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Distribution of echinococcosis/hydatidosis in Italy 总被引:1,自引:0,他引:1
Results of an epidemiological survey carried out in 88 slaughterhouses in Italy from 1979 to 1983 are reported. Data have been compared to national surveys previously conducted in 1955 and from 1968 to 1978. Analysis of various factors affecting the incidence of the disease in different areas of the country are reported. 相似文献
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A comparative study of some properties of cytidine deaminase from Escherichia coli and chicken liver 总被引:1,自引:0,他引:1
A Vita T Cacciamani P Natalini S Ruggieri N Raffaelli G Magni 《Comparative biochemistry and physiology. B, Comparative biochemistry》1989,93(3):591-594
The molecular and kinetic properties of cytidine deaminase from E. coli and chicken liver show several interesting differences and similarities: 1. Both enzymes possess an oligomeric structure, and linear kinetics. 2. The chicken liver enzyme is strictly dependent on the presence of reducing agents and presents a microheterogeneity in the pure preparation. 3. Both enzymes display identical specificity and share a rapid-equilibrium random Uni-Bi mechanism of catalysis. 4. The chicken liver enzyme is inhibited competitively by dTTP, CMP and dCMP. 相似文献
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Massimo Aureli Maura Samarani Nicoletta Loberto Elena Chiricozzi Laura Mauri Sara Grassi Domitilla Schiumarini Alessandro Prinetti Sandro Sonnino 《Glycoconjugate journal》2018,35(4):397-402
Sphingolipid metabolism is an intricate network of several interdependent and co-regulated pathways. In addition to the mainstream biosynthetic and catabolic pathways, several processes, even if less important in contributing to the final tissue sphingolipid composition from the quantitative point of view, might become relevant when sphingolipid metabolism is for any reason dysregulated and concur to the onset of neuronal pathologies. The main subcellular sites involved in the mainstream metabolic pathway are represented by the Golgi apparatus (for the biosynthesis) and by the lysosomes (for catabolism). On the other hand, the minor collateral pathways are associated with the plasma membrane and membranes of other organelles, and likely play important roles in the local regulation of membrane dynamics and contribute to maintain a perfect membrane organization functional to the physiology of the cell. In this review, we will consider few aspects of the sphingolipid metabolic pathway depending by the dynamic of the membranes that seems to become relevant in neurodegenerative diseases. 相似文献
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Francesca Zambianchi Stefano Raimondi Piero Pasta