全文获取类型
收费全文 | 513篇 |
免费 | 37篇 |
国内免费 | 51篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 14篇 |
基础医学 | 52篇 |
口腔科学 | 12篇 |
临床医学 | 107篇 |
内科学 | 132篇 |
皮肤病学 | 3篇 |
神经病学 | 13篇 |
特种医学 | 85篇 |
外科学 | 29篇 |
综合类 | 29篇 |
预防医学 | 37篇 |
眼科学 | 9篇 |
药学 | 49篇 |
中国医学 | 6篇 |
肿瘤学 | 21篇 |
出版年
2021年 | 7篇 |
2020年 | 4篇 |
2019年 | 6篇 |
2018年 | 4篇 |
2017年 | 8篇 |
2016年 | 15篇 |
2015年 | 8篇 |
2014年 | 16篇 |
2013年 | 12篇 |
2012年 | 6篇 |
2011年 | 10篇 |
2010年 | 12篇 |
2009年 | 11篇 |
2008年 | 13篇 |
2007年 | 39篇 |
2006年 | 6篇 |
2005年 | 21篇 |
2004年 | 9篇 |
2003年 | 15篇 |
2002年 | 17篇 |
2001年 | 24篇 |
2000年 | 14篇 |
1999年 | 12篇 |
1998年 | 31篇 |
1997年 | 34篇 |
1996年 | 16篇 |
1995年 | 24篇 |
1994年 | 16篇 |
1993年 | 23篇 |
1992年 | 6篇 |
1991年 | 9篇 |
1990年 | 5篇 |
1989年 | 15篇 |
1988年 | 13篇 |
1987年 | 9篇 |
1986年 | 12篇 |
1985年 | 11篇 |
1984年 | 10篇 |
1982年 | 10篇 |
1981年 | 8篇 |
1980年 | 5篇 |
1979年 | 6篇 |
1977年 | 8篇 |
1976年 | 8篇 |
1975年 | 4篇 |
1974年 | 3篇 |
1971年 | 4篇 |
1936年 | 2篇 |
1931年 | 4篇 |
1927年 | 2篇 |
排序方式: 共有601条查询结果,搜索用时 15 毫秒
81.
82.
Chloride secretion in response to guanylin in colonic epithelial from normal and transgenic cystic fibrosis mice. 总被引:9,自引:1,他引:8
下载免费PDF全文
![点击此处可从《British journal of pharmacology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
A. W. Cuthbert M. E. Hickman L. J. MacVinish M. J. Evans W. H. Colledge R. Ratcliff P. W. Seale P. P. Humphrey 《British journal of pharmacology》1994,112(1):31-36
1. Guanylin, a 15 amino acid endogenous gut peptide, increased the short circuit current (SCC) in the epithelium of the mouse colon, but only when applied to the apical and not the basolateral surface. 2. By use of selective blockers of epithelial ion transport and modification of the bathing solution, it was concluded that guanylin increased electrogenic chloride secretion but also had a minor effect on electrogenic sodium absorption. In addition there were small residual currents which remained unresolved. 3. The threshold concentration of guanylin causing a SCC increase was less than 50 nM, but at concentrations 40 times greater no indication of a maximally effective concentration was found. 4. Two guanylin isomers with the same amino acid sequence but with the disulphide bridges joined in an alternate fashion showed no activity. Thus only guanylin with the greatest structural homology to heat stable enterotoxin (STa) showed biological activity. 5. The action of guanylin was virtually eliminated in colonic epithelia from transgenic cystic fibrosis (CF) mice. As these animals lack the chloride channel coded by the CF gene sequence, it is likely that the final effector process in murine colonic epithelia involves the CFTR (cystic fibrosis transmembrane conductance regulator) chloride channel. 6. Opportunistic infections of the gut generating STa lead to diarrhoeal conditions via an action of the toxin on apical guanylin receptors. Thus, as discussed, the CF heterozygote may have a genetic advantage in this circumstance. 相似文献
83.
84.
85.
86.
87.
Pheochromocytoma and the normal adrenal medulla: improved visualization with I-123 MIBG scintigraphy 总被引:1,自引:0,他引:1
Lynn MD; Shapiro B; Sisson JC; Beierwaltes WH; Meyers LJ; Ackerman R; Mangner TJ 《Radiology》1985,155(3):789-792
The radiopharmaceutical iodine 131 metaiodobenzylguanidine (I-131 MIBG) has been shown to locate pheochromocytomas scintigraphically with a false-negative rate of approximately 13%. To improve image quality and reduce the false-negative rate, I-123 was examined as a radioactive label for MIBG, as it has many advantages over I-131, including superior dosimetry and better detection efficiency. Diagnostic doses of 0.5 mCi (18.5 MBq) I-131 MIBG and 10.0 mCi (370.0 MBq) I-123 MIBG with nearly equivalent radiation dosimetries were compared in 18 patients with known or suspected pheochromocytomas. Images of superior quality were obtained with I-123 MIBG in 18 of 18 patients, and in eight cases lesions not visualized on I-131 MIBG scintigraphy were portrayed. A further advantage of I-123 MIBG is that it permits single photon emission computed tomography (SPECT). This was performed in six cases and provided additional information in three cases. The adrenal medullae were definitely visualized using I-123 scintigraphy in eight of 14 patients still possessing adrenal glands, whereas I-131 MIBG images portrayed the adrenal medulla in only one of 14 cases. Five remaining patients had multiple abdominal tumor deposits that were difficult to differentiate from normal adrenal medullae. 相似文献
88.
89.
90.
Splenectomy in myeloid metaplasia 总被引:3,自引:0,他引:3
Between 1960 and 1977, 50 patients with agnogenic myeloid metaplasia were splenectomized. Twenty-five of 26 patients with painful splenomegaly, 4 of 9 patients with refractory hemolytic anemia, 4 of 10 patients with refractory thrombocytopenia, and 4 of 4 patients with portal hypertension showed significant benefit from the procedure. There were five immediate postoperative deaths. Four of these deaths occurred early in our series of splectomies for myeloid metaplasia before 1970. Only one death has occurred in the last 21 patients operated on. Survival following splenectomy averaged 25.5 mo. 相似文献