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231.
232.
Aki H. Koizumi E. Okamoto Y. Yamamoto M. 《Journal of Thermal Analysis and Calorimetry》2001,64(1):293-297
The interactions of benzalkonium chloride (BC)with components of stratum corneum, a model system of intercellular lipids in
human stratum corneum and homogenized rat stratum corneum were characterized in terms of thermodynamics at pH 7.5 and 37°C.
BC was strongly bound to cholesterol and cholesterol sulfate with higher affinities (105~106 M-1) than to any other components of the stratum corneum by hydrophobic interaction and ionic interaction, respectively. BC binding
to the model system of intercellular lipids significantly decreased only in the absence of cholesterol. It is indicated that
cholesterol and its derivatives play an important role in the penetration and/or accumulation of BC in stratum corneum.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
233.
Ishii A Takahashi T Tawata A Furukawa A Oshida H Nakayama J 《Chemical communications (Cambridge, England)》2002,(23):2810-2811
Triptycene-9-thioselenenic acid was synthesized by hydrolysis of acetyl triptycene-9-thioselenenate, the structure of which was determined by spectroscopic data and X-ray diffraction analysis. 相似文献
234.
Waiting time problems for a two-dimensional pattern 总被引:1,自引:1,他引:0
We consider waiting time problems for a two-dimensional pattern in a sequence of i.i.d. random vectors each of whose entries
is 0 or 1. We deal with a two-dimensional pattern with a general shape in the two-dimensional lattice which is generated by
the above sequence of random vectors. A general method for obtaining the exact distribution of the waiting time for the first
occurrence of the pattern in the sequence is presented. The method is an extension of the method of conditional probability
generating functions and it is very suitable for computations with computer algebra systems as well as usual numerical computations.
Computational results applied to computation of exact system reliability are also given.
Department of Statistical Science, School of Mathematical and Physical Science, The Graduate University for Advanced Studies
This research was partially supported by the ISM Cooperative Research Program (2002-ISM-CRP-2007). 相似文献
235.
Sigeo Aki 《Annals of the Institute of Statistical Mathematics》1987,39(1):457-472
Summary This paper is concerned with an extension of the problem of testing symmetry about zero of a distribution function. In order
to obtain the asymptotic null distribution of test statistics for the problem, a limit theorem is proved, which indeed plays
an essential role in the asymptotic theory of testing, problem for symmetry.
The Institute of Statistical Mathematics 相似文献
236.
Waiting Time Problems in a Two-State Markov Chain 总被引:1,自引:0,他引:1
Let F
0 be the event that l
0 0-runs of length k
0 occur and F
1 be the event that l
1 1-runs of length k
1 occur in a two-state Markov chain. In this paper using a combinatorial method and the Markov chain imbedding method, we obtained explicit formulas of the probability generating functions of the sooner and later waiting time between F
0 and F
1 by the non-overlapping, overlapping and "greater than or equal" enumeration scheme. These formulas are convenient for evaluating the distributions of the sooner and later waiting time problems. 相似文献
237.
238.
M. Arisoy O. Temiz-Arpaci F. Kaynak-Onurdag E. Aki I. Yalcin 《SAR and QSAR in environmental research》2013,24(5-6):589-612
In this study, a new series of 2,5-disubstituted benzoxazoles was synthesized and their structures were elucidated by elemental analysis, MASS, 1H-NMR, 13C-NMR and IR spectral data. Newly and previously synthesized 2,5-disubstituted benzoxazole derivatives were evaluated for antibacterial and antifungal activity against standard strains and their drug-resistant isolates. Microbiological results showed that the compounds presented a large spectrum of activity having MIC values of 250–7.8 µg mL?1 against the tested microorganisms. Among the newly synthesized derivatives 3–22, compound 11 was the most active against Candida krusei out of all; however, it was one dilution less potent than standard drug fluconazole. In addition, all the new and previous compounds were more active than standard drugs ampicillin trihydrate and rifampicin against Pseudomonas aeruginosa and its gentamicin-resistant isolate. The 2D-QSAR (Quantitative Structure–Activity Relationship) analysis of a set of newly and previously synthesized benzoxazoles tested for growth inhibitory activity against methicillin-resistant Staphylococcus aureus (MRSA) was also performed by using multivariable regression analysis. The activity contributions for substituent effects of these compounds were determined from the correlation equation for predictions of the lead optimization. 相似文献
239.
Nobuko Mibu Hatsumi Aki Hirohito Ikeda Ai Saito Wataru Uchida Kazumi Yokomizo Jianrong Zhou Takeshi Miyata Kunihiro Sumoto 《Journal of Thermal Analysis and Calorimetry》2013,113(3):1015-1018
Carbohydrate recognition of some bioactive symmetrical tripodal receptor type tris(2-aminoethyl)amine (TAEA) derivatives was investigated. In calorimetric experiments, the highest binding constant (Ka) of compound C (C35H49N5O4S) with methyl α-d-mannopyranoside was Ka = 858 M?1 with 1:1 stoichiometry. Formation of hydrogen bonds in binding between symmetrical tripodal receptor type compound C and sugars was suggested by the large negative values of ?H° (=?34 to ?511 kJ mol?1). In a comparison of each set of α- and β-anomers of some monosaccharides (methyl α/β-d-galactopyranoside, methyl α/β-d-glucopyranoside, and methyl α/β-l-fucopyranoside), compound C showed that the binding constant of β-anomer was larger than that of the corresponding α-anomer, indicating higher β-anomer selectivity. The calculated energy-minimized structure of the complex of compound C with guest methyl α-d-mannopyranoside is also presented. The experimental results obtained from this work indicated that symmetrical tripodal receptor type TAEA derivative C has a lectin-like carbohydrate recognition property. 相似文献
240.