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71.
Bioactive equivalent combinatorial components play a critical role in herbal medicines. However, how to discover and enrich them efficiently is a question for herbal pharmaceuticals researchers. In our work, a novel two‐dimensional reversed‐phase/hydrophilic interaction high‐performance liquid chromatography method was established to perform real‐time components trapping and combining for preparation and isolation of coeluting components. Arenaria kansuensis was taken as an example, and solid‐phase extraction coupled with liquid–liquid extraction as a simple and efficient method for enriching trace components, reversed phase column coupled with hydrophilic interaction liquid chromatography XAmide column as two‐dimensional chromatography technology for isolation and preparation of coeluting constituents, enzyme‐linked immune‐sorbent assay as bio‐guided assay, and anti‐inflammatory bioactivity evaluation for bioactive constituents. A combination of 12 β‐carboline alkaloids was identified as anti‐inflammatory bioactive equivalent combinatorial components from A. kansuensis , which accounts for 1.9% w/w of original A. kansuensis . This work answers the key question of which are real anti‐inflammatory components from A. kansuensis and provides a fast and efficient approach for discovering and enriching trace β‐carboline alkaloids from herbal medicines for the first time. More importantly, the discovery of bioactive equivalent combinatorial components could improve the quality control of herbal products and inspire a herbal medicine based on combinatorial therapeutics.  相似文献   
72.
To fully resolve Theseus' paradox in the framework of the Elementary Process Theory, this paper corrects its formalism and axiomatization.  相似文献   
73.
从物理学基本原理出发,以线圈炮的简单模型为例,导出了计算弹丸所受磁场力的两种表示.证明了它们的等价性,并把结论推广到一般线圈炮的情形.  相似文献   
74.
It is known that a linear ordinary differential equation of order n3 can be transformed to the Laguerre–Forsyth form y (n)= i=3 n a ni (x)y (ni) by a point transformation of variables. The classification of equations of this form in a neighborhood of a regular point up to a contact transformation is given.  相似文献   
75.
Let A be a quasi-hereditary algebra with a strong exact Borel subalgebra. It is proved that for any standard semisimple subalgebra T there exists an exact Borel subalgebra B of A such that T is a maximal semisimple subalgebra of B. It is shown that the maximal length of flags of exact Borel subalgebras of A is the difference of the radium and the rank of Grothendic group of A plus 2. The number of conjugation-classes of exact Borel subalgebras is 1 if and only if A is basic; the number is 2 if and only if A is semisimple. For all other cases, this number is 0 or no less than 3. Furthermore, it is shown that all the exact Borel subalgebras are idempotent-conjugate to each other, that is, for any exact Borel subalgebras B and C of A, there exists an idempotent e of A, and an invertible element u of A, such that eBe = u-1eCeu.  相似文献   
76.
In this paper it is proved that from any uniformly bounded orthonormal system {f n} n=1 of random variables defined on the probability space (Ω, ε, P), one can extract a subsystem {fni} i Emphasis>=1/∞ majorized in distribution by the Rademacher system on [0, 1]. This means that {
}, whereC>0 is independent of m∈N, ai∈N (i=1,…,m) andz>0. Translated fromMatematicheskie Zametki, Vol. 65, No. 4, pp. 483–495, April, 1999.  相似文献   
77.
Let be a locally compact topological groupoid, A and B two C*-algebras endowed with a continuous action of . We define an operator K-theory group K K (A,B). We describe two basic properties of this theory: the existence of a Kasparov product and functoriality with respect to groupoid cocycles.  相似文献   
78.
We show that, for , the relation of -equivalence between infinite sequences of real numbers is Borel reducible to the relation of -equivalence (i.e., the Borel cardinality of the quotient is no larger than that of ), but not vice versa. The Borel reduction is constructed using variants of the triadic Koch snowflake curve; the nonreducibility in the other direction is proved by taking a putative Borel reduction, refining it to a reduction map that is not only continuous but `modular,' and using this nicer map to derive a contradiction.

  相似文献   

79.
Orbits of the ODE y=0 in corresponding jet bundles are investigated. Explicit relations for the right-hand side of an arbitrary 3-order ODE necessary and sufficient for the existence of a contact transformation reducing this equation locally to the form y=0 are obtained.  相似文献   
80.
Dongyuan Yao 《K-Theory》1996,10(3):307-322
Let A be an Abelian category and B be a thick subcategory of A. Let D b(B) denote the derived category of cohomologically bounded chain complexes of objects in A and D B b (A) denote the derived category of cohomologically bounded chain complexes of objects in A with cohomology in B. We give two if and only if conditions for equivalence of D(B) and D B b (A), and we give an example where D b (B) and D B b (A) are not equivalent.  相似文献   
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