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排序方式: 共有459条查询结果,搜索用时 15 毫秒
1.
N Durán Y Makita L H Innocentini 《Biochemical and biophysical research communications》1979,88(2):642-648
The presence of enzymically generated triplet acetone in red cells and energy transfer to eosin, rose bengal and 9,10-dibromoanthracene-2-sulfonate was indicate by: (1) product distribution; (2) KET τo, similar to the 2-methylpropanal/peroxidase/O2 system; (3) correlation between hemolysis, oxygen uptake and photon emission; (4) membrane protection by energy acceptors, and (5) by comparison of the 2-methylpropanal/peroxidase/O2 system with 2-methylpropanal/red cells/membranes/O2 and 2-methylpropanal/acid extractable protein from red cells membrane/O2 systems, which have a high peroxidase activity.This is the first report of a biological system producing a photohemolysis effect in the dark. 相似文献
2.
Serotonin metabolism was studied in several brain regions of control and Streptozotocin-treated male Wistar rats. After induction of diabetes, the animals were killed at 24 hours. Concentrations of brain tryptophan show a generalized increase in all brain regions, being only significant in medulla-pons. Serotonin levels do not change, while 5-HIAA concentrations, as well as the ratio 5-HIAA/5-HT, show significant increases in medulla-pons and mid-brain. 相似文献
3.
Summary Fe (III) and Cu (II) each at 50 M in four commercial strains of Saccharomyces cerevisiae induced an increase of NAD(P)+ reduction in one strain (Turkish), but two others (Chilean and Brazilian), the presence of Fe(III) and/or Cu(II) diminished NAD(P)+ reduction presumably due to free radicais formation inside these living cells. Suprisingly, in the American strain, Fe(III) induced a decrease and Cu (II) an increase of NAD(P)+ reduction. 相似文献
4.
Socorro Durán Luis Sánchez-Linares Alejandro Huerta-Saquero Gisela Du Pont Alejandra Huerta-Zepeda Jorge Calderón 《Biochemical genetics》1996,34(11-12):453-465
We present evidence thatRhizobium etli has two glutaminases differentiated by their thermostability and electrophoretic mobility. The thermostable glutaminase (B) is constitutive, in contrast with the thermolabile glutaminase (A), which is positively regulated by glutamine and negatively regulated by ammonium and by the carbon source. In distinction to glutaminase A, glutaminase B plays a minor role in the utilization of glutamine as a carbon source, but it may play a role in maintaining the balance of glutamine and glutamate. By complementation of theRhizobium etli LM16 mutant that lacks glutaminase A, we have cloned the gene that codes for this enzyme. 相似文献
5.
N. Durán R. V. Antonio M. Haun R. A. Pilli 《World journal of microbiology & biotechnology》1994,10(6):686-690
Radio-isotope studies indicated not only that l-tryptophan can serve as carbon source for synthesis of the trypanocide, violacein by Chromobacterium violaceum (BB-78 strain) but also that isatin and indole 3-acetic acid are both important metabolic intermediates. Using 3-indolyl [2-14C] and [1-14C] acetic acid, it was found that the carboxylic carbon was not eliminated and that indole-3-acetic acid was incorporated intact into the pigment structure. N-Ethyl(5-hydroxy-indol-3-yl)-2-indolylethylamide is also an important metabolic intermediate in the violacein biosynthesis. This is the first report of a metabolic scheme for violacein synthesis which includes an intermediate other than l-tryptophan. 相似文献
6.
Pulmonary insufficiency secondary to outflow tract reconstruction remains an unsolved problem. Although a number of surgical techniques have been designed to avoid or palliate this condition, none so far has been satisfactory. This report describes a new composite stented porcine monocusp patch, which, because of its desirable hemodynamic characteristics, promises to yield stable and reproducible results. The clinical effectiveness of the patch is documented by its successful application in a patient with tetralogy of Fallot. 相似文献
7.
8.
The endotoxin of Bordetella pertussis was cleaved by mild acidic hydrolysis to yield a polysaccharide (polysaccharide I, 15%), a glycolipid (63%) and lipid X (2%). Further treatment of the glycolipid with stronger acid released a second polysaccharide (polysaccharide II, 9%) and material similar to lipid A present in enterobacterial endotoxins. Both polysaccharides possess a single molecule of 3-deoxy-2-octulosonic acid as the reducing, terminal sugar. In polysaccharide II the octulosonic acid is phosphorylated in position 5 and presumably substituted in position 4; in polysaccharide I the octulosonic acid is not phosphorylated, but is substituted in position 5. Following treatment of the endotoxin with strong base, a fragment was isolated that contained bound, non-phosphorylated 3-deoxy-2-octulosonic acid, glucosamine phosphate and fatty acids. This indicated that polysaccharide I, like polysaccharide II, was bound to the lipid region of the endotoxin. The endotoxin structure thus defined is different from that proposed for the lipopolysaccharides of enterobacteria. 相似文献
9.
M Durán-Grande 《Microbiología espa?ola》1974,27(2):103-134
10.
Daniel Silva Torres Bruna Alves de Oliveira Lígia Souza d Silveira Marcos Paulo da Silva Vinícius Rodrigues Durães Pereira Josué Moraes Mara Rúbia Costa Couri Rafaella Fortini Grenfell e Queiroz Patrícia Martins Parreiras Márcio Roberto Silva Lara Azevedo Alves Vinícius Carius de Souza Priscila Vanessa Zabala Capriles Goliatt Eveline Gomes Vasconcelos Ademar Alves da Silva Filho Priscila de Faria Pinto 《化学与生物多样性》2021,18(11):e2100439
In this work, two synthetic aurones revealed moderate schistosomicidal potential in in vitro and in vivo assays. Aurones ( 1 ) and ( 2 ) promoted changes in tegument integrity and motor activity, leading to death of adult Schistosoma mansoni worms in in vitro assays. When administered orally (two doses of 50 mg/kg) in experimentally infected animals, synthetic aurones ( 1 ) and ( 2 ) promoted reductions of 56.20 % and 57.61 % of the parasite load and stimulated the displacement towards the liver of the remaining adult worms. The oogram analysis revealed that the treatment with both aurones interferes with the egg development kinetics in the intestinal tissue. Seeking an action target for compounds ( 1 ) and ( 2 ), the connection with NTPDases enzymes, recognized as important therapeutic targets for S. mansoni, was evaluated. Molecular docking studies have shown promising results. The dataset reveals the anthelmintic character of these compounds, which can be used in the development of new therapies for schistosomiasis. 相似文献