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991.
Yue-fei Wang Jie Wang Jing Wu Ping Xu Yi-qi Wang Jun-jie Gao Danielle Hochstetter 《Journal of Zhejiang University. Science. B》2014,15(2):173-180
The conditions for extracting polysaccharides from tea (Camellia sinensis L.) fruit peel (TFPPs) were studied. Three parameters (temperature, time, and liquid/solid ratio) affecting the extraction of TFPP were optimized using response surface methodology (RSM). Under the optimized conditions, the yield of TFPP was predicted to be 4.98%. The physicochemical properties, in vitro antioxidant activities, and inhibitory effects on α-glucosidase of fractionated TFPPs (TFPP-0, TFPP-20, TFPP-40, and TFPP-60) were investigated. We found that the TFPPs were all acid protein-bound heteropolysaccharides, although with different chemical compositions. They had not only remarkable scavenging activity on 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) and reducing activity, but also excellent inhibitory potential against α-glucosidase in vitro. Our results suggest that tea fruit peel could be treated as a potential bioresource for the development of polysaccharide antioxidants. 相似文献
992.
Tossapon Wongtangprasert Wirongrong Natakuathung Umaporn Pimpitak Anumart Buakeaw Tanapat Palaga Kittinan Komolpis Nanthika Khongchareonporn 《Journal of Zhejiang University. Science. B》2014,15(2):165-172
A novel monoclonal antibody (MAb) against oxytetracycline (OTC) was generated and characterized. The MAb was used in the development of an enzyme-linked immunosorbant assay (ELISA)-based detection system. An OTC-bovine serum albumin (BSA) conjugate was prepared and used in the immunization of mice. A conventional somatic cell fusion technique was used to generate MAb-secreting hybridomas denoted 2–4F, 7–3G, and 11–11A. An indirect competitive ELISA (icELISA) was applied to measure the sensitivity and specificity of each MAb in terms of its 50% inhibitory concentration (IC50) and percentage of cross-reactivity, respectively. MAb 2–4F exhibited the highest sensitivity, with an IC50 of 7.01 ng/ml. This MAb showed strong cross-reactivity to rolitetracycline, but no cross-reactivity to other unrelated antibiotics. When MAb 2–4F was used to detect OTC from shrimp samples, the recoveries were in the range of 82%–118% for an intra-assay and 96%–113% for an inter-assay. The coefficients of variation of the assays were 3.9%–13.9% and 5.5%–14.9%, respectively. 相似文献
993.
Ying-ying LU Xian YANG Wen-qing CHEN Zhen-yu JU Zhang-fei SHOU Juan JIN Xiao-hui ZHANG Jiang-hua CHEN Hong JIANG 《Journal of Zhejiang University. Science. B》2014,15(6):566-574
Aging is one of the contributing risk factors for kidney diseases. Accumulating evidence prompts the view that telomere length in kidney tissue cells is an indicator for organismal aging. Previously identified aging markers (cathelin-related antimicrobial peptide (CRAMP), stathmin, elongation factor-1α (EF-1α), and chitinase) were associated not only with telomere driven aging in mice but also with human aging and chronic diseases. This study focuses on the relationship between these biomarkers and IgA nephropathy (IgAN) progression in the Chinese population. For 260 individuals, the four markers are determined in blind datasets using direct enzyme-linked immunosorbent assay (ELISA) and immunofluorescence staining. The expression levels of CRAMP and chitinase increased in blood plasma, urine, and kidney tissues during human IgAN progression. And for the other nephropathy, such as systemic lupus erythematosus (SLE), diabetic nephropathy (DN), and focal segmental glomerulosclerosis (FSGS), there is no protein upregulation with telomere shortening. Moreover, a combination of CRAMP and chitinase can distinguish patients with IgAN from healthy individuals with 88.2%/92.5% (plasma) and 74.3%/84.2% (urine) sensitivity/specificity. These data provide the experimental evidence that telomere shortening and related inflammatory proteins are associated with human IgAN, and it could be a new direction for the disease progression study. 相似文献
994.
