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Báo cáo thực tập: Vai trò của tiếng Hàn trong phát triển thị trường khách hàng Hàn Quốc tại c
Báo cáo thực tập về vai trò tiếng Hàn tại Mcnex Vina trình bày các nội dung chính sau: tuyển dụng, sản xuất, R&D. Tiếng Hàn giúp giao tiếp hiệu quả, hỗ trợ hoạt động kinh doanh & sản xuất.35 trang
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Báo cáo tổng kết đề tài nghiên cứu khoa học: Khối lượng tới hạn của sao Lùn trắng và sao Neutron
Đề tài nghiên cứu về các nội dung: những kiến thức về vật lý thống kê và thuyết tương đối liên quan đến hệ khí điện tử suy biến, quá trình cân bằng hấp dẫn của hệ khí, tìm ra biểu thức để tính khối lượng tới hạn của sao lùn trắng, thuyết tương đối rộng và nghiệm Schwarzschild cho không thời gian trong ngôi sao - nghiệm này còn có tên là nghiệm Schwarschild nội,... Để biết rõ hơn về nội dung chi tiết, mời các bạn cùng tham khảo.22 trang
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Báo cáo Y học: Two 1 : 1 binding modes for distamycin in the minor groove of d(GGCCAATTGG)
Single-crystal X-ray structure determinations of the complex between the minor-groove binder distamycin and d(GGCCAATTGG) reveal two 1 : 1 binding modes which differ in the orientation of the drug molecule in the minor groove. The two crystals were grown from different crystallization conditions and found to diffract to 2.38 and ˚ 1.85 A, respectively. The structures were refined to completion using SHELXL-93, resulting in a residual R factor of ˚ 20.30% for the 2.38-A resolution structure (including 46 ˚ water molecules) and 19.74% for the 1.85-A resolution structure (including 74 water molecules). ...10 trang
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Báo cáo Y học: Isolation, enzymatic properties, and mode of action of an exo-1,3-b-glucanase from Trichoderma viride
An exo-1,3-b-glucanase has been isolated from cultural filtrate of Trichoderma viride AZ36. The N-terminal sequence of the purified enzyme (m ¼ 61 ^ 1 kDa) showed no significant homology to other known glucanases. The 1,3-b-glucanase displayed high activity against laminarins, curdlan, and 1,3-b-oligoglucosides, but acted slowly on 1,3-1,4-b-oligoglucosides. No significant activity was detected against high molecular mass 1,3-1,4-bglucans. The enzyme carried out hydrolysis with inversion of the anomeric configuration. Whereas only glucose was released from the nonreducing terminus during hydrolysis of 1,3-b-oligoglucosides, transient accumulation of gentiobiose was observed during hydrolysis of laminarins....9 trang
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Báo cáo Y học: Soluble guanylate cyclase is allosterically inhibited by direct interaction with 2-substituted adenine nucleotides
Nitric oxide (NO), the principal endogenous ligand for soluble guanylate cyclase (sGC), stimulates that enzyme and accumulation of intracellular cGMP, which mediates many of the (patho) physiological effects of NO. Previous studies demonstrated that 2-substituted adenine nucleotides, including 2-methylthioATP (2MeSATP) and 2-chloroATP (2ClATP), allosterically inhibit guanylate cyclase C, the membrane-bound receptor for the Escherichia coli heatstable enterotoxin in the intestine. The present study examined the effects of 2-substituted adenine nucleotides on crude and purified sGC. ...8 trang
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Báo cáo Y học: Secretion of a peripheral membrane protein, MFG-E8, as a complex with membrane vesicles A possible role in membrane secretion
MFG-E8 (milk fat globule-EGF factor 8) is a peripheral membrane glycoprotein, which is expressed abundantly in lactating mammary glands and is secreted in association with fat globules. This protein consists of two-repeated EGF-like domains, a mucin-like domain and two-repeated discoidinlike domains (C-domains), and contains an integrin-binding motif (RGD sequence) in the EGF-like domain. To clarify the role of each domain on the peripheral association with the cell membrane, several domain-deletion mutants of MFG-E8 were expressed in COS-7 cells. ...10 trang
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Báo cáo Y học: Functional epitope of common c chain for interleukin-4 binding
