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71.
研究得知湘南地区引进沾化冬枣、梨枣和骏枣的枣头一次枝(下简称枣头)伸长生长节律与本地品种鸡蛋枣相似,幼树期枣头有两次明显的伸长生长过程,其间出现生长暂缓期。从枣头年生长量看,三个引进品种均比本地品种鸡蛋枣要小,但秋季生长量比重均比鸡蛋枣还要大。三个引进品种果实均较鸡蛋枣大,果实生长规律均与鸡蛋枣相似。但各个品种果实生育期均长于鸡蛋枣。冬枣果实生育期最长为100天~110天,梨枣与骏枣果实生育较短,梨枣70天~75天,骏枣约85天,而鸡蛋枣只有65天~70天。 相似文献
72.
Alzheimer's disease is characterized by progressive loss of neurons accompanied by the formation of intraneural neurofibrillary tangles and extracellular amyloid plaques. Human neuronal growth inhibitory factor, classified as metallothionein-3 (MT-3), was found to be related to the neurotrophic activity promoting cortical neuron survival and dendrite outgrowth in the cell culture studies. We have determined the solution structure of the alpha-domain of human MT-3 (residues 32-68) by multinuclear and multidimensional NMR spectroscopy in combination with the molecular dynamic simulated annealing approach. The human MT-3 shows two metal-thiolate clusters, one in the N-terminus (beta-domain) and one in the C-terminus (alpha-domain). The overall fold of the alpha-domain is similar to that of mouse MT-3. However, human MT-3 has a longer loop in the acidic hexapeptide insertion than that of mouse MT-3. Surprisingly, the backbone dynamics of the protein revealed that the beta-domain exhibits similar internal motion to the alpha-domain, although the N-terminal residues are more flexible. Our results may provide useful information for understanding the structure-function relationship of human MT-3. 相似文献
73.
柴达木盆地西伯利亚白刺和唐古特白刺的氨基酸含量及其营养评价 总被引:17,自引:0,他引:17
对柴达木盆地的西伯利亚白刺和唐古特白刺不同部位中氨基酸含量作了分析比较 ,并进行了营养评价。白刺中富含蛋白质 ,含有 18种氨基酸 ,其中有人体必需的 8种氨基酸 ,白刺果汁中的必需氨基酸含量远高于沙棘果汁。两种白刺的蛋白质和各氨基酸在各部位中含量分布相似 ,但因种的差异 ,第一限制性氨基酸稍有差别。 相似文献
74.
Zameer A Kasturirangan S Emadi S Nimmagadda SV Sierks MR 《Journal of molecular biology》2008,384(4):917-928
The Amyloid-β (Aβ) peptide is a major component of the amyloid plaques associated with Alzheimer's disease (AD). Recent studies suggest that the most toxic forms of Aβ are small, soluble oligomeric aggregates. Here, we report the isolation and characterization of a single-chain variable domain (scFv) antibody isolated against oligomeric Aβ using a protocol developed in our laboratory that combines phage display technology and atomic force microscopy (AFM). Starting with a randomized, single framework phage display library, after three rounds of selection against oligomeric Aβ, we identified an scFv that bound oligomeric Aβ specifically, but not monomeric or fibrillar forms. The anti-oligomeric scFv inhibits Aβ aggregation and toxicity, and reduces the toxicity of preformed oligomeric Aβ towards human neuroblastoma cells. When used to probe samples of human brain tissue, the scFv reacted with AD tissue but not a healthy control or Parkinson's disease brain samples. The anti-oligomeric Aβ scFv therefore has potential therapeutic and diagnostic applications in specifically targeting or identifying the toxic morphologies of Aβ in AD brains. 相似文献
75.
H. Seelert D.N. Dani T. Hauß F. Krause M. Frenzel S. Rexroth H.J. Schwaßmann J. Vonck 《BBA》2009,1787(6):657-429
By the elucidation of high-resolution structures the view of the bioenergetic processes has become more precise. But in the face of these fundamental advances, many problems are still unresolved. We have examined a variety of aspects of energy-transducing membranes from large protein complexes down to the level of protons and functional relevant picosecond protein dynamics. Based on the central role of the ATP synthase for supplying the biological fuel ATP, one main emphasis was put on this protein complex from both chloroplast and mitochondria. In particular the stoichiometry of protons required for the synthesis of one ATP molecule and the supramolecular organisation of ATP synthases were examined. Since formation of supercomplexes also concerns other complexes of the respiratory chain, our work was directed to unravel this kind of organisation, e.g. of the OXPHOS supercomplex I1III2IV1, in terms of structure and function. Not only the large protein complexes or supercomplexes work as key players for biological energy conversion, but also small components as quinones which facilitate the transfer of electrons and protons. Therefore, their location in the membrane profile was determined by neutron diffraction. Physico-chemical features of the path of protons from the generators of the electrochemical gradient to the ATP synthase, as well as of their interaction with the membrane surface, could be elucidated by time-resolved absorption spectroscopy in combination with optical pH indicators. Diseases such as Alzheimer's dementia (AD) are triggered by perturbation of membranes and bioenergetics as demonstrated by our neutron scattering studies. 相似文献
76.
