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1.
ABO hemolytic disease of the newborn (ABO-HDN), which may cause neonatal jaundice and polycythemia, or even stillbirth or neonatal death, is widespread in China. Prenatal testing for the fetal ABO blood group can reduce unnecessary concerns or ensure prompt treatment. Herein, we presented a method to employ high-density silica microbeads (SiO2 MBs) for capturing fetal nucleated red blood cells (fnRBCs) in maternal peripheral blood, and we detected the ABO genotype of the fetus using these captured cells. We evaluated 52 patients using the SiO2 MBs. Among 26 pregnant women with type O blood, 8 (30.8%) of the fetuses had type A blood, 5 (19.2%) had type B blood, and 13 (50%) had type O blood. SRY genes were detected in all 27 male fetuses. This study represents a simple and effective method for noninvasive prenatal detection of the fetal ABO genotype. We believe that this method has great potential for noninvasive prenatal testing of the fetal Rh blood group and other fetal diseases as well.  相似文献   
2.
A single microbead‐based fluorescence imaging (SBFI) strategy that enables detection of protein kinase activity from single cell lysates is reported. We systematically investigated the ability of various rare earth (RE) ions, immobilized on the microbead, for specific capturing of kinase‐induced phosphopeptides, and Dy3+ was found to be the most prominent one. Through the efficient concentration of kinase‐induced fluorescent phosphopeptides on a Dy3+‐functionalized single microbead, kinase activity can be detected and quantified by reading the fluorescence on the microbead with a confocal fluorescence microscope. Owing to the extremely specific recognition of Dy3+ towards phosphopeptides and the highly‐concentrated fluorescence accumulation on only one microbead, ultrahigh sensitivity has been achieved for the SBFI strategy which allows direct kinase analysis at the single‐cell level.  相似文献   
3.
Mesocarbon microbeads (MCMB) were prepared by pyrolysis of coal-tar pitch in the presence of rosin, and characteristics of the pitch-rosin mixtures and the MCMB were studied. Pyrolysis behavior of the pitch-rosin mixtures was investigated by thermogravimetric analysis (TGA), and chemical structures of the pyrolysated pitch-rosin mixtures were studied using Fourier transform infrared spectroscopy (FTIR) technique. Optical textures of the pyrolysated pitch-rosin mixtures were characterized by polarized-light microscopy. In addition, morphologies and microstructures of the MCMB, extracted from the pyrolysated pitch-rosin mixtures, were studied using scanning electron microscopy (SEM) and transmission electron microscopy (TEM), respectively. Results show that the rosin addition contributes to a notable increase of MCMB yield as well as a decrease in the aromaticity index of the pyrolysated pitch-rosin mixtures. Moreover, the pyrolysis conditions have great effect on the morphologies and yields of MCMB. When the pitch-rosin mixtures are pyrolysated at 450 °C for 1.5-2.5 h, the MCMB yields arrive at 33.8-54.6 wt.% of the pyrolysated pitch-rosin mixtures.  相似文献   
4.
Nano-composite of Fe-doped anatase TiO2 nanocrystals loaded on the hollow glass microbeads was prepared by co-thermal hydrolysis deposition and calcining treatment. The adherence of TiO2 mesoporous layers to the surfaces of hollow glass microbeads prevented the aggregation of TiO2 nanoparticles and benefited to their catalytic activity. The doping of Fe ions makes the absorption edge of the TiO2 based nano-composite red-shifted into the visible region. An effective photodegradation of the methyl orange aqueous solution was achieved under visible light (λ>420 nm) irradiation, revealing the potential applicability of such nano-composite in some industry fields, such as air and water purifications.  相似文献   
5.
The mesoporous carbon material with large pore volume and high surface area by a simple situ MgO template method is synthesized, which is utilized as cathode to assemble a high performance lithium ion capacitor.  相似文献   
6.