Interleukin 4 (IL-4) can act on target cells through an IL-4 receptor complex consisting of the IL-4 receptorachain and the commoncchain (cc). An IL-4 epitope forccbinding has previously been identi®ed. In this study, thecc residues involved in IL-4 binding were de®ned by alanine-scanning mutational analysis. The epitope comprisescc residues I100, L102, and Y103 on loop EF1 together with L208 on loop FG2 as the major binding determinants.10 trang
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Báo cáo khoa học: Effects of a tryptophanyl substitution on the structure and antimicrobial activity of C-terminally truncated gaegurin 4
Gaegurin 4 (GGN4), a 37-residue antimicrobial peptide, consists of two amphipathic ahelices (residues 2–10and 16–32) connected by a flexible loop region (residues 11– 15). As part of an effort to develop new peptide antibiotics with low molecular mass, the activities of C-terminally truncated GGN4 analogues were tested. D 24)37 GGN4, a peptide analogue with 14 residues truncated from the C-terminus of GGN4, showed a complete loss of anti-microbial activity.8 trang
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Báo cáo khoa học: Action of palytoxin on apical H+/K+-ATPase in rat colon
Palytoxin stimulated a cation-dependent short-circuit cur-rent (Isc) in rat distal and proximal colon in a concen-tration-dependent fashion when applied to the mucosal surface of the tissue. The distal colon exhibited a higher sensitivity to the toxin. The palytoxin-induced Isc was blocked by vanadate but was resistant to ouabain or scilliroside, suggesting the conversion of a vanadate-sen-sitive H + /K + -ATPase into an electrogenic cation trans-porter.7 trang
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Báo cáo Y học: Assignment of molecular properties of a superactive coagulation factor VIIa variant to individual amino acid changes
Eur. J. Biochem. 269, 5950–5955 (2002) Ó FEBS 2002 doi:10.1046/j.1432-1033.2002.03323.x The most active factor VIIa (FVIIa) variants identified to date carry concurrent substitutions at positions 158, 296and 298 with the intention of generating a thrombin-mimicking motif, optionally combined with additional replacements within the protease domain [Persson, E., Kjalke, M. & Olsen, O. H. (2001)Proc. Natl Acad. Sci. USA98, 13583– 13588]. Here we have characterized variants of FVIIa mutatedat one or twoof these positions toassess the relative importance of the individual replacements. Assignment of molecular properties of a superactive coagulation factor VIIa variant to individual amino acid changes Egon Persson1 and Ole H. Olsen2 1 Haemostasis Biology and 2Medicinal Chemistry Research IV, Novo Nordisk A/S,...6 trang
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Báo cáo Y học: Structural analysis of deacylated lipopolysaccharide of Escherichia coli strains 2513 (R4 core-type) and F653 (R3 core-type)
Lipopolysaccharide (LPS) ofEscherichia colistrain2513 (R4 core-type) yielded after alkaline deacylation one major oligosaccharide by high-performance anion-exchange chro-matography (HPAEC) which had a molecular mass of 2486.59 Da as determined by electrospray ionization mass spectrometry. This was in accordance with the calculated molecular mass of a tetraphosphorylated dodecasaccharide of the composition shown below.10 trang
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Báo cáo Y học: Molecular characterization of MRG19 of Saccharomyces cerevisiae Implication in the regulation of galactose and nonfermentable carbon source utilization
We have reportedpreviously thatmultiple copies ofMRG19 suppressGALgenes inawild-typebut not inagal80strainof Saccharomyces cerevisiae. In this report we show that dis-ruption ofMRG19leads to a decrease in GALinduction whenS. cerevisiaeis inducedwith 0.02% but not with 2.0% galactose. Disruption ofMRG19in agal3background (this strainshows long-termadaptationphenotype)furtherdelays theGALinduction, supporting the notion that its function is important only under low inducing signals.11 trang
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Báo cáo khoa học: a-Fetoprotein positively regulates cytochrome c-mediated caspase activation and apoptosome complex formation
