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161.
Mesoporous γ‐Iron Oxide Nanoparticles for Magnetically Triggered Release of Doxorubicin and Hyperthermia Treatment 下载免费PDF全文
Dr. Farah Benyettou Jaen Alonso Ocadiz Flores Dr. Florent Ravaux Dr. Rachid Rezgui Dr. Mustapha Jouiad Samer I. Nehme Rajesh Kumar Parsapur Prof. John‐Carl Olsen Prof. Parasuraman Selvam Prof. Ali Trabolsi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(47):17020-17028
Mesoporous iron‐oxide nanoparticles (mNPs) were prepared by using a modified nanocasting approach with mesoporous carbon as a hard template. mNPs were first loaded with doxorubicin (Dox), an anticancer drug, and then coated with the thermosensitive polymer Pluronic F108 to prevent the leakage of Dox molecules from the pores that would otherwise occur under physiological conditions. The Dox‐loaded, Pluronic F108‐coated system (Dox@F108‐mNPs) was stable at room temperature and physiological pH and released its Dox cargo slowly under acidic conditions or in a sudden burst with magnetic heating. No significant toxicity was observed in vitro when Dox@F108‐mNPs were incubated with noncancerous cells, a result consistent with the minimal internalization of the particles that occurs with normal cells. On the other hand, the drug‐loaded particles significantly reduced the viability of cervical cancer cells (HeLa, IC50=0.70 μm ), wild‐type ovarian cancer cells (A2780, IC50=0.50 μm ) and Dox‐resistant ovarian cancer cells (A2780/AD, IC50=0.53 μm ). In addition, the treatment of HeLa cells with both Dox@F108‐mNPs and subsequent alternating magnetic‐field‐induced hyperthermia was significantly more effective at reducing cell viability than either Dox or Dox@F108‐mNP treatment alone. Thus, Dox@F108‐mNPs constitute a novel soft/hard hybrid nanocarrier system that is highly stable under physiological conditions, temperature‐responsive, and has chemo‐ and thermotherapeutic modes of action. 相似文献
162.
163.
Spectral Analysis and Generation Results for Streaming Operators with Multiplying Boundary Conditions 总被引:2,自引:0,他引:2
This paper deals with the spectral theory of streaming equations for smooth or partly smooth boundary operators. Generation results for muliplying boundary operators in L
1-spaces are also given. 相似文献
164.
Michel P. Crozet Mustapha Kaafarani Wallid Kassar Jean-Marie Surzur 《Tetrahedron letters》1982,23(48):5039-5042
Several β-aminothiols prepared from 3-piperideine and different thiiranes react by free radical reactio chemically initiated to yield exclusively 7-thia-1-azabicyclo (4,3,0) nonane derivatives. Even when this process is in competition with a radical addition on a terminal ethylenic chain, the bicyclic thiazolidine is always the major product. 相似文献
165.
Mustapha Bouhadef 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1978,29(1):157-167
Résumé Quand un jet liquide cylindrique vertical tombe sur une plaque plane horizontale, il s'étale en général sur celle-ci en un écoulement en film mince limité par un ressaut circulaire, au delà duquel, le film a une épaisseur plus grande. Une étude théorique est faite aussi bien en zone torrentielle qu'en zone fluviale et la position du ressaut est déterminée; ces résultats sont comparés aux courbes expérimentales et l'évolution du profil des vitesses est déterminée dans la zone fluviale par anémométrie laser.
Cette recherche a fait l'objet d'un contrat ONRS (Organisme National de la Recherche Scientifique Algérien) No. 76 AA 01/1. 相似文献
Conclusion Cette étude nous a permis de mettre en évidence une concordance acceptable entre le profil réel et le profil semi-parabolique des vitesses dans la zone fluviale dans le cas de nos conditions expérimentales [11]. D'autres conditions, ne permettant pas le renouvellement constant du liquide de la surface libre, auraient conduit certainement à un autre type de profil [12]. Par ailleurs le calcul théorique associé à ce profil nous a permis de prévoir la position du ressaut avec une précision acceptable. Enfin, la structure du ressaut relatif à ce type d'écoulement a pu être précisée.When a cylindrical vertical liquid jet falls on an horizontal flat plate it spreads out generally in a thin layer bounded by a circular hydraulic jump outside which the layer has a much greater depth. The theoretical study is done for the supercritical and subcritical flows and the hydraulic jump is located. The relations obtained are compared with experimental results and the evolution of the velocity profil is determined in the subcritical flow by laser anemometry.
