全文获取类型
收费全文 | 18298篇 |
免费 | 2055篇 |
国内免费 | 1121篇 |
专业分类
耳鼻咽喉 | 140篇 |
儿科学 | 403篇 |
妇产科学 | 303篇 |
基础医学 | 4182篇 |
口腔科学 | 431篇 |
临床医学 | 1564篇 |
内科学 | 3595篇 |
皮肤病学 | 397篇 |
神经病学 | 965篇 |
特种医学 | 401篇 |
外国民族医学 | 12篇 |
外科学 | 1434篇 |
综合类 | 2760篇 |
现状与发展 | 5篇 |
预防医学 | 864篇 |
眼科学 | 267篇 |
药学 | 1402篇 |
2篇 | |
中国医学 | 181篇 |
肿瘤学 | 2166篇 |
出版年
2024年 | 46篇 |
2023年 | 421篇 |
2022年 | 729篇 |
2021年 | 1259篇 |
2020年 | 848篇 |
2019年 | 815篇 |
2018年 | 693篇 |
2017年 | 642篇 |
2016年 | 673篇 |
2015年 | 832篇 |
2014年 | 1106篇 |
2013年 | 1109篇 |
2012年 | 1137篇 |
2011年 | 1305篇 |
2010年 | 1102篇 |
2009年 | 1129篇 |
2008年 | 1078篇 |
2007年 | 1011篇 |
2006年 | 875篇 |
2005年 | 707篇 |
2004年 | 505篇 |
2003年 | 383篇 |
2002年 | 290篇 |
2001年 | 310篇 |
2000年 | 267篇 |
1999年 | 246篇 |
1998年 | 229篇 |
1997年 | 197篇 |
1996年 | 151篇 |
1995年 | 147篇 |
1994年 | 151篇 |
1993年 | 125篇 |
1992年 | 109篇 |
1991年 | 69篇 |
1990年 | 71篇 |
1989年 | 67篇 |
1988年 | 67篇 |
1987年 | 47篇 |
1986年 | 44篇 |
1985年 | 77篇 |
1984年 | 54篇 |
1983年 | 44篇 |
1982年 | 36篇 |
1981年 | 47篇 |
1980年 | 54篇 |
1979年 | 28篇 |
1978年 | 35篇 |
1977年 | 19篇 |
1976年 | 29篇 |
1975年 | 15篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
目的:探索以系统化、标准化的新型冠状病毒核酸检测为核心和重要组成部分,建立适合于眼科医院新冠疫情精准防控切实可行的防控体系。方法:系列病例研究。自2020年2月24日至3月2日期间,以标准化病毒核酸检测联合血常规、C反应蛋白(CRP)、血清淀粉样蛋白A(SAA)等检测作为所有眼科手术患者术前筛查常规检测项目,同时也为返岗员工提供病毒核酸检测。设计调查问卷了解受检者对鼻咽拭子采样的接受度以及核酸检测结果对其心理状态的影响。结果:99例患者血液学检测结果有一定的异常比例,其中SAA检测结果增高13例,淋巴细胞计数减低12例、增高5例,白细胞计数增高11例、减低1例,CRP增高2例,新型冠状病毒核酸检测均阴性。33例本院职工新型冠状病毒核酸检测均阴性。12%的受访者对鼻咽拭子采样接受度评分较低。受检者在核酸检测前后思想压力评分较高的比例分别为46.7%和6.7%。结论:该项举措一方面为术前新冠病毒肺炎筛查及鉴别诊断提供了客观依据,很大程度上排除了隐性无症状感染者传播的可能,有利于减少二次传播的风险,降低院内交叉感染的概率;另一方面,核酸检测阴性结果有利于调整患者术前的心理状态并缓解医护人员在疫情防控期间的心理压力。 相似文献
4.
5.
