全文获取类型
收费全文 | 4275篇 |
免费 | 271篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 34篇 |
儿科学 | 115篇 |
妇产科学 | 95篇 |
基础医学 | 584篇 |
口腔科学 | 371篇 |
临床医学 | 344篇 |
内科学 | 1046篇 |
皮肤病学 | 179篇 |
神经病学 | 298篇 |
特种医学 | 90篇 |
外国民族医学 | 4篇 |
外科学 | 424篇 |
综合类 | 34篇 |
一般理论 | 1篇 |
预防医学 | 343篇 |
眼科学 | 46篇 |
药学 | 285篇 |
中国医学 | 18篇 |
肿瘤学 | 248篇 |
出版年
2024年 | 7篇 |
2023年 | 42篇 |
2022年 | 94篇 |
2021年 | 177篇 |
2020年 | 84篇 |
2019年 | 133篇 |
2018年 | 154篇 |
2017年 | 111篇 |
2016年 | 108篇 |
2015年 | 123篇 |
2014年 | 180篇 |
2013年 | 201篇 |
2012年 | 299篇 |
2011年 | 350篇 |
2010年 | 185篇 |
2009年 | 152篇 |
2008年 | 255篇 |
2007年 | 263篇 |
2006年 | 211篇 |
2005年 | 213篇 |
2004年 | 199篇 |
2003年 | 155篇 |
2002年 | 128篇 |
2001年 | 113篇 |
2000年 | 97篇 |
1999年 | 80篇 |
1998年 | 23篇 |
1997年 | 23篇 |
1996年 | 18篇 |
1995年 | 15篇 |
1994年 | 8篇 |
1993年 | 18篇 |
1992年 | 36篇 |
1991年 | 42篇 |
1990年 | 19篇 |
1989年 | 18篇 |
1988年 | 28篇 |
1987年 | 24篇 |
1986年 | 19篇 |
1985年 | 21篇 |
1984年 | 7篇 |
1983年 | 9篇 |
1982年 | 10篇 |
1980年 | 8篇 |
1979年 | 9篇 |
1978年 | 9篇 |
1977年 | 7篇 |
1975年 | 7篇 |
1969年 | 14篇 |
1968年 | 7篇 |
排序方式: 共有4559条查询结果,搜索用时 15 毫秒
101.
The pectoralis major (sternal portion), teres major, latissimus dorsi and deltoid medial muscles has been studied through in the electromyography in 8 male individuals, who practice volleyball, youth category, (age between 15 and 17 (average 16.25), right-handed, involved in volleyball for about one year. The objective was to analyze the potential of action of these muscles engaged in the volleyball movements: service, spike, pass, set and blocking with and without ball. The work was developed in the laboratory of Electromyography and Biomechanics of Posture (Physical Education Faculty - State University of Campinas - UNICAMP). To caption the muscles action potential, surface electrodes were set with conductive gel and fixed on the skin, in the center of the muscles. It was used an electromyography Lynx with 6 channels. The apparatus calibration was 3000 microV; 1199.760 Hz. The sequential experiments without ball were performed for 10 seconds, and the sequential experiments with ball in 12 seconds. RESULTS: None of the muscles presented significative difference (p > 0,05) when compared to the sequential movements executed with and without ball. When compared to the sequential movements executed without ball, the only muscles that presented significative differences (p < 0,05) were: pectoralis major / deltoid and latissimus dorsi / deltoid, for another hand when in the comparative of the movements with ball, all muscles when compared to the latissimus dorsi, presented a significance difference (p < 0,05). It is interesting to observe, that the general average and the standard deviation of the deltoid muscle (medial portion), teres major, and latis-simus dorsi were higher in the sequential movements executed without ball. 相似文献
102.
103.
Prevalence and duration of breast milk feeding in very preterm infants: A 3‐year follow‐up study and a systematic literature review 下载免费PDF全文
104.
105.
106.
This study evaluated the temperature rise on external root surfaces by simulating the removal of metallic posts by applying ultrasound, with or without refrigeration and at different times. The crowns of 30 healthy maxillary central incisors were removed and the roots were treated endodontically. The prosthetic spaces were prepared and impressions were taken with self-curing acrylic resin. After casting with a copper-aluminum alloy, the posts were blasted with aluminum oxide and cemented with resin cement. The specimens were randomly assigned to three groups according to the time of ultrasonic vibration (30, 60, or 120 seconds) and were subdivided into two groups, those cooled with and without water refrigeration. A thermocouple connected to a digital thermometer was positioned on the root external surface and the maximum temperature was recorded. Data were submitted to ANOVA and Tukey's test. Analysis of the results revealed statistical difference among groups (p < 0.01). Ultrasound (with and without water spray) increased root temperature significantly, reaching values of more than 50 degrees C. The exception was the group that used 30 seconds of ultrasound with refrigeration; root temperature reached 35.4 degrees C, making it the only tested condition that remained below the critical value (50 degrees C). 相似文献
107.
108.
109.
110.
Caio Rebouas Fonseca Cafezeiro Mariana Pezzute Lopes Caio Tavares Silva Mnica Samuel vila Luis Fernando B. C. Seguro Sandrigo Mangini Iscara Wozniak Campos Fbio A. Gaiotto Fabiana G. Marcondes‐Braga Fernando Bacal 《American journal of transplantation》2020,20(5):1451-1453
Epipericardial fat necrosis is an uncommon clinical condition of unknown etiology. It typically presents as acute pleuritic chest pain and should be differentiated from acute pulmonary embolism and acute coronary syndrome. This condition is diagnosed by characteristic chest computed tomography findings of an ovoid mediastinal fatty lesion with intrinsic and surrounding soft‐tissue stranding. Treatment of epipericardial fat necrosis includes the administration of anti‐inflammatory agents, and symptoms usually resolve within a few days after treatment initiation. This disease entity has rarely been reported since it was first described in 1957. Most current knowledge of epipericardial fat necrosis is based on case reports that describe this condition in previously healthy individuals. We present the case of a 39‐year‐old woman with a history of heart transplant, who presented with chest pain secondary to epipericardial fat necrosis. Serial computed tomography revealed lesion resolution after appropriate treatment. 相似文献