似文献
68.
69.
70.