Many household consumables contain volatile organic compounds(VOCs)as the active ingredient.Long term exposure to VOCs could cause various health problems,especially to the respiratory system.Graphene has attracted a lot of attention recently for its potential to be used as sensing material for VOCs.In this project we have constructed graphene/PVA composite based gas sensors for VOC detection.It was perceived that the polymer could introduce better selectivity to the sensor.Results suggest that the proposed sensor is highly sensitive to low molecular weight VOCs and that the manner in which the sensor respond to the vapour depends on the polarity or hydrophobicity of the vapour. 相似文献
995.
Combining fiber dissection,plastination, and tractography for neuroanatomical education: Revealing the cerebellar nuclei and their white matter connections
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Hisse Arnts Michiel Kleinnijenhuis Jan G.M. Kooloos Annelieke N. Schepens‐Franke Anne‐Marie van Cappellen van Walsum 《Anatomical sciences education》2014,7(1):47-55
In recent years, there has been a growing interest in white matter anatomy of the human brain. With advances in brain imaging techniques, the significance of white matter integrity for brain function has been demonstrated in various neurological and psychiatric disorders. As the demand for interpretation of clinical and imaging data on white matter increases, the needs for white matter anatomy education are changing. Because cross‐sectional images and formalin‐fixed brain specimens are often insufficient in visualizing the complexity of three‐dimensional (3D) white matter anatomy, obtaining a comprehensible conception of fiber tract morphology can be difficult. Fiber dissection is a technique that allows isolation of whole fiber pathways, revealing 3D structural and functional relationships of white matter in the human brain. In this study, we describe the use of fiber dissection in combination with plastination to obtain durable and easy to use 3D white matter specimens that do not require special care or conditions. The specimens can be used as a tool in teaching white matter anatomy and structural connectivity. We included four human brains and show a series of white matter specimens of both cerebrum and cerebellum focusing on the cerebellar nuclei and associated white matter tracts, as these are especially difficult to visualize in two‐dimensional specimens and demonstrate preservation of detailed human anatomy. Finally, we describe how the integration of white matter specimens with radiological information of new brain imaging techniques such as diffusion tensor imaging tractography can be used in teaching modern neuroanatomy with emphasis on structural connectivity. Anat Sci Educ. 7: 47–55. © 2013 American Association of Anatomists. 相似文献
996.
997.
徐国明 《唐山师范学院学报》2014,(6):27-30
(食)字由“(亼)”和“ (皀)”两部分构成。当我们结合“(食)”→“(即)”→“(饗)”→“(既)”这一系相连贯的古人用食动作,或者“”→“(飤)”→“”这一过程分析时,就会明确食字所从的“(亼)”象盖形,本义为盖子。食字所从的“皀”字甲骨文作:,其象:食器中堆满饭(小米饭)的形状(上部的数点表示饭散发的热气或香气)。食字由这两部分构成,但又不是如《说文》及《注》所认为的:食是会意字,意思由“亼”与“皀”两字所会。实际上(食)为象形字,象:食器中堆满饭并盖上盖子之形;它与(皀)字的意思相同都指:食器中堆满饭,二者仅有的不同在于(食)有盖子(皀)没有盖子。这是食字的本义,由这个意思可引出仅指食器中的饭食之食物,食物是供人吃的,由此又可指食用之食,如甲文(食麦)。在吃食的过程中食器中堆积如小山般的饭食会逐渐缺少,这就有了缺损义,由此又可指日月食,如(月有食)。吃食在一个时间段进行,由此又可指时间,如(大食)(小食)。 相似文献
998.
999.
网络传输可以分为四种形态:“一对一”,“多对一”,“一对多”和“多对多”。“一对一”是问题分解的终极,而“多对多”则是效率所追求的终极。由四种形态之间转变展开讨论,为了提高效率,网络传输应该转向“多对多”。群对群是“多对多”的另一种传输方式,或者说,是强调分群的“多对多”传输。 相似文献
1000.