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61.
Sudo J Iwase H Higashiyama K Kakuno K Miyasaka F Meguro T Takayama K 《Drug development and industrial pharmacy》2002,28(1):59-65
To increase delivery of L-dopa in its transdermal absorption, a new lipophilic derivative of L-dopa, L-dopa-butylester, was synthesized. An in-vitro study employing two-chamber diffusion cells, in which the excised rat abdominal skin was mounted, revealed that, in the presence of L-menthol and ethanol, L-dopa-butylester penetrated in its original form more effectively than L-dopa. L-Dopa-butylester sheets were made by immersing wiper sheets in methanol containing the compound, and then evaporating the methanol. An extraction study of the compound from the sheets revealed that its stability was maintained for at least 12 weeks. In an in-vivo cutaneous absorption study, an L-dopa-butylester sheet was attached to the shaved rat abdominal skin. A hydrogel containing L-menthol and ethanol was spread on vinyl tape, and this sheet was placed over it. In plasma, the L-dopa level rose linearly between 30 and 180 min after the cutaneous application; L-dopa-butylester was not detected. The L-dopa level was higher than that in which L-dopa was applied. These findings indicated that the lipophilic nature of L-dopa-butylester further increased its penetration through the skin, and that L-dopa-butylester that was taken up into the general circulation system was rapidly converted to L-dopa by hydrolysis in the body. 相似文献
62.
V. A. Shvarts K. J. Kless N. Matsunaga E. D. Adams J. S. Xia E. A. Schuberth 《Journal of Low Temperature Physics》2002,126(1-2):169-178
Simultaneous measurements of magnetic susceptibility from 0.5 to 10 mK and pressure from 2.88 to 3.54 MPa have been made in
3
He nano-clusters embedded in a
4
He matrix, following phase separation. The susceptibility of the 3.54 MPa, all-solid sample behaves similarly to that of bulk
3
He for v=21.3 cm
3
/mole, with a Weiss constant =–250K. For the 2.88 MPa, liquid-droplet sample, =140K, indicating a ferromagnetic tendency, similar to 2-D films at some coverages. At intermediate pressures, has a peak near 1.05 mK, but without a discontinuity. For all samples, had a solid-like contribution to the lowest temperatures. Magnetic ordering in nano-clusters appears to be different than the U2D2 phase of bulk
3
He. 相似文献
63.
Katsuhiko Nakamura Author Vitae Masashi Matsumoto Author Vitae 《Pattern recognition》2005,38(9):1384-1392
This paper describes approaches for machine learning of context free grammars (CFGs) from positive and negative sample strings, which are implemented in Synapse system. The grammatical inference consists of a rule generation by “inductive CYK algorithm,” mechanisms for incremental learning, and search. Inductive CYK algorithm generates minimum production rules required for parsing positive samples, when the bottom-up parsing by CYK algorithm does not succeed. The incremental learning is used not only for synthesizing grammars by giving the system positive strings in the order of their length but also for learning grammars from other similar grammars. Synapse can synthesize fundamental ambiguous and unambiguous CFGs including nontrivial grammars such as the set of strings not of the form ww with w∈{a,b}+. 相似文献
64.
We describe a novel automated flow immunoassay system for quantification of anti-double-stranded (ds) DNA autoimmune antibodies in the serum of patients suffering from systemic lupus erythematosus. dsDNA (360 bp) was covalently coupled with alkaline phosphatase (ALP) to form a novel analytical reagent (ALP-DNA). After immunoreaction, antibody-antigen complexes between ALP-DNA and anti-dsDNA monoclonal antibody were separated from unreacted ALP-DNA by an ion-exchange column on the basis of the difference in isoelectric point. Antibody-antigen complexes were subsequently quantified by luminescence following addition of 3-(2'-spiroadamantane)-4-methoxy-4-(3"-phosphoryloxy)phenyl- 1,2-dioxetane. The assay yielded a linear relationship between signal and concentration of anti-dsDNA monoclonal antibody in the range of 0-300 micrograms/mL. This simple technique permits the assay of anti-dsDNA autoimmune antibodies within 25 min. The ion-exchange column was simply regenerated by occasional elution with eluent (20 mM N-methylpiperazine, pH 5.5) supplemented with 0.5 M NaCl, to remove unreacted ALP-DNA. 相似文献
65.
H Shuto Y Kataoka A Kanaya K Matsunaga M Sueyasu R Oishi 《Canadian Metallurgical Quarterly》1998,341(1):33-37
Patients suffering from inflammatory or dysimmunitary diseases may develop various clinical responses to corticotherapy. This brief article describes the various cellular and molecular mechanisms which underly the genetic, endocrine and immunitary factors involved in corticosensitivity, corticoresistance and corticodependence. 相似文献
66.
Using an XPS technique, the composition and thickness of the surface film and the composition of the underlying alloy surface on Fe-Cr, Fe-Co and Fe-Ni alloys were studied after polishing with silicon carbide paper in trichloro-ethylene and cyclohexane. The compositions of the underlying alloy surface after polishing were almost the same as those of the bulk alloys but the film compositions depended on the alloying addition and environment during polishing. The cationic fractions in the surface films on the Fc-Cr alloys polished in both solvents were almost the same as the corresponding atomic fractions of the bulk alloys. In contrast, iron ions were apt to be concentrated in the surface films on the Fe-Co and Fe-Ni alloys, and the weights of nickel ions were different in the surface films on the Fe-Ni alloys polished in different solvents. Chloride ions were found in the surface films due to the reaction of the metal surface with trichloro-ethylene. The amount of chloride ions was particularly large in the surface films on the Fe-Ni alloys. Heating the alloy specimens under the vacuum of the spectrometer resulted in almost complete reduction of the surface films on the Fe-Co and Fe-Ni alloys, and in the change in the compositions of all alloy surfaces. 相似文献
67.
N. Yamamoto H. Hasimoto S. Matsunaga T. Torigoe 《JOM Journal of the Minerals, Metals and Materials Society》1965,17(7):718-720
Existing procedures are standardized and translated into a computer program. Studies were made of charging, blowing and chemical reactions, and the use of flame radiation pyrometry and two-color pyrometry. 相似文献
68.
69.
The photoionization cross-sections of various deep impurities of interest in solar-grade silicon for photovoltaic cells, and
the corresponding energy levels, have been determined by steady state photo-induced currents in pn junctions or Schottky barrier
junctions irradiated simultaneously with two wavelengths of light. Light of about half the band-gap energy controls the occupancy
of the deep impurity level and the spectral dependence of the photocurrent on a higher photon energy light source then provides,
via the Lucovsky model, the photo-cross-section and the impurity energy level. The results obtained for Au and Pt in Si are
in agreement with those of Braun and Grimmeiss and the energy levels for Fe, Ti, and Ag obtained optically are in agreement
with those obtained by other methods. 相似文献
70.
Matsunaga S Ohshio K Harada E Fujiwara S Uchiyama S Fukui K 《Journal of Bioscience and Bioengineering》2004,98(5):384-386
We applied fluorescent microscopy to monitor the damage of DNA upon exposure to gamma radiation. Our developed dosimetry demonstrated that the number of breaks in DNA is proportional to the dose of the irradiation but is not dependent on dose rate of the irradiation and the GC content of DNA. 相似文献