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131.
The near infrared (NIR) absorption was investigated on the glucose aqueous solutions with various optical pathlengths (PLs) and processed by ultrasonic cavitation. In water, the strong absorption peak at a wavelength of 1430 nm, appeared in the case of short PL, was separated into several peaks in the case of wide PL due to increasing the number of H(2)O clusters. In a d(+) glucose solution, it was seen that NIR absorption was reduced at peculiar wavelengths of 970 nm and 1130 nm and its profile changed in a capricious manner in the region from 1300 nm to 1600 nm. The cavitation generated lots of OH(-) ion in water and made the capricious absorption profile regularly graded with the cavitation time toward less-absorptive direction. These effects are supposed to be caused by the dipole moments of H(2)O clusters arranged by the interaction between them and generated basic OH ions. The statistical principal component regression (PCR) and partial least-squares (PLS) regression demonstrated that the treatment of UC was helpful to enhance the glucose sensitivity. 相似文献
132.
133.
Reaction of a series of (E)-3-phenyl-4-(p-substituted phenyl)-3-buten-2-ones with p-sulfamylphenyl hydrazine in glacial acetic acid gave the corresponding hydrazones, subsequent treatment of which with 30% HCl afforded pyrazole-1-sulphonamides. On the other hand, refluxing of chalcones with either thiosemicarbazide or isonicotinic acid hydrazide in ethanol containing a few drops of acetic acid gave pyrazoline-1-thiocarboxamides and isonicotinoyl pyrazolines, respectively. The structures of the synthesized compounds were determined on the basis of their elemental analyses and spectroscopic data. The antimicrobial activity of the newly isolated heterocyclic compounds was evaluated against Gram-positive, Gram-negative bacteria and fungi. Most of the compounds showed a moderate degree of potent antimicrobial activity. 相似文献
134.
Takuya Yokosaka Akinari Hamajima Tetsuhiro Nemoto Yasumasa Hamada 《Tetrahedron letters》2012,53(10):1245-1248
We developed a novel method for the asymmetric synthesis of highly functionalized γ-lactams through an organocatalytic aza-Michael–Michael reaction cascade using fumaric acid amide esters as multi-reactive substrates. Using chiral primary or secondary amine organocatalysts, we obtained two types of γ-lactams with three contiguous chiral centers in moderate to good yield with excellent enantioselectivity and diastereoselectivity. 相似文献
135.
Diethyl phosphorocyanidate (DEPC) can be efficiently used for the synthesis of α-amino nitriles from carbonyl compounds and amines. The reaction may be called a modified Strecker synthesis. 相似文献
136.
Yoshitaka Ishimuro Fumiyuki Hamada Akio Nakajima 《Journal of polymer science. Part A, Polymer chemistry》1979,17(6):1811-1819
The scattering function of rods with a constant radius, 8 Å, and a length distribution of the Schulz–Zimm type was calculated on a computer as a model of helical synthetic polypeptide. The influence of length and length distribution on the scattered intensity of small-angle x-ray scattering was clarified. As length grows and length distribution broadens it is difficult to obtain reliable values of molecular weight and radius of gyration from a Zimm plot. The influence of length distribution on the mass per unit length, Mq, and the radius of gyration of the cross section, 〈S〉1/2, from the Guinier plot of the cross-sectional factor decreases as the length increases, and reliable values of Mq and 〈S〉1/2 can be obtained even for rods with wide distribution for rods more than 600 Å long. In particular, it is pointed out that the value of 〈S〉1/2 is little influenced by length and length distribution. 相似文献
137.
A sensitive assay for acyl CoA-cholesterol acyltransferase (EC 2.3.1.26) in rat liver microsomal and mitochondrial preparations is described. The lowered cholesterol concentration in the enzyme reaction with oleoyl CoA is determined spectrofluorimetrically by using the cholesterol oxidase/peroxidase/p-hydroxyphenylpropionic acid system. The assay requires as little as 20 μg of protein in the enzyme preparation. 相似文献
138.
Hirofumi Okuda Shigeru Matsushima Hideshi Sugiura Kenji Yamada Shunsuke Hamada Yoshihiro Nishida Naoki Ishiguro 《Magnetic resonance imaging》2014
Objective
Equivalent cross-relaxation rate imaging (ECRI) is an MRI technique used to evaluate qualitative changes in protein-water interactions. We aimed to prospectively evaluate the utility of ECRI for classification of adipocytic tumors.Materials and Methods
Institutional Review Board approval was obtained and all patients provided informed consent. Study participants included 40 patients with adipocytic tumors who were diagnosed with lipomas (n = 22), atypical lipomatous tissue/well-differentiated liposarcoma (ALT/WDL; n = 9), myxoid/round cell liposarcoma (MyL; n = 6), and dedifferentiated liposarcoma (DDL; n = 3), and 20 control patients for whom subcutaneous fat in the buttock or thigh was analyzed.Results
Mean ECR values of lipomas, ALT/WDL, and subcutaneous fat were low, and those of MyL and DDL were high. Mean ECR values of MyL and DDL were significantly higher than those of ALT/WDL. The cut-off value was 5.1%. There was a positive correlation between ECR value, pathological grade, and cell density in adipocytic tumors.Conclusion
The ECR value positively correlates with pathological grade and cell density of adipocytic tumors. Our findings suggest that ECRI is a useful method for preoperative evaluation of adipocytic tumors. 相似文献139.
140.
Yoshiaki Hamada Kazuko Hashiguchi Masamichi Tsuboi Yoshinori Koga Shigeo Kondo 《Journal of Molecular Spectroscopy》1984,105(1):70-80
Methyleneimine was detected in the gas phase by a moderately high resolution infrared spectrometer as one of the intermediate species produced by a pyrolysis of amines. Observed vibrational frequencies of some isotopic derivatives have been combined with the ab initio values to reach a most reliable force constants set. Some other spectroscopic parameters, involving geometrical parameters and dipole moment derivatives, have also been calculated ab initio and compared with the observation. Its half-life in our experimental apparatus was about 10 min, which is much longer than the previously reported values, 0.1 or 10 sec. 相似文献