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91.
92.
The generation of a bipolarity solitary wave (soliton) is examined by using a transmission line containing gyromagnetic nonlinear inductors. The results indicate that a transmission line of the form shown here can be used in high-peak-power pulse-generating networks. 相似文献
93.
The evolution of the intelligent network (IN) is summarized, and its service creation requirements and provision environment are clarified. A prototype system called the ISDN development experimental system for advanced services (IDEA), which has been developed to validate the foregoing, is described. The evaluation of the system design and its future evolution are discussed 相似文献
94.
Yukari Totsuka Takashi Higuchi Toshio Imai Akiyoshi Nishikawa Takehiko Nohmi Tatsuya Kato Shuich Masuda Naohide Kinae Kyoko Hiyoshi Sayaka Ogo Masanobu Kawanishi Takashi Yagi Takamichi Ichinose Nobutaka Fukumori Masatoshi Watanabe Takashi Sugimura Keiji Wakabayashi 《Particle and fibre toxicology》2009,6(1):1-11
Background
Recently, manufactured nano/microparticles such as fullerenes (C60), carbon black (CB) and ceramic fiber are being widely used because of their desirable properties in industrial, medical and cosmetic fields. However, there are few data on these particles in mammalian mutagenesis and carcinogenesis. To examine genotoxic effects by C60, CB and kaolin, an in vitro micronuclei (MN) test was conducted with human lung cancer cell line, A549 cells. In addition, DNA damage and mutations were analyzed by in vivo assay systems using male C57BL/6J or gpt delta transgenic mice which were intratracheally instilled with single or multiple doses of 0.2 mg per animal of particles.Results
In in vitro genotoxic analysis, increased MN frequencies were observed in A549 cells treated with C60, CB and kaolin in a dose-dependent manner. These three nano/microparticles also induced DNA damage in the lungs of C57BL/6J mice measured by comet assay. Moreover, single or multiple instillations of C60 and kaolin, increased either or both of gpt and Spi- mutant frequencies in the lungs of gpt delta transgenic mice. Mutation spectra analysis showed transversions were predominant, and more than 60% of the base substitutions occurred at G:C base pairs in the gpt genes. The G:C to C:G transversion was commonly increased by these particle instillations.Conclusion
Manufactured nano/microparticles, CB, C60 and kaolin, were shown to be genotoxic in in vitro and in vivo assay systems. 相似文献95.
Akinobu Takaki Tetsuya Yasunaka Takahito Yagi 《International journal of molecular sciences》2015,16(8):17494-17513
Hepatitis B often progresses to decompensated liver cirrhosis requiring orthotopic liver transplantation (OLT). Although newer nucleos(t)ide analogues result in >90% viral and hepatitis activity control, severely decompensated patients still need OLT because of drug-resistant virus, acute exacerbation, or hepatocellular carcinoma. Acute hepatitis B is also an indication for OLT, because it can progress to fatal acute liver failure. After OLT, the hepatitis B recurrence rate is >80% without prevention, while >90% of transplant recipients are clinically controlled with combined hepatitis B immunoglobulin (HBIG) and nucleos(t)ide analogue treatment. However, long-term HBIG administration is associated with several unresolved issues, including limited availability and extremely high cost; therefore, several treatment protocols with low-dose HBIG, combined with nucleos(t)ide analogues, have been investigated. Another approach is to induce self-producing anti-hepatitis B virus (HBV) antibodies using an HBV envelope (HBs) antigen vaccine. Patients who are not HBV carriers, such as those with acutely infected liver failure, are good candidates for vaccination. For chronic HBV carrier liver cirrhosis patients, a successful vaccine response can only be achieved in selected patients, such as those treated with experimentally reduced immunosuppression protocols. The present protocol for post-OLT HBV control and the future prospects of newer treatment strategies are reviewed. 相似文献
96.
We propose a ray-tracing model that provides a clear physical picture and simple formulas for grating pair stretcher dispersion calculations. With this model we can easily demonstrate why and to what extent the stretcher and compressor are opposite quantitatively without using a Fourier transform. The dispersion calculation shows that the spherical aberration in the stretcher decreases fourth-order dispersion compared with an aberration-free stretcher. In a chirped pulse amplification system, this fourth order can help to reduce residual fourth-order dispersion. The effect of the finite beam size and the misalignment are also considered. 相似文献
97.
