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51.
D E Ames R A Asherson J D Coltart V Vassilikos J K Jones G R Hughes 《Annals of the rheumatic diseases》1992,51(1):120-122
Clinical tricuspid stenosis has not previously been reported in patients with systemic lupus erythematosus (SLE). A 25 year old woman with active SLE presented with signs of severe right ventricular failure. Cardiac catheterisation confirmed the diagnosis of tricuspid stenosis and regurgitation together with mitral regurgitation. This patient underwent successful tricuspid and mitral valve replacement. 相似文献
52.
Antioxidant activity of carnosine, homocarnosine, and anserine present in muscle and brain. 总被引:12,自引:1,他引:12 下载免费PDF全文
R Kohen Y Yamamoto K C Cundy B N Ames 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(9):3175-3179
Carnosine, homocarnosine, and anserine are present in high concentrations in the muscle and brain of many animals and humans. However, their exact function is not clear. The antioxidant activity of these compounds has been examined by testing their peroxyl radical-trapping ability at physiological concentrations. Carnosine, homocarnosine, anserine, and other histidine derivatives all showed antioxidant activity. All of these compounds showing peroxyl radical-trapping activity were also electrochemically active as reducing agents in cyclic voltammetric measurements. Furthermore, carnosine inhibited the oxidative hydroxylation of deoxyguanosine induced by ascorbic acid and copper ions. Other roles of carnosine, such as chelation of metal ions, quenching of singlet oxygen, and binding of hydroperoxides, are also discussed. The data suggest a role for these histidine-related compounds as endogenous antioxidants in brain and muscle. 相似文献
53.
54.
G F Ames J Lever 《Proceedings of the National Academy of Sciences of the United States of America》1970,66(4):1096-1103
The high-affinity (K(m) = 3 x 10(-8) M) transport system for histidine in Salmonella typhimurium has been resolved into three components: J, K, and P. J, which is a histidine-binding protein released by osmotic shock, is specified by the hisJ gene: hisJ mutants lack the binding protein and are defective in histidine transport. Another class of mutants-dhuA, which is closely linked to hisJ-has five times the normal level of binding protein and has an increased rate of histidine transport. P, which is a protein specified by the hisP gene, is required for J binding protein to be operative in transport. hisP mutants, though defective in transport, have normal levels of J binding protein. K, a third transport component, works in parallel to J, and also requires the P protein in order to be operative in transport. A second histidine-binding protein has been found but its relation to K is unclear. hisJ, dhuA, and hisP have been mapped and are in a cluster (near purF) on the S. typhimurium chromosome. 相似文献
55.
A change in anticoagulation monitoring improves safety,reduces transfusion,and reduces costs in infants on cardiopulmonary bypass 下载免费PDF全文
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Sheena G Sullivan Sandra Carlson Allen C Cheng Monique BN Chilver Dominic E Dwyer Melissa Irwin Jen Kok Kristine Macartney Jennifer MacLachlan Cara Minney-Smith David Smith Nigel Stocks Janette Taylor Ian G Barr 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2020,25(47)
58.
Natural killer (NK) cells can mediate the rejection of bone marrow allografts and exist as subsets based on expression of inhibitory/activating receptors that can bind MHC. In vitro data have shown that NK subsets bearing Ly49 receptors for self-MHC class I have intrinsically higher effector function, supporting the hypothesis that NK cells undergo a host MHC-dependent functional education. These subsets also play a role in bone marrow cell (BMC) allograft rejection. Thus far, little in vivo evidence for this preferential licensing across mouse strains with different MHC haplotypes has been shown. We assessed the intrinsic response potential of the different Ly49(+) subsets in BMC rejection by using β2-microglobulin deficient (β2m(-/-)) mice as donors. Using congenic and allogeneic mice as recipients and depleting the different Ly49 subsets, we found that NK subsets bearing Ly49s, which bind "self-MHC" were found to be the dominant subset responsible for β2m(-/-) BMC rejection. This provides in vivo evidence for host MHC class I-dependent functional education. Interestingly, all H2(d) strain mice regardless of background were able to resist significantly greater amounts of β2m(-/-), but not wild-type BMC than H2(b) mice, providing evidence that the rheostat hypothesis regarding Ly49 affinities for MHC and NK-cell function impacts BMC rejection capability. 相似文献
59.
PS Spencer K Vandemaele M Richer VS Palmer S Chungong M Anker Y Ayana ML Opoka BN Klaucke A Quarello JK Tumwine 《African health sciences》2013,13(2):183-204
Background
Nodding Syndrome is a seizure disorder of children in Mundri County, Western Equatoria, South Sudan. The disorder is reported to be spreading in South Sudan and northern Uganda.Objective
To describe environmental, nutritional, infectious, and other factors that existed before and during the de novo 1991 appearance and subsequent increase in cases through 2001.Methods
Household surveys, informant interviews, and case-control studies conducted in Lui town and Amadi village in 2001–2002 were supplemented in 2012 by informant interviews in Lui and Juba, South Sudan.Results
Nodding Syndrome was associated with Onchocerca volvulus and Mansonella perstans infections, with food use of a variety of sorghum (serena) introduced as part of an emergency relief program, and was inversely associated with a history of measles infection. There was no evidence to suggest exposure to a manmade neurotoxic pollutant or chemical agent, other than chemically dressed seed intended for planting but used for food. Food use of cyanogenic plants was documented, and exposure to fungal contaminants could not be excluded.Conclusion
Nodding Syndrome in South Sudan has an unknown etiology. Further research is recommended on the association of Nodding Syndrome with onchocerciasis/mansonelliasis and neurotoxins in plant materials used for food. 相似文献60.
BN Mayanja E Kabunga B Masiira R Lubega P Kaleebu J Seeley 《African health sciences》2013,13(2):311-319