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251.
DNA结合蛋白结构域的研究进展* 总被引:2,自引:0,他引:2
本文综述了3种DNA结合蛋白结构域-螺旋一转折一螺旋、亮氨酸拉链、锌指近年来的研究进展。参考文献65篇。 相似文献
252.
本文研究了有界星形圆型域上α次生映照,给出其增长定理,所讨论的域是最广泛的,若域不是星形的,则其上不存在星形映照。 相似文献
253.
作者得到有界星形圆型域上的α次强星形映照的增长这理,所讨论的域是相当广泛的,因为非有界星形圆形域上可能不存在星形映照。 相似文献
254.
In this paper, the unique solvability of oblique derivative boundary value problems for second order nonlinear equations of mixed (elliptic-hyperbolic) type in multiply connected domains is proved, which mainly is based on the representation of solutions for the above boundary value problem, and the uniqueness and existence of solutions of the above problem for the equation uxx + sgn y uyy = 0. 相似文献
255.
We report on the analysis of additional X‐ray reflections that probably arise from antiphase domain boundaries within (Ga,In)P/(001) GaAs heteroepitaxial layers. Due to the preferred cation ordering along the crystallographic directions [1‐1 1] and [‐1 1 1] which belong to the [110] zone the original sphalerite‐type structure of (Ga,In)P changes into a CuPt‐like of the cation sublattice. This ordering phenomenon causes a loss of symmetry, i.e. the cubic structure is converted into a rhombohedral one. The antiphase boundaries between ordered domains are assumed to behave similar to lattice planes at X‐ray diffraction. Therefore, additional reflections may occur spatially neighboured to the [001] direction. The presented results of X‐ray experiments are discussed in relation to TEM experiments published in the literature in order to explain the origin of the satellite reflections. In the case of the investigated samples (grown on GaAs substrates misoriented 2° towards the azimuthal [010] direction) the APBs run preferentially in directions tilted up to angles of 20° with respect to growth direction. A preferential occurrence of satellite reflections in <13 2 1> directions was observed coinciding with {13 2 1} "lattice planes" whose normals enclose the same angle to the [001] growth direction as the normals of the average planes characterized by APBs. The appearence of the phenomenon in other directions that are also spatially neighboured to the <13 2 1> directions was determined on the basis of the shift of the reflection positions due to tilting the sample around an axis geometrically included in the scattering plane. 相似文献
256.
本文主要研究C~n中有界凸Reinhardt域B_p上正规化双全纯完全准凸映射的齐次展开式问题,设f(z):B_p→C~n(p>2)是一个正规化双全纯完全准凸映射,k是满足k<p≤k+1的自然数,那么f_j(z)=z_j+α_(j2)z_j~2+…+α_(jk)z_j~k+O(|z|~(K+1)),其中f_j是f的第j个分量,j=1,2….,n. 相似文献
257.
Sascha Orlik 《Advances in Mathematics》2008,219(2):728-741
We determine the fundamental group of period domains over finite fields. This answers a question of M. Rapoport raised in [M. Rapoport, Period domains over finite and local fields, in: Proc. Sympos. Pure Math., vol. 62, part 1, 1997, pp. 361-381]. 相似文献
258.
Biomembranes consist of a lipid bi-layer into which proteins are embedded to fulfill numerous tasks in localized regions of
the membrane. Often, the proteins have to reach these regions by simple diffusion. Motivated by the observation that IP3 receptor channels (IP3R) form clusters on the surface of the endoplasmic reticulum (ER) during ATP-induced calcium release, the reaction rate of
small diffusing molecules on a cylindrical membrane is calculated based on the Smoluchowski approach. In this way, the cylindrical
topology of the tubular ER is explicitly taken into account. The problem can be reduced to the solution of the diffusion equation
on a finite cylindrical surface containing a small absorbing hole. The solution is constructed by matching appropriate ‘inner’
and ‘outer’ asymptotic expansions. The asymptotic results are compared with those from numerical simulations and excellent
agreement is obtained. For realistic parameter sets, we find reaction rates in the range of experimentally measured clustering
rates of IP3R. This supports the idea that clusters are formed by a purely diffusion limited process. 相似文献
259.
Given separable Banach spaces X, Y, Z and a bounded linear operator T:X→Y, then T is said to preserve a copy of Z provided that there exists a closed linear subspace E of X isomorphic to Z and such that the restriction of T to E is an into isomorphism. It is proved that every operator on C([0,1]) which preserves a copy of an asymptotic ℓ1 space also preserves a copy of C([0,1]). 相似文献
260.