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排序方式: 共有491条查询结果,搜索用时 15 毫秒
81.
Anjleena Malhotra Tejinder Kaur Ranju Bansal 《Journal of heterocyclic chemistry》2019,56(10):2902-2911
In the present study, novel 4‐aryloxyquinazoline derivatives were synthesized and screened for in vitro cytotoxicity on human cancer cell lines at 10 μM. Some of the synthesized compounds displayed moderate to significant and selective cytotoxic activity against various leukemia, melanoma, ovarian, breast, and colon cancer cell lines. (E)‐3‐(3,4‐Dimethoxyphenyl)‐1‐(4‐(quinazolin‐4‐yloxy)phenyl)prop‐2‐en‐1‐one ( 9b ) was the most potent compound among all with an average growth inhibition of 70% against leukemia cancer cell lines. The compound also produced strong inhibition (75%) of colon cancer cell lines with 42.58% lethality of HCT‐116 cell line. 相似文献
82.
Improvement on Quantum Teleportation of Three and Four Qubit States Using Multi-Qubit Cluster States
Verma Vikram Singh Nidhi Singh Ravi S. 《International Journal of Theoretical Physics》2021,60(10):3973-3981
International Journal of Theoretical Physics - In 2016, Li et al. [Int. J. Theor. Phys. 55, 1820–1823 (2016)] proposed schemes for quantum teleportation of certain class of three and four... 相似文献
83.
Jitendra Pratap Singh Neema Agarwal Varsha Sahni Vaneet Kumar Rahul Malhotra Dinesh Pathak 《印度化学会志》2022,99(9):100581
This research intends to expand a mathematical model for studying the non-Newtonian surge of blood through a hepatic artery in the presence of steno occlusive disease post-liver transplantation. Power law liquid demonstrates the non- Newtonian character of blood. The hemodynamic conduit of the fluid is altered by the occurrence of arterial stenosis. In our study, the difficulty is resolved by applying diagnostic methods with the assistance of marginal circumstances and consequences. The outcomes are explained graphically for unusual cases for such stenosis. The study design is based on a tensorial form and converts its solution using numerical and analytical techniques. Our study outcome suitably demonstrates that the mathematical model used corroborates with the clinical scenario of the patient with hepatic disease. 相似文献
84.
Chemoselective Chromium(II)‐Catalyzed Cross‐Coupling Reactions of Dichlorinated Heteroaromatics with Functionalized Aryl Grignard Reagents
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Dr. Andreas K. Steib Dr. Olesya M. Kuzmina Sarah Fernandez Dr. Sushant Malhotra Prof. Paul Knochel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(5):1961-1965
Chromium(II) chloride catalyzes the chemoselective cross‐coupling reaction of dichloropyridines with a range of functionalized (hetero)aromatic Grignard reagents at room temperature. Functional groups, such as esters and acetals, are well tolerated in this transformation. Previously challenging substrates, quinolines and isoquinolines, participate in the selective Cr‐catalyzed cross‐coupling in cyclopentyl methyl ether (CPME) as the solvent. The effective purging of Cr salts is demonstrated by using various solid supports. 相似文献
85.
Ajeet Kaushik Pratima R. Solanki Anees A. Ansari Sharif Ahmad Bansi D. Malhotra 《Electrochemistry communications》2008,10(9):1364-1368
The rabbit immunoglobulin antibodies (IgGs) have been immobilized onto nanobiocomposite film of chitosan (CH)–iron oxide (Fe3O4) nanoparticles prepared onto indium–tin oxide (ITO) electrode for detection of ochratoxin-A (OTA). Excellent film forming ability and availability of –NH2 group in CH and affinity of surface charged Fe3O4 nanoparticles for oxygen support the immobilization of IgGs. Differential pulse voltammettry (DPV) studies indicate that Fe3O4 nanoparticles provide increased electroactive surface area for loading of IgGs and improved electron transport between IgGs and electrode. IgGs/CH–Fe3O4 nanobiocomposite/ITO immunoelectrode exhibits improved characteristics such as low detection limit (0.5 ng dL−1), fast response time (18 s) and high sensitivity (36 μA/ng dL−1 cm−2) with respect to IgGs/CH/ITO immunoelectrode. 相似文献
86.
o-Methyl-substituted Me-IBX is the first modified analog of IBX that oxidizes alcohols in common organic solvents at room temperature, due to a composite of two factors, that is, low solubility and hypervalent twisting-promoted rate enhancement. Furthermore, the reagent is efficient for selective oxidation of sulfides to sulfoxides, a transformation that otherwise occurs only sluggishly with standard IBX. The facile synthetic accessibility and its mild as well as non-hazardous nature render Me-IBX a stable equivalent of Dess-Martin periodinane reagent in organic oxidations. 相似文献
87.
