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71.
Enzyme immunoassay of somatostatin (SS)-like immunoreactive substance in bovine milk 总被引:1,自引:0,他引:1
M Takeyama N Yanaga K Yarimizu J Ono R Takaki N Fujii H Yajima 《Chemical & pharmaceutical bulletin》1990,38(2):456-459
A sensitive and specific enzyme immunoassay (EIA) for somatostatin (SS)-like immunoreactivity (SS-LI) was developed with the use of beta-D-galactosidase labeled antigen. The minimum amount of SS-like immunoreactive substance (SS-IS) detectable by this method was 1.0 fmol/well (25 pmol/l). The level of SS-IS in bovine foremilk was about 20 pmol/l, and the level was unchanged after delivery. On the other hand, the levels of gastrin releasing peptide (GRP)-IS and vasoactive intestinal polypeptide (VIP)-IS in bovine foremilk were very high, but fell during 1 week after delivery to about 10% of those in foremilk. 相似文献
72.
73.
The ruthenium(III) complex bearing phenylpyridine as a cyclometalated ligand serves as an efficient catalyst for the aerobic oxidative dehydrogenation of benzylamines to the corresponding benzonitriles under mild conditions. 相似文献
74.
Yoshimune Nonomura Takaharu Fujii Yuichiro Arashi Taku Miura Takashi Maeno Kaoru Tashiro Yasuhisa Kamikawa Rie Monchi 《Colloids and surfaces. B, Biointerfaces》2009,69(2):1-267
Water has a unique touch as well as characteristic physical properties. However, nobody knows the real identity of its touch. Here, we show that water creates a stick-slip feel when a small amount is rubbed using fingertip on an artificial skin that mimics the structure of human skin. The results of frictional analyses predict that this stick-slip feel is caused by a drastic change in frictional resistance. The present result is valuable for biologists and robot engineers as well as cognitive scientists and tribologists, because it is a new example of stick-slip phenomena on biological surfaces. The tactile texture of this most familiar material could also be applied to consumer products or virtual reality systems. 相似文献
75.
Takaki Hayashi Nakahiro Yoshida 《Annals of the Institute of Statistical Mathematics》2008,60(2):367-406
We consider the problem of estimating the covariance of two diffusion-type processes when they are observed only at discrete
times in a nonsynchronous manner. In our previous work in 2003, we proposed a new estimator which is free of any ‘synchronization’
processing of the original data and showed that it is consistent for the true covariance of the processes as the observation
interval shrinks to zero; Hayashi and Yoshida (Bernoulli, 11, 359–379, 2005). This paper is its sequel. Specifically, it establishes asymptotic normality of the estimator in a general nonsynchronous sampling scheme. 相似文献
76.
Eiji Hashimoto Yuichi Seshimo Keita Sasanuma Yuichiro Aoki Hitoshi Kanazawa Yuji Ike Seiji Kojima 《Journal of Thermal Analysis and Calorimetry》2010,99(1):45-50
The fragility of ethylene glycol and glucose aqueous solution systems has been investigated by temperature-modulated differential
scanning calorimetry (TMDSC). The frequency and temperature dependences of complex specific heat have been observed in the
vicinity of a glass-transition temperature T
g
. It is shown that the value of the fragility index m can be determined from the temperature dependence of the α-relaxation times observed by TMDSC. We have also studied the elastic
properties of these aqueous solutions by micro-Brillouin scattering, and determined these relaxation times of elastic properties
in the gigahertz range. 相似文献
77.
RuS2 nanoparticles, smaller than 3 nm in diameter, were prepared by H2S gas injection into the AOT/isooctane reverse micellar solution containing RuCl3 aqueous solution. The nanoparticle size was found to be independent of the Wo (water content) value of the reverse micellar system, as shown by TEM observation. The recovery and immobilization of the RuS2 nanoparticles from reverse micelles onto thiol-modified polystyrene particles (PSt-SH) were successfully carried out, by the addition of PSt-SH into the reverse micellar solution under conditions of mild stirring. The resulting composites, PSt-RuS2, showed photocatalytic activity for H2 generation form aqueous solution containing 2-propanol and Na2SO3 as sacrificial electron donors. 相似文献
78.
An asymptotic distribution theory of the nonsynchronous covariation process for continuous semimartingales is presented. Two continuous semimartingales are sampled at stopping times in a nonsynchronous manner. Those sampling times possibly depend on the history of the stochastic processes and themselves. The nonsynchronous covariation process converges to the usual quadratic covariation of the semimartingales as the maximum size of the sampling intervals tends to zero. We deal with the case where the limiting variation process of the normalized approximation error is random and prove the convergence to mixed normality, or convergence to a conditional Gaussian martingale. A class of consistent estimators for the asymptotic variation process based on kernels is proposed, which will be useful for statistical applications to high-frequency data analysis in finance. As an illustrative example, a Poisson sampling scheme with random change point is discussed. 相似文献
79.
We have shown from in situ synchrotron x-ray diffraction measurements that there are two thermodynamically stable liquid forms of SnI(4), depending on the pressure. Based on the liquid-liquid critical point scenario, our recent measurements suggest that the second critical point, if it exists, may be located in a region close to the point at which the melting curve of the crystalline phase abruptly breaks. This region is, unlike that of water, experimentally accessible with relative ease. 相似文献
80.
We have developed gel sheet-supported C(2)C(12) myotube micropatterns and combined them with a microelectrode array chip to afford a skeletal muscle cell-based bioassay system. Myotube line patterns cultured on a glass substrate were transferred with 100% efficiency to the surface of fibrin gel sheets. The contractile behavior of each myotube line pattern on the gel was individually controlled by localized electrical stimulation using microelectrode arrays that had been previously modified with electropolymerized poly(3,4-ethylenedioxythiophene) (PEDOT). We successfully demonstrated fluorescent imaging of the contraction-induced translocation of the glucose transporter, GLUT4, from intracellular vesicles to the plasma membrane of the myotubes. This device is applicable for the bioassay of contraction-induced metabolic alterations in a skeletal muscle cell. 相似文献