Infrared spectroscopy was applied to identify and determine microamounts of anionic surfactants contained in sewage or river waters. The surfactants tested were linear alkylbenzene sulfonate (LAS), branched alkylbenzene sulfonate (ABS), alpha olefine sulfonate (AOS), fatty alcohol sulfate (AS) and fatty alcohol ethoxy sulfate (AES).Anionic surfactants in waters were extracted by chloroform as methylene blue complexes and sulfate type surfactants, i.e. AS and AES were then removed by subsequent hydrolysis. Residual sulfonate type surfactants were first released from methylene blue complexes by ion exchange technique and then changed to sulfonyl chloride derivatives for infrared spectroscopy. Key bands for the identification of sulfonate type surfactants are 640, 618 and 524 cm−1 for LAS, ABS and AOS, respectively. Sulfate type surfactants was calculated from the difference of methylene blue active substance contents before and after hydrolysis. 相似文献
98.
I Pontén JM Sayer AS Pilcher H Yagi S Kumar DM Jerina A Dipple 《Canadian Metallurgical Quarterly》1999,38(3):1144-1152
Diastereomeric N6-substituted dAdo adducts (cis B[c]PhDE-2/1R and cis B[c]PhDE-2/1S) that correspond to cis-opening at C-1 of the enantiomeric benzo[c]phenanthrene 3,4-diol 1,2-epoxides in which the epoxide oxygen and the benzylic hydroxyl group are trans (DE-2) were synthetically incorporated into oligonucleotide 16-mers. Each adduct was placed at the fourth nucleotide from the 5'-end of each of two different oligonucleotide sequences derived from the E. coli supF gene. Each adduct was also placed in two additional oligonucleotide sequences that were constructed by interchanging the adduct site and the immediately adjacent nucleotides between the two original sequences. These oligonucleotides were designed for use in site-specific mutation studies, with a single-stranded bacteriophage M13mp7L2 vector, to determine if the effects of sequence context on types and frequencies of base substitution mutations are attributable only to nucleotides immediately adjacent to these polycyclic aromatic hydrocarbon diol epoxide-dAdo adducts, or whether more distant nucleotide residues also affect the mutagenic response. In SOS-induced Escherichia coli SMH77, total base substitution mutation frequencies for the cis B[c]PhDE-2/1R-dAdo adduct were relatively low (0.62-5.6%) compared with those for the cis B[c]PhDE-2/1S-dAdo adduct (11.9-56.5%). Depending on sequence context, cis B[c]PhDE-2/1R-dAdo gave predominantly A-->T or a more equal distribution of A-->T and A-->G mutations whereas cis B[c]PhDE-2/1S-dAdo gave either predominantly A-->T or predominantly A-->G base substitutions. Our results clearly indicate that nucleotides that are distal as well as those that are proximal to the adduct site are capable of influencing both the mutation frequency and the distribution of base substitution mutations. 相似文献
99.
By using the characteristics of a hydrogen-absorbing alloy, the hydrogen produced by catalytic dehydrogenation of saturated
compounds can be absorbed to form metal hydrides, and, vice versa, the resulting metal hydrides are able to hydrogenate efficiently
unsaturated compounds upon dehydriding. Gas-phase reactions between 2-butene and 2-propanol on a hydrogen-absorbing alloy
CaNi5 have been studied in the temperature range of 393–473 K. CaNi5 showed interesting characteristics as an active catalyst for the catalytic transfer hydrogenation of butene from propanol
as a hydrogen donor. 2-propanol was effectively dehydrogenated at 423 K to yield acetone in which the dissociated hydrogen
was completely absorbed by CaNi5 to form the metal hydride. When the alloy was hydrided to some extent, butene was hydrogenated by the absorbed hydrogen in
the metal hydride to produce butane. The overall reaction on CaNi5 was expressed as catalytic transfer hydrogenation of 2-butene from 2-propanol through intermediate formation of metal hydrides,
rather than the direct reaction between butene and propanol on the alloy. Thus, CaNi5 effectively repeated hydriding–dehydriding cycles: hydriding of CaNi5 by 2-propanol dehydrogenation with subsequent dehydriding for the hydrogenation of 2-butene. The use of hydrogen-absorbing
CaNi5 provides a novel reaction system for the catalytic transfer hydrogenation.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
100.