全文获取类型
收费全文 | 17153篇 |
免费 | 1235篇 |
国内免费 | 610篇 |
专业分类
耳鼻咽喉 | 44篇 |
儿科学 | 49篇 |
妇产科学 | 32篇 |
基础医学 | 1256篇 |
口腔科学 | 24篇 |
临床医学 | 1409篇 |
内科学 | 1163篇 |
皮肤病学 | 90篇 |
神经病学 | 235篇 |
特种医学 | 1541篇 |
外国民族医学 | 1篇 |
外科学 | 2993篇 |
综合类 | 3026篇 |
现状与发展 | 1篇 |
预防医学 | 382篇 |
眼科学 | 604篇 |
药学 | 2626篇 |
8篇 | |
中国医学 | 3268篇 |
肿瘤学 | 246篇 |
出版年
2024年 | 47篇 |
2023年 | 201篇 |
2022年 | 610篇 |
2021年 | 815篇 |
2020年 | 597篇 |
2019年 | 533篇 |
2018年 | 581篇 |
2017年 | 553篇 |
2016年 | 647篇 |
2015年 | 639篇 |
2014年 | 1386篇 |
2013年 | 1151篇 |
2012年 | 1266篇 |
2011年 | 1348篇 |
2010年 | 1011篇 |
2009年 | 954篇 |
2008年 | 924篇 |
2007年 | 908篇 |
2006年 | 847篇 |
2005年 | 702篇 |
2004年 | 598篇 |
2003年 | 458篇 |
2002年 | 363篇 |
2001年 | 349篇 |
2000年 | 277篇 |
1999年 | 218篇 |
1998年 | 159篇 |
1997年 | 140篇 |
1996年 | 126篇 |
1995年 | 82篇 |
1994年 | 72篇 |
1993年 | 66篇 |
1992年 | 56篇 |
1991年 | 34篇 |
1990年 | 41篇 |
1989年 | 29篇 |
1988年 | 36篇 |
1987年 | 20篇 |
1986年 | 15篇 |
1985年 | 34篇 |
1984年 | 14篇 |
1983年 | 13篇 |
1982年 | 18篇 |
1981年 | 14篇 |
1980年 | 8篇 |
1979年 | 16篇 |
1978年 | 5篇 |
1977年 | 10篇 |
1976年 | 3篇 |
1969年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
BackgroundProximal tibia vara has drawn interest since the concept of constitutional varus was introduced. Proximal tibia vara is a condition where the knee varus tilt the tibia condyle medially and shift the tibial articular surface medially. This condition affects medial proximal tibial angle measurements and the placement of the tibial implant in knee replacement surgery. Thus, it challenged the neutral knee arthroplasty alignment target because some people may present a proximal tibia vara. This study assesses the prevalence of the proximal tibia vara and the correlation to knee osteoarthritis grade.MethodsThis retrospective study was carried out from January 2021 to June 2021. Eighty-five limbs were included with the following inclusion criteria: knee osteoarthritis patients who received a long view lower extremity radiograph. The exclusions criteria were (1) patients who had undergone arthroplasty and lower extremity surgery before and (2) valgus knee deformity. The outcomes in this study were HKAA, MAD, TAD, MPTA, PTRP, LDFA, and PTS. Intraclass correlation (ICC) using two-way mixed was used to assess the reproducibility of the radiographic parameters. Multiple logistic regression was used to evaluate the correlation between knee osteoarthritis grade and radiographs parameters (MAD and TAD).ResultA total 85 limbs from 52 patients were assessed in this study. Proximal tibia vara was found in 18 knees (21%.). The logistic regression was performed to assess the correlation between the severity of the knee osteoarthritis and radiographic parameters (MAD, TAD, LDFA, and PTS) with an overall p-value < 0.001 and pseudo-R2 = 0.29.ConclusionA significant portion of patients with knee osteoarthritis have proximal tibia vara, and it is a pre-existing condition. Since the pre-existing proximal tibia vara affects preoperative measurements, a long-standing lower extremity x-ray is recommended to be obtained as part of knee replacement preparation. 相似文献
2.
