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101.
Ozaki Shoichiro Kong Xiang-Zheng Watanabe Yutaka Hoshiko Tomonori Ogasawara Tomio Ueno Takao Furukawa Uiroyuki Iigo Masaaki Hoshi Akio 《中国化学》1998,16(2):171-177
In order to get good antitumor agents especially better than 5-fluorouracil, tegafur and l-hexylcarbamoyl-5-fluorouracil (HCFU), fourty nine 1-carbamoyl-5-fluorouracil having aromatic ring were synthesized from 5-fluorouracil and isocyanates or mines. Antitumor activity was tested in the L1210 tumor system, and 5 compounds gave better value of therapeutic ratio than 5-fluorouracil, tegafur, HCFU. 1-(4-Methoxybenzylcarbamoyl)-5-fluorouracil gave the best result. 相似文献
102.
Toichiro A. Katsumi Katsuo Aizawa Yukari Kuroiwa Kouichi Saito Yasushi Kurata Yoshiteru Li Tetsuya Okunaka Chimori Konaka Harubumi Kato 《Photochemistry and photobiology》1996,64(4):671-675
Abstract— The authors performed photodynamic therapy (PDT), avoiding any hyperthermic effects, using a newly developed diode laser and photosensitizer, mono-L-aspar-tyl chlorin e6 (NPe6), of Meth-A fibrosarcoma implanted in mice and achieved tumor therapeutic benefit. The photodynamic light treatment was performed 5 h following the photosensitizer administration. With 5.0 mg/kg NPe6 and light doses of 50, 100, 150 and 200 J/cm2 , the tumor cure rates were 20, 50, 70 and 90%, respectively. With 100 J/cm2 laser exposure and NPe6 doses of 1.25, 2.5, 5.0, 7.5 and 10.0 mg/kg, the tumor cure rates were 0, 20, 50, 70 and 90%, respectively. A charge-coupled device (CCD) camera system was employed to measure the NPe6 fluorescence intensity correlating with the residual amount of the photosensitizer at deferent depth from the tumor surface. The ratios of the NPe6 fluorescence intensity at 3 mm from the tumor surface following 50, 100, 150 and 200 J/cm2 laser exposure to no laser exposure were 0.73, 0.36, 0.22 and 0.16, respectively. With samples sectioned at 1 mm depth, after 50 J/cm2 and the same photosensitizer dose (5 mg/kg) this ratio was 0.19. These results suggest that a certain increase in the tumor tissue level of NPe6 and a certain increase of laser light dose reaching deeper layers of tumor caused an increase in percent cure. In addition, the effectiveness of PDT depends on the total laser dose reaching deeper layers of tumors. Furthermore, the effectiveness of PDT tends to correlate with the amount of NPe6 photobleaching by PDT. 相似文献
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104.
The high-resolution emission spectra measured using a microscope Raman spectrometer and direct-inlet electron ionization mass spectrometry (DI-EIMS) were studied for the rapid analysis of a trace amount of various europium beta-diketonates in order to utilize them as fluorescent markers. Five kinds of europium beta-diketonates were distinguished from the emission spectra obtained using the Raman spectrometer. For DI-EIMS, the electron ionization mass spectra of the europium beta-diketonates showed the characteristic fragment ion peaks due to the isotope effect of 151Eu and 153Eu. The DI-EIMS was very useful for identifying the compounds compared with spectrofluorometry. The scan and selected ion-monitoring modes of DI-EIMS showed the detection limits of the samples at levels of hundreds and tens of nanograms (ng), respectively. 相似文献
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108.
G. E. F. Lundell A. P. Ford A. A. Blair Isaburo Wada Shoichiro Saito I. Musatti M. Croce G. Tomarchio A. W. Beshgetoot Luis Hurtado Acera W. F. Pond L. Sacerdoti und J. E. Clenell 《Fresenius' Journal of Analytical Chemistry》1930,81(8-9):316-323
Ohne Zusammenfassung 相似文献
109.
Yamada H Kurata M Tanabe K Ito T Nishimoto S 《Organic & biomolecular chemistry》2012,10(10):2035-2043
We have designed and synthesized DNA duplexes containing 5-dimethylaminocytosine ((DMA)C) to investigate the effects of C(5)-substituted cytosine bases on the transfer and trapping of positive charge (holes) in DNA duplexes. Fluorescence quenching experiments revealed that a (DMA)C base is more readily one-electron oxidized into a radical cation intermediate as compared with other natural nucleobases. Upon photoirradiation of the duplexes containing (DMA)C, the photosensitizer-injected hole migrated through the DNA bases and was trapped efficiently at the (DMA)C sites, where an enhanced oxidative strand cleavage occurred by hot piperidine treatment. The (DMA)C radical cation formed by hole transfer may undergo specific hydration and subsequent addition of molecular oxygen, thereby leading to its decomposition followed by a predominant strand cleavage at the (DMA)C site. This remarkable property suggests that the modified cytosine (DMA)C can function as an efficient hole-trapping site in the positive-charge transfer in DNA duplexes. 相似文献
110.
A large-mode-area all-solid photonic bandgap fiber with a seven-cell core and five high-index rod rings is investigated. Numerical simulations show that an effective area of more than 500 μm(2), a bending loss of less than 0.1 dB/m at a bending radius of 10 cm and effectively single-mode operation can be achieved simultaneously. A core diameter of 44.8 μm and an effective area of 650 μm(2) at 1064 nm are achieved in a fabricated fiber. Bending loss at 1064 nm is 0.09 dB/m at a bending radius of 7 cm. Effectively single-mode operation is also realized at a bending radius of 10 cm. 相似文献