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41.
The evaluation of the in vitro cytotoxic properties of two pyrazole compounds: 1-(4-nitrophényl)-3,5-diméthylpyrazole (1) and 1,1'-di(4-nitrophényl)-5,5'-diisopropyl-3,3'-bipyrazole (2) was investigated against Hep cell line (Human laryngeal carcinoma). These two compounds showed an important cytotoxic activity on the Hep cell line, with IC(50): 8.25 microg mL(-1) for the compound 1; IC(50): 10.20 microg mL(-1) for the compound 2 while the IC(50) for adriamycine used as positive control was 3.62 microg mL(-1).  相似文献   
42.
In this work we give sufficient conditions on the semigroup (T 0 (t)) t\geq0 , generated by the part of a Hille—Yosida operator in the closure of its domain, in order that certain perturbations preserve some regularity properties of (T 0 (t)) t\geq0 , like the norm continuity, compactness and differentiability. An application of our abstract results to retarded differential equations is given.  相似文献   
43.
In order to develop relatively small molecules as pharmacologically active molecules, novel 1,4-benzothiazine derivatives with triazole and oxazolidinone were synthesized. In this study, a series of 1,2,3-triazolylmethyl-1,4-benzothiazine derivatives were developed by exploiting a click chemistry reaction using a CuI-catalyzed Huisgen [3 + 2] cycloaddition. Starting from 2-(substituted)-3,4-dihydro-2H-1,4-benzothiazi-3-one, a number of 1,4-benzothiazine derivatives were also synthesized using different alkylating agents to give a 4-(substituted)-2-(substituted)-3,4-dihydro-2H-1,4-benzothiazi-3-one in good yields. The crystal and molecular structure of compound oxazolidin-2-one in basic benzothiazine was established by single-crystal X-ray diffraction. The newly synthesized products were subjected to in vitro biological evaluation. The result indicated that the compounds show convincing antibacterial activities against different microorganisms. All structures of the synthesized compounds were elucidated on the basis of spectral analyses and chemical reactions.  相似文献   
44.

In this work, a terra-cotta brick collected from the famous archaeological Roman city Cuicul, Algeria, was successfully dated by thermoluminescence. The provenance of the fabrication material was also identified by X-ray fluorescence analysis (XRF). The results obtained show that the brick was probably made in 198 A.D. This date is in good agreement with the history of the dated site and the neighborhood Caracalla arch edified in honour to Caracalla emperor (211–217 A.D.). The XRF study demonstrates that the raw clay used for the fabrication of the brick is local and well selected by the Roman builders.

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Posner’s second theorem states that the existence of a nonzero centralizing derivation on a prime ring forces the ring to be commutative. In this paper we extend this result to Jordan ideals of rings with involution. Moreover, some related results are also discussed.  相似文献   
48.
We study the Fredholm properties of parabolic evolution equations on R with inhomogeneous boundary values. These problems are transformed into evolution equations with inhomogeneities taking values in certain extrapolation spaces. Assuming that the underlying homogeneous problem is asymptotically hyperbolic, we show the Fredholm alternative for these equations. The results are applied to parabolic partial differential equations.  相似文献   
49.
We study perturbations at the boundary of linear nonautonomousparabolic boundary value problems. Our approach relies on atransformation of the given inhomogeneous boundary value problemto an evolution equation in larger, time-varying extrapolationspaces. We establish the well-posedness of this equation andDuhamel's formulas relating the evolution families solving theperturbed and the unperturbed problem. By means of these formulas,we can show that the perturbed evolution equation inherits theexponential dichotomy and Fredholm properties of the unperturbedequation if the perturbations are small in norm or compact.This result leads to a Fredholm alternative for the given perturbedboundary value problem.  相似文献   
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