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排序方式: 共有1010条查询结果,搜索用时 15 毫秒
1.
Dr. Emrah Kara Dr. Nis Valentin Nielsen Bergrun Eggertsdottir Dr. Bernd Thiede Dr. Sandip M. Kanse Dr. Geir Åge Løset 《Chembiochem : a European journal of chemical biology》2020,21(13):1875-1884
We describe a novel, easy and efficient combinatorial phage display peptide substrate-mining method to map the substrate specificity of proteases. The peptide library is displayed on the pVII capsid of the M13 bacteriophage, which renders pIII necessary for infectivity and efficient retrieval, in an unmodified state. As capture module, the 3XFLAG was chosen due to its very high binding efficiency to anti-FLAG mAbs and its independency of any post-translational modification. This library was tested with Factor-VII activating protease (WT-FSAP) and its single-nucleotide polymorphism variant Marburg-I (MI)-FSAP. The WT-FSAP results confirmed the previously reported Arg/Lys centered FSAP cleavage site consensus as dominant, as well as reinforcing MI-FSAP as a loss-of-function mutant. Surprisingly, rare substrate clones devoid of basic amino acids were also identified. Indeed one of these peptides was cleaved as free peptide, thus suggesting a broader range of WT-FSAP substrates than previously anticipated. 相似文献
2.
Y Bourne B Bolgiano MP Nésa P Penfold D Johnson T Feizi C Cambillau 《Canadian Metallurgical Quarterly》1994,235(2):787-789
The soluble 14 kDa beta-galactoside-binding lectin from bovine heart, a member of the S-type lectin family, has been crystallized in a form suitable for X-ray diffraction analysis. The crystals, in the absence of a saccharide ligand, diffract beyond 2.5 A resolution. They are obtained from polyethylene glycol 6000 at pH 6.0. Crystals grow as monoclinic plates, space group P2(1), with cell dimensions: a = 35.47 A, b = 64.33 A, c = 58.78 A and beta = 91.7 degrees. The asymmetric unit contains two molecules related by a 2-fold non-crystallographic axis. Two lectin monomers in the asymmetric unit give a Vm of 2.4 A3/Da, i.e. a solvent content of approximately 50%. The complex of lectin with the saccharide ligand, N-acetyllactosamine, crystallizes in the space group P2(1)2(1)2 with cell dimensions: a = 63.55 A, b = 82.13 A and c = 62.39 A. Crystals of this complex diffract beyond 2.0 A resolution. Two complexes in the asymmetric unit lead to a Vm value of 2.8 A3/Da (57% solvent). 相似文献
3.
Carlos Conceio Antnio Luísa N. Hoffbauer 《Reliability Engineering & System Safety》2007,92(10):1353-1362
This article describes a finite element-based formulation for the statistical analysis of the response of stochastic structural composite systems whose material properties are described by random fields. A first-order technique is used to obtain the second-order statistics for the structural response considering means and variances of the displacement and stress fields of plate or shell composite structures. Propagation of uncertainties depends on sensitivities taken as measurement of variation effects. The adjoint variable method is used to obtain the sensitivity matrix. This method is appropriated for composite structures due to the large number of random input parameters. Dominant effects on the stochastic characteristics are studied analyzing the influence of different random parameters. In particular, a study of the anisotropy influence on uncertainties propagation of angle-ply composites is carried out based on the proposed approach. 相似文献
4.
The past decade has witnessed an enormous increase in our knowledge of the variety and complexity of neuropathological and neurochemical changes in Alzheimer's disease. Although the disease is characterized by multiple deficits of neurotransmitters in the brain, this overview emphasizes the structural and neurochemical localization of the elements of the acetylcholine system (choline acetyltransferase, acetylcholinesterase, and muscarinic and nicotinic acetylcholine receptors) in the non-demented brain and in Alzheimer's disease brain samples. The results demonstrate a great variation in the distribution of acetylcholinesterase, choline acetyltransferase, and the nicotinic and muscarinic acetylcholine receptors in the different brain areas, nuclei and subnuclei. When stratification is present in certain brain regions (olfactory bulb, cortex, hippocampus, etc.), differences can be detected as regards the laminar distribution of the elements of the acetylcholine system. Alzheimer's disease involves a substantial loss of the elements of the cholinergic system. There is evidence that the most affected areas include the cortex, the entorhinal area, the hippocampus, the ventral striatum and the basal part of the forebrain. Other brain areas are less affected. The fact that the acetylcholine system, which plays a significant role in the memory function, is seriously impaired in Alzheimer's disease has accelerated work on the development of new drugs for treatment of the disease of the 20th century. 相似文献
5.
6.
Ken Mattsson 《Journal of scientific computing》2003,18(1):133-153
Four different methods of imposing boundary conditions for the linear advection-diffusion equation and a linear hyperbolic system are considered. The methods are analyzed using the energy method and the Laplace transform technique. Numerical calculations are done, considering in particular the case when the initial data and boundary data are inconsistent. 相似文献
7.