Previous results have shown that theoncoembryonicmarker a-fetoprotein (AFP) is able to induce apoptosis in tumor cells through activation of caspase 3, bypassing Fas-dependent and tumor necrosis factor receptor-dependent signaling. In this study we further investigate the molecular interactions involvedin the AFP-mediatedsignaling of apoptosis. We show that AFP treatment of tumor cells is accompaniedby cytosolic translocation of mitochondrial cytochromec. In a cell-free system, AFP mediates process-ing andactivation of caspases 3 and9 by synergistic enhancement of the low-dose cytochromec-mediated sig-nals....12 trang
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Báo cáo khoa học: Purification and characterization of NTPDase1 (ecto-apyrase) and NTPDase2 (ecto-ATPase) from porcine brain cortex synaptosomes
We purified to homogeneity and characterized NTPDase1 and NTPDase2 from porcine brain cortex synaptosomes. SDS/PAGE and immunoblotting with antibodies specific to these enzymes revealed a molecular mass estimated at 72 kDa for NTPDase1 and 66 for NTPDase2. Both enzymes exhibited kinetic properties typical for all members of the NTPDase family, e.g. low substrate specificity for tri-anddiphosphonucleosides, divalent cations dependency and insensitivity towards ATPase inhibitors.8 trang
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Báo cáo khoa học: Purification and cDNA cloning of a cellulase from abalone Haliotis discus hannai
A cellulase [endo-b-1,4-D-glucanase (EC 3.2.1.4)] was iso-lated from the hepatopancreas of abalone Haliotis discus hannaiby successive chromatographies on TOYOPEARL CM-650M, hydroxyapatite and Sephacryl S-200 HR. The molecular mass of the cellulase was estimated to be 66 000 Da by SDS/PAGE, thus the enzyme was named HdEG66. The hydrolytic activity of HdEG66 toward carb-oxymethylcellulose showed optimal temperature and pH at 38Cand 6.3, respectively.8 trang
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Báo cáo khoa học: Two CCAAT/enhancer binding protein sites in the cytochrome P4503A1 locus Potencial role in the glucocorticoid response
Induction of CYP3A genes by the ligand-activated preg-nane-X-receptor (PXR)involves the interaction of other as yet unidentified liver transcription factors. Here we show that the CYP3A1promoter contains two active sites con-trolled by the CCAAT/enhancer-binding protein a (C/ EBPa), previously shown to regulate a number of liver stress response genes. We have identified two functional C/EBP binding sites at theCYP3A1promoter that confer luciferase activity to C/EBPacotransfected CHO cells.9 trang
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Báo cáo khoa học: The resident endoplasmic reticulum protein, BAP31, associates with c-actin and myosin B heavy chain Analysis by capillary liquid chromatography microelectrospray tandem MS
BAP31 is a 28-kDa integral membrane protein of the endoplasmic reticulumwhose cytosolicdomaincontains two caspase recognition sites that are preferentially cleaved by initiator caspases,such as caspase-8. Recently,we reported that the caspase-resistant BAP31 inhibited Fas-mediated apoptotic membrane fragmentation and the release of cytochromec from mitochondria in KB epithelial cells (Nguyen M.,Breckenridge G.,Ducret A &Shore G. (2000) Mol. Cell.Biol.20,6731–6740).8 trang
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Báo cáo khoa học: Acylation of lysophosphatidylcholine plays a key role in the response of monocytes to lipopolysaccharide
Mononuclear phagocytes play a pivotal role in the pro-gression of septic shock by producing tumor necrosis factor-a(TNF-a) andother inflammatorymediators in response to lipopolysaccharide (LPS) fromGram-negativebacteria.Our previous studies have shown monocyte and macrophage activationcorrelatewithchanges inmembranephospholipid composition, mediated by acyltransferases. Interferon-c (IFN-c), which activates and primes these cells for enhanced inflammatory responses to LPS, was found to selectively activate lysophosphatidylcholine acyltransferase (LPCAT) (P...7 trang
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Chịu trách nhiệm nội dung: Nguyễn Công Hà
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Giấy phép Mạng Xã Hội số: 670/GP-BTTTT cấp ngày 30/11/2015