全文获取类型
收费全文 | 264672篇 |
免费 | 24743篇 |
国内免费 | 20586篇 |
专业分类
耳鼻咽喉 | 2026篇 |
儿科学 | 2323篇 |
妇产科学 | 3005篇 |
基础医学 | 32629篇 |
口腔科学 | 4284篇 |
临床医学 | 37902篇 |
内科学 | 38559篇 |
皮肤病学 | 2405篇 |
神经病学 | 14914篇 |
特种医学 | 9565篇 |
外国民族医学 | 198篇 |
外科学 | 25233篇 |
综合类 | 44445篇 |
现状与发展 | 74篇 |
一般理论 | 27篇 |
预防医学 | 15915篇 |
眼科学 | 8243篇 |
药学 | 28258篇 |
304篇 | |
中国医学 | 15994篇 |
肿瘤学 | 23698篇 |
出版年
2024年 | 1409篇 |
2023年 | 4491篇 |
2022年 | 11414篇 |
2021年 | 14111篇 |
2020年 | 10940篇 |
2019年 | 9391篇 |
2018年 | 9730篇 |
2017年 | 8617篇 |
2016年 | 8169篇 |
2015年 | 12206篇 |
2014年 | 14965篇 |
2013年 | 12547篇 |
2012年 | 18784篇 |
2011年 | 21533篇 |
2010年 | 13036篇 |
2009年 | 10058篇 |
2008年 | 13333篇 |
2007年 | 13363篇 |
2006年 | 13595篇 |
2005年 | 13848篇 |
2004年 | 8203篇 |
2003年 | 7603篇 |
2002年 | 6380篇 |
2001年 | 5700篇 |
2000年 | 6424篇 |
1999年 | 7175篇 |
1998年 | 4741篇 |
1997年 | 4758篇 |
1996年 | 3676篇 |
1995年 | 3515篇 |
1994年 | 2900篇 |
1993年 | 1965篇 |
1992年 | 2214篇 |
1991年 | 1842篇 |
1990年 | 1569篇 |
1989年 | 1333篇 |
1988年 | 1134篇 |
1987年 | 992篇 |
1986年 | 749篇 |
1985年 | 608篇 |
1984年 | 349篇 |
1983年 | 214篇 |
1982年 | 115篇 |
1981年 | 127篇 |
1980年 | 83篇 |
1979年 | 90篇 |
1965年 | 1篇 |
1962年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
971.
972.
Polycystic ovary syndrome (PCOS) is associated with low-grade chronic inflammation.This was a retrospective case–control study.In the present study, the risk coefficients of neutrophil to lymphocyte ratio (NLR), high-sensitive C-reactive protein (hs-CRP), and mean platelet volume (MPV) in obese patients with PCOS were determined. This study was designed to investigate NLR, hs-CRP, and MPV levels in 68 obese patients with PCOS and 44 nonobese patients with PCOS, and our study group was matched with 47 obese and 43 nonobese controls, respectively.PCOS group had higher MPV, NLR, insulin, glucose, and HOMA-IR rates than those of the controls. Subgroup analyses revealed that the obese PCOS group had higher NLR, hs-CRP, and MPV levels compared to those of controls. The obese PCOS group had higher NLR, hs-CRP, and MPV levels compared to those of the nonobese PCOS group. The odds ratios and 95% confidence intervals of those variables (NLR, hs-CRP, MPV) were found significant (P < .05). NLR, hs-CRP, and MPV variables were found statistically significant in the analysis of receiver operating characteristics.Our study demonstrated that NLR, hs-CRP, and MPV levels are increased in patients with obese PCOS. 相似文献
973.
Rheumatoid arthritis (RA) is a common chronic autoimmune disease characterized by synovial inflammation and progressive joint destruction. Eucommia ulmoides (EU) is a kidney-tonifying Chinese medicine that has been applied to treat RA for decides. The present study aims to explore pharmacological mechanisms of EU against RA using network pharmacology approach. Traditional Chinese Medicine Systems Pharmacology (TCMSP) database was used to screen active ingredients of EU, and their relative targets were fished from UniProt database. RA-related targets were screened from GeneCards database and DisGeNET database. The overlapping genes between EU and RA were identified by Venn diagram, and further analyzed for protein-protein interaction (PPI), Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG). Fifty active ingredients were identified in EU, and corresponded to 207 targets. Meanwhile, 499 targets were closely associated with RA development. A total of 50 overlapping genes between EU and RA were identified, which were regarded as therapeutically relevant. GO enrichment analysis indicated that EU exerted antiRA effects depending on regulating multiple biological processes including inflammatory response, oxidative stress, cell apoptosis and matrix catabolism. Several key pathways such as TNF pathway, IL-17 pathway, T cell receptor pathway, NOD-like receptor pathway and Toll-like receptor pathway, were involved in the above biological processes. Network pharmacology revealed that EU exerts therapeutic effects on RA through multi-ingredients, multi-targets and multi-pathways, which provides basis for its clinical application and promising directions for subsequent research. 相似文献
974.
975.