The ability to construct self‐healing scaffolds that are injectable and capable of forming a designed morphology offers the possibility to engineer sustainable materials. Herein, we introduce supramolecular nested microbeads that can be used as building blocks to construct macroscopic self‐healing scaffolds. The core–shell microbeads remain in an “inert” state owing to the isolation of a pair of complementary polymers in a form that can be stored as an aqueous suspension. An annealing process after injection effectively induces the re‐construction of the microbead units, leading to supramolecular gelation in a preconfigured shape. The resulting macroscopic scaffold is dynamically stable, displaying self‐recovery in a self‐healing electronic conductor. This strategy of using the supramolecular assembled nested microbeads as building blocks represents an alternative to injectable hydrogel systems, and shows promise in the field of structural biomaterials and flexible electronics.  相似文献   
7.
在内部分散超顺磁性Fe3O4纳米粒子的二乙烯苯交联聚丙烯酸微球表面引入原子转移自由基聚合(ATRP)引发剂,引发聚合向微球表面分别引入P(GMMA-r-DMAEMA-r-GMA)、P(GMMA-r-DMAEMA)和P(GMMA-r-GMA)无规共聚物刷(GMMA为甲基丙烯酸甘油单酯,DMAEMA为甲基丙烯酸-N,N-二甲氨基乙酯,GMA为甲基丙烯酸缩水甘油酯),聚合物刷中GMMA链节的作用是使聚合物刷具有亲水性,DMAEMA引入氨基,GMA引入环氧基.研究了青霉素G酰化酶在这些载体上的固定化和其酶活性.结果表明,同时引入环氧基和氨基的P(GMMA-r-DMAEMA-r-GMA)刷磁性微球固定化青霉素G酰化酶的活性和活性收率都最高,其固定化动力学比只含环氧基P(GMMA-r-GMA)刷磁性微球的好.固定化酶比自由酶更耐热,固定化酶的最佳pH值比自由酶的略高,固定化酶重复使用10次后其活性保留70%.  相似文献   
8.
Monodisperse sized crosslinked polystyrene (PS) beads prepared by reaction of styrene (S) and divinylbenzene (DVB), in batch emulsion copolymerization in the absence of emulsifiers, are not uniformly crosslinked, because DVB is more reactive than S. For copolymerization of 1 to 10 mol % DVB and S, within each crosslinked PS microbead, the crosslink density varies by a factor exceeding two and decreases with increased conversion. A semicontinuous copolymerization, involving incremental additions of DVB, produces uniformly crosslinked PS beads. For both copolymerization techniques, Tg correlates well with crosslink density and PS beads are spherical and monodisperse in size. © 1992 John Wiley & Sons, Inc.  相似文献   
9.
煤焦油热解制备中间相炭微球   总被引:8,自引:1,他引:7  
含有3.7%吡啶不溶物的煤焦油和经热过滤去除吡啶不溶物的净化焦油在自升压下聚合,产物经热过去除母兴,滤饼用吡啶抽提至无色得中间相炭微球,在偏光显微镜下观察聚合产物的结构,在扫描电镜下观察中间相炭微球的形貌。结果表明,由于聚合产物的粘度较低,所产生的MCMB易于从母液中分离出来;原料中的吡啶不溶物有利于阻止MCMB的融并,在一定程度上可起到控制球径的作用;对无吡啶不溶物煤焦油高温短时间聚合后骤冷有利  相似文献   
10.
A facile approach to the synthesis of pressure and temperature dual‐responsive polystyrene (PS) microbeads with controlled sizes via dispersion polymerization is described. Three different luminophors are selected and directly introduced into the reaction system and thus incorporated into the resultant PS microbeads during polymerization. By manipulating the reaction conditions, including concentrations of the initiator and monomer, polarity of the reaction medium, and injection rate for the monomer, uniform PS microbeads with sizes ranging from 1 to 5 μm are obtained. When a light source centered at 365 nm is used to excite all the luminophors in the PS beads, three distinct and resolvable emission peaks corresponding well with the luminophors are observed. By taking advantage of their sensitive responses to both pressure and temperature, the PS beads can be utilized for quantitative measurements of these two stimulations simultaneously. The PS beads loaded with multiple luminophors have the ability to serve as building blocks for the fabrication of novel sensing and imaging devices and therefore provide a promising strategy for the study of aerodynamics.  相似文献   
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