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181.
Grainger Reid J. Ko Samuel Koslov Eugene Prokop Ales Tanner Robert D. Loha Veara 《Applied biochemistry and biotechnology》2000,84(1-9):761-768
Human insulin in zinc suspension was used as a model protein to test the effect of shear on the settling rate of proteins,
a possible inference for protein denaturation. The rate of settling was determined directly in a spectropho-tometer. Shear
effects are important in retaining the activity of proteins and are present in bubble, foam, and droplet protein fractionation
processes. A sim pletest, such as that conducted here, mayeven be useful for monitoring changes in protein structure caused
by commercial shipping of the protein. The settling ratefor insulin was continously monitored in theoriginal bottle by spectrophotometric
absorbance changes as a function of time. A settling curve was determined following each shear experiment, which included
shaking the “worked” insulin solution in a vortex mixer for different lengths of time. It was determined, when comparing long
shaking times with short ones, that the initial settling rate was less for the long-term shaking of the insulin samples and
greater for the short-term shaking. The secondary effects of light and heat, along with shaking, a pparently did not produce
differences from shaking alone. 相似文献
182.
183.
Wonlyul Ko 《Nonlinear Analysis: Theory, Methods & Applications》2009,71(9):4185-4202
In this paper, a diffusive two-competing-prey and one-predator system with Beddington-DeAngelis functional response is considered. The sufficient and necessary conditions for the existence of coexistence states are provided using the fixed point index theory developed. In addition, the stability and uniqueness of coexistence states are investigated. Finally, this paper discusses the sufficient conditions for extinction and permanence of the time-dependent system. 相似文献
184.
Summary The aim of our study was to monitor Cyclosporine A (CA) during a long-term period and to determine whether the whole-blood
levels, estimated by HPLC and radio-immunoassay (RIA), provide a relevant indicator of the toxic effect of CA, of the interference
of endogenous substances with CA and of interactions of erythromycin and ketoconazole with CA metabolims. The ratios of CA
concentrations, estimated by RIA and by HPLC were calculated in order to analyse changes in CA metabolism. A decrease in this
ratio was observed in these patients during periods of erythromycin and ketoconazole therapy deteriorating hepatic function.
We observed unusual higher CA concentrations measured by HPLC compared with RIA in heart transplant patient with marked renal
insiffuciency after one-year follow-up period of treatment of CA. The comparison of CA whole-blood levels estimated using
HPLC and RIA makes it possible to analyse the individual biotransformation of CA to its metabolites, and interference of endogenous
substance in special clinical situations. 相似文献
185.
186.
Muhammet Tamer Koşan 《Proceedings Mathematical Sciences》2009,119(4):453-458
Let R be a commutative Noetherian ring with non-zero identity and a be a maximal ideal of R. An R-module M is called minimax if there is a finitely generated submodule N of M such that M/N is Artinian. Over a Gorenstein local ring R of finite Krull dimension, we proved that the Socle of H
a
n
(R) is a minimax R-module for each n ≥ 0. 相似文献
187.
We prove that any mapping class on a compact oriented surface with non-empty boundary can be made pseudo-Anosov and right-veering
after a sequence of positive stabilizations.
相似文献
188.
Z. KoŽíšek 《Czechoslovak Journal of Physics》1989,39(6):585-592
The problem of the transient time in nucleation is studied. The size-dependent transient time at a constant temperature is defined and the approximate analytical solution is found and compared with the exact numerical solution for the model Li2O.2 SiO2 melt. It is shown that the analytical solution for the size-dependent transient time is in agreement with the numerical result. 相似文献
189.
Nadeem ur Rehman Öznur Gölbaşı Emine Koç 《Rendiconti del Circolo Matematico di Palermo》1938,62(2):245-251
Let \((R,*)\) be a \(2\)-torsion free \(*\)-prime ring with involution \(*\), \(L\ne \{0\}\) be a \(*\)-Lie ideal of \(R\). An additive mapping \(d:R\rightarrow R\) is called an \((\alpha ,\beta )\)-derivation of \(R\) such that \(d(xy)=d(x)\alpha (y)+\beta (x)d(y)\). In the present paper, we shall show that when \(L\) satisfies any of several identities involving \(d\), then \(L\) is central. 相似文献
190.
A crystal distribution function is established during the crystallization process of simple glass-forming melts on the basis of the numerical computation of the kinetic equation in a non-stationary regime for constant and non-constant temperature. Nucleation rate and time-temperature-transformation curves are determined from the calculations of the crystal distribution function at various constant temperatures for various parameters of the system (the dependence on the difference of the chemical potentials, the dependence on the surface energy etc.). 相似文献