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831.
The transmissivity and the optical absorption of a WO3 film with oxygen deficiencies introduced were characterized and compared with those of an electrochromically colored WO3 upon injecting a proton (H+). The WO3 film with oxygen deficiencies introduced was clearly colored blue. It was shown that the wavelength regions of optical absorption of both films almost overlapped each other. 相似文献
832.
833.
Saleta Vazquez‐Rodriguez Miranda Wright Catherine M. Rogers Adam P. Cribbs Srikannathasan Velupillai Martin Philpott Henry Lee James E. Dunford Kilian V. M. Huber Matthew B. Robers James D. Vasta Marie‐Laetitia Thezenas Sarah Bonham Benedikt Kessler James Bennett Oleg Fedorov Florence Raynaud Adam Donovan Julian Blagg Vassilios Bavetsias Udo Oppermann Chas Bountra Akane Kawamura Paul E. Brennan 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(2):525-529
834.
Ryo Murakami Daisuke Sekine Yuma Aoki Shintaro Kawamura Mikiko Sodeoka 《Tetrahedron》2019,75(10):1327-1335
We present a tetrahydrocarbozole-forming carbo-trifluoromethylation of indoles bearing an alkenyl group at the C3 position. The reaction proceeded selectively with the combination of TsOH·H2O as a catalyst and CH2Cl2 as a solvent. The site-selectivity could be altered by changing the reaction solvent; the use of THF instead of CH2Cl2 increased the formation of aromatic trifluoromethylation products. 相似文献
835.
A nucleophilic addition reaction to N-methylaldimines without acid or metal species is described. A novel reagent, dicyanomethyl acetate, is used as a nucleophile to give alpha-(N-methyl-N-acetyl)amino acid methyl esters in excellent yield. 相似文献
836.
Uremic toxins are accumulated in the blood of patients with chronic renal failure (CRF), although alteration of the toxicity by the interaction of various uremic retention products has not been precisely clarified. In this study, we found that cytochrome c added to incubation mixtures containing guanidino compounds and methylglyoxal in phosphate buffer solution (pH 7.4) resulted in reduction of cytochrome c. Superoxide anions were generated from incubation mixtures of each guanidino compound with methylglyoxal, because the reduction was inhibited by the addition of superoxide dismutase. The incubation mixture containing each guanidino compound and methylglyoxal had different rates of generation of the superoxide anion from other mixtures. A relatively higher superoxide anion formation rate was observed in the incubation mixture containing Arg and methylglyoxal (7.9 +/- 0.5nmol x m(-1) x min(-1)), or in the incubation mixture containing methylguanidine and methylglyoxal (6.3 +/- 0.6 nmol x ml(-1) min(-1)). These findings suggest that interactions of various uremic retention products which accumulate in the blood of uremic patients may generate reactive oxygen species and may be involved in the oxidative stress observed in CRF patients. The addition of aminoguanidine, which is known to inhibit the formation of advanced glycation end products, to a mixture of guanidino compounds and methylglyoxal inhibited reactions between guanidino compounds and methylglyoxal. 相似文献
837.
A rapid and precise method for the determination of barium in bone is presented. Barium as the nitrate is directly separated from calcium by co-precipitation with added strontium using fuming nitric acid. Atomic absorption measurements are made at 553.6 nm using a nitrous oxide-acetylene flame in the presence of strontium and potassium, and being free from noise due to the emission of CaOH. In order to improve accuracy and speed a radioactive tracer is used. 相似文献
838.
S Oshiro Y Yajima K Kawamura M Kubota J Yokofujita Y Nishibe M Takahama H Nakajima 《Chemical & pharmaceutical bulletin》1992,40(7):1847-1851
After internalization of hemoglobin-haptoglobin complex (Hb-Hp) via receptor-mediated endocytosis (RME) into liver parenchymal cells, organelles containing the complex distribute in the microsome fraction (Ms). Prior to the catabolism, Hb-Hp dissociates symmetrically into two 82,000-dalton (82 kDa) subunits. In the present investigation, the first event of Hb-Hp metabolism in Ms were further examined after [3H-heme, 14C-glogin]Hb-Ho or [125I-Hb]Hp injection to rats. Shortly after the internalization of Hb-Hp, this complex in Ms was intact. At 60 min after injection, radioactive materials of Ms extracted by freezing and thawing (F&T) with yield of 15% were composed of Hb-Hp, 82 kilodaltons (kDa) subunits and Hb metabolites with a ratio of 1:6:13. The heme metabolites were identified as [3H]bilirubin by high performance liquid chromatography (HPLC). The ratio of Hb-Hp/82 kDa subunits/Hb metabolites in microsome residue of the F&T was 40:8:1. The radioactivity in Ms at 60 min localized microsomes subfraction except Golgi light fraction. In electron microscope radioautography of microsome subfraction using [125I]Hb-Hp, silver grains were observed over or within morphologically heterogenous vesicles, e.g. vesicles containing very low density lipoprotein (VLDL) particles with appendage like multi-vesicular body (MVB) or compartment of uncoupling of receptor and ligand (CURL) in Goligi light and intermediate fractions. These studies suggest that Hb-Hp internalized by RME is dissociated symmetrically into two 82 kDa subunits in organelles of Ms, and that organelles with MVB or CURL-like structures are associated with Hb-Hp metabolism. 相似文献
839.
S Iguchi H Iwamura M Nishizaki A Hayashi K Senokuchi K Kobayashi K Sakaki K Hachiya Y Ichioka M Kawamura 《Chemical & pharmaceutical bulletin》1992,40(6):1462-1469
A novel, highly cardioselective ultra short-acting beta-blocker, ONO-1101, has been developed for application in the emergency treatment of tachycardia and better control of heart rate in surgery. This agent is approximately nine times more potent in beta-blocking activity in vivo and eight times more cardioselective in vitro than esmolol. This beta-blocking drug has a short duration of activity, enabling rapid recovery after cessation of administration if side effects occur. It can be used safely in patients suffering from acute heart disease and represents a major therapeutic advance in the treatment of heart disease. 相似文献
840.
The magnetic circular dichroism spectra of the halogen molecules I2, Br2 and Cl2 were investigated in solutions. The spectral region studied was 800-250 nm. The MCD spectra were interpreted successfully in terms of the transitions to the states 1u(3II) and 1II. The major result is the resolution of the overlapping contributions from O+u(3II) and 1II. 相似文献