Kerstin Skog Åsa Eneroth & Maria Svanberg 《International Journal of Food Science & Technology》2003,38(3):313-323
Hamburgers and chicken fillets were cooked in convection ovens, deep‐fried or contact fried and analysed for mutagenic activity using the Ames test. For the three different convection ovens, the cooking parameters studied included the presence of steam, air velocity, air temperature and holding time. For deep‐frying and contact frying, the cooking parameters included cooking temperature and cooking time. In cooked hamburgers, mutagenic activity was only detected in those that had been deep‐fried. In chicken fillets, mutagenic activity was detected in samples prepared with all cooking methods, being highest in the deep‐fried samples. Factorial analysis indicated that heat transfer was the most important factor affecting mutagenic activity. High temperature and high air velocity in the convection ovens enhanced mutagenic activity. The presence of steam reduced the mutagenic activity, except when high temperature was used in combination with high air velocity. In chicken fillets, high mutagenic activity correlated to high weight loss during cooking. Pan‐fried chicken fillets were analysed using high performance liquid chromatography (HPLC) and the mutagenic/carcinogenic heterocyclic amines 2‐amino‐3,8‐dimethylimidazo[4,5‐f ]‐quinoxaline (MeIQx), 2‐amino‐1‐methyl‐6‐phenylimidazo‐[4,5‐b]‐pyridine (PhIP) and the co‐mutagenic heterocyclic amine Norharman (9H‐pyrido[3,4‐b]‐indole) were identified. The HPLC fractions were tested for mutagenic activity and, apart from the mutagenic fractions corresponding to MeIQx and PhIP, several mutagenic fractions were detected that did not correspond to known heterocyclic amines. 相似文献
8.
K Andersson E Stadberg LA Mattsson G Rybo G Samsioe 《Canadian Metallurgical Quarterly》1996,41(5):476-483
Electrical stimulation of the basal temporal region of the dominant hemisphere before partial temporal lobectomy for epilepsy sometimes produces temporary interruption of language function, but the significance of removal of this area is unknown. We evaluated the correlation between resection of the basal temporal language areas (BTLA) and certain types of postoperative language deficits. In a population of 25 patients, we mapped the inferolateral temporal lobe with cortical electrical stimulation, verifying the positions of the stimulating electrodes with three-dimensional computed tomography (CT). Eighty percent of the patients developed transient language deficits with stimulation, particularly with tests of confrontation naming and comprehension. BTLA was primarily located in the fusiform gyrus, from 1 to 9 cm from the temporal tip. At testing 6-12 months after operation, patients with BTLA resection performed worse (mean 9% decrease) than those with no BTLA resection (mean 4% improvement) on tests of confrontation naming (p = 0.03). Resection size accounted for less of the variance in decrease in confrontation naming than did resection of the BTLA. Tests of performance I.Q. (PIQ), verbal I.Q. (VIQ), or recognition memory for word and verbal learning showed no significant difference between these groups. Most patients do not have language decrease with removal of basal temporal lobe 5-6 cm from the tip, even with removal of BTLA. Some patients, however, have persistent decrease in naming. 相似文献
9.
Luccas M. Barata Eloísa H. Andrade Alessandra R. Ramos Oriel F. de Lemos William N. Setzer Kendall G. Byler Jos Guilherme S. Maia Joyce Kelly R. da Silva 《International journal of molecular sciences》2021,22(2)
This study evaluated the chemical compositions of the leaves and fruits of eight black pepper cultivars cultivated in Pará State (Amazon, Brazil). Hydrodistillation and gas chromatography–mass spectrometry were employed to extract and analyze the volatile compounds, respectively. Sesquiterpene hydrocarbons were predominant (58.5–90.9%) in the cultivars “Cingapura”, “Equador”, “Guajarina”, “Iaçará”, and “Kottanadan”, and “Bragantina”, “Clonada”, and “Uthirankota” displayed oxygenated sesquiterpenoids (50.6–75.0%). The multivariate statistical analysis applied using volatile composition grouped the samples into four groups: γ-Elemene, curzerene, and δ-elemene (“Equador”/“Guajarina”, I); δ-elemene (“Iaçará”/“Kottanadan”/“Cingapura”, II); elemol (“Clonada”/“Uthirankota”, III) and α-muurolol, bicyclogermacrene, and cubebol (“Bragantina”, IV). The major compounds in all fruit samples were monoterpene hydrocarbons such as α-pinene, β-pinene, and limonene. Among the cultivar leaves, phenolics content (44.75–140.53 mg GAE·g−1 FW), the enzymatic activity of phenylalanine-ammonia lyase (20.19–57.22 µU·mL−1), and carotenoids (0.21–2.31 µg·mL−1) displayed significant variations. Due to black pepper’s susceptibility to Fusarium infection, a molecular docking analysis was carried out on Fusarium protein targets using each cultivar’s volatile components. F. oxysporum endoglucanase was identified as the preferential protein target of the compounds. These results can be used to identify chemical markers related to the susceptibility degree of black pepper cultivars to plant diseases prevalent in Pará State. 相似文献
10.
Different routes for immobilization of TiO2 on conducting substrates were compared to find active and stable photocatalysts, which could either be operated in open circuit (photocatalysis) or with applied electric potential (photoelectrocatalysis). The advantage of applying an electric potential was investigated. Polarization curves and photoelectrochemical degradation reactions served to characterize catalysts and to find a way of predicting the optimum synthesis conditions. The difference between front side (EE) and back side (SE) illumination is discussed as a function of layer thickness, as well as the influence of oxidizable substance concentration on photocurrents. Stability of catalysts was investigated in repetitive degradation experiments. 相似文献