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91.
Rongchen Dai Mengfan Liu Wan Najbah Nik Nabil Zhichao Xi Hongxi Xu 《Molecules (Basel, Switzerland)》2021,26(4)
Mycomedicine is a unique class of natural medicine that has been widely used in Asian countries for thousands of years. Modern mycomedicine consists of fruiting bodies, spores, or other tissues of medicinal fungi, as well as bioactive components extracted from them, including polysaccharides and, triterpenoids, etc. Since the discovery of the famous fungal extract, penicillin, by Alexander Fleming in the late 19th century, researchers have realised the significant antibiotic and other medicinal values of fungal extracts. As medicinal fungi and fungal metabolites can induce apoptosis or autophagy, enhance the immune response, and reduce metastatic potential, several types of mushrooms, such as Ganoderma lucidum and Grifola frondosa, have been extensively investigated, and anti-cancer drugs have been developed from their extracts. Although some studies have highlighted the anti-cancer properties of a single, specific mushroom, only limited reviews have summarised diverse medicinal fungi as mycomedicine. In this review, we not only list the structures and functions of pharmaceutically active components isolated from mycomedicine, but also summarise the mechanisms underlying the potent bioactivities of several representative mushrooms in the Kingdom Fungi against various types of tumour. 相似文献
92.
A phase transition was observed at 63-69 GPa and room temperature in vanadium with synchrotron x-ray diffraction. The transition is characterized as a rhombohedral lattice distortion of the body-centered-cubic vanadium without a discontinuity in the pressure-volume data, thus representing a novel type of transition that has never been observed in elements. Instead of driven by the conventional s-d electronic transition mechanism, the phase transition could be associated with the softening of C44 trigonal elasticity tensor that originates from the combination of Fermi surface nesting, band Jahn-Teller distortion, and electronic topological transition. 相似文献
93.
J.-L. Peng H. Ahn R.-H. Shu H.-C. Chui J.W. Nicholson 《Applied physics. B, Lasers and optics》2007,86(1):49-53
A mode-locked Er:fiber laser-based optical frequency comb with high stability in the repetition frequency and carrier-envelope offset (CEO) frequency is realized. The CEO beat signal was detected right after the supercontinuum generation by a compact single-beam f–2f self-referencing interferometer, which does not require further delay compensation. The stabilized repetition frequency has an out-of-loop tracking stability of 1.3×10-13/ for an integration time τ less than 1000 s, which is limited by the stability of the frequency measurement system. The stabilized CEO frequency has a residual fluctuation of 0.52 mHz measured with a 1 s gate time. This is, to our knowledge, the highest tracking stability realized for fiber laser-based optical frequency comb. PACS 06.30.Ft; 42.60.Lh; 42.55.Wd 相似文献
94.
The liver, kidney and muscle samples from seven cetaceans were digested by microwave digestion, and trace elements amounts of V, Cd, Cu, Zn, As, Cr, Ni, Mn, Se, Hg and Pb were determined by inductively coupled plasma mass spectrometry (ICP-MS), and the health risk assessment for Zn, Cu, Cd, Hg, Se in the liver was conducted. The results of international lobster hepatopancreas standard (TORT-2) showed acceptable agreement with the certified values, and the relative standard deviation (RSD) of eleven kinds of trace elements were less than 3.54%, showing that the method is suitable for the determination of trace elements in cetaceans. The experimental results indicated that different tissues and organs of the dolphins had different trace elements, presenting the tissue specificity. There is a certain inter-species difference among different dolphins about the bioaccumulation ability of the trace elements. The distribution of trace elements in whales presented a certain regularity: the contents of most elements in liver, kidney were much higher than the contents of muscle tissues, Cu, Mn, Hg, Se, and Zn exhibit the higher concentrations in liver, while Cd was mainly accumulated in kidney. And according to the health risk assessment in liver, the exceeding standardrate of selenium and copper in seven kinds of whales was 100%, suggesting that these whales were suffering the contamination of trace elements. The experimental results is instructive to the study of trace elements in cetaceans, while this is the first report for the concentrations in organs of Striped dolphin, Bottlenose dolphin, Fraser's Dolphin and Risso's dolphin in China, it may provide us valuable data for the conservation of cetaceans. 相似文献
95.