《Diagnostic and interventional imaging》2020,101(9):555-564
PurposeThe purpose of this study was to determine whether computed tomography (CT)-based machine learning of radiomics features could help distinguish autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma (PDAC).Materials and MethodsEighty-nine patients with AIP (65 men, 24 women; mean age, 59.7 ± 13.9 [SD] years; range: 21–83 years) and 93 patients with PDAC (68 men, 25 women; mean age, 60.1 ± 12.3 [SD] years; range: 36–86 years) were retrospectively included. All patients had dedicated dual-phase pancreatic protocol CT between 2004 and 2018. Thin-slice images (0.75/0.5 mm thickness/increment) were compared with thick-slices images (3 or 5 mm thickness/increment). Pancreatic regions involved by PDAC or AIP (areas of enlargement, altered enhancement, effacement of pancreatic duct) as well as uninvolved parenchyma were segmented as three-dimensional volumes. Four hundred and thirty-one radiomics features were extracted and a random forest was used to distinguish AIP from PDAC. CT data of 60 AIP and 60 PDAC patients were used for training and those of 29 AIP and 33 PDAC independent patients were used for testing.ResultsThe pancreas was diffusely involved in 37 (37/89; 41.6%) patients with AIP and not diffusely in 52 (52/89; 58.4%) patients. Using machine learning, 95.2% (59/62; 95% confidence interval [CI]: 89.8–100%), 83.9% (52:67; 95% CI: 74.7–93.0%) and 77.4% (48/62; 95% CI: 67.0–87.8%) of the 62 test patients were correctly classified as either having PDAC or AIP with thin-slice venous phase, thin-slice arterial phase, and thick-slice venous phase CT, respectively. Three of the 29 patients with AIP (3/29; 10.3%) were incorrectly classified as having PDAC but all 33 patients with PDAC (33/33; 100%) were correctly classified with thin-slice venous phase with 89.7% sensitivity (26/29; 95% CI: 78.6–100%) and 100% specificity (33/33; 95% CI: 93–100%) for the diagnosis of AIP, 95.2% accuracy (59/62; 95% CI: 89.8–100%) and area under the curve of 0.975 (95% CI: 0.936–1.0).ConclusionsRadiomic features help differentiate AIP from PDAC with an overall accuracy of 95.2%. 相似文献
6.
7.
Jin Wu Hao Wang Qing Li Qian-Ying Guo Si-Qi Tao Yu-Xian Shen Zheng-Sheng Wu 《Pathology, research and practice》2019,215(9):152523
Mammary carcinoma (MC) is one of most common malignancy in women, and ring finger protein 2 (RNF2) possesses various roles in vast human tumors. In MC tissues as well as in cell lines RNF2 exhibited high expression, had significant association with tumor size, lymph node status, TNM stage, patients’ poor survival, and promoted cell proliferation, colony formation, cell migration and invasion of MC cell lines which was mediated by downregulation of E-cadherin protein. These data reveal that RNF2 protein plays a vital role in the development of MC and may be a potential therapy target of MC. 相似文献
8.
Frédéric Janvier Deborah Delaune Thomas Poyot Eric Valade Audrey Mérens Pierre E. Rollin Vincent Foissaud 《Emerging infectious diseases》2016,22(2):292-294
We evaluated RNA stability of Ebola virus in EDTA blood and urine samples collected from infected patients and stored in West Africa’s environmental conditions. In blood, RNA was stable for at least 18 days when initial cycle threshold values were <30, but in urine, RNA degradation occurred more quickly. 相似文献
9.
Although hepatitis E virus (HEV) is the primary cause of enterically transmitted acute hepatitis and jaundice in developing countries, locally acquired HEV infections are increasing in nonendemic countries. As such, HEV is emerging as an underdiagnosed cause of infection. This report describes three clinically variable cases of HEV infection with unusual clinical presentations. These cases highlight the fact that HEV should be considered in the differential diagnosis of patients with unexplained hepatitis (acute or chronic) with or without extrahepatic manifestations. HEV should also be considered in patients with persistently elevated liver enzymes who have not travelled to known HEV-endemic regions. Lack of knowledge among physicians and an absence of standardized diagnostic tests may result in increased morbidity and mortality from HEV infection. 相似文献
10.