Cette recherche a fait l'objet d'un contrat ONRS (Organisme National de la Recherche Scientifique Algérien) No. 76 AA 01/1. 相似文献
166.
A. O. Mustapha N. O. A. Oladipo S. B. Elegba 《Journal of Radioanalytical and Nuclear Chemistry》1994,181(2):343-350
The mean squared slowing-down distance, <r
2>, and the age to themal capture (Migration Area),M
2, are direct measures of the slowing-down, and the spreading out, processes of neutrons in a medium. They also enter directly into reactor calculations. These parameters have been determined experimentally for Am-Be neutrons (mean energy 4.46 Me V), in a block of perpex, using the activities induced in thin indium foils from the115In(n,)116In reactions. 相似文献
167.
For C a bounded, injective operator with dense image, we define a C-regularized spectral distribution. This produces a functional calculus, f f(B), from C() into the space of closed densely defined operators, such that f(B)C is bounded when f has compact support. As an analogue of Stone's theorem, we characterize certain regularized spectral distributions as corresponding to generators of polynomially bounded C-regularized groups. We represent the regularized spectral distribution in terms of the regularized group and in terms of the C-resolvent. Applications include the Schrödinger equation with potential, and symmetric hyperbolic systems, all on Lp(n) (1p<), C
o(n), BUC(n), or any space of functions where translation is a bounded strongly continuous group. 相似文献
168.
Hossni Ziyat My Youssef Ait Itto Mustapha Ait Ali Abdellah Karim Abdelkhalek Riahi Jean‐Claude Daran 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):o90-o93
The two new gem‐dihalogenocyclopropanes (1′S,3R)‐3‐(2′,2′‐dichloro‐1′‐methylcyclopropyl)‐6‐oxoheptanoic acid, C11H16Cl2O3, (2), and (1′S,3R)‐3‐(2′,2′‐dibromo‐1′‐methylcyclopropyl)‐6‐oxoheptanoic acid, C11H16Br2O3, (3), are isostructural. Both present two stereogenic centers at C1′ and C3. The absolute configuration was determined by X‐ray methods. The cyclopropyl rings are unsymmetrical, the shortest bond being distal with respect to the alkyl‐substituted C atom. 相似文献
169.
Mustapha Azreg-A?nou 《Monatshefte für Chemie / Chemical Monthly》2005,57(1):2017-2027
We investigated empirical data for the vapor pressure (154≤T≤196 K) and the heat capacity (12.52≤T≤189.78 K) of solid carbon dioxide. A computer algebra system (CAS) was used for all calculations. From the numerical point of view, we have adopted a cubic piecewise polynomial representation
for the heat capacity and reached an excellent agreement between the available empirical data and the calculated ones. Furthermore,
we have obtained values for the vapor pressure and heat of sublimation at temperatures below 195 right down to 0 K. The theoretical
key prerequisites are: 1) Determination of the heat of sublimation of 26250 J · mol−1 at vanishing temperature and 2) Elaboration of a ‘linearized’ vapor pressure equation that includes all the relevant properties
of the gaseous and solid phases. It is shown that: 1) The empirical vapor pressure equation derived by Giauque & Egan remains valid below the assumed lower limit of 154 K (a similar argument holds for Antoine’s equation), 2) The heat of sublimation reaches its maximum value of 27211 J · mol−1 at 58.829 K and 3) The vapor behaves as a (polyatomic) ideal gas even for temperatures below 150 K. 相似文献
170.
A structural study of amphiphilic PAMAM (poly(amido amine)) dendrimers in Langmuir and Langmuir-Blodgett films 总被引:2,自引:0,他引:2
Sui G Mabrouki M Ma Y Micic M Leblanc RM 《Journal of colloid and interface science》2002,250(2):364-370
Two amphiphilic PAMAM dendrimers are synthesized by attaching 12-hydroxydodecanoic acid (HA) chains to a poly(amido amine) (PAMAM) dendrimer core (including generation I and generation II). The limiting molecular area obtained from the surface pressure-area isotherm at the air/water interface suggests the edge-on configuration for both dendrimers in Langmuir films. The edge-on arrangement is also supported by the atomic force microscopic (AFM) studies of the Langmuir-Blodgett films. 相似文献