采用溶剂热法制备出铜铟铝硒Cu(In,Al)Se2 (CIASe)粉末,然后滴涂铜铟铝硒CIASe浆料获得前驱体薄膜,最后通过硒化/硫化过程制备出铜铟铝硒CIASe和铜铟铝硒硫CIASeS薄膜.通过XRD、SEM、XRF及光吸收等表征,发现所制备的薄膜为单相的黄铜矿结构,具有(112)择优取向.同时,在使用硫元素替代硒之后,薄膜的XRD主峰向高的2θ角度漂移,多孔薄膜也变得更加致密.薄膜带隙值也增加到更为合适的范围,从1.21 eV增加到1.33 eV,这也说明了硫化过程有利于提高CIASeS薄膜的质量. 相似文献
96.
Aiping Xi Zhongxin Xu Fengli Liu Yanli Xu Lijun Yu Jie Liu 《Russian Journal of Physical Chemistry B, Focus on Physics》2015,9(6):946-951
The aim of this present work is to investigate the interaction between doxorubicin and bovine serum albumin (BSA) in simulated physiological conditions by spectroscopic methods to reveal potential toxic effects of the drug. The results reflected that doxorubicin made the fluorescence quenching of BSA through a static quenching procedure. The binding constants at 293, 298, and 303 K were obtained as 2.53 × 105, 8.13 × 104, and 3.59 × 104 M–1, respectively. There may be one binding site of doxorubicin on BSA. The thermodynamic parameters indicated that the interaction between doxorubicin and BSA was driven mainly by hydrogen bonding and electrostatic forces. Synchronous fluorescence spectra and circular dichroism (CD) results showed doxorubicin binding slightly changed the conformation of BSA with secondary structural content changes. Förster resonance energy transfer (FRET) study revealed high possibility of energy transfer with doxorubicin-Trp-212 distance of 3.48 nm. The results of the present study may provide valuable information for studying the distribution, toxicological and pharmacological mechanisms of doxorubicin in vivo. 相似文献
97.
98.
Bin Zhou Yedi Xing Prof. Shu Miao Prof. Mingrun Li Prof. Wen‐Hua Zhang Prof. Can Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(39):12426-12431
A facile colloidal approach to synthesize Ag8(Ge1?x,Snx)(S6?y,Sey) nanocrystals (NCs) in a highly controlled way across the entire compositional ranges (0≤x≤1, 0≤y≤6) has been developed. The NCs exhibit a uniform size distribution, highly crystalline structure, over 1 g scalable synthesis, and tunable band gaps in the range of 0.88–1.45 eV by varying their chemical compositions. The Ag8GeS6 NCs with a band gap of approximately 1.45 eV were employed as a model light harvester to assess their applicability in solar cells by a full solution‐processing device, yielding an efficiency of 0.28 % under AM1.5 illumination, demonstrating their application potential in solar energy utilization. 相似文献
99.
Simultaneous In Situ Quantification of Two Cellular Lipid Pools Using Orthogonal Fluorescent Sensors 下载免费PDF全文
Dr. Shu‐Lin Liu Dr. Ren Sheng Matthew J. O'Connor Yang Cui Dr. Youngdae Yoon Svetlana Kurilova Dr. Daesung Lee Dr. Wonhwa Cho 《Angewandte Chemie (International ed. in English)》2014,53(52):14387-14391
Lipids regulate a wide range of biological activities. Since their local concentrations are tightly controlled in a spatiotemporally specific manner, the simultaneous quantification of multiple lipids is essential for elucidation of the complex mechanisms of biological regulation. Here, we report a new method for the simultaneous in situ quantification of two lipid pools in mammalian cells using orthogonal fluorescent sensors. The sensors were prepared by incorporating two environmentally sensitive fluorophores with minimal spectral overlap separately into engineered lipid‐binding proteins. Dual ratiometric analysis of imaging data allowed accurate, spatiotemporally resolved quantification of two different lipids on the same leaflet of the plasma membrane or a single lipid on two opposite leaflets of the plasma membrane of live mammalian cells. This new imaging technology should serve as a powerful tool for systems‐level investigation of lipid‐mediated cell signaling and regulation. 相似文献
100.
Yufei Shu Dr. Xing Lin Dr. Haiyan Qin Zhuang Hu Prof. Yizheng Jin Prof. Xiaogang Peng 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(50):22496-22507
This article offers a materials-chemistry perspective for colloidal quantum dots (QDs) in the field of display, including QD-enhanced liquid-crystal-display (QD-LCD) and QD-based light-emitting-diodes (QLEDs) display. The rapid successes of QDs for display in the past five years are not accidental but have a deep root in both maturity of their synthetic chemistry and their unique chemical, optical, and optoelectronic properties. This article intends to discuss the natural match of QD emitters for display and chemical means to eventually bring about their full potential. 相似文献