全文获取类型
收费全文 | 29053篇 |
免费 | 2076篇 |
国内免费 | 358篇 |
专业分类
耳鼻咽喉 | 574篇 |
儿科学 | 407篇 |
妇产科学 | 468篇 |
基础医学 | 5061篇 |
口腔科学 | 425篇 |
临床医学 | 2502篇 |
内科学 | 5570篇 |
皮肤病学 | 1267篇 |
神经病学 | 2152篇 |
特种医学 | 1988篇 |
外科学 | 3305篇 |
综合类 | 119篇 |
现状与发展 | 3篇 |
一般理论 | 12篇 |
预防医学 | 1228篇 |
眼科学 | 755篇 |
药学 | 2769篇 |
中国医学 | 422篇 |
肿瘤学 | 2460篇 |
出版年
2024年 | 22篇 |
2023年 | 261篇 |
2022年 | 844篇 |
2021年 | 1319篇 |
2020年 | 628篇 |
2019年 | 898篇 |
2018年 | 1008篇 |
2017年 | 862篇 |
2016年 | 1280篇 |
2015年 | 1746篇 |
2014年 | 1931篇 |
2013年 | 2096篇 |
2012年 | 3001篇 |
2011年 | 2779篇 |
2010年 | 1656篇 |
2009年 | 1344篇 |
2008年 | 1672篇 |
2007年 | 1642篇 |
2006年 | 1340篇 |
2005年 | 1135篇 |
2004年 | 920篇 |
2003年 | 796篇 |
2002年 | 647篇 |
2001年 | 344篇 |
2000年 | 281篇 |
1999年 | 210篇 |
1998年 | 106篇 |
1997年 | 81篇 |
1996年 | 52篇 |
1995年 | 54篇 |
1994年 | 35篇 |
1993年 | 42篇 |
1992年 | 46篇 |
1991年 | 55篇 |
1990年 | 46篇 |
1989年 | 44篇 |
1988年 | 36篇 |
1987年 | 35篇 |
1986年 | 18篇 |
1985年 | 23篇 |
1984年 | 17篇 |
1983年 | 13篇 |
1982年 | 7篇 |
1981年 | 15篇 |
1980年 | 9篇 |
1979年 | 18篇 |
1978年 | 10篇 |
1977年 | 10篇 |
1976年 | 11篇 |
1975年 | 9篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
Moderate sedatives have been increasingly used to improve patient comfort during flexible bronchoscopy (FB). However, routine use of moderate sedation during FB is controversial because its efficacy and safety are not well established.This study aims to evaluate the efficacy and safety of moderate sedation during FB.A search was made of Medline, EMBASE, and the Cochrane Library to May 2014.Randomized controlled trials (RCTs) and quasi-RCTs were included.The main analysis was designed to examine the efficacy of moderate sedation during FB in sedation than no-sedation.The willingness to repeat FB was significantly more in sedation than no-sedation (odds ratio [OR] 2.30; 95% confidence interval [CI] 1.11–4.73; P = 0.02; I2 = 22.5). The duration of FB was shorter in sedation group than no-sedation group (standardized mean difference [SMD] −0.21; 95% CI −0.38 to −0.03; P = 0.02; I2 = 78.3%). Event of hypoxia was not significantly different between sedation and no-sedation groups (OR 0.86; 95% CI 0.42–1.73; P = 0.67; I2 = 0%). The SpO2 during procedure was not different between sedation and no-sedation groups (SMD −0.14; 95% CI −0.37 to 0.08; P = 0.21; I2 = 49.9%). However, in subgroup analysis without supplemental oxygen, the SpO2 was significantly lower in sedation than no-sedation group (SMD −0.45; 95% CI −0.78 to −0.11; P = 0.01; I2 = 0.0%).According to this meta-analysis, moderate sedation in FB would be useful in patients who will require repeated bronchoscopies as well as safe in respiratory depression. To our knowledge, although the various sedative drugs are already used in the real field, this analysis was the first attempt to quantify objective results. We anticipate more definite and studies designed to elucidate standardized outcomes for moderate sedation in FB. 相似文献
2.
3.
4.
5.