Polyaniline based nucleic acid sensor 总被引:1,自引:0,他引:1
Prabhakar N Arora K Singh H Malhotra BD 《The journal of physical chemistry. B》2008,112(15):4808-4816
Twenty-bases long NH2-modified DNA and PNA probes specific to a pathogen (Mycobacterium tuberculosis) were covalently immobilized onto a polyaniline (PANI)/Au electrode to detect nucleic acid hybridization with complementary, one-base mismatch and noncomplementary targets within 30 s using Methylene Blue. The PNA-PANI/Au electrode exhibits improved specificity (1000 times) and detection limit (0.125 x 10(-18) M) as compared to that of the DNA-PANI/Au electrode (2.5 x 10(-18) M). These PNA-PANI/Au electrodes can be utilized for detection of hybridization with the complementary sequence in 5 min sonicated M. tuberculosis genomic DNA within 1 min of hybridization time. These DNA-PANI/Au and PNA-PANI/Au electrodes can be used 6-7 and 13-15 times, respectively. 相似文献
88.
Mayo DJ Inbaraj JJ Subbaraman N Grosser SM Chan CA Lorigan GA 《Journal of the American Chemical Society》2008,130(30):9656-9657
The alignment of membrane proteins provides pertinent structural and dynamic information. Structural topology data gleaned from such studies can be used to determine the functional mechanisms associated with a wide variety of integral membrane proteins. In this communication, we successfully demonstrate, for the first time, the determination of the structural topology and helical tilt of an antimicrobial peptide magainin 2 using aligned X-band spin-label EPR spectroscopic techniques. This novel comparison unlocks many possibilities utilizing EPR spectroscopy to probe antimicrobial peptide topologies with increased sensitivity and may also give further clues to elucidate their corresponding mechanisms. 相似文献
89.
Prabhakar N Arora K Arya SK Solanki PR Iwamoto M Singh H Malhotra BD 《The Analyst》2008,133(11):1587-1592
Cysteine modified NH(2)-end peptide nucleic acid (PNA) (24-mer) probe and 5'-thiol end labeled deoxyribonucleic acid (DNA) probes specific to Mycobacterium tuberculosis have been immobilized onto BK-7 gold coated glass plates for the detection of complementary, one-base mismatch, non-complementary targets and complementary target sequence in genomic DNA of Mycobacterium tuberculosis using a surface plasmon resonance (SPR) technique. The DNA/Au and PNA/Au bio-electrodes have been characterized using contact angle, atomic force microscopy (AFM), electrochemical impedance spectroscopy (EIS) and cyclic voltammetric (CV) techniques, respectively. It is revealed that there is a 252 millidegrees SPR angle change in the case of PNA immobilization and 205 millidegrees for DNA immobilization, indicating increased amount of immobilized PNA molecules. Hybridization studies reveal that there is no binding of the non-complementary target to DNA/Au and PNA/Au electrode. Compared to the DNA/Au bioelectrode, PNA/Au electrode has been found to be more efficient for detection of one-base mismatch sequence. The PNA/Au bioelectrode shows better detection limit (1.0 ng ml(-1)) over the DNA-Au bioelectrode (3.0 ng ml(-1)). The values of the association (k(a)) and dissociation rate constant (k(d)) for the complementary sequence in case of the PNA/Au bioelectrode have been estimated as 8.5 x 10(4) m(-1) s(-1) and 3.6 x 10(-3) s(-1), respectively. 相似文献
90.
Khan R Kaushik A Solanki PR Ansari AA Pandey MK Malhotra BD 《Analytica chimica acta》2008,616(2):207-213
Zinc oxide nanoparticles (NanoZnO) uniformly dispersed in chitosan (CHIT) have been used to fabricate a hybrid nanocomposite film onto indium-tin-oxide (ITO) glass plate. Cholesterol oxidase (ChOx) has been immobilized onto this NanoZnO-CHIT composite film using physiosorption technique. Both NanoZnO-CHIT/ITO electrode and ChOx/NanoZnO-CHIT/ITO bioelectrode have been characterized using Fourier transform-infrared (FTIR), X-ray diffraction (XRD), cyclic voltammetry (CV), scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS) techniques, respectively. The ChOx/NanoZnO-CHIT/ITO bioelectrode exhibits linearity from 5 to 300 mg dl−1 of cholesterol with detection limit as 5 mg dl−1, sensitivity as 1.41 × 10−4 A mg dl−1 and the value of Michaelis-Menten constant (Km) as 8.63 mg dl−1. This cholesterol biosensor can be used to estimate cholesterol in serum samples. 相似文献