全文获取类型
收费全文 | 49234篇 |
免费 | 2834篇 |
国内免费 | 183篇 |
专业分类
耳鼻咽喉 | 635篇 |
儿科学 | 1231篇 |
妇产科学 | 1124篇 |
基础医学 | 6802篇 |
口腔科学 | 2916篇 |
临床医学 | 4090篇 |
内科学 | 10844篇 |
皮肤病学 | 1304篇 |
神经病学 | 4573篇 |
特种医学 | 1137篇 |
外国民族医学 | 1篇 |
外科学 | 5520篇 |
综合类 | 290篇 |
一般理论 | 13篇 |
预防医学 | 4706篇 |
眼科学 | 991篇 |
药学 | 3618篇 |
中国医学 | 321篇 |
肿瘤学 | 2135篇 |
出版年
2023年 | 377篇 |
2022年 | 515篇 |
2021年 | 1704篇 |
2020年 | 966篇 |
2019年 | 1504篇 |
2018年 | 1814篇 |
2017年 | 1218篇 |
2016年 | 1318篇 |
2015年 | 1522篇 |
2014年 | 2016篇 |
2013年 | 2595篇 |
2012年 | 3914篇 |
2011年 | 4147篇 |
2010年 | 2163篇 |
2009年 | 1746篇 |
2008年 | 3064篇 |
2007年 | 3053篇 |
2006年 | 2743篇 |
2005年 | 2552篇 |
2004年 | 2433篇 |
2003年 | 2055篇 |
2002年 | 1920篇 |
2001年 | 943篇 |
2000年 | 943篇 |
1999年 | 755篇 |
1998年 | 299篇 |
1997年 | 212篇 |
1996年 | 217篇 |
1995年 | 159篇 |
1994年 | 144篇 |
1993年 | 115篇 |
1992年 | 292篇 |
1991年 | 284篇 |
1990年 | 264篇 |
1989年 | 202篇 |
1988年 | 199篇 |
1987年 | 190篇 |
1986年 | 165篇 |
1985年 | 148篇 |
1984年 | 144篇 |
1983年 | 117篇 |
1982年 | 69篇 |
1981年 | 83篇 |
1980年 | 69篇 |
1979年 | 93篇 |
1978年 | 70篇 |
1975年 | 56篇 |
1971年 | 60篇 |
1969年 | 48篇 |
1967年 | 67篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
33.
34.
Rosario Fernández-Plata Rogelio Pérez-Padilla Rodrigo Del Río-Hidalgo Cecilia García-Sancho Laura Gochicoa-Rangel Christian Rodríguez-Hernández Luis Torre-Bouscoulet David Martínez-Briseño 《Archivos de bronconeumología》2019,55(10):513-518
IntroductionPeople with Down syndrome (DS) have high respiratory morbidity, evaluating their respiratory health with standardized, objective tests is desirable. Thus, the objective of this study was to evaluate the technical quality of Pulmonary Function Tests (PFTs) to determine which ones are most suitable for this population.MethodsParticipants included children, teenagers and adults with DS, 5 years of age or older (n = 302). The technical quality of the impulse oscillometry system (IOS), forced spirometry, lung-diffusing capacity for carbon monoxide (DLCO), and 6-min walk test (6MWT) were analyzed by age group. Capnography and pulse oximetry were included in the study. Technical quality was determined on the basis of current international PFTs standards.ResultsFifty-one percent of participants were males. A total of 184 participants (71%) who completed the IOS fulfilled the quality criteria, while 210 (70%) completed the 6MWT. Performance on forced spirometry and DLCO was poor. All pulse oximetries and 96% percent heart rates obtained had good quality, but exhaled carbon dioxide (PetCO2) and respiratory rate (RR) showed deficient repeatability.ConclusionsIOS appears to be the most reliable instrument for evaluating lung mechanics in individuals with DS. 相似文献
35.
36.
37.
38.
Mehmet Varol Kadriye Benkli Ayşe T. Koparal Rakibe B. Bostancıoğlu 《Drug and chemical toxicology》2019,42(4):436-443
Drug design and discovery studies are important because of the prevalence of diseases without available medical cures. New anticancer agents are particularly urgent because of the high mortality rate associated with cancer. A series of mononuclear gold (III) and platinum (II) complexes based on boronated phenylalanine (BPA) were designed and synthesized using 4,4’-dimethyl-2,2’-dipyridyl (L1) or 1,10-phenanthroline-5,6-dion (L2) ligands to obtain promising anticancer drug candidates. Proton nuclear magnetic resonance, infrared, mass spectrometry, and elemental analyses were utilized for chemical characterizations. Cell viability, cancer cell colony formation, endothelial tube formation, and cytoskeleton staining assays were performed using A549 lung adenocarcinoma and human umbilical vein endothelial cells (HUVECs) to investigate preliminary pharmacological activities. L1-based platinum (II) complex (BPA-L1-Pt) was the most promising complex, and has similar activity with the approved chemotherapy drug cis-platinum. Half maximal inhibitory concentration values for BPA-L1-Pt were 9.15 µM on A549s and 16.61 µM on HUVECs; the values for cis-platinum were 5.24 µM on A549s and 23.14 µM on HUVECs. Consequently, further synthesis studies should be performed to boost the cancer cell selectivity feature of BPA by varying metal and ligand types. 相似文献
39.