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11.
Noboru Matsumura Motoyuki Kusamiya Hiroo Inoue Masanori Yasui Fujiko Iwasaki 《Journal of heterocyclic chemistry》1995,32(4):1269-1275
1,3-Bis(p-substituted-phenylthiocarbamoyl)-2-imidazolidinethiones 3a-f reacted with bromine to give trithiadiazapentalene derivatives 5a-f , bearing the exocyclic C-N double bonds, in moderate yields. The molecular structure of 5b was elucidated by the X-ray crystallographic analysis. The treatment of 5b-f with hydrochloric acid gave the ring-opening products, 1,3-bis(p-substituted-phenylthiocarbamoyl)-2-imidazo-lidinones 9b-f , accompanied by the production of elemental sulfur. Reduction of 5b , 5d , and 5e with sodium borohydride gave the ring-opening compounds, 1,3-bis(p-substituted-phenylthiocarbamoyl)-2-imidazolidines 13b , 13d , and 13e respectively. 相似文献
12.
Nanosized TiO2 supported on activated alumina was prepared using a sonochemical method. To prepare this supported material, direct immersion horn and cup horn ultrasonic systems were used. The efficiency of the sonochemical coating process was determined by UV photodecolourisation of the aqueous methyl orange solution. It was found that TiO2 supported on activated alumina prepared by the sonochemical method gave the maximum decolourisation efficiency. In that method itself, direct immersion horn gave a higher photodecolourisation activity as compared to the cup horn. The obtained results suggest that the direct immersion horn results in uniform, as well as a maximum number of TiO2 particles to be adsorbed on an activated alumina surface. 相似文献
13.
M Mitsukuchi J Nakagami T Ikemoto S Higuchi Y Tarumoto H Yasui K Sota 《Chemical & pharmaceutical bulletin》1989,37(6):1534-1539
A series of 17-succinyl derivatives of four corticosteroids was prepared. They were tested for vasoconstrictive activity in humans, using 9 alpha-fluoro-11 beta, 21-dihydroxy-16 beta-methyl-17 alpha-valeryloxy-1,4-pregnadiene-3,20-dione (betamethasone 17-valerate, BV) as a standard. The activities of the 21-chloro 17-methylsuccinate compounds (6A, 6C and 6D) were greater than that of BV. A structure-activity relationship study showed that the activities of the 21-chloro 17-methylsuccinates were more potent than those of the corresponding 21-esters. 相似文献
14.
Inumaru K Kasahara T Yasui M Yamanaka S 《Chemical communications (Cambridge, England)》2005,(16):2131-2133
Well-crystallised TiO2 particles (P-25, 20-30 nm in diameter) were directly incorporated into surfactant-templated mesoporous silica particles (pore diameter: 2.7 nm), and the composite material with a high TiO2 content (60 wt%) showed molecular selective and enhanced photocatalysis for decomposition of 4-nonylphenol. 相似文献
15.
Relative bone mineral content in the lumbar spine was measured by phantom B-MAs with the apparatus of computerized tomography in order to study the relationships between bone mineral content with age and parathyroid hormone in sera of randomized out- and in-patients and the hemodialysis patients. There exists a significant difference between male and female in the loss of bone mineral content of three groups. 相似文献
16.
F Oka H Sagawa K Yabe A Okuyama M Tachibana T Noge K Torizumi S Okamoto M Yasui T Tuda 《Radioisotopes》1988,37(10):572-575
The patients receiving maintenance hemodialysis were divided into two groups in the absence and the presence of bone pain and investigated the markers of bone pain in these patients. These results suggested that the duration of receiving hemodialysis, serum concentrations of alkaline phosphatase, osteocalcin and parathyroid hormone became to be the markers of bone pain. 相似文献
17.
The clinical significance of osteocalcin in sera of bone tumors were measured in sera of various kinds of bone tumors. The levels of osteocalcin were higher in bone tumors than those in normal subjects. Serum osteocalcin levels in hypercalcemic groups of bone metastasis and myeloma showed a remarkable increase in a parallelism with serum ALP and LDH levels. These results suggested to be directly or indirectly activated on osteoblast by bone tumors and to be synthesized osteocalcin in osteoblast. 相似文献
18.
Single-bubble sonochemiluminescence in aqueous luminol solutions 总被引:1,自引:0,他引:1
Hatanaka S Mitome H Yasui K Hayashi S 《Journal of the American Chemical Society》2002,124(35):10250-10251
Sonochemiluminescence (SCL) of luminol due to a single bubble is studied through spectral measurement. No SCL was observed from a stable single bubble that emitted high-intensity sonoluminescence (SL). In contrast, SCL was observed under conditions of an unstable dancing bubble, where a bubble grows and ejects tiny bubbles, making it "dance" by counteraction. Furthermore, SCL was observed from dancing bubbles even when SL was not observed, depending on the dissolved gas content. The instability of bubble collapse is the key parameter governing SCL. 相似文献
19.
Performance of six quinolylazo compounds was studied as a pre-column derivatizing reagent for the separation of metal ions in the reversed-phase high-performance liquid chromatography. 2-(4-Methyl-2-quinolylazo)-5-diethylaminophenol (QADP) was suited for the determination of Co, Ni and Cu in the presence of a large amount of Fe. The detection limits under the optimized conditions [stationary phase: L-column ODS; mobile phase: acetone-water (62:38, v/v) containing 0.01 M NH(4)SCN and 0.01 M 2-morpholinoethanesulfonic acid-NaOH (pH 6); injection volume: 10 mul] were 0.24 ng for Co, 0.22 for Ni and 0.53 for Cu. This method was successfully applied to the determination of these metal ions in a standard steel sample. 相似文献
20.
Application of radiolabeled monoclonal anti-tumor antibodies for diagnosis and therapy has made remarkable progress in the past few years. Quantification of radiopharmaceutical localization is required adequate attenuation correction in SPECT imaging. Attenuation correction by transmission CT (TCT) data is one of the best method at present time. However, if a patient is moved between TCT and SPECT, this method is no more applicable. We developed a new attenuation correction algorithm by dual energy method, using 99mTc and 111In because of similarity of these linear attenuation coefficients. The new algorithm uses data of TCT with an external source of 99mTc, and requires another data from SPECT of 111In labeled monoclonal anti-tumor antibody, which are simultaneously obtained. TCT results in an attenuation map, which then serves as input into the final intrinsic correction algorithm to uncorrected SPECT data. In chest phantom experiment, the attenuation corrected SPECT images revealed nearly same distribution of actual radioactivity of 111In as compared to that of uncorrected one. 相似文献