全文获取类型
收费全文 | 271707篇 |
免费 | 23029篇 |
国内免费 | 7077篇 |
专业分类
耳鼻咽喉 | 3668篇 |
儿科学 | 5281篇 |
妇产科学 | 5630篇 |
基础医学 | 24333篇 |
口腔科学 | 8407篇 |
临床医学 | 24397篇 |
内科学 | 27567篇 |
皮肤病学 | 3175篇 |
神经病学 | 14359篇 |
特种医学 | 7595篇 |
外国民族医学 | 27篇 |
外科学 | 24956篇 |
综合类 | 43843篇 |
现状与发展 | 13篇 |
一般理论 | 31篇 |
预防医学 | 33432篇 |
眼科学 | 3651篇 |
药学 | 27573篇 |
393篇 | |
中国医学 | 30617篇 |
肿瘤学 | 12865篇 |
出版年
2024年 | 1081篇 |
2023年 | 4964篇 |
2022年 | 9443篇 |
2021年 | 12493篇 |
2020年 | 11956篇 |
2019年 | 13024篇 |
2018年 | 11772篇 |
2017年 | 10417篇 |
2016年 | 9587篇 |
2015年 | 9017篇 |
2014年 | 17506篇 |
2013年 | 18844篇 |
2012年 | 16034篇 |
2011年 | 17393篇 |
2010年 | 13972篇 |
2009年 | 12212篇 |
2008年 | 11588篇 |
2007年 | 11807篇 |
2006年 | 10185篇 |
2005年 | 8807篇 |
2004年 | 7345篇 |
2003年 | 6733篇 |
2002年 | 5304篇 |
2001年 | 4657篇 |
2000年 | 4024篇 |
1999年 | 3424篇 |
1998年 | 2868篇 |
1997年 | 2645篇 |
1996年 | 2291篇 |
1995年 | 2129篇 |
1994年 | 1888篇 |
1993年 | 1639篇 |
1992年 | 1507篇 |
1991年 | 1361篇 |
1990年 | 1271篇 |
1989年 | 1163篇 |
1988年 | 993篇 |
1987年 | 890篇 |
1986年 | 882篇 |
1985年 | 2217篇 |
1984年 | 2477篇 |
1983年 | 1543篇 |
1982年 | 2037篇 |
1981年 | 1453篇 |
1980年 | 1300篇 |
1979年 | 1123篇 |
1978年 | 910篇 |
1977年 | 727篇 |
1976年 | 834篇 |
1975年 | 576篇 |
排序方式: 共有10000条查询结果,搜索用时 234 毫秒
71.
《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
72.
����һ���� Ȫ 《中国实用外科杂志》2019,39(3):223-225
妊娠期甲状腺癌的诊治是目前甲状腺疾病诊治的热点和难点问题之一。妊娠期发现甲状腺癌对临床医生和孕妇都是一个极大的挑战,应通过多学科协作,尽快明确诊断,全面、合理的评估孕妇和胎儿的情况,选择最合适的治疗和随诊方式,避免对孕妇和胎儿产生副反应,维持正常孕期,获得最佳的治疗效果。 相似文献
73.
74.
《中国现代医生》2020,58(4):84-86+90
目的评价西药联合穴位贴敷中西医结合治疗复治肺结核的临床疗效。方法选择本院2017年1月~2018年1月收治的60例复治肺结核患者进行分组研究,全部患者根据治疗方法不同随机分为两组,每组各30例。两组均采取西药进行治疗,采用2HRZE/6HRZ标准化疗方案,实验组同时联合穴位贴敷中西医结合进行治疗,治疗后对比分析两组病灶吸收情况及两组临床症状改善情况。结果实验组病灶恶化9例,其病灶显著吸收率达50.0%,总有效率达70.0%,对照组病灶恶化6例,不变5例,其病灶显著吸收率达33.3%,总有效率达63.3%,两组病灶吸收总有效率组间比较,差异具有显著性(P0.05);实验组的疗效指数治疗6个月后显著高于对照组,组间比较,差异具有显著性(P0.05)。结论西药联合穴位贴敷中西医结合治疗复治肺结核疗效确切,可以显著促进病灶吸收,改善临床症状,安全性好,且还可以扶助人体正气,提高机体免疫力,调节全身状态,以达到治疗目的,是治疗复治肺结核的有效方法之一,值得临床广泛推广和应用。 相似文献
75.
《Journal of prosthodontic research》2020,64(2):167-174
PurposeFew investigations have examined the production of single restorations using intraoral scanners (IOS). Data on full-arch scans are rare, and data regarding torsion within the entire arch are very sparsely reported. Therefore, the aim of this study was to examine the deviations of torsion and linear distances in full-arch scans of three IOS based on different scanning principles.MethodsA cobalt-chrome-molybdenum alloy master model (CCMM) with four hemispheres was fabricated by laser sintering. The CCMM was digitized using a laboratory scanner (ATOS-Core/GOM) and scanned with three IOS (Omnicam/Sirona(OC); True Definition/3M(TD); TriosII/Cara-Version/Kulzer(TR)). All scan data were exported in a standard STL-file format and were analyzed with GOM Inspect software (V7.5/GOM). Torsion between the right and left side of the arch and linear accuracy (trueness and precision) were evaluated. After normality was confirmed, all data were subjected to parametric statistical analyses.ResultsThe torsion ranged from 0.07 ± 0.03°(OC) to 0.29 ± 0.14°(TD). Pairwise comparisons showed significant differences between the OC and TD scanners and between the TR and TD scanners. The linear distances ranged from 6 ± 5 μm(OC) to 298 ± 317 μm(TD). Significant differences were observed among all investigated IOS (p = 0.05).ConclusionsAlthough the highest torsion was observed for the TD scanner, it is still not clear whether the differences between the IOS are related to the scanning principle or to the scanning algorithm. Due to the high clinical relevance of full-arch restorations, future studies should consider torsion. Regarding linear accuracy, no general difference related to the scanning principles of the IOSs was observed. 相似文献
76.
77.
78.
79.
80.
目的本文主要研究和探讨护理干预对放疗科头颈部肿瘤放疗患者生活质量的影响。方法将我院2017年2月份至2018年10月份收治的100例头颈部肿瘤放疗患者作为本次研究的对象,在随机原则的指导下把100例患者分为对照组和实验组,每组患者的数量为50例。对照组患者给予常规护理,实验组患者实施护理干预,对两组患者的生活质量、睡眠质量、护理满意度和护理依从性等进行对比分析。结果在生活质量、睡眠质量、护理满意度和护理依从性等方面,组间进行对比分析,实验组都明显优于对照组,P<0.05差异具有统计学意义。结论对头颈部肿瘤放疗患者实施护理干预可以让患者的生活质量、睡眠质量、护理依从性以及护理满意度等都得到显著的改善,从而让患者以一种积极、乐观的心态接受放疗,这对于放疗效果的提高具有重要的作用。总之,这一护理模式应该在临床中进行推广和使用。 相似文献