全文获取类型
收费全文 | 1847篇 |
免费 | 92篇 |
国内免费 | 11篇 |
专业分类
耳鼻咽喉 | 18篇 |
儿科学 | 43篇 |
妇产科学 | 20篇 |
基础医学 | 135篇 |
口腔科学 | 62篇 |
临床医学 | 181篇 |
内科学 | 508篇 |
皮肤病学 | 22篇 |
神经病学 | 104篇 |
特种医学 | 55篇 |
外科学 | 397篇 |
综合类 | 22篇 |
一般理论 | 2篇 |
预防医学 | 49篇 |
眼科学 | 70篇 |
药学 | 145篇 |
中国医学 | 10篇 |
肿瘤学 | 107篇 |
出版年
2024年 | 2篇 |
2023年 | 16篇 |
2022年 | 54篇 |
2021年 | 110篇 |
2020年 | 65篇 |
2019年 | 67篇 |
2018年 | 62篇 |
2017年 | 56篇 |
2016年 | 57篇 |
2015年 | 73篇 |
2014年 | 115篇 |
2013年 | 140篇 |
2012年 | 197篇 |
2011年 | 201篇 |
2010年 | 109篇 |
2009年 | 97篇 |
2008年 | 111篇 |
2007年 | 106篇 |
2006年 | 105篇 |
2005年 | 70篇 |
2004年 | 59篇 |
2003年 | 40篇 |
2002年 | 23篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1999年 | 3篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1988年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1982年 | 1篇 |
1966年 | 1篇 |
排序方式: 共有1950条查询结果,搜索用时 15 毫秒
91.
Sachin Kochrekar Ajit Kalekar Shweta Mehta Pia Damlin Mikko Salomki Sari Granroth Niko Meltola Kavita Joshi Carita Kvarnstrm 《RSC advances》2021,11(32):19844
This study reports the electropolymerization of novel keto functionalized octaethyl metal porphyrins (Zn2+ and Ni2+) in the presence of 4,4′-bipyridine (4,4′-bpy) as a bridging nucleophile. The polymer films were characterized by electrochemical, spectroscopic (UV-Vis, XPS, FT-IR and Raman spectroscopy) and imaging (AFM and SEM) techniques. The absorption and electronic spectra confirm the presence of both porphyrin and 4,4′-bipyridine units in the film. The surface morphology reveals homogeneous film deposition with average roughness values of approx. 8 nm. The theoretical studies performed offered insights into the interplay of different metal centres (Zn2+ and Ni2+) and the keto functionality of the porphyrin unit in the formation of copolymer films. The electrochemical interaction of polymer films with CO2 suggests a reversible trap and release of CO2 with low energy barriers for both the polymers.Electropolymerization of keto functionalized porphyrins and 4,4′-bipyridine. 相似文献
92.
Brahme Radhika Mamulwar Megha Rahane Girish Jadhav Sachin Panchal Narayan Yadav Rajesh Gangakhedkar Raman 《Indian journal of pediatrics》2020,87(4):275-280
Indian Journal of Pediatrics - Youth and adolescents are the priority population to target the interventions as risky behaviors persist and they contribute to almost half of the new Human... 相似文献
93.
94.
95.
Inglese M Makani S Johnson G Cohen BA Silver JA Gonen O Grossman RI 《Journal of neurosurgery》2005,103(2):298-303
OBJECT: Diffuse axonal injury (DAI) is a major complication of traumatic brain injury (TBI) that leads to functional and psychological deficits. Although DAI is frequently underdiagnosed by conventional imaging modalities, it can be demonstrated using diffusion tensor imaging. The aim of this study was to assess the presence and extent of DAI in patients with mild TBI. METHODS: Forty-six patients with mild TBI and 29 healthy volunteers underwent a magnetic resonance (MR) imaging protocol including: dual-spin echo, fluid-attenuated inversion recovery, T2-weighted gradient echo, and diffusion tensor imaging sequences. In 20 of the patients, MR imaging was performed at a mean of 4.05 days after injury. In the remaining 26, MR imaging was performed at a mean of 5.7 years after injury. In each case, mean diffusivity and fractional anisotropy were measured using both whole-brain histograms and regions of interest analysis. No differences in any of the histogram-derived measures were found between patients and control volunteers. Compared with controls, a significant reduction of fractional anisotropy was observed in patients' corpus callosum, internal capsule, and centrum semiovale, and there were significant increases of mean diffusivity in the corpus callosum and internal capsule. Neither histogram-derived nor regional diffusion tensor imaging metrics differed between the two groups. CONCLUSIONS: Although mean diffusivity and fractional anisotropy abnormalities in these patients with TBI were too subtle to be detected with the whole-brain histogram analysis, they are present in brain areas that are frequent sites of DAI. Because diffusion tensor imaging changes are present at both early and late time points following injury, they may represent an early indicator and a prognostic measure of subsequent brain damage. 相似文献
96.
Han Jo Kim Michael Steinhaus Ananth Punyala Sachin Shah Jonathan Charles Elysee Renaud Lafage Tom Riviera Guillermo Mendez Ajiri Ojadi Sharlynn Tuohy Sheeraz Qureshi Michael Urban Chad Craig Virginie Lafage Francis Lovecchio 《The spine journal》2021,21(5):753-764
BACKGROUND CONTEXTEnhanced recovery (ERAS) pathways can help hospitals maximize the incentives of bundled payment models while maintaining high-quality patient care. A key component of an enhanced recovery pathway is the ability to predictably reduce inpatient length of stay, as this is a critical component of the cost equation.PURPOSETo determine the efficacy of an enhanced recovery pathway on reducing length of stay after thoracolumbar adult deformity surgery.STUDY DESIGNSingle surgeon retrospective review of prospectively-collected data.PATIENT SAMPLEForty adult deformity patients who underwent ≥5 levels of fusion to the pelvis (two to L5) with a single surgeon before and after implementation of an ERAS pathway.METHODSThe pathway involved participation by anesthesiology, hospital medicine, and physical therapy, and was designed to achieve goals previously associated with decreased LOS (eg, EBL<1200 mL, procedure time <4.5 hours, avoidance of ICU postoperatively, and mobilization POD0-1). Patients were propensity-score matched 1:1 to a historical cohort (enhanced recovery [ER] and historical [H] cohorts), based on demographics, medical comorbidities, radiographic alignment parameters, and surgical factors. Outcomes were compared to determine the effect of the enhanced recovery pathway. Primary outcomes included LOS and 90-day complications and readmissions.RESULTSAfter matching, gender, BMI, ASA class, preoperative opioid dependence, day of surgery, sagittal alignment parameters, rate of revision surgery, three-column osteotomies, and interbody fusions were comparable between the cohorts (p>.05). In the ER cohort, there was reduced EBL (920±640 vs. 1437±555, p=.004) and no ER patient went to the ICU immediately following surgery, compared with 30% of H patients (p=.022). The ER cohort also had a greater number of patients ambulating by POD1 compared to the H cohort (100% vs. 55%, p=.010). ER patients had a shorter LOS (4.5±1.3 vs. 7.3±4.4 days, p=.010). A 90-day readmission and complications were comparable between the cohorts (p>.05).CONCLUSIONSThe creation of an ERAS pathway for patients undergoing thoracolumbar adult deformity surgery reduced length of stay without negatively affecting short-term morbidity and complications. Given the specificity of this pathway to a single surgeon and hospital, the resources and staffing changes that were instrumental in creating the pathway may not be generalizable to other centers. 相似文献
97.
98.
99.