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51.
52.
Transient absorption spectra of adenine, adenosine and 2'-deoxyadenosine 5'-monophosphate (dAMP) arising from 248 nm laser flash photolysis using acetone as a photosensitizer have been observed. The intermediates recorded are assigned to the excited triplet states and dehydrogenated radicals of adenine and its nucleoside and nucleotide. The excited triplet states of adenine and its derivatives are produced via triplet-triplet excitation transfer and observed for the first time, while the dehydrogenated radicals stemming from the interaction of triplet acetone with adenine and its derivatives via electron transfer through a five-member-ring electron donor-acceptor intermediate. The site of dehydrogenation is suggested to be the hydrogen atom on C(8) of the adenine moiety. Moreover, three sets of kinetic parameters of the triplet decay have been determined. The rate constants of the unimolecular decay (k0), the triplet quenching by the ground state (ksq) and by the triplet quencher Mn2+ (kq) are 1.1 x 10(5), 7.9 x 10(4), 3.7 x 10(4) s-1, 6.9 x 10(8), 8.3 x 10(8), 3.6 x 10(8) dm3 mol-1 s-1 and 4.2 x 10(8), 3.5 x 10(8), 6.0 x 10(8) dm3 mol-1 s-1 respectively for adenine, adenosine and dAMP. 相似文献
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D Allasia C Angelini A Baldini L Bertanza V Bisi F Bobisut T Bolognese A Borg E Calimani P Capiluppi S Ciampolillo J Derkaoui ML Faccini-Turluer R Fantechi V Flaminio AG Frodesen D Gamba G Giacomelli H Huzita B Jongejans M Loreti C Louedec G Mandrioli A Margiotta A Marzari-Chiesa R Pazzi L Ramello L Riccati A Romero AM Rossi A Sconza P Serra-Lugaresi A Tenner Van Apeldoorn GW Van Dam P D Vignaud R Wigmans 《Canadian Metallurgical Quarterly》1985,31(11):2996-2998
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We report here an experience with five patients, aged 58 to 70, suffering gangrene of the left colon after spontaneous inferior mesenteric artery occlusion. All cases were the result of arteriosclerosis; in two, small aortic aneurysms were present and might have been responsible for emboli to the inferior mesenteric artery. The dead bowel was resected in all patients; three patients survived. No primary anastomoses were done and they are not recommended. Because ligation of the patent inferior mesenteric artery has been done so often without ill effects during aortic surgery, the collateral circulation to the left colon can be considered excellent. Gangrene is therefore rare and requires major interference with collateral circulation by emboli or arteriosclerotic occlusion. The clinical symptoms and signs may be confusing. 相似文献
57.
A Bizzi E Veneroni MT Tacconi AM Codegoni R Pagani M Cini S Garattini 《Canadian Metallurgical Quarterly》1980,5(3-4):227-240
Liquipron and Toprina, obtained by growing yeasts (Candida maltosa and Candida lipolytica) on n-hydrocarbons, were investigated to ascertain the biological significance and possible toxicological implications of their high content of uneven fatty acids (UFA). It was confirmed that the extent to which UFA accumulate in adipose tissue of rats fed the 2 products reflects only partially their UFA contents. The presence of UFA in rat tissues does not appear to alter intermediate metabolism. The capacity of liver mitochondria ot oxidize palmitic acid was similar in control and in Liquipron-treated rats. Palmitic acid and heptadecanoic acid did not compete for oxidation when mixed at concentrations which reflect their presence in the tissues of animals fed high levels of Liquipron. 相似文献
58.
A commercially available recording of Northwestern University Auditory Test No. 6 (N.U. No. 6) produced by Auditec of St. Louis was evaluated in a series of four studies. Interlist equivalence of this version was initially investigated, and then normative intelligibility functions were developed using listerners with normal hearing. Intelligibility functions for the original version of N.U. No. 6. prepared by Northwestern University, were then derived, concurrently with functions of the Auditec version, using (1) a group of listeners with normal hearing; and (2) a group with sensorineural hearing loss. The results demonstrated good interlist equivalence for the Auditec version of N.U. No. 6. The comparative intelligibility functions for the Auditec and Northwestern versions of N.U. No 6 furthermore indicated a difference between the two recordings, but it was concluded that for clinical purposes the two versions may be considered equivalent. 相似文献
59.
Cognitive performance in conversion hysteria 总被引:1,自引:0,他引:1
In order to test some neurobiologically based assumptions pertaining to attention and memory dysfunction in conversion hysteria, a series of tasks was given to 17 hospitalized patients with hysterical conversion reaction and to a control group of nonpsychotic patients under conditions of nonstress and stress. The results indicated significant differences in performance between hysteria and control subjects. The former group, in comparison to controls, had heightened suggestibility, greater field dependency, and greater impairment of recent memory and vigilance-attention. A discriminant analysis indicated the feasibility of using such tests as objective diagnostic criteria for hysteria. 相似文献
60.
In order to evaluate the preventive value of specific immune serum globulin against hepatitis type B, we have used this immune globulin in required doses in 12 patients (10 with AU antigen negative and 2 with AU antigen positive) with chronic renal failure who required maintenance hemodialysis for a period of 15 months, and we were able to prevent hepatitis type B in our dialysis patients. 相似文献