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121.
122.
The dynamic behaviors of cationic liposome-DNA complexes in inside and outside biomembrane models upon lipofection were investigated using the time-resolved quasi-elastic laser scattering (QELS) method. Inside and outside biomembrane models with similar phospholipid compositions to those in living cells were formed at a tetradecane/phosphate buffered saline (TD/PBS) interface. Cationic liposome-DNA complexes were injected into the buffer subphase, and their adsorption/desorption behaviors at the biomembrane models were monitored through changes in the interfacial tension. We found that the adsorption rate of the complexes increased 2.6 times more in the outside model than in the inside one. The adsorption rate of DNA alone did not show a remarkable difference from one side to the other; however, the adsorption rate of the cationic liposome alone showed a similar tendency to that of the liposome-DNA complex. These results indicated that the difference in lipid composition induced a different dynamic behavior of exogenous biomolecules and that the cationic liposomes played an important role in the faster incorporation of DNA into cells upon lipofection. 相似文献
123.
The effect of the Fermi motion on nuclear structure function at largeQ 2 (the EMC effect) is discussed in detail. We especially study its dependences on the kinematics of interaction, the 4-momentum transferQ 2, the nucleon momentum distribution inside nucleus and the nuclear mass number. Moreover the structure function of12C at very largex such asx>1 is evaluated by only the nuclear Fermi motion, and related problems are discussed. We also point out a new dynamical mechanism expected to produce the depletion of valence quark inside nucleus for intermediatex, which does not encroach upon the conventional nuclear physics, and discuss it along the line of scaling hypothesis proposed by Daté et al. 相似文献
124.
125.
126.
Mössbauer measurements on Fe0.068Ni0.932Cl2 were done at temperatures between 55K and 4.2K. We have found that below TN-50K an observed spectrum is composed of two kinds of spectra and that the composition ratio changes gradually with temperature. The average angle of Fe2+ spins, \(\overline {\theta _{Fe} } \) , with the c-axis is smaller than \(\overline {\theta _c } \) by ?15° at each temperature below TN, where \(\overline {\theta _c } \) is the average angle of total spins with the c-axis in this system obtained from the neutron scattering measurements. This is reasonably understood if we take into account that Fe2+ spins have the strong uniaxial anisotropy along the c-axis. We discuss the coexistence of the two kinds of spectra by considering the exchange energy of Fe2+ spins and the local magnetic anisotropy. 相似文献
127.
Kōhei Uchiyama 《Archive for Rational Mechanics and Analysis》1985,90(4):291-311
The paper concerns the asymptotic behavior as
of solutions u(t, x) of the Cauchy problem for the inhomogeneous equation
, x>0, with a mass-preserving boundary condition at x=0. It is assumed that F C
1[0, 1] F(0)=F(1)=0, and that one of the following conditions holds: (i) F has just one zero in (0, 1) and the derivative F is negative at 0 and 1, (ii) F is zero in (0, ) and positive in (, 1) with 0<<1, (iii) F is positive in (0, 1) and c
0
2
>2F(0) (the pushed case). Here c
0 is the minimum of possible speeds of travelling waves for the equation with k(x) replaced by zero. Under a natural restriction imposed on k(x) we prove, for a wide class of initial functions, that u(t, x) approaches w(x + m(t)) as
uniformly in x>0, where w is a travelling wave with the speed c
0 and m is a solution of dm/dt = c
0-k(m). The result has immediate applications to the multidimensional non-linear diffusion equations arising in population genetics, combustion theory, etc. 相似文献
128.
A Cell‐Targeted Non‐Cytotoxic Fluorescent Nanogel Thermometer Created with an Imidazolium‐Containing Cationic Radical Initiator 下载免费PDF全文
Dr. Seiichi Uchiyama Dr. Toshikazu Tsuji Kyoko Kawamoto Dr. Kentaro Okano Eiko Fukatsu Takahiro Noro Kumiko Ikado Sayuri Yamada Yuka Shibata Dr. Teruyuki Hayashi Dr. Noriko Inada Dr. Masaru Kato Dr. Hideki Koizumi Prof. Hidetoshi Tokuyama 《Angewandte Chemie (International ed. in English)》2018,57(19):5413-5417
A cationic fluorescent nanogel thermometer based on thermo‐responsive N‐isopropylacrylamide and environment‐sensitive benzothiadiazole was developed with a new azo compound bearing imidazolium rings as the first cationic radical initiator. This cationic fluorescent nanogel thermometer showed an excellent ability to enter live mammalian cells in a short incubation period (10 min), a high sensitivity to temperature variations in live cells (temperature resolution of 0.02–0.84 °C in the range 20–40 °C), and remarkable non‐cytotoxicity, which permitted ordinary cell proliferation and even differentiation of primary cultured cells. 相似文献
129.
One‐pot Annulation for Biaryl‐fused Monocarba‐closo‐dodecaborate through Aromatic B−H Bond Disconnection 下载免费PDF全文
Gaku Akimoto Mai Otsuka Dr. Kazunori Miyamoto Dr. Atsuya Muranaka Dr. Daisuke Hashizume Dr. Ryo Takita Prof. Dr. Masanobu Uchiyama 《化学:亚洲杂志》2018,13(8):913-917
We have developed a one‐pot annulation reaction of monocarba‐closo‐dodecaborate with cyclic diaryliodonium salts to afford biaryl‐fused derivatives. Aryl functionalities are introduced at both the 1‐carbon and unreactive ortho‐boron vertices of the “σ‐aromatic” carborane cage without the need for pre‐functionalization. DFT calculations revealed that the palladium‐catalyzed C?B bond‐formation step in this process proceeds through a concerted metalation–deprotonation (CMD)‐type pathway for the B?H bond disconnection on the aromatic cage, though such bonds are generally regarded as hydridic. 相似文献
130.
Uchiyama S Ohshima A Nakamura S Hasegawa J Terui N Takayama SJ Yamamoto Y Sambongi Y Kobayashi Y 《Journal of the American Chemical Society》2004,126(45):14684-14685
The complete thermal-unfolding profiles of both oxidized and reduced forms of cytochrome c551 (PA) from mesophilic Pseudomonas aeruginosa and cytochrome c552 (HT) from thermophilic Hydrogenobacter thermophilus were obtained by the newly developed pressure-proof cell compartment installed in a circular dichroic spectrometer, which facilitates protein thermal-unfolding experiments up to 180 degrees C. The thermodynamic cycle, which relates protein stability and redox function, indicated that the redox potentials of PA and HT in the native state are regulated by the stability of the oxidized proteins rather than by that of the reduced ones. 相似文献