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921.
镧在细胞膜上键合形态研究   总被引:6,自引:2,他引:4  
研究了一种简单快速的富膜细胞组分的提取和分离方法,并运用这种方法研究了大豆幼苗根细胞膜上La结合形态,La末与膜蛋白结合,而是与一非膜蛋白组分呈优势结合。  相似文献   
922.
时间表问题与遗传算法   总被引:1,自引:0,他引:1  
通过对时间表问题和遗传算法的认识,探讨用遗传算法求解时间表问题,并给出一个实例。  相似文献   
923.
Organic electroluminescent devices (OELDs) have attracted much attention for several years because of their potential application in large area, multi-colored flat panel displays1-5. The green organic EL display using Alq3 as emitter was commercialized in 19976. However, red-emitting OELD with excellent properties has not been well developed. In order to realize practical full-color OELDs, it is considered very important to develop red and blue emitting materials with excellent propert…  相似文献   
924.
The determination of molecular weights (Mw) of polysaccharides has served as an important process since the physical properties of the polysaccharides are closely related to their Mw and/or molecular weights distribution (MWD). For Mw and MWD determinations, high performance gel permeation chromatography (HPGPC) has gained wide acceptance as a preferred method due to its high sensitivity, speed and reproducibility. In chromatography, it is well known that the molecular weights are determ…  相似文献   
925.
The extraordinarily rapid growth of malignant tumors depends heavily on the glucose metabolism by the pathways of glycolysis and mitochondrial oxidative phosphorylation to generate adenosine 5′-triphosphate (ATP) for maintaining cell proliferation and tumor growth. This study reports a tumor chemical suffocation therapeutic strategy by concurrently suppressing both glycolysis and mitochondrial oxidative phosphorylation (OXPHOS) via the co-deliveries of EDTA and rotenone into a glutathione (GSH)-overexpressed tumor microenvironment. EDTA is to block the glycolytic pathway through inhibiting the activity of glycolytic enzymes via the chelation of magnesium ion, a co-worker of glycolytic enzymes, despite the presence of Ca2+. Meanwhile rotenone is to inhibit the mitochondrial OXPHOS. This work provides a novel tumor suffocation strategy by the co-deliveries of glucose metabolism inhibitors, especially by de-functioning glycolytic enzymes via eliminating their co-worker magnesium.

The EDTA- and Rotenone-loaded MPER nanoparticles have been synthesized to suffocate tumor cells to death through inhibiting glycolytic process and mitochondrial oxidative phosphorylation simultaneously in vitro and in vivo.  相似文献   
926.
The interaction between 3-(4′-methylphenyl)-5-(4′-methyl-2′-sulfophenylazo) rhodanine (M4MRASP) and bovine serum albumin (BSA) was studied by using spectrofluorimetry. It was shown in fluorescence spectrums that the quenching mechanism of BSA by M4MRASP was a static quenching. Meanwhile, the binding constant and binding site numbers were calculated. The action distance (r = 8.03 nm) and energy transfer efficiency (E = 0.12) between donor (BSA) and acceptor (M4MRASP) were obtained according to the theory of Förster non-radiation energy transfer. The effect of M4MRASP on the conformation of BSA was further analyzed by using synchronous fluorescence spectrometry. A new model of the interaction between small organic molecule and biomacromolecule was established. The results offered a reference for the studies on the biological effects and action mechanism of small molecule with protein.  相似文献   
927.
Significant progress has been made in understanding the nature of the transition state andthe paths for electron transfer, especially the influences of environmental factors and themolecular properties on the electron transfer rate. These classical and semi-classical, aswell as quantum-mechanical theory, have been very successful in rationalizing severalstructure-reactivity relationships and in predicting novel features of reactivity. Thesemodels established some links between the electron tra…  相似文献   
928.
929.
During the past decade, dense-type oxygen-permeable ceramic membranes have received considerable attention both in the fields of scientific research and industrial application1, 2. Such membranes have mixed oxygen-ionic and electronic conductivity, and they can permeate oxygen at high temperature under an oxygen gradient without the need of outside connecting line and electrodes. Envisioned applications range from small scale oxygen pumps for medical use to large scale integrated gasification …  相似文献   
930.
IntroductionOrganomercurials have been used extensively in organic synthesis and synthesis of other organometallics due to their ability to accommodate practically all the important organic functional groups and their ease in undergoing transmetallation for syntheses of transition metal organometallics which are very useful in organic synthesis. Recently, we reported the synthesis of optically active 1,2-disubstituted cyclomercurated ferrocenylimines by transmetallation reaction of planar chir…  相似文献   
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