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51.
Uptake of 3H-cAMP by retinal pigment epithelium isolated from bluegill sunfish (Lepomis macrochirus)
Background
Metabotropic glutamate receptors (mGluRs) regulate neuronal excitability and synaptic strength. The group I mGluRs, mGluR1 and 5, are widespread in the brain and localize to post-synaptic sites. The Homer protein family regulates group I mGluR function and distribution. Constitutively expressed 'long' Homer proteins (Homer 1b, 1c, 2 and 3) induce dendritic localization of group I mGluRs and receptor clustering, either internally or on the plasma membrane. Short Homer proteins (Homer 1a, Ania-3) exhibit regulated expression and act as dominant negatives, producing effects on mGluR distribution and function that oppose those of the long Homer proteins. 相似文献52.
We use Adomian decomposition method for solving the fractional nonlinear two-point boundary value problemwhere D is Caputo fractional derivative, c is a constant, μ > 0, and F:[0,1]×[0,∞)→[0,∞) a continuous function. The fractional Bratu problem is solved as an illustrative example. 相似文献
53.
Joshi HM Bhumkar DR Joshi K Pokharkar V Sastry M 《Langmuir : the ACS journal of surfaces and colloids》2006,22(1):300-305
Nanomaterials have gained tremendous importance in biology and medicine because they can be used as carriers for delivering small molecules such as drugs, proteins, and genes. We report herein the binding of the hormone insulin to gold nanoparticles and its application in transmucosal delivery for the therapeutic treatment of diabetes mellitus. Insulin was loaded onto bare gold nanoparticles and aspartic acid-capped gold nanoparticles and delivered in diabetic Wistar rats by both oral and intranasal (transmucosal) routes. Our principle observations are that there is a significant reduction of blood glucose levels (postprandial hyperglycemia) when insulin is delivered using gold nanoparticles as carriers by the transmucosal route in diabetic rats. Furthermore, control of postprandial hyperglycemia by the intranasal delivery protocol is comparable to that achieved using the standard subcutaneous administration used for type I diabetes mellitus, thus showing considerable promise for further development. 相似文献
54.
Digna Varghese V. Arun P. P. Robinson Manju Sebastian P. Leeju G. Varsha K. K. M. Yusuff 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(12):o612-o614
The Schiff base compounds N,N′‐bis[(E)‐quinoxalin‐2‐ylmethylidene]propane‐1,3‐diamine, C21H18N6, (I), and N,N′‐bis[(E)‐quinoxalin‐2‐ylmethylidene]butane‐1,4‐diamine, C22H20N6, (II), crystallize in the monoclinic crystal system. These molecules have crystallographically imposed symmetry. Compound (I) is located on a crystallographic twofold axis and (II) is located on an inversion centre. The molecular conformations of these crystal structures are stabilized by aromatic π–π stacking interactions. 相似文献
55.
Varsha Daftardar-Gejji Hossein Jafari 《Journal of Mathematical Analysis and Applications》2005,301(2):508-518
Adomian decomposition method has been employed to obtain solutions of a system of fractional differential equations. Convergence of the method has been discussed with some illustrative examples. In particular, for the initial value problem:
56.
Varsha Daftardar-Gejji 《General Relativity and Gravitation》1998,30(5):695-700
Brinkmann has shown that conformally related Einstein spaces are either Ricci flat pp-waves or conformally flat spaces with one as de Sitter space and the other being flat. We herewith show that if gikand
are distinct metrics for which
, then both represent (generalised) pp-waves; and w,iis a homothetic conformal Killing vector of gik. It is further observed that in the situation
we can have many (and also non-conformally flat) conformally related solutions, unlike in Einstein spaces. In particular for perfect fluid coupling, we show that the conformally related solutions have to be Friedman-Robertson-Walker metrics with equation of state as
, or pp-waves depending on whether w,iis timelike, spacelike or null. 相似文献
57.
We establish a connection between conformally related Einstein spaces and conformai killing vectors (CKV). We begin with the conformal map and prove that (a) under the conformal mapping¯g
ik=–2gik, the necessary and sufficient condition for the tracefree part of the Ricci tensor (S
ik=Rik–(R/4)g
ik) to remain invariant is that
i is a CKV ofg
ik, and (b) the most general form for for conformally flat Einstein space, which is the de Sitter space, is composed of three terms each of which alone represents a flat space. The existence of gradient CKV (GCKV) is examined in relation to vacuum and perfect fluid spacetimes. 相似文献
58.
Crosslinking of sulphonated poly (ether ether ketone) using aromatic bis(hydroxymethyl) compound 总被引:1,自引:0,他引:1
Varsha R. Hande Swati Rao S.K. Rath Avinash Thakur M. Patri 《Journal of membrane science》2008,322(1):67-73
2,6-Bis(hydroxymethyl)-4-methyl phenol and 1,4-bis(hydroxymethyl) benzene have been used as crosslinkers in sulphonated poly (ether ether ketone) (SPEEK DS 65%, IEC 1.84 mequiv./g) for the preparation of proton exchange membranes (PEMs). Crosslinking of SPEEK has been achieved by thermally activated bridging of the polymer chain with the hydroxymethyl group of crosslinker through condensation reaction with sulphonic acid group. The physico-chemical properties of uncrosslinked and crosslinked membrane were evaluated in terms of ion exchange capacity (IEC), water uptake, ionic conductivity and mechanical properties. The crosslinked membrane showed controlled swelling, ionic conductivity of 25–50 mS/cm at 80 °C and good mechanical properties. The chemical stability of the crosslinked membranes was studied by Fenton's test. The % loss in weight and changes in physico-chemical properties of the treated membranes were determined. 相似文献
59.
Dhar S Reddy EM Shiras A Pokharkar V Prasad BL 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(33):10244-10250
"Gellan Gum", widely used in food and confectionary industry as a thickening and gelling agent, has been employed as a reducing and stabilizing agent for the synthesis of gold nanoparticles. These nanoparticles display greater stability to electrolyte addition and pH changes relative to the traditional citrate and borohydride reduced nanoparticles. Subsequently these have been used to load anthracycline ring antibiotic doxorubicin hydrochloride. The drug loaded on these nanoparticles showed enhanced cytotoxic effects on human glioma cell lines LN-18 and LN-229. 相似文献
60.
Analysis of a system of fractional differential equations 总被引:2,自引:0,他引:2
Varsha Daftardar-Gejji A. Babakhani 《Journal of Mathematical Analysis and Applications》2004,293(2):511-522
We prove existence and uniqueness theorems for the initial value problem for the system of fractional differential equations , where Dα denotes standard Riemann-Liouville fractional derivative, 0<α<1, and A is a square matrix. The unique solution to this initial value problem turns out to be , where Eα denotes the Mittag-Leffler function generalized for matrix arguments. Further we analyze the system , , 0<α<1, and investigate dependence of the solutions on the initial conditions. 相似文献