Cheong-Il Shin Sang Joon Park Ji-Hyun Kim Yeonyee Elizabeth Yoon Eun-Ah Park Bon-Kwon Koo Whal Lee 《Korean journal of radiology》2021,22(5):688
ObjectiveTo compare the lumen parameters measured by the location-adaptive threshold method (LATM), in which the inter- and intra-scan attenuation variabilities of coronary computed tomographic angiography (CCTA) were corrected, and the scan-adaptive threshold method (SATM), in which only the inter-scan variability was corrected, with the reference standard measurement by intravascular ultrasonography (IVUS).Materials and MethodsThe Hounsfield unit (HU) values of whole voxels and the centerline in each of the cross-sections of the 22 target coronary artery segments were obtained from 15 patients between March 2009 and June 2010, in addition to the corresponding voxel size. Lumen volume was calculated mathematically as the voxel volume multiplied by the number of voxels with HU within a given range, defined as the lumen for each method, and compared with the IVUS-derived reference standard. Subgroup analysis of the lumen area was performed to investigate the effect of lumen size on the studied methods. Bland-Altman plots were used to evaluate the agreement between the measurements.ResultsLumen volumes measured by SATM was significantly smaller than that measured by IVUS (mean difference, 14.6 mm3; 95% confidence interval [CI], 4.9–24.3 mm3); the lumen volumes measured by LATM and IVUS were not significantly different (mean difference, −0.7 mm3; 95% CI, −9.1–7.7 mm3). The lumen area measured by SATM was significantly smaller than that measured by LATM in the smaller lumen area group (mean of difference, 1.07 mm2; 95% CI, 0.89–1.25 mm2) but not in the larger lumen area group (mean of difference, −0.07 mm2; 95% CI, −0.22–0.08 mm2). In the smaller lumen group, the mean difference was lower in the Bland-Altman plot of IVUS and LATM (0.46 mm2; 95% CI, 0.27–0.65 mm2) than in that of IVUS and SATM (1.53 mm2; 95% CI, 1.27–1.79 mm2).ConclusionSATM underestimated the lumen parameters for computed lumen segmentation in CCTA, and this may be overcome by using LATM. 相似文献
6.
7.
Yeon Seok Lee June Hyunkyung Lee Jae Eun Choi Joo Young Kim Tae Young Han 《Pediatric dermatology》2021,38(1):290-291
Erythema induratum of Bazin (EIB) is a form of tuberculid resulting from hypersensitivity to tuberculosis antigen. EIB occurs most commonly in middle‐aged women and is not typically seen in children. Here, we present a rare case of EIB, presenting as a chronic nodular panniculitis, in a 10‐year‐old Korean boy. 相似文献
8.
Jae Eun Choi Tyler Werbel Zhenping Wang Chia Chi Wu Tony L. Yaksh Anna Di Nardo 《Journal of dermatological science》2019,93(1):58-64
Background
Rosacea is a chronic inflammatory skin condition whose etiology has been linked to mast cells and the antimicrobial peptide cathelicidin LL-37. Individuals with refractory disease have demonstrated clinical benefit with periodic injections of onabotulinum toxin, but the mechanism of action is unknown.Objectives
To investigate the molecular mechanism by which botulinum toxin improves rosacea lesions.Methods
Primary human and murine mast cells were pretreated with onabotulinum toxin A or B or control. Mast cell degranulation was evaluated by β-hexosaminidase activity. Expression of botulinum toxin receptor Sv2 was measured by qPCR. The presence of SNAP-25 and VAMP2 was established by immunofluorescence. In vivo rosacea model was established by intradermally injecting LL-37 with or without onabotulinum toxin A pretreatment. Mast cell degranulation was assessed in vivo by histologic counts. Rosacea biomarkers were analyzed by qPCR of mouse skin sections.Results
Onabotulinum toxin A and B inhibited compound 48/80-induced degranulation of both human and murine mast cells. Expression of Sv2 was established in mouse mast cells. Onabotulinum toxin A and B increased cleaved SNAP-25 and decreased VAMP2 staining in mast cells respectively. In mice, injection of onabotulinum toxin A significantly reduced LL-37-induced skin erythema, mast cell degranulation, and mRNA expression of rosacea biomarkers.Conclusions
These findings suggest that onabotulinum toxin reduces rosacea-associated skin inflammation by directly inhibiting mast cell degranulation. Periodic applications of onabotulinum toxin may be an effective therapy for refractory rosacea and deserves further study. 相似文献9.
10.