The first finding of the hydromedusa Hydractinia minima (Trinci, 1903) in plankton of Peter the Great Bay (Sea of Japan) is reported. The hydromedusae are 0.24–0.51 mm in bell diameter and 0.25–0.53 mm in height. The size characteristics of the nematocysts of this species (desmonemes and microbasic euryteles) are given. H. minima is present in the plankton of Peter the Great Bay from June through October at water temperatures of 16.4 to 22°C with the highest mean monthly density of 151 ind./m3. The finding of H. minima in Peter the Great Bay extends the area of this species in the North Pacific to the low-boreal subzone.Original Russian Text Copyright © 2005 by Biologiya Morya, Chaplygina, Dautova. 相似文献
77.
Dobrian AD Lieb DC Cole BK Taylor-Fishwick DA Chakrabarti SK Nadler JL 《Progress in lipid research》2011,50(1):115-131
The 12/15-lipoxygenase enzymes react with fatty acids producing active lipid metabolites that are involved in a number of significant disease states. The latter include type 1 and type 2 diabetes (and associated complications), cardiovascular disease, hypertension, renal disease, and the neurological conditions Alzheimer’s disease and Parkinson’s disease. A number of elegant studies over the last thirty years have contributed to unraveling the role that lipoxygenases play in chronic inflammation. The development of animal models with targeted gene deletions has led to a better understanding of the role that lipoxygenases play in various conditions. Selective inhibitors of the different lipoxygenase isoforms are an active area of investigation, and will be both an important research tool and a promising therapeutic target for treating a wide spectrum of human diseases. 相似文献
78.
Dentex ( Cheimerius ) canariensis is recorded for the first time for European waters, on the basis of four specimens captured on the coast of Cádiz (SW Iberian peninsula). 相似文献
79.
Hu ZH Wang XC Li LY Liu ML Liu R Ling Z Tian Q Tang XW Wu YG Wang JZ 《Acta biochimica et biophysica Sinica》2004,36(12):803-810
Memory impairment is usually the early and most promi-nent clinical manifestation of Alzheimer disease (AD), aprogressive neurodegenerative illness characterized bygradual deposition of neuritic plaques and neurofibrillarytangles in the brain of the patie… 相似文献
80.
Wiltfang J Esselmann H Bibl M Smirnov A Otto M Paul S Schmidt B Klafki HW Maler M Dyrks T Bienert M Beyermann M Rüther E Kornhuber J 《Journal of neurochemistry》2002,81(3):481-496
Human lumbar CSF patterns of Abeta peptides were analysed by urea-based beta-amyloid sodium dodecyl sulphate polyacrylamide gel electrophoresis with western immunoblot (Abeta-SDS-PAGE/immunoblot). A highly conserved pattern of carboxyterminally truncated Abeta1-37/38/39 was found in addition to Abeta1-40 and Abeta1-42. Remarkably, Abeta1-38 was present at a higher concentration than Abeta1-42, being the second prominent Abeta peptide species in CSF. Patients with Alzheimer's disease (AD, n = 12) and patients with chronic inflammatory CNS disease (CID, n = 10) were differentiated by unique CSF Abeta peptide patterns from patients with other neuropsychiatric diseases (OND, n = 37). This became evident only when we investigated the amount of Abeta peptides relative to their total Abeta peptide concentration (Abeta1-x%, fractional Abeta peptide pattern), which may reflect disease-specific gamma-secretase activities. Remarkably, patients with AD and CID shared elevated Abeta1-38% values, whereas otherwise the patterns were distinct, allowing separation of AD from CID or OND patients without overlap. The presence of one or two ApoE epsilon4 alleles resulted in an overall reduction of CSF Abeta peptides, which was pronounced for Abeta1-42. The severity of dementia was significantly correlated to the fractional Abeta peptide pattern but not to the absolute Abeta peptide concentrations. 相似文献