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301.
Erika Chung Yong Ji Yanjie Sun Richard J Kascsak Regina B Kascsak Pankaj D Mehta Stephen M Strittmatter Thomas Wisniewski 《BMC neuroscience》2010,11(1):130
Background
Alzheimer's Disease (AD) is the most common of the conformational neurodegenerative disorders characterized by the conversion of a normal biological protein into a β-sheet-rich pathological isoform. In AD the normal soluble Aβ (sAβ) forms oligomers and fibrils which assemble into neuritic plaques. The most toxic form of Aβ is thought to be oligomeric. A recent study reveals the cellular prion protein, PrPC, to be a receptor for Aβ oligomers. Aβ oligomers suppress LTP signal in murine hippocampal slices but activity remains when pretreated with the PrP monoclonal anti-PrP antibody, 6D11. We hypothesized that targeting of PrPC to prevent Aβ oligomer-related cognitive deficits is a potentially novel therapeutic approach. APP/PS1 transgenic mice aged 8 months were intraperitoneally (i.p.) injected with 1 mg 6D11 for 5 days/week for 2 weeks. Two wild-type control groups were given either the same 6D11 injections or vehicle solution. Additional groups of APP/PS1 transgenic mice were given either i.p. injections of vehicle solution or the same dose of mouse IgG over the same period. The mice were then subjected to cognitive behavioral testing using a radial arm maze, over a period of 10 days. At the conclusion of behavioral testing, animals were sacrificed and brain tissue was analyzed biochemically or immunohistochemically for the levels of amyloid plaques, PrPC, synaptophysin, Aβ40/42 and Aβ oligomers. 相似文献302.
Pankaj K. Agarwal Boris Aronov Vladlen Koltun Micha Sharir 《Discrete and Computational Geometry》2005,34(2):231-250
Let B be a set of n unit balls
in ℝ3. We show that the combinatorial complexity of the
space of lines in ℝ3 that avoid all the balls of B is O(n3+ε), for any ε > 0. This result has connections to
problems in visibility, ray shooting, motion planning, and
geometric optimization. 相似文献
303.
Ten dialkyldithiophosphate derivatives of phenylbismuth(III) of the type, Ph(3–n)Bi[S(S)P(OR)2]n [where n = 1; R = Me( 1 ), Et( 2 ), Pri( 3 ), Prn( 4 ) and Bun( 5 ); n = 2; R = Me( 6 ), Et( 7 ), Pri( 8 ), Prn( 9 ) and Bun( 10 )] have been synthesized by the reactions of triphenylbismuth(III) with corresponding dialkyldithiophosphoric acids in 1:1 and 1:2 stoichiometric ratios, respectively, in stirred benzene solution. The newly synthesized brown colored compounds, 1–10 have been characterized by elemental analyses, molecular weight measurements, IR and NMR (1H, 13C and 31P) spectral studies. The ligand diethyldithiophosphoric acid, [(C2H5O)2P(S)SH], and its organobismuth(III) derivatives, compounds 2 and 7 were administered to adult male rats by oral gavage at the dose of 25 mg per kg body weight per day, for 60 days, and their effects were evaluated and compared for changes in testicular morphology, circulatory concentrations of testosterone, FSH and LH, sperm dynamics, fertility index and testicular cell population dynamics. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
304.
Pankaj K. Agarwal 《Discrete and Computational Geometry》2001,26(2):185-186
305.
We review the current status of high energy exclusive processes and color transparency. 相似文献
306.
