全文获取类型
收费全文 | 1052篇 |
免费 | 67篇 |
国内免费 | 34篇 |
专业分类
儿科学 | 79篇 |
妇产科学 | 9篇 |
基础医学 | 105篇 |
口腔科学 | 34篇 |
临床医学 | 166篇 |
内科学 | 203篇 |
皮肤病学 | 17篇 |
神经病学 | 29篇 |
特种医学 | 122篇 |
外科学 | 138篇 |
综合类 | 19篇 |
预防医学 | 68篇 |
眼科学 | 34篇 |
药学 | 89篇 |
肿瘤学 | 41篇 |
出版年
2022年 | 11篇 |
2021年 | 11篇 |
2020年 | 7篇 |
2019年 | 8篇 |
2018年 | 28篇 |
2017年 | 15篇 |
2016年 | 14篇 |
2015年 | 17篇 |
2014年 | 33篇 |
2013年 | 43篇 |
2012年 | 44篇 |
2011年 | 46篇 |
2010年 | 41篇 |
2009年 | 40篇 |
2008年 | 42篇 |
2007年 | 55篇 |
2006年 | 43篇 |
2005年 | 40篇 |
2004年 | 31篇 |
2003年 | 20篇 |
2002年 | 30篇 |
2001年 | 20篇 |
2000年 | 21篇 |
1999年 | 31篇 |
1998年 | 42篇 |
1997年 | 41篇 |
1996年 | 53篇 |
1995年 | 33篇 |
1994年 | 37篇 |
1993年 | 23篇 |
1992年 | 14篇 |
1991年 | 13篇 |
1990年 | 10篇 |
1989年 | 26篇 |
1988年 | 27篇 |
1987年 | 20篇 |
1986年 | 16篇 |
1985年 | 14篇 |
1984年 | 9篇 |
1983年 | 8篇 |
1982年 | 13篇 |
1981年 | 13篇 |
1980年 | 12篇 |
1979年 | 3篇 |
1978年 | 4篇 |
1977年 | 4篇 |
1976年 | 10篇 |
1975年 | 8篇 |
1971年 | 3篇 |
1957年 | 1篇 |
排序方式: 共有1153条查询结果,搜索用时 31 毫秒
1.
2.
3.
C Leclercq G Maiani A Polito A Ferro-Luzzi 《Nutrition (Burbank, Los Angeles County, Calif.)》1991,7(5):350-354
The p-aminobenzoic acid (PABA) test has been successfully used as an indicator of completeness of 24-h urine collection in field studies of the general population. Our study was designed to investigate its validity for elderly people. Urinary excretion of fractionated oral doses of PABA was measured in 21 young control subjects (19-39 yr old) and 356 elderly (60-89 yr old) men and women. PABA excretion over 24 h was lower in elderly than in control subjects. Subjects aged greater than or equal to 70 yr had a lower recovery of the PABA dose than subjects aged 60-69 yr over the first 24 h, followed by a higher recovery over the next 24-48 h. The cumulative 48-h recovery was similar in all age classes of elderly subjects. However, 48% of the elderly subjects had a cumulative PABA recovery below the conventional cutoff for completeness (85%). These subjects also had consistently lower creatinine output and urinary volume. The lower 24-h urinary PABA recovery over 70 yr of age is interpreted to reflect the delayed renal clearance of the marker substance and indicates that the PABA test is unsuitable for this age group. The low 48-h cumulative recoveries found in all age classes of the elderly are thought to be caused by small unreported losses, which are recurrent in free-living populations. 相似文献
4.
5.
We used arthrotomography to study the glenoid labrum in 114 patients. Sixty-nine of the patients had anatomic instability of the shoulder (including recurrent dislocation and subluxation of the shoulder), and 45 patients had functional instability of the shoulder (denoted by chronic pain, clicking of the joint, and the sensation that an unstable condition exists without the objective signs of it). Labral tears were revealed arthrotomographically in 86% of the patients with anatomic instability, while only 40% of the patients with functional instability had labral abnormalities, and these were primarily of minor severity. Fifty-six patients (44 of whom had anatomic instability; 12, functional instability) required surgery. The surgical findings were correlated with the arthrotomographic findings, and no false-positive results were revealed. However, arthrotomography demonstrated only part of the pathologic condition of two patients. These results confirm that there is a strong correlation between labral pathologic conditions and anatomic instability of the shoulder. Arthrotomographic studies have a great impact on the selection of therapy in cases of both anatomic and functional instability of the shoulder. 相似文献
6.
Hausegger KA; Cragg AH; Lammer J; Lafer M; Fluckiger F; Klein GE; Sternthal MH; Pilger E 《Radiology》1994,190(1):199
7.
Rosenberg ZS; Jahss MH; Noto AM; Shereff MJ; Cheung Y; Frey CC; Norman A 《Radiology》1988,167(2):489-493
Computed tomography (CT) was performed in 42 patients with 49 clinically suspected tears of the posterior tibial tendon. Twenty-eight of the 49 suspected tears were subsequently surgically explored and repaired. Three patterns of tendon abnormalities were recognized on CT scans: type I-intact, hypertrophied, heterogeneous tendon; type II-attenuated tendon; and type III-absence of a portion of a tendon. Types I and II correlated with partial rupture seen during surgery, and type III correlated with complete rupture of the tendon. CT findings were accurate in 96% of the patients who underwent surgery. In four cases (14%), tendon rupture was seen on CT scans, but the extent of the injury was underestimated and the rupture was misclassified. Reactive periostitis of the distal tibia was seen in 71% of diseased tendons and may represent an important factor in the diagnosis of tendon rupture. 相似文献
8.
9.
Peroneus quartus muscle: MR imaging features 总被引:2,自引:0,他引:2
10.