4,202 research outputs found
Progress of Enantioselective Nitrile Biotransformations in Organic Synthesis
Recent progress of enantioselective biotransformations of nitriles including various functionalized nitriles, ?-hydroxy and ?-amino nitriles, oxirane- and aziridine-containing carbonitriles is summarized in this short review article
Anion Recognition by Charge Neutral Electron-deficient Arene Receptors
Anion-? interactions are newly emerging non-covalent interactions and have attracted considerable attention from both theoreticians and supramolecular chemists. This short review article summarizes the recent advances in anion recognition using charge neutral electron-deficient aromatic
compounds
2-(4-Bromophenyl)-2-methyl-2,3-dihydroquinazolin-4(1H)-one
In the title compound, C15H13BrN2O, the pyrimidine ring adopts a skew boat conformation. The amino H atom forms an intermolecular hydrogen bond with the carbonyl O atom of an adjacent molecule, forming an inversion dimer. Another lone pair of electrons on the same carbonyl O atom acts as acceptor for another N—H⋯O intermolecular hydrogen bond with a neighbouring molecule, forming chains along the c axis
The Navigation Engineering in Developed Hydropower Station
Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchive
Preparation and evaluation of peptide-dendrimer-paclitaxel conjugates for treatment of heterogeneous stage 1 nonsmall cell lung cancer in 293T and L132 cell lines
Purpose: To develop peptide-dendrimer-paclitaxel conjugates for the treatment of heterogeneous stage 1 non small cell lung cancer (NSCLC) in 293T and L132cell line.Method: Dendrimer-paclitaxel conjugates (PAMAM-PTX) were prepared by NHS method and the conjugates were used for the synthesis of peptide-dendrimer-paclitaxel conjugates (GE-PAMAM-PTX). The particle sizes of PAMAM-PTX and GE-PAMAM-PTX were measured. Entrapment efficiency of PTX in PAMAM-PTX was measured while GE-PAMAM-PTX. PTX release from PAMAM-PTX and GEPAMAM- PTX was determined using a dialysis bag in pH 7.4 phosphate buffer. The cytotoxicity of PAMAM-PTX, GE-PAMAM-PTX, PAMAM and PTX was evaluated by 3-(4,5-dimethylthiazol-2-Yl)-2,5- diphenyltetrazolium bromide (MTT) assay using 293T cell lines. In vitro cellular uptake assay of PAMAM-PTX and GE-PAMAM-PTX and PTX at concentrations ranging from 0.01 to 0.5μM for 8 h was carried out in NSCLC cell lines 293T and L132.Results: More than 95 % entrapment efficiency of GE-PAMAM-PTX was observed with loading efficiency of 25 %. GE-PAMAM-PTX conjugates showed sustained release of PTX (~85 %) towards the end of 50 h. GE-PAMAM-PTX conjugates were more cytotoxic than pure PTX and PAMAM-PTX conjugates. The remarkable uptake of GE-PAMAM-PTX appear to be due to receptor-mediated endocytosis in the cell lines. The presence of ligand (GE) on PAMAM-PTX surface enabled the complex to bind to the over-expressed receptors on the cell lines.Conclusion: GE-PAMAM-PTX can facilitate targeting of paclitaxel to lung cancer cell lines and tumors and facilitate release of the drugs in a sustained manner to improve the therapeutic efficacy of PTX.Keywords: Paclitaxel, Lung cancer, Non-small cell lung cancer, Dendrimer, Peptide, PAMA
Mobile phone dependence, social support and impulsivity in Chinese university students
This study examined the frequency of mobile phone dependence in Chinese university students and explored its association with social support and impulsivity. Altogether, 909 university students were consecutively recruited from a large university in China. Mobile phone use, mobile phone dependence, impulsivity, and social support were measured with standardized instruments. The frequency of possible mobile phone use and mobile phone dependence was 78.3% and 7.4%, respectively. Multinomial logistic regression analyses revealed that compared with no mobile phone dependence, possible mobile phone dependence was significantly associated with being male (p = 0.04, OR = 0.7, 95% CI: 0.4–0.98), excessive mobile phone use (p \u3c 0.001, OR = 1.2, 95% CI: 1.09–1.2), and impulsivity (p \u3c 0.001, OR = 1.05, 95% CI: 1.03–1.06), while mobile phone dependence was associated with length of weekly phone use (p = 0.01, OR = 2.5, 95% CI: 1.2–5.0), excessive mobile phone use (p \u3c 0.001, OR = 1.3, 95% CI: 1.2–1.4), and impulsivity (p \u3c 0.001, OR = 1.08, 95% CI: 1.05–1.1). The frequency of possible mobile phone dependence and mobile phone dependence was high in this sample of Chinese university students. A significant positive association with impulsivity was found, but not with social support
Advances in research on personalized venous thromboembolism risk assessment tools
AbstractThis paper describes the definition of venous thromboembolism and introduces to personalized venous thromboembolism risk assessment tools overseas. Thoughts are given on the development, amendment, application and validation of these tools. The paper provides a reference for building personalized venous thromboembolism risk assessment tools in China
Novel Wideband Metallic Patch Antennas with Low Profile
Two planar metallic patch (MP) antennas with low profiles are investigated and compared in this paper. The MP of each antenna consists of metallic patch cells and it is centrally fed by a rectangular slot. Two modes with close resonance frequencies are excited, providing a quite wide bandwidth. The antenna principle is explained clearly through a parametric study. Simulated and measured results show that the MP antennas with profile of 0.06λ0 can obtain a 10 dB impedance bandwidth of ~32% and an average gain of ~10 dBi
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