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Wang  Jun  Liu  Fangchao  Li  Jianxin  Huang  Keyong  Yang  Xueli  Chen  Jichun  Liu  Xiaoqing  Cao  Jie  Chen  Shufeng  Shen  Chong  Yu  Ling  Lu  Fanghong  Wu  Xianping  Zhao  Liancheng  Li  Ying  Hu  Dongsheng  Huang  Jianfeng  Gu  Dongfeng  Lu  Xiangfeng 《中国科学:生命科学英文版》2022,65(1):119-128
Science China Life Sciences - Evidence about the response patterns of fruit and vegetable consumption with the risk of cardiovascular disease (CVD) and all-cause mortality was inconsistent. These...  相似文献   
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A natural lectin from the serum of the shrimp Litopenaeus vannamei was purified to homogeneity by a single-step affinity chromatography using fetuin-coupled agarose. The purified serum lectin (named LVL) showed a strong affinity for human A/B/O erythrocytes (RBC), mouse RBC, chicken RBC and its haemagglutinating (HA) activity was specifically dependent on Ca2+ and reversibly sensitive to EDTA. LVL inactive form had a molecular mass estimate of 172 kDa and was composed of two non-identical subunits (32 and 38 kDa) cross-linked by interchain disulphide bonds. Significant LVL activity was observed between pH 7 and 11. In HA-inhibition assays performed with several carbohydrates and glycoproteins, LVL showed a distinct and unique specificity for GalNAc/GluNAc/NeuAc which had an acetyl group, while glycoproteins fetuin and bovine submaxillary mucin (BSM) had sialic acid. Moreover, this agglutinin appeared to recognise the terminal N- and O-acetyl groups in the oligosaccharide chain of glycoconjugates. The HA activity of L. vannamei lectin was also susceptible to inhibition by lipopolysaccharides from diverse Gram-negative bacteria, which might indicate a significant in vivo role of this humoral agglutinin in the host immune response against bacterial infections.  相似文献   
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Target tracking with wireless sensor networks (WSNs) has been a hot research topic recently. Many works have been done to improve the algorithms for localization and prediction of a moving target with smart sensors. However, the results are frequently difficult to implement because of hardware limitations. In this paper, we propose a practical distributed sensor activation algorithm (DSA2) that enables reliable tracking with the simplest binary-detection sensors. In this algorithm, all sensors in the field are activated with a probability to detect targets or sleep to save energy, the schedule of which depends on their neighbor sensors’ behaviors. Extensive simulations are also shown to demonstrate the effectiveness of the proposed algorithm. Great improvement in terms of energy-quality tradeoff and excellent robustness of the algorithm are also emphasized in the simulations.  相似文献   
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Therminator DNA polymerase is an efficient DNA-dependent TNA polymerase capable of polymerizing TNA oligomers of at least 80 nt in length. In order for Therminator to be useful for the in vitro selection of functional TNA sequences, its TNA synthesis fidelity must be high enough to preserve successful sequences. We used sequencing to examine the fidelity of Therminator-catalyzed TNA synthesis at different temperatures, incubation times, tNTP ratios and primer/template combinations. TNA synthesis by Therminator exhibits high fidelity under optimal conditions; the observed fidelity is sufficient to allow in vitro selection with TNA libraries of at least 200 nt in length.  相似文献   
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Dissolution and regeneration of collagen fibers using ionic liquid   总被引:1,自引:0,他引:1  
Native skin collagen fibers were successfully dissolved in the ionic liquid, 1-butyl-3-methylimidazolium chloride ([BMIM]Cl), and regenerated in different precipitators. The observation by polarized optical microscopy showed that the crystal structure of collagen fibers had been destroyed by [BMIM]Cl during the heating. Temperature-dependent FTIR was applied to detect the structural change of collagen/[BMIM]Cl during dissolving. The structure of regenerated collagen was characterized by FTIR and XRD. It showed that the triple helical structure of collagen had been partly destroyed during the dissolution and regeneration. The film forming ability and the thermostability of the regenerated collagen was highly dependent on the precipitating treatment. The possible mechanisms of dissolving of collagen in [BMIM]Cl and the regeneration in the precipitators have been proposed. The collagen/cellulose composite with different forms (film, fiber, gel) can be successfully prepared by using [BMIM]Cl as medium.  相似文献   
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胃粘膜损伤中EB病毒感染与P53抑癌基因突变的研究   总被引:1,自引:0,他引:1  
为了探讨EB病毒(EBV)感染与胃癌发生的关系,应用PCR技术对166例胃粘膜损伤标本的EBVDNA进行检测.其中66例应用银染PCR-SSCP分析技术检测了p53exon5~8突变情况,10例应用直接法原位PCR技术检测了EBV在组织中的感染情况。结果166例标本中EBV感染率为30.1%;EBV在细胞中感染大体是弥散型,主要存在于细胞核。66例标本中p53基因突变率为54.5%。对比分析,EBV阳性标本中p53基因突变率为75%(21/28),EBV阴性标本中p53基因突变率为39.5%(15/38)。结果表明,EBV对胃粘膜组织细胞具有易感性,p53基因突变在胃粘膜病变中是一个常发事件,EBV感染与p53基因突变之间存在着高度相关性.对癌症的发生具有重要作用。  相似文献   
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Bone morphogenetic protein (BMP) signaling regulates many different biological processes, including cell growth, differentiation, and embryogenesis. BMPs bind to heterogeneous complexes of transmembrane serine/threonine (Ser/Thr) kinase receptors known as the BMP type I and II receptors (BMPRI and BMPRII). BMPRII phosphorylates and activates the BMPRI kinase, which in turn activates the Smad proteins. The cytoplasmic region of BMPRII contains a "tail" domain (BMPRII-TD) with no enzymatic activity or known regulatory function. The discovery of mutations associated with idiopathic pulmonary artery hypertension mapping to BMPRII-TD underscores its importance. Here, we report that Tribbles-like protein 3 (Trb3) is a novel BMPRII-TD-interacting protein. Upon BMP stimulation, Trb3 dissociates from BMPRII-TD and triggers degradation of Smad ubiquitin regulatory factor 1 (Smurf1), which results in the stabilization of BMP receptor-regulated Smads and potentiation of the Smad pathway. Downregulation of Trb3 inhibits BMP-mediated cellular responses, including osteoblast differentiation of C2C12 cells and maintenance of the smooth muscle phenotype of pulmonary artery smooth muscle cells. Thus, Trb3 is a critical component of a novel mechanism for regulation of the BMP pathway by BMPRII.  相似文献   
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