全文获取类型
收费全文 | 31375篇 |
免费 | 1868篇 |
国内免费 | 533篇 |
专业分类
耳鼻咽喉 | 151篇 |
儿科学 | 117篇 |
妇产科学 | 46篇 |
基础医学 | 1605篇 |
口腔科学 | 1971篇 |
临床医学 | 2727篇 |
内科学 | 1072篇 |
皮肤病学 | 30篇 |
神经病学 | 426篇 |
特种医学 | 1904篇 |
外国民族医学 | 2篇 |
外科学 | 12664篇 |
综合类 | 6099篇 |
预防医学 | 1149篇 |
眼科学 | 226篇 |
药学 | 1997篇 |
60篇 | |
中国医学 | 1358篇 |
肿瘤学 | 172篇 |
出版年
2024年 | 29篇 |
2023年 | 495篇 |
2022年 | 803篇 |
2021年 | 1227篇 |
2020年 | 1435篇 |
2019年 | 923篇 |
2018年 | 884篇 |
2017年 | 1090篇 |
2016年 | 1243篇 |
2015年 | 1114篇 |
2014年 | 2393篇 |
2013年 | 2256篇 |
2012年 | 2198篇 |
2011年 | 2394篇 |
2010年 | 1950篇 |
2009年 | 1824篇 |
2008年 | 1612篇 |
2007年 | 1646篇 |
2006年 | 1401篇 |
2005年 | 1333篇 |
2004年 | 1096篇 |
2003年 | 808篇 |
2002年 | 621篇 |
2001年 | 538篇 |
2000年 | 406篇 |
1999年 | 373篇 |
1998年 | 279篇 |
1997年 | 262篇 |
1996年 | 178篇 |
1995年 | 158篇 |
1994年 | 124篇 |
1993年 | 115篇 |
1992年 | 74篇 |
1991年 | 62篇 |
1990年 | 41篇 |
1989年 | 35篇 |
1988年 | 34篇 |
1987年 | 35篇 |
1986年 | 33篇 |
1985年 | 28篇 |
1984年 | 22篇 |
1983年 | 34篇 |
1982年 | 36篇 |
1981年 | 34篇 |
1980年 | 20篇 |
1979年 | 18篇 |
1978年 | 17篇 |
1977年 | 8篇 |
1976年 | 13篇 |
1975年 | 16篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
《Cirugía espa?ola》2023,101(8):548-554
IntroductionPelvic fractures due to high energy trauma present a high risk of associated injuries that compromise the functional and vital prognosis of the patients. The objective of this study was to analyze the relationship between traumatic pelvic fractures and their associated injuries according to the Tile classification.MethodsRetrospective observational study of patients who suffered traumatic pelvic fractures (Type A, B or C of the Tile classification) with concomitant associated injuries, analyzing hemoglobin levels, between 6/2013 and 1/2016.ResultsA total of 42 patients were included; of those 69% (n = 29) were males, mean age was 48 years. 45% (n = 19) suffered traffic accidents and 26.2% (n = 11) falls. There was a different proportion in pelvic injuries: Tile A (n = 15, 35.7%), B (n = 20, 47.6%), and C (n = 7, 16.6%) of cases. 54.8% (n = 23) underwent surgery, 21.4% (n = 9) needed temporary or definitive external fixation. Significant differences were found between Tile A type and scapula fractures (P=.032), and Tile B with sacral fractures (P=.033) and visceral injuries (P=.049), while there is a tendency without a statistical significal between Tile C and costal fractures. 61.9% (n = 26) needed blood transfusion; 9.5% (n = 4) presented hypovolemic shock.ConclusionsTile A pelvic fractures were associated with scapular fractures, and Tile B with transforaminal fractures of the sacrum and with visceral injuries (lungs, liver and genitourinary). The small number of Tile C prevent us to confirm an association with any pathology, although they are the ones which presnt more hemodynamically instability and thoracic injuries. 相似文献
3.
《Dental materials》2022,38(11):1789-1800
ObjectivesDentin microstructure undergoes changes with age and its materials properties degrade over time. In the present study, we investigate the coupled influence of increased filled tubules and decreased materials properties on the fracture behavior of human dentin.MethodsWe assume degraded materials properties are linked with increased advanced glycation end-products (AGEs) crosslinks in dentin tissue. We use morphological data of human molars to create 2D and 3D models of dentin microstructure, and utilize a phase field fracture framework to study crack growth trajectories. We construct aged dentin samples (i.e., filled tubules and degraded properties) and compare the fracture results with the samples without age-related changes.ResultsThe simulations show an increase in the number of filled tubules can deactivate the toughening mechanisms such as crack deflection and microcracking. In addition, filled tubules have adverse impacts on the ability of peritubular dentin to shield microcracking. We further show how the dentinal tubules’ orientations affect the crack surface growth. We also investigate that an increase in the AGEs level can result in increased brittleness.SignificanceThe developed model and findings of the present study provide region-dependent information on crack growth trajectories as well as more understanding of crack surface growth at the presence of filled tubules. 相似文献
4.
5.
6.
Prithvi Mohandas Rajsirish Bellal Sridharan Senthilvelan Rajagopalan 《Seminars in Arthroplasty》2022,32(2):389-397
BackgroundThe treatment of complex 3- and 4-part proximal humerus fractures (PHFs) in the elderly poses significant challenges because of osteoporosis and fracture comminution. The wide range of surgical options available is evidence of the complex nature of the injury. At present, reverse shoulder replacement is gaining popularity among shoulder surgeons for treating these difficult fractures, and the literature has shown equivalent or superior outcomes with reverse shoulder arthroplasty (RSA). We aimed to analyze the long-term results of these complex PHF treated with reverse shoulder replacement.MethodsFor this study, fractures from 39 patients with a mean age of 63.18 years who were treated with RSA for acute complex fractures of the proximal humerus in our institution between 2013 and 2019 were analyzed (n = 31, acute 4-part fractures; n = 4, acute fracture–dislocation; n = 3, fracture with irreparable cuff tear; n = 1, osteoporotic 2-part fracture). All patients had a standard reverse shoulder replacement (cemented humeral stem n = 37 and uncemented stem n = 2) surgery in a level 1 trauma center. The mean follow-up duration was 60 months (24-111 months). The clinical outcomes (Oxford Shoulder Score and Constant Shoulder Score) and the complications at 6 months, 12 months, and 24 months were analyzed.ResultsOur study found a relatively younger population, with 21 patients (53.84%) aged <66 years. Spearman's correlation showed that younger patients had better signs of improvement in Oxford Shoulder Scores at 2 years (P = .008). The average Oxford Shoulder Score was 39.12 ± 4.327, and the average Constant Shoulder Score was 67.67 on the operated side. The mean active forward elevation was 142.56 ± 22.29º, abduction was 136.538 ± 24.31º, external rotation was 27 ± 9.011º, and internal rotation was 33 ± 20.41º. The overall complication rate of 17.94% (periprosthetic infection n = 2, periprosthetic humerus fracture n = 1, and hematoma evacuation n = 4) in our study was similar to those of recent studies in the literature.ConclusionRSA provides a reliable option for PHFs and offers good results in the form of pain relief and good functional outcomes at 2 years even in a younger age group. Thus, it is fast becoming an important option in treating complex PHF, but we must be wary of the steep learning curve and the complications pertinent to this procedure. 相似文献
7.
8.
目的: 研究经皮椎体后凸成形术治疗骨质疏松性胸腰椎压缩性骨折的疗效。方法: 选取2019年3月至2020年9月内蒙古科技大学包医一附院收治的68例老年性骨质疏松性椎体压缩性骨折患者为研究对象,随机分为对照组和观察组,各34例;对照组应用经皮椎体成形术治疗,观察组应用经皮椎体后凸成形术治疗,对比两种术式的效果。结果: 观察组患者治疗的总有效率为94.1 %,明显高于对照组的73.5 %(P<0.05);观察组伤椎前缘高度、伤椎后缘高度、伤椎中线高度均高于对照组(P<0.05);观察组后凸角(Cobb角)小于对照组(P<0.05),VAS、ODI评分低于对照组(P<0.05);观察组并发症发生率5.9 %低于对照组的29.4 %(P<0.05);观察组生活质量评分各项均高于对照组(P<0.05)。结论: 老年性骨质疏松性椎体压缩骨折患者应用经皮椎体后凸成形术治疗可取得良好的近期疗效,能改善病情,提升其生活质量,此治疗方案适宜在临床中推广应用。 相似文献
9.
BackgroundPost-operative elderly hip fracture patients require significant rehabilitation. Nandrolone is an anabolic steroid used to promote muscle growth. This study aims to examine the effect of nandrolone in improving rehabilitation and quality of life in elderly female patients with hip fractures undergoing hemiarthroplasty.MethodsThis is a double-blinded prospective randomized-controlled-trial consisting of female patients above the age of 65 with an isolated neck of femur fracture planned for a hip hemiarthroplasty. Participants were randomized into two arms of the study – 50 mg intramuscular nandrolone vs normal saline placebo administered on post-operative day 0, and weeks 2, 6 and 12. The participants were followed up across a 1-year period following the surgery. Clinical outcomes such as time taken to achieve rehabilitation milestones, distance of ambulation and thigh muscle girth, and functional scoring with SF-36 questionnaire were recorded at intervals of 2, 6 and 12 weeks, 6 months and 1 year following the surgery.ResultsThere were a total of 23 subjects with 11 in the steroid group and 12 in the placebo group. There was no significant difference in demographics and injury patterns between both groups. There was no significant difference for time taken to achieve various rehabilitation milestones and distance of ambulation. SF-36 scores on discharge and at 1-year follow-up mark were comparable. There was no difference in the complication rate between both groups.ConclusionIntra-muscular Nandrolone after hip surgery in elderly female patients does not result in short to mid-term improved rehabilitation or functional outcomes. Nandrolone did not result in increased short-term complications after hip surgery.Level of evidenceI. 相似文献
10.
目的 分析不同海拔高度高原驻训官兵肾脏健康状况。方法 随机抽取2021-07至2021-10四川阿坝地区驻训部队575名军人的体检报告进行研究,根据驻训海拔高度分为≤2600 m组(255例)和>2600 m组(320例)。血清尿素、肌酐、尿酸任何一项指标超出参考值范围即判断为肾功能异常。根据肾脏彩超检查结果,包括肾尿盐结晶、肾结石、肾囊肿、肾钙化灶等记录肾脏病变情况,出现任何一种阳性结果即判断为肾脏彩超异常。结果 575例中,肾功能三项异常者198例(34.43%),尿酸升高176例(30.61%),肌酐升高39例(6.78%),尿素升高7例(1.22%);肾脏彩超检查异常者88例(15.30%),肾尿盐结晶56例(9.74%),肾结石27例(4.70%),肾囊肿12例(2.09%),肾钙化灶1例(0.17%),肾错构瘤1例(0.17%)。>2600 m组肾功能三项异常、尿酸升高、肾脏彩超异常、肾尿盐结晶和肾囊肿的发生率显著高于≤2600 m组,差异有统计学意义(P<0.001)。结论 高原驻训官兵肾脏检查结果异常多为血清尿酸升高和肾尿盐结晶,且多发生于海拔2600 m以上区域,应重点防治。 相似文献