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991.
Kun Wang Marie Camman Gervaise Mosser Bernard Haye La Trichet Thibaud Coradin 《Molecules (Basel, Switzerland)》2022,27(7)
Fibrin-Type I collagen composite gels have been widely studied as biomaterials, in which both networks are usually formed simultaneously at a neutral pH. Here, we describe a new protocol in which mixed concentrated solutions of collagen and fibrinogen were first incubated at acidic pH to induce fibrinogen gel formation, followed by a pH change to neutral inducing collagen fiber formation. Thrombin was then added to form fibrin-collagen networks. Using this protocol, mixed gels containing 20 mg.mL−1 fibrin and up to 10 mg.mL−1 collagen could be prepared. Macroscopic observations evidenced that increasing the content of collagen increases the turbidity of the gels and decreases their shrinkage during the fibrinogen-to-fibrin conversion. The presence of collagen had a minor influence on the rheological properties of the gels. Electron microscopy allowed for observation of collagen fibers within the fibrin network. 2D cultures of C2C12 myoblasts on mixed gels revealed that the presence of collagen favors proliferation and local alignment of the cells. However, it interferes with cell differentiation and myotube formation, suggesting that further control of in-gel collagen self-assembly is required to elaborate fully functional biomaterials. 相似文献
992.
S. S. Gorelik Z. A. Zarifyants L. S. Milevskii T. B. Sagalova 《Crystal Research and Technology》1981,16(2):255-257
Thermostability of polycrystalline films and their structure changes have been investigated in dependence on the fast electron irradiation. It was shown that the type of the radiation defects depends on the irradiation. temperature. The temperature of the recrystallization process is shown to decrease from 1300°C in the case without irradiation down to 1000°C in the case of recrystallization when irradiating. 相似文献
993.
Yu. S. Boyarskaya J. Schreiber D. Z. Grabko M. P. Dyntu B. M. Pushkash 《Crystal Research and Technology》1981,16(8):965-970
The (111) plane of MgO single crystals was deformed by a concentrated load. It was observed that the number of rows of a cathodoluminescence rosette is a factor of two lower than that for the etch pit one. The explanation of this phenomenon is given. The polarity of plastic deformation was revealed using both an etch pit technique and cathodoluminescence method. It is shown that deformation causes a change of the cathodoluminescence spectra. The spectra, obtained from crystal deformed by indentation and from compressed crystal, are similar. 相似文献
994.
J. Auleytner J. Bak Z. Furmanik M. Maciaszek A. Saulewicz 《Crystal Research and Technology》1980,15(3):301-304
In this paper the X-ray section topograph method was used for determination of damaged layer thickness of silicon crystal surface. For measurements such reflections should be chosen for which the “margine” effect is very sharp. It was used the fact that in the ranges of strong perturbances the approximation of kinematic theory could be applied. 相似文献
995.
N. A. Bert M. Z. Zhingarev S. G. Konnikov N. M. Mursakulov D. N. Tretyakov 《Crystal Research and Technology》1980,15(7):787-793
The results of investigations concerning the peculiarities of obtaining InAs—InAs1−xSbx heterostructure and of its properties revealed that the quality of epitaxial layers as well as photoelectric and electroluminescent device structure characteristics are to a great extent determined by a disagreement magnitude of heterostructure materials. — To decrease the magnitude of disagreement at the layer-substrate boundary and to achieve the composition with x > 0.1 at some distance the method of layer-by-layer growth (ANDREWS et al.) and the obtaining a graded heterojunction with optimization of component distribution along epilayer thickness seems to be promising. 相似文献
996.
Raluca Pele Gabriel Marc Anca Stana Ioana Ionu Cristina Nastas Brîndua Tiperciuc Ilioara Oniga Adrian Pîrnu Laurian Vlase Ovidiu Oniga 《Molecules (Basel, Switzerland)》2022,27(8)
Considering the important damage caused by the reactive oxygen (ROS) and nitrogen (RNS) species in the human organism, the need for new therapeutic agents, with superior efficacy to the known natural and synthetic antioxidants, is crucial. Quinazolin-4-ones are known for their wide range of biological activities, and phenolic compounds display an important antioxidant effect. Linking the two active pharmacophores may lead to an increase of the antioxidant activity. Therefore, we synthesized four series of new hybrid molecules bearing the quinazolin-4-one and phenol scaffolds. Their antioxidant potential was evaluated in vitro, considering different possible mechanisms of action: hydrogen atom transfer, ability to donate electrons and metal ions chelation. Theoretical quantum and thermodynamical calculations were also performed. Some compounds, especially the ortho diphenolic ones, exerted a stronger antioxidant effect than ascorbic acid and Trolox. 相似文献
997.
Ya. Z. Darbaidze S. M. Esakia V. R. Garsevanishvili Z. R. Menteshashvili 《Fortschritte der Physik》1980,28(10):501-525
The deep inelastic scattering of electrons (muons) and neutrinos on the nuclei and the process of lepton pair production in hadron-nucleus collisions are considered. The expressions for the corresponding differential cross-sections are derived provided the final lepton and the spectator fragment of the initial nucleus are detected in coincidence. The structure functions of the processes under consideration are analysed by the principle of automodelity. Some scale-invariant regularities are established for them. In the framework of “light front” formalism for many-body systems the relations of these structure functions to the usual structure functions of the deep inelastic lepton hadron interaction are obtained. A hypothesis is put forward on the scale invariance of structure functions with respect to the ξ-variable which is some complicated dimensionless combination of kinematic invariants. 相似文献
998.
999.
Jos Mahía Miguel A. Maestro Miguel Vzquez Manuel R. Bermejo Ana M. Gonzlez Marcelino Maneiro 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(3):347-348
The structure of the title compound, C30H30N4O4S2, is highly conditioned in the solid state by two strong N—H?N interactions. The values of the distances between the aminic N atoms [5.865 (3) Å] and the iminic N atoms [2.930 (4) Å], in conjunction with the long distance between the S atoms of the two tosyl groups [7.673 (1) Å], suggest that when the molecule acts as a ligand it will provide a single cavity for N4 coordination to the metal centre. 相似文献
1000.
J. Xing Z. -C. Tan Q. Shi B. Tong S. -X. Wang Y. -S. Li 《Journal of Thermal Analysis and Calorimetry》2008,92(2):375-380
Three different nitrocellulose (NC) samples produced from linters were investigated. DSC studies on the NC+sym-diethyldiphenylurea (C1) mixtures were carried out. The influence of storage time on their pore structures was examined using
thermoporometry. The results led to conclusion that large pores are multiples of small ones. The parameter n was used to characterize the number of C1 molecules equivalent to NC ring. Its value for short storage time was about 9 but
for longer time reached the value of 3. The influence of thermal history on the phase transition and porosity of the different
nitrocellulose samples was different. 相似文献