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991.
Kong Tao Zhang Shu-Hui Zhang Cai Zhang Ji-Liang Yang Fan Wang Guo-Yong Yang Zi-Jun Bai Dong-Ying Shi Yun-Yun Liu Tian-Qi Li Hai-Long 《Biological trace element research》2020,194(2):443-443
Biological Trace Element Research - The original version of this article unfortunately contained a mistake. The correct title should be “The Effects of 50 nm Unmodified Nano-ZnO on Lipid... 相似文献
992.
Biocatalytic desulfurization of diesel oil in an air-lift reactor with immobilized Gordonia nitida CYKS1 cells 总被引:1,自引:0,他引:1
A new type of air-lift reactor with immobilized Gordonia nitida CYKS1 cells on a fibrous support was designed and used for the biocatalytic desulfurization (BDS) of diesel oil. Its performance was evaluated at different phase ratios of the oil to the aqueous medium (or oil phase fractions) and different sucrose concentrations. When the reaction mixture contained 10% diesel oil (v/v), 61-67% of sulfur was removed as the sulfur content decreased from 202-250 to 76-90 mg L(-1) in 72 h. The sulfur content did not decrease any further because the remaining sulfur compounds were recalcitrant to BDS. During the desulfurization, the strain CYKS1 consumed hydrocarbons in the diesel oil, mainly n-alkanes with 10-26 carbons, as carbon source even though an easily available carbon source, sucrose, was supplied. 相似文献
993.
丝孢酵母高甲硫氨酸突变株的选育及营养调控 总被引:4,自引:0,他引:4
以丝孢酵母(Trichosporon Behr)ST851为原始菌株,经紫外线诱变,在含乙硫氨酸的双层平板上筛选到多株抗乙硫氨酸突变株。其中ST851-10株抗乙硫氨酸浓度达到350μg/ml,其菌体蛋白质含量由40.5%提高到44.3%,菌体甲硫氨酸含量由20.45mg/g-DCW增加到29.32mg/g-DCW。在以苹果渣为碳源、尿素为氮源、硫酸镁作硫源的最适培养条件下,固态发酵24h后,蛋白质和甲硫氨酸含量较原始菌株分别提高了15.8%和44.9%。培养基中C/N值低有利于甲硫氨酸的合成,C/N值高则适合于菌体生长。在苹果渣固态发酵过程中,适当补加氮源既有利于菌体生长和甲硫氨酸的合成,又可起到调节培养基pH值的作用。 相似文献
994.
Guang‐Zhen Jin Su‐Jin Cho Young‐S Lee Myeong‐Ok Kim Dong‐Woo Cho Il‐Keun Kong 《Cell biology international》2010,34(1):135-140
MSCs (mesenchymal stem cells) derived from the bone marrow have shown to be a promising source of stem cells in a therapeutic strategy of neurodegenerative disorder. Also, MSCs can enhance the TH (tyrosine hydroxylase) expression and DA (dopamine) content in catecholaminergic cells by in vitro co‐culture system. In the present study, we investigated the effect of intrastriatal grafts of MSCs on TH protein and gene levels and DA content in adult intact rats. When MSCs were transplanted into the striatum of normal rats, the grafted striatum not only had significantly higher TH protein and mRNA levels, but also significantly higher DA content than the untransplanted striatum. Meanwhile, the grafted MSCs differentiated into neurons, astrocytes and oligodendrocytes; however, TH‐positive cells could not be detected in our study. These experimental results offer further evidence that MSCs are a promising candidate for treating neurodegenerative diseases such as Parkinson's disease. 相似文献
995.
The freshwater genus Hyalella Smith, 1874 has a distribution restricted to the Western Hemisphere with most species being found in South America. In this report we describe a new species of Hyalella from the Atlantic Forest of the Misiones province, Argentina. 相似文献
996.
Olamendi-Portugal T García BI López-González I Van Der Walt J Dyason K Ulens C Tytgat J Felix R Darszon A Possani LD 《Biochemical and biophysical research communications》2002,299(4):562-568
This report describes the isolation, primary structure determination, and functional characterization of two similar toxins from the scorpion Parabuthus granulatus named kurtoxin-like I and II (KLI and KLII, respectively). KLII from P. granulatus is identical to kurtoxin from Parabuthus transvaalicus (a 63 amino-acid long toxin) whereas KLI is a new peptide containing 62 amino acid residues closely packed by four disulfide bridges with a molecular mass of 7244. Functional assays showed that both toxins, KLI and kurtoxin from P. granulatus, potently inhibit native voltage-gated T-type Ca(2+) channel activity in mouse male germ cells. In addition, KLI was shown to significantly affect the gating mechanisms of recombinant Na(+) channels and weakly block alpha(1)3.3Ca(V) channels expressed in Xenopus oocytes. KLI and kurtoxin from P. granulatus represent new probes to study the role of ion channels in germ cells, as well as in cardiac and neural tissue. 相似文献
997.
998.
Zhou CZ Meyer P Quevillon-Cheruel S Li De La Sierra-Gallay I Collinet B Graille M Blondeau K François JM Leulliot N Sorel I Poupon A Janin J Van Tilbeurgh H 《Protein science : a publication of the Protein Society》2005,14(1):209-215
We determined the three-dimensional crystal structure of the protein YML079wp, encoded by a hypothetical open reading frame from Saccharomyces cerevisiae to a resolution of 1.75 A. The protein has no close homologs and its molecular and cellular functions are unknown. The structure of the protein is a jelly-roll fold consisting of ten beta-strands organized in two parallel packed beta-sheets. The protein has strong structural resemblance to the plant storage and ligand binding proteins (canavalin, glycinin, auxin binding protein) but also to some plant and bacterial enzymes (epimerase, germin). The protein forms homodimers in the crystal, confirming measurements of its molecular mass in solution. Two monomers have their beta-sheet packed together to form the dimer. The presence of a hydrophobic ligand in a well conserved pocket inside the barrel and local sequence similarity with bacterial epimerases may suggest a biochemical function for this protein. 相似文献
999.
Zhu S Zhang Q Gudise C Meng L Wei L Smith E Kong Y 《Bioorganic & medicinal chemistry letters》2007,17(22):6101-6106
Primaquine is the drug of choice for the radical cure of Plasmodium vivax malaria, but possesses serious side effects. In this study novel primaquine analogues were designed and synthesized. Lower toxicity was achieved by reducing or eliminating the tendency of forming chemically reactive and toxic intermediates and metabolites. In vitro and in vivo studies found that synthesized compounds were less toxic than the parent compound primaquine, while preserving the desired antimalarial activity. Some of these compounds possess a therapeutic index over 10 times superior to that of the commonly used antimalarial drug chloroquine. These compounds, as well as the underlying design rationale, may find usefulness in the discovery and development of new antimalarial drugs. 相似文献
1000.