《Radiography》2022,28(3):663-667
IntroductionAnti-scatter grids efficiently reduce scatter radiation from reaching the imaging receptor, enhancing image quality; however, the patient radiation dose increases in the process. There is disagreement regarding the thickness thresholds for which anti-scatter grids are beneficial. This study aims to establish a thickness threshold for the use of anti-scatter grids to optimise adult knee radiography.MethodsThe study consisted of two phases. In Phase 1 phantom knee radiographs were acquired at varying thicknesses (10–16 cm) and tube voltages (60–80 kV). For each thickness and tube voltage, images with and without an anti-scatter grid were obtained. In Phase 2, two radiologists and three radiographers, evaluated the image quality of these images. Visual Grading Analysis (VGA) scores were analysed using Visual Grading Characteristics (VGC) based on the visualisation of five anatomic criteria.ResultsThe average DAP decreased by 72.1% and mAs by 73.1% when removing the anti-scatter grid. The VGC revealed that overall images taken with an anti-scatter grid have better image quality (AUC ≥0.5 for all comparisons). However, the anti-scatter grids could be removed for thicknesses 10, 12 and 14 cm in conjunction with using 80 kVp,.ConclusionAnti-scatter grids can be removed when imaging adult knees between 10 and 12 cm using any kVp setting since the radiation dose is reduced without significantly affecting image quality. For thicknesses >12 cm, the use of anti-scatter grids significantly improves image quality; however, the radiation dose to the patient is increased. The exception is at 14 cm used with 80 kVp, where changes in image quality were insignificant.Implications for practiceOptimisation by removing anti-scatter grids in adult knee radiography seems beneficial below 12 cm thickness with any kVp value. Since the average knee thickness ranges between 10 and 13 cm, anti-scatter grid can be removed for most patients. Nevertheless, further studies are recommended to test if this phantom-based threshold applies to human subjects. 相似文献
3.
4.
5.
6.
《Osteoarthritis and cartilage / OARS, Osteoarthritis Research Society》2020,28(11):1412-1426
7.
Gian Eugenio Tontini Guido Manfredi Stefania Orlando Helmut Neumann Maurizio Vecchi Elisabetta Buscarini Luca Elli 《Digestive endoscopy》2019,31(6):627-643
Over the last decade, impressive technological advances have occurred in ultrasonography and small‐bowel endoscopy. Nowadays, endoscopic ultrasonography is an essential diagnostic tool and a therapeutic weapon for pancreatobiliary disorders. Capsule endoscopy and device‐assisted enteroscopy have quickly become the reference standard for the diagnosis of small‐bowel luminal diseases, thereby leading to radical changes in diagnostic and therapeutic pathways. We herein provide an up‐to‐date overview of the latest advances in endoscopic ultrasonography and small‐bowel endoscopy, focusing on the emerging paradigms and technological innovations that might improve clinical practice in the near future. 相似文献
8.
9.
Ryo Tanaka Kenta Hirohama Junya Ozawa 《Revista brasileira de fisioterapia (S?o Carlos (S?o Paulo, Brazil))》2019,23(3):266-272
ObjectiveTo verify if the relationship between pain catastrophizing and pain worsening would be mediated by muscle weakness and disability in patients with symptomatic knee osteoarthritis.MethodsThis was a cross-sectional study in a hospital out-patient setting. Convenience sampling was used with a total of 50 participants with symptomatic knee osteoarthritis. Pain and the activities of daily livings (ADL) were assessed using the Knee Injury and Osteoarthritis Outcome Score (KOOS) subscale. Pain catastrophizing was assessed using the Coping Strategy Questionnaire (CSQ) subscale. Muscle strength of knee extension and 30-s chair stand test (30CST) were also assessed. Path analysis was performed to test the hypothetical model. Goodness of fit of models were assessed by using statistical parameters such as the chi-square value, goodness of fit index (GFI), adjusted goodness of fit index (AGFI), comparative fit index (CFI), and root mean square error of approximation (RMSEA).ResultsThe chi-square values were not significant (chi-square = 0.283, p = 0.594), and the indices of goodness of fit were high, implying a valid model (GFI = 1.000; AGFI = 0.997; CFI = 1.000; RMSEA = 0.000). Pain was influenced significantly by muscle strength and ADL; muscle strength was influenced significantly by ADL via 30CST; ADL was influenced by pain catastrophizing.ConclusionThe relationship between pain catastrophizing with pain worsening are mediated by muscle weakness and disability. 相似文献
10.