All Solid State Chromium(III) Selective Potentiometric Sensor Based on 2‐(1‐(2‐((3‐(2‐Hydroxyphenyl)‐1H‐pyrozol‐1‐yl)methyl)benzyl)‐1H‐pyrazol‐3‐yl)phenol 下载免费PDF全文
Pankaj Kumar Sanjeev Kumar Sapna Jain Bhawna Y. Lamba Girdhar Joshi Shefali Arora 《Electroanalysis》2014,26(10):2161-2167
Highly selective all solid state electrochemical sensor based on a synthesized compound i.e. 2‐(1‐(2‐((3‐(2‐hydroxyphenyl)‐1H‐pyrozol‐1‐yl)methyl)benzyl)‐1H‐pyrazol‐3‐yl)phenol (I) as an ionophore has been prepared and investigated for the selective quantification of chromium(III) ions. The effect of various plasticizers, viz. dibutyl phosphonate (DBP), dibutyl(butyl) phosphonate (DBBP), nitrophenyl octyl ether (NPOE), tris‐(2‐ethylhexyl)phosphonate (TEP), tri‐butyl phosphonate (TBP), dioctyl phthalate (DOP), dioctyl sebacate (DOS), benzyl acetate (BA) and acetophenone (AP) along with anion excluders NaTPB (sodium tetraphenyl borate) and KClTPB (potassium(tetrakis‐4‐chlorophenyl)borate was also studied. The optimum composition of the best performing membrane contained (I):KClTPB:NPOE:PVC in the ratio 15 : 3 : 40 : 42 w/w. The sensor exhibited near Nernstian slope of 20.1±0.2 mV/decade of activity in the working concentration range of 1.2×10?7–1.0×10?1 M, and in a pH range of 3.8–4.5. The sensor exhibited a fast response time of 10 s and could be used for about 5 months without any considerable divergence in potentials. The proposed sensor showed very good selectivity over most of the common cations including Na+, Li+, K+, Cu2+, Sr2+, Ni2+, Co2+, Ba2+, Hg2+, Pb2+, Zn2+, Cs+, Mg2+, Cd2+, Al3+, Fe3+and La3+. The activity of Cr(III) ions was successfully determined in the industrial waste samples by using this sensor. 相似文献
307.
An efficient three-step methodology developed for the preparation of 1,2-amino alcohols. In the first step a rapid coupling between bromoketones and potassium phthalimide in ionic liquid produced α-phthalimido ketones in quantitative yields, which is followed by a facile reduction using NaCNBH3 in acetic acid to give corresponding phthalimido alcohols and finally effecting hydrazinolysis in water at 60 °C to yield biologically important 1,2-amino alcohols. 相似文献
308.
Pankaj K. Sharma A. K. Rai Yashpal Singh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):2147-2154
The reactions of triphenylantimony(v) isopropoxide with 2,2-disubstituted benzothiazolines in a 1:2 molar ratio in refluxing benzene solution yielded the corresponding triphenylantimony(v) derivatives (1–5) of the type Ph3Sb[SC6H4N: C(R)CH2C(O)R']2, [Where, R═CH3, R'═CH3(1); R═CH3, R'═C6H5(2); R═CH3, R'═4-CH3C6H4(3); R═CH3, R'═4-ClC6H4(4); and R═CF3, R'═C6H5(5)]. All of these newly synthesized derivatives have been characterized by elemental analyses and molecular weight measurements as well as IR and NMR [1H and 13C] spectral studies. On the basis of spectral data, seven-coordination around central antimony atom has been assigned to these derivatives. 相似文献
309.
Shivaji H. Shelke Pravin C. Mhaske Pankaj Hande Vivek D. Bobade 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):1262-1270
A novel series of 1-((4-methyl-2-substituted thiazol-5-yl)methyleneamino)-2-substituted isothiourea derivatives was synthesized by alkylation of (Z/E)-1-((4-methyl-2-substituted thiazol-5-yl)methylene)thiosemicarbazide with alkylhalide in acetone. All the newly synthesized compounds were characterized by spectral (IR, 1H NMR, 13C NMR, and mass spectrometry) methods. The newly synthesized compounds were screened for in vitro antimicrobial activity. Most of the compounds show moderate to excellent antimicrobial activity. [Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfer, and Silicon and the Related Elements for the following free supplemental files: Additional figures and tables.] 相似文献
310.
Najam Akhtar Shakil Mukesh Kumar Singh Alka Pandey Jitendra Kumar Pankaj Virinder S. Parmar 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(3):241-247
The formation of micelles in a solvent that is selective for one of the blocks is one of the most important and useful properties of block copolymers. We had synthesized copolymers of polyethylene glycol and various dimethyl esters, which self assemble into nano micellar aggregates in aqueous media. In the present work, we have utilized these nano micelles for the encapsulation of carbofuran, [2,3–dihydro-2,2-dimethylbenzofuran-7-yl methylcarbamate], a systemic insecticide-nematicide, for the development of controlled release formulation. 相似文献