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31.
32.
Nm23 is a family of genes encoding the nucleoside diphosphate (NDP) kinase, which functions in a wide variety of biological processes, including growth, development, differentiation and tumor metastasis. In this study, a novel nm23 gene, designated as Mrnm23, was identified from the freshwater giant prawn Macrobrachium rosenbergii. The full-length cDNA was 776 bp in length, encoding for a protein of 176 amino acids with one typical NDP kinase domain that harbored all the crucial residues for nucleotide binding and enzymatic activity. Like human novel nm23-H1B, the putative protein contained a unique 21-amino-acid NH2-terminal extension as compared to human nm23 (nm23-H1) homologs. Further, 3 extra amino acid residues prolonged the COOH-terminus. The Mrnm23 was ubiquitously expressed in all tissues examined, including androgenic gland, gill, heart, liver, muscle, ovary, and testis. In situ hybridization to gonad sections indicated that the Mrnm23 mRNA was localized in the cytoplasm of cup-base of differentiating spermatids, in the spike of the umbrella-shaped spermatozoa and in the cytoplasm of the early previtellogenic oocytes, suggesting that the Mrnm23 has potential roles in spermiogenesis and early differentiation of oocyte. 相似文献
33.
Bengt Steen 《The International Journal of Life Cycle Assessment》2007,12(2):103-108
Goal, Scope and Background The life cycles of many products including textiles contain chemicals for which process flow data are not known or are too
time consuming to collect. Although each chemical may not contribute significantly to the LCA results of the product, which
might justify excluding them, but together their contribution could be significant. Similarly, rough estimates of the process
flows for the production of a single chemical may be very uncertain and considered meaningless, while the estimates of the
cumulative data of process flows for several chemicals may be less uncertain and be a meaningful contribution to the quality
of the LCA results. There are methods for estimation of process flows for different types of products, with varying demands
regarding input data and time and with varying accuracy of the results. This work contributes to the available methods, focusing
on simple estimations for production of chemical substances. The goal was to create a fast method for estimation of emissions,
resource and energy flows (process flows) for the production of chemicals, based on easily available data on the properties
of the chemicals. The process flows investigated were limited to those normally associated with process industries and contributing
most to depletion of resources, to global warming, acidification, eutrophication and photochemical ozone production, i.e.
use of energy, crude oil, coal, natural gas, uranium in ore and emissions of CO2, SOx, NOx, NMVOC, methane, BOD, COD and total
N. Toxic substances were excluded, since toxic emissions are substance specific and cannot be included in a generalization.
Method Available data for the process flows for the production of chemicals of mainly fossil origin were correlated to properties
of chemicals such as amount of carbon in the molecule, heat of formation and average number of chemical reaction steps in
the production. The production procedures were found in readily available literature. Up to about six reaction steps were
evaluated in the correlation study. The variations in the process flows among the chemicals studied were calculated.
Results and Discussion There were weak correlations between average number of chemical reaction steps in the production and energy use, COD measured
in water emissions, and SOx and NOx emissions to air. For the remaining properties of chemicals and process flows, there were
only weak correlations for share of double bonding in the molecule if only molecules containing double bondings were included.
Conclusions The precision in estimation of the process flows increases non-significantly when adding information on the number of reaction
steps or share of double bonding for chemicals containing double bonding is added.
Recommendations and Outlook It seems reasonable to start with a simple grouping method to estimate the process flows for the production of a chemical
of fossil origin. Further investigations might investigate whether there is a correlation between process flows and the costs
of chemicals, and further study the correlations between process flows and share of double bonding for chemicals containing
double bondings. 相似文献
34.
Except for its redox properties, cytochrome c is an inert protein. However, dissociation of the bond between methionine-80 and the heme iron converts the cytochrome into a peroxidase. Dissociation is accomplished by subjecting the cytochrome to various conditions, including proteolysis and hydrogen peroxide (H2O2)-mediated oxidation. In affected cells of various neurological diseases, including Parkinson's disease, cytochrome c is released from the mitochondrial membrane and enters the cytosol. In the cytosol cytochrome c is exposed to cellular proteases and to H2O2 produced by dysfunctional mitochondria and activated microglial cells. These could promote the formation of the peroxidase form of cytochrome c. In this study we investigated the catalytic and cytolytic properties of the peroxidase form of cytochrome c. These properties are qualitatively similar to those of other heme-containing peroxidases. Dopamine as well as sulfhydryl group-containing metabolites, including reduced glutathione and coenzyme A, are readily oxidized in the presence of H2O2. This peroxidase also has cytolytic properties similar to myeloperoxidase, lactoperoxidase, and horseradish peroxidase. Cytolysis is inhibited by various reducing agents, including dopamine. Our data show that the peroxidase form of cytochrome c has catalytic and cytolytic properties that could account for at least some of the damage that leads to neuronal death in the parkinsonian brain. 相似文献
35.
