全文获取类型
收费全文 | 2007篇 |
免费 | 304篇 |
国内免费 | 39篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 105篇 |
妇产科学 | 22篇 |
基础医学 | 111篇 |
口腔科学 | 26篇 |
临床医学 | 317篇 |
内科学 | 704篇 |
皮肤病学 | 61篇 |
神经病学 | 180篇 |
特种医学 | 282篇 |
外科学 | 253篇 |
综合类 | 34篇 |
预防医学 | 91篇 |
眼科学 | 16篇 |
药学 | 68篇 |
中国医学 | 1篇 |
肿瘤学 | 65篇 |
出版年
2023年 | 53篇 |
2021年 | 38篇 |
2020年 | 95篇 |
2019年 | 14篇 |
2018年 | 90篇 |
2017年 | 71篇 |
2016年 | 72篇 |
2015年 | 65篇 |
2014年 | 101篇 |
2013年 | 123篇 |
2012年 | 45篇 |
2011年 | 37篇 |
2010年 | 82篇 |
2009年 | 116篇 |
2008年 | 54篇 |
2007年 | 53篇 |
2006年 | 47篇 |
2005年 | 31篇 |
2004年 | 23篇 |
2003年 | 21篇 |
2002年 | 22篇 |
2001年 | 36篇 |
2000年 | 19篇 |
1999年 | 29篇 |
1998年 | 83篇 |
1997年 | 95篇 |
1996年 | 80篇 |
1995年 | 69篇 |
1994年 | 52篇 |
1993年 | 52篇 |
1992年 | 33篇 |
1991年 | 24篇 |
1990年 | 29篇 |
1989年 | 55篇 |
1988年 | 51篇 |
1987年 | 29篇 |
1986年 | 25篇 |
1985年 | 31篇 |
1984年 | 25篇 |
1983年 | 25篇 |
1982年 | 19篇 |
1981年 | 21篇 |
1980年 | 18篇 |
1979年 | 24篇 |
1978年 | 15篇 |
1977年 | 16篇 |
1976年 | 15篇 |
1975年 | 15篇 |
1974年 | 16篇 |
1973年 | 20篇 |
排序方式: 共有2350条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
6.
7.
Ralls PW; Johnson MB; Kanel G; Dobalian DM; Colletti PM; Boswell WD Jr; Radin DR; Halls JM 《Radiology》1986,161(2):451-454
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease. 相似文献
8.
A. Di Stefano M. Wittner B. Corman 《Pflügers Archiv : European journal of physiology》1991,419(3-4):327-331
The maximal urinary osmolality that can be reached by the kidney is reduced with age. This may be due to impaired NaCl transport by the medullary thick ascending limb of Henle's loop, which is part of the renal concentrating mechanism and is modulated by antidiuretic hormone (ADH). We therefore tested in vitro a possible age-related change in the transport capacity and in the response of this nephron segment to ADH in young (1–2 months) and old (20–24 months) mice. The transepithelial potential difference (V
te) was significantly higher in young mice (+8.5±0.4 mV, n=13) than in old ones (+6.6±0.5 mV, n=17). Addition of 0.1 nmol.l–1 ADH to the bath solution significantly increased V
te by 5.2±0.5 mV in the young and by 3.1±0.6 mV in the old animals. Application of dibutyryl-cAMP (0.1 mmol.1–1) did not further increase the hormonal response in both groups. The ADH-mediated increase in the corresponding equivalent short-circuit current (I
SC = V
te/Rte) was twice as great in young mice as in old, indicating that the stimulation of NaCl transport by ADH across the medullary thick ascending limb is significantly reduced with age. These results suggest that the previously reported age-related defect in the urinary concentrating ability of the kidney is partly due to a decreased response of the medullary thick ascending limb to ADH. 相似文献
9.
10.