Retraction of ‘In situ Raman investigation of the phase transition of NaVO2F2 under variable temperature conditions’ by Sa Zhang et al., RSC Adv., 2021, 11, 23550–23556, https://doi.org/10.1039/D1RA02827H.We, the named authors, hereby wholly retract this RSC Advances article due to issues with the equipment used during the research and the resulting errors due to an unstable temperature control system.A Raman spectrometer was used for the testing outlined in this research, utilising coupled variable temperatures to investigate the phase transition of NaVO2F2. The temperature change was controlled by a THMS600 high and low-temperature sample stand. After the publication of this research, the unstable temperature was found to be caused by the system of the THMS600 sample stage, which lead to the temperature error in the analysis of phase transformation during the heating process. This has led to errors in the analysis, and therefore the conclusions of this paper are not supported. The authors also regret that the funding information was incorrectly shown in the original article.Signed: Sa Zhang, Yan Li, Liuqing Huang, Liuying Huang and Xuetao Luo, 23rd June 2022.Retraction endorsed by Laura Fisher, Executive Editor, RSC Advances. 相似文献
976.
977.
978.
Yanming Miao Xinhao Zhang Jinyao Li Wenli Yang Xiaomin Huang Jinzhi Lv 《RSC advances》2022,12(32):20481
Room-temperature phosphorescent (RTP) N-doped carbon-dots (CNDs) featuring eco-friendliness, low cost and high biocompatibility, are ideal photodynamic antibacterial and anticancer nanomaterials. However, the existing CNDs are limited by low singlet oxygen (1O2) quantum yield, which has become a bottleneck in the development of CNDs. One basic reason is the short T1-state exciton lifetime of CNDs. Herein, triethylenetetramine hexaacetic acid was used to synthesize CNDs via a one-step hydrothermal method. CNDs are characterized with low toxicity, high biocompatibility and ultralong-lifetime RTP (URTP). In addition to the URTP (average lifetime 414 ms) under solid conditions, CNDs even had URTP (average lifetime 320 ms) in a water environment. The ultralong T1 exciton lifetime largely extends the collision time between T1 state excitons and O2 and prolongs the energy transfer time, not only improving the quantum yield (0.63) of singlet oxygen (1O2) in solution, but also facilitating the photodynamic antibacterial and anticancer effects.The URTP CNDs largely extends the collision time between T1 state exciton and O2, which improve quantum yield of singlet oxygen (1O2) in solutions, facilitating the photodynamic antibacterial and anticancer effects. 相似文献
979.
Coronavirus disease 2019 (COVID-19) was first detected in China in December 2019, and declared as a pandemic by the World Health Organization (WHO) on March 11, 2020.To study the clinical features of patients with COVID-19, we analyzed the correlation between some inflammation-related indicators in patients’ serum and the severity of the disease, especially PV (pneumonia volume under CT scan) and pneumonia volume ratio (PVR).Sixty-six COVID-19 patients in Huai’an, China were selected as the research subjects. We collected the clinical data, including general characteristics, clinical symptoms, serum test results and CT performance, explored the relationship between inflammation-related indexes, oxygenation index, PV, PVR, while indicators of mild to moderate patients and severe patients were compared.The most prominent manifestations of COVID-19 patients were fever (47, 71.2%); cough (41, 62.1%), with or without respiratory and other systemic symptoms; There was no difference in gender (P = .567) and age (P = .865) between mild to moderate and severe groups. High sensitivity C-reactive protein (hs-CRP), erythrocyte sedimentation rate (ESR), and interleukin-6 (IL-6) of overall patients were higher than the normal range (P < .001, respectively). hs-CRP was negatively correlated with oxygenation index (OI) (r = –0.55), whereas positively correlated with PV, PVR and ESR (r = 0.89; r = 0.87; r = 0.47, respectively); ESR was negatively correlated with OI (r = –0.45), meanwhile it was positively correlated with PV and PVR (r = 0.44; r = 0.46, respectively). OI was negatively correlated with PV and PVR (r = –0.6, respectively). PV had a clear correlation with PVR (r = 1). Severe patients’ hs-CRP, PV, PVR were higher than mild to moderate group (P = .006; P = .001; P < .001, respectively), but OI was lower (P < .001).The clinical features of COVID-19 were similar to general viral pneumonia. hs-CRP, ESR showed a certain correlation with the PV and PVR, which might play a certain role in assessing the severity of COVID-19. 相似文献
980.
Shaoli Li Shufang Liu Xinchun Zhang Yali Chen Xiaohong Ren 《The Journal of international medical research》2022,50(7)
ObjectiveThis quasi-randomized controlled trial was performed to evaluate the effects of the PRECEDE-PROCEED model (PPM) in enabling mothers of preterm infants to develop care knowledge, skill, and a sense of competence.MethodsAmong 116 mothers of preterm infants, 60 received traditional discharge education (control group) and 56 received PPM discharge education (PPM group). Improvement in knowledge and skills was transformed into the mothers’ routine daily care of infants. The primary outcome was knowledge of preterm infant care. The secondary outcomes were preterm infant care skills and a sense of competence, routine intervention compliance among mothers, and the readmission rate of infants 6 months after discharge.ResultsSix months after discharge, the mean knowledge score and mean skills score were significantly higher in the PPM group than in the control group. The mothers’ sense of competence with respect to both self-efficacy and satisfaction was also significantly better in the PPM group than in the control group. Moreover, intervention behavior compliance and the readmission rate were significantly better in the PPM group than in the control group.ConclusionCare knowledge, skills, and sense of competence in mothers of preterm infants improved after implementation of the PPM. 相似文献