新疆干旱区盐碱地生态治理关键技术研究 总被引:13,自引:3,他引:13
现阶段新疆干旱区高强度水土资源开发,致使传统灌排水盐平衡模式难于维继;高效节水灌溉技术应用改变农田土壤水盐运移规律,需要创新调控理论与技术体系;传统盐碱地农业开发利用模式资源效率低、维持成本高,需要以生物修复技术为核心构建盐碱地高效率资源化利用模式。针对上述问题,在国家重点研发计划(2016YFC0501400)的资助下,通过机理研究、关键技术研发、产品研制、县域集成示范实现:(1)建立新疆干旱区现代水盐平衡调控理论,(2)创新干旱区盐碱地生态治理模式,(3)建成盐碱地产业化集成示范区,形成全产业链的盐碱地生态治理技术服务体系,(4)稳定一支以新疆相关单位为主体,国内优势单位参与的根植新疆的盐碱地生态治理队伍。 相似文献
36.
Dmrt1 has been suggested to play significant roles in sex determination and differentiation, but various expression patterns and cell types have been observed in the testis of vertebrates. Polyploid gibel carp, because of the multiple modes of unisexual gynogenesis and sexual reproduction, has become a unique case to explore the evolution of sex determination and differentiation. However, the sex-determination related genes in gibel carp have remained unknown. In this study, we identified and characterized 4 cDNAs of Dmrt1 genes. Subsequently, a polyclonal antibody specific to CagDMRT1 was prepared to examine its expression and distribution patterns at protein level. Significantly, both relative real-time PCR and Western blot detection confirmed predominant expression of CagDmrt1 in the adult testis of gibel carp. Moreover, the intensive expression of CagDMRT1 around spermatogenic cysts was revealed during spermatogenesis. And, following immunofluorescence co-localization of CagDMRT1 and CagVASA, a prominent CagDMRT1 expression in Sertoli cells and a mild CagDMRT1 expression in spermatogenic cells including spermatogonia and primary spermatocytes were clearly characterized. The CagDMRT1 signal in Sertoli cells is extensively distributed in both nuclei and cytoplasm, while the CagDMRT1 in spermatogonia and primary spermatocytes is mainly expressed in nuclei, and there is only the remained CagDMRT1 signal in the cytoplasm of secondary spermatocytes. These findings suggest that DMRT1 should be related to testis differentiation and spermatogenesis in gibel carp. 相似文献
37.
38.
39.
冀东地区西伯利亚白刺开发利用价值研究 总被引:1,自引:0,他引:1
西伯利亚白刺是华北沿海地区仅有的一个白剌种,在冀东滨海地区有一定的野生群落分布。研究结果表明,西伯利亚白刺具有极强的耐盐能力,0—50cm土体平均全盐含量最高达到1.97%,极端最高值达到3.99%。其果汁含有非常丰富的维生素C,高达444.07mg/100g,仅次于酸枣,排在各类蔬菜、水果的第二位,是开发功能饮料的上好原料。果实成熟后的嫩茎叶含粗蛋白28.80%,粗纤维8.86%,粗脂肪2.24%,是优质的饲料。种子脂肪含量17.2%,其中油酸含量25.02%,亚油酸含量69.02%,是生产优质保健食用油的好原料。所以,西伯利亚白刺是开发利用重盐碱地和沿海滩涂的优良植物,极具开发价值。 相似文献
40.
Alvarez AH Martinez-Cadena G Silva ME Saavedra E Avila EE 《Experimental parasitology》2007,117(4):349-356
In addition to its classic glycolytic role, glyceraldehyde-3-phosphate dehydrogenase (GAPDH) has been implicated in many activities unrelated to glycolysis, such as membrane fusion, binding to host proteins and signal transduction. GAPDH can be the target of several modifications that allow incorporation to membranes and possible regulation of its activity; among these modifications is mono-ADP-ribosylation. This post-translational modification is important for the regulation of many cellular processes and is the mechanism of action of several bacterial toxins. In a previous study, we observed the extracellular ADP-ribosylation of a 37-kDa ameba protein. We report here that GAPDH and cysteine synthase A are the main ADP-ribosylated proteins in Entamoeba histolytica extracellular medium, GAPDH is secreted from ameba at 37 degrees C in a time-dependent manner, and its enzymatic activity is not inhibited by ADP-ribosylation. Extracellular GAPDH from ameba may play an important role in the survival of this human pathogen or in interaction with host molecules, as occurs in other organisms. 相似文献