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排序方式: 共有142条查询结果,搜索用时 15 毫秒
1.
脑卒中的早期中西医结合康复治疗   总被引:8,自引:0,他引:8  
通过观察脑卒中患者的神经功能缺损积分,日常生活活动能力、生存质量,以探讨早期中西医结合康复治疗脑卒中的临床疗效。  相似文献   
2.
3He/4He ratios in samples of sea water obtained at depths from surface to 300 m in the upper layer of the Western Pacific Ocean were measured by a mass spectrometer VG5400. The lateral and vertical distribution of He isotopes in the studied area was discussed in detail on the basis of 3He/4He ratios. Excess and depleted 3He. in relation to δ3He value of surface water in equilibrium with air has been discussed in the area, which may be mainly attributed to the incorporation of the North Pacific Intermediate Water with the Equatorial Upwelling and the exchange of water masses between the South China Sea and the Western Pacific, respectively. The present work in Western Pacific has also indicated that He isotopes may be used as a tracer for mixing processes of water masses and oceanic circulation.  相似文献   
3.
The concentration, source of manganese and iron in ferromanganese nodules and therelation between nodules and sedimentary environments are discussed in detail by asynthetical study on chemical information of ferromanganese nodules and correspondingsediment, pore water and geological, biological (bacteria) information in 26 stations fromthe North Pacific region (7- 13°N, 178- 165°W). The result shows that (i) the concen-tration and distribution characteristics of magnese and iron in ferromanganese nod-ules differ in different types of nodules, however, the concentration decreases with theincrease in grain sizes of nodules; (ii) the source of iron in different types of nodulesis basically the same, i. e. the slow sedimentation of overlying water; (iii) manganesein nodules comes mainly from the diffusion of Mn~(2+) in the pore water, and Mn~(2+) fromthe reduction of Mn~(4+) in sediments by the medium of bacteria. As the distribution of bac-teria is believed to be strongly affected by the sedimentary envi  相似文献   
4.
A comprehensive review of the development of assays, bioprobes, and biosensors using quantum dots (QDs) as integrated components is presented. In contrast to a QD that is selectively introduced as a label, an integrated QD is one that is present in a system throughout a bioanalysis, and simultaneously has a role in transduction and as a scaffold for biorecognition. Through a diverse array of coatings and bioconjugation strategies, it is possible to use QDs as a scaffold for biorecognition events. The modulation of QD luminescence provides the opportunity for the transduction of these events via fluorescence resonance energy transfer (FRET), bioluminescence resonance energy transfer (BRET), charge transfer quenching, and electrochemiluminescence (ECL). An overview of the basic concepts and principles underlying the use of QDs with each of these transduction methods is provided, along with many examples of their application in biological sensing. The latter include: the detection of small molecules using enzyme-linked methods, or using aptamers as affinity probes; the detection of proteins via immunoassays or aptamers; nucleic acid hybridization assays; and assays for protease or nuclease activity. Strategies for multiplexed detection are highlighted among these examples. Although the majority of developments to date have been in vitro, QD-based methods for ex vivo biological sensing are emerging. Some special attention is given to the development of solid-phase assays, which offer certain advantages over their solution-phase counterparts.  相似文献   
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Western blot (protein immunoblot) is a widely used analytical technique in molecular biology. Utilizing the specific recognizing primary antibody, proteins immobilized on various matrix are investigated by subsequent visualization steps, for example, by the horse radish peroxidase conjugated secondary antibody incubation. Methods to improve the sensitivity in protein identification or quantification are appreciated by biochemists. Herein, we report a new strategy to amplify Western blot signals by constructing a probe with proximal labeling and IgG targeting abilities. The R118G mutation attenuated the biotin-AMP binding affinity of the bacterial biotin ligase BirA*, offering a proximity-dependent labeling ability, which could be used as a signal amplifier. We built a BirA*-protein A fusion protein (BioEnhancer) that specifically binds to IgG and adds biotin tags to its proximal amine groups, enhancing the immunosignal of target proteins. In our experiments, the BioEnhancer system amplified the immunosignal by tenfold compared to the standard western blot. Additionally, our strategy could couple with other signal enhancement methods to further increase the western blot sensitivity.  相似文献   
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The development of capillary electrophoresis, especially CE-SDS devices, has led CE-SDS to become an established tool in a wide range of applications in the analysis of biopharmaceuticals and is increasingly replacing its method of origin, SDS-PAGE. The goal of this study was to evaluate the comparability of molecular weight (MW) determination especially by CE-SDS and SDS-PAGE. For ensuring comparability, model proteins that have little or no posttranslational modifications and an IgG antibody were used. Only a minor influence of sample preparation conditions, including sample buffer, temperature conditions, and different reducing agents on the MW determination were found. In contrast, the selection of the MW marker plays a decisive role in determining the accurate apparent MW of a protein. When using different MW markers, the deviation in MW determination can exceed 10%. Interestingly, CE-SDS and 10% SDS-PAGE hardly differ in their trueness of MW determination. The trueness in relation to the reference MW for each protein was calculated. Although the trueness values for the model proteins considered range between 1.00 and 1.11 using CE-SDS, they range between 0.93 and 1.03 on SDS-PAGE, depending on the experimental conditions chosen.  相似文献   
8.
A new radiolarian genus, Eoalbaillella belonging to Albaillellidae Deflandre emend. Holdsworth, is proposed from the Early Devonian in Western Yunnan, Southwestern China. Its test is composed of an imperforate lamellar shell and an elongate triangular framework, of which the upper part is enclosed by the lamellar shell and the lower part, without the shell, has the shape of the letter X. The relations between new genus and other radiolarian genera are studied and the type species of the genus is described.  相似文献   
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In this paper, we describe an Aptian (Early Cretaceous) larger foraminiferal species Orbitolina (Mesorbitolina) parva from the limestone olistoliths in the lower part of the Yezo Group in the Yubari–Ashibetsu area, central Hokkaido and from limestone pebbles in the lowermost part of the Yezo Group in the Nakagawa area, northern Hokkaido. This is the first report of this species from the circum-North Pacific regions. Based on its occurrences, the shallow-marine carbonates, re-deposited in the lower part of the Yezo Group, are precisely assigned in age to the Late Aptian. Comparison of the lower part of the Yezo Group in central and northern Hokkaido indicates differences of the Aptian–Albian depositional history between the two areas. This study reveals that after Late Aptian, Mesogean key taxa (typical Cretaceous Tethyan biota) demised in the Northwest Pacific.  相似文献   
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