全文获取类型
收费全文 | 93篇 |
免费 | 17篇 |
出版年
2022年 | 1篇 |
2021年 | 2篇 |
2019年 | 2篇 |
2018年 | 4篇 |
2016年 | 2篇 |
2014年 | 3篇 |
2013年 | 3篇 |
2012年 | 2篇 |
2011年 | 3篇 |
2010年 | 2篇 |
2009年 | 4篇 |
2008年 | 2篇 |
2007年 | 2篇 |
2006年 | 2篇 |
2005年 | 2篇 |
2004年 | 1篇 |
2003年 | 5篇 |
2002年 | 2篇 |
2001年 | 1篇 |
1999年 | 1篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1993年 | 1篇 |
1990年 | 2篇 |
1989年 | 5篇 |
1988年 | 5篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 3篇 |
1984年 | 6篇 |
1983年 | 4篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 4篇 |
1979年 | 5篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1971年 | 4篇 |
1970年 | 2篇 |
1958年 | 1篇 |
1939年 | 1篇 |
1936年 | 1篇 |
1925年 | 1篇 |
1899年 | 1篇 |
排序方式: 共有110条查询结果,搜索用时 31 毫秒
71.
72.
Stanley Kellett Smith 《BMJ (Clinical research ed.)》1899,2(2020):751-752
73.
N. Yi Mok James Chadwick Katherine A.B. Kellett Nigel M. Hooper A. Peter Johnson Colin W.G. Fishwick 《Bioorganic & medicinal chemistry letters》2009,19(23):6770-6774
A novel series of isatin-based inhibitors of β-secretase (BACE-1) have been identified using a virtual high-throughput screening approach. Structure–activity relationship studies revealed structural features important for inhibition. Docking studies suggest these inhibitors may bind within the BACE-1 active site through H-bonding interactions involving the catalytic aspartate residues. 相似文献
74.
A survey of consultant attitudes to psychiatry in six general hospitals is presented and compared with reported findings in general practitioners and medical students.Psychological factors were accepted as important in a variety of medical conditions. Different specialties differed little in their attitudes to neurotic patients and to psychiatrists, younger consultants tending to be more critical. Consultants had a lower level of neuroticism than the general population and medical students, and physicians were less extraverted than surgeons; these personality factors were not related to expressed attitudes.The results suggest that other specialties accept the role of psychiatry, and its integration into the general hospital is not likely to meet with antagonism. 相似文献
75.
76.
Alzheimer and prion diseases are neurodegenerative disorders characterised by the abnormal processing of amyloid-β (Aβ) peptide and prion protein (PrPC), respectively. Recent evidence indicates that PrPC may play a critical role in the pathogenesis of Alzheimer disease. PrPC interacts with and inhibits the β-secretase BACE1, the rate-limiting enzyme in the production of Aβ. More recently PrPC was identified as a receptor for Aβ oligomers and the expression of PrPC appears to be controlled by the amyloid intracellular domain (AICD). Here we review these observations and propose a feedback loop in the normal brain where PrPC exerts an inhibitory effect on BACE1 to decrease both Aβ and AICD production. In turn, the AICD upregulates PrPC expression, thus maintaining the inhibitory effect of PrPC on BACE1. In Alzheimer disease, this feedback loop is disrupted, and the increased level of Aβ oligomers bind to PrPC and prevent it from regulating BACE1 activity.Key words: alzheimer disease, amyloid-β, Aβ oligomers, amyloid intracellular domain, BACE1, presenilin, prion protein 相似文献
77.
The acute regulation of glucose absorption, transport and metabolism in rat small intestine by insulin in vivo. 总被引:3,自引:2,他引:1 下载免费PDF全文
The effect of acute changes in insulin concentrations in vivo on the absorption, transport and metabolism of glucose by rat small intestine in vitro was investigated. Within 2 min of the injection of normal anaesthetized rats with anti-insulin serum, lactate production and glucose metabolism were respectively diminished to 28% and 21% of normal and the conversion of glucose into lactate became quantitative. These changes correlated with the inhibition of two mucosal enzymes, namely the insulin-sensitive enzyme pyruvate dehydrogenase, and phosphofructokinase, which was shown by cross-over measurements to be the rate-limiting enzyme of glycolysis in mucosa. The proportion of glucose translocated unchanged from the luminal perfusate to the serosal medium was simultaneously increased from 45% to 80%. All the changes produced by insulin deficiency were completely reversed with 2 min when antiserum was neutralized by injection of insulin in vivo. The absorption and transport of 3-O-methylglucose were unaffected by insulin. It is concluded that glucose metabolism in rat small intestine is subject to short-term regulation by insulin in vivo and that glucose absorption and transport are regulated indirectly in response to changes in metabolism. Moreover, transport and metabolism compensate in such a way as to deliver the maximal 'effective' amount of glucose to the blood, whether as glucose itself or as lactate for hepatic gluconeogenesis. 相似文献
78.
79.
Interacting systems of the type A + B = C 总被引:3,自引:0,他引:3
80.
Dissociation of hemoglobin into subunits. Monomer formation and the influence of ligands 总被引:6,自引:0,他引:6
The formation of monomer from several hemoglobins has been investigated by sedimentation equilibrium. The use of the split-beam photoelectric scanning absorption optical system has enabled observations to be made routinely down to 1 μg/ml. (6.2 × 10−8m-heme) with strict spectral control of the integrity of the hemoglobin molecule. The results show that the dissociation constant of dimer to monomer at neutral pH and moderate ionic strength is so small that monomer is present in reversible equilibrium with dimer only in fractions too small to be detectable. Any appreciable monomer formation is irreversible and accompanied by usually pronounced spectral changes. This irreversible monomer formation is probably a consequence of the presence of heavy-metal ions in solution and may be inhibited by 10−3m-EDTA. Hemoglobin ligands possessing chelating ability also inhibit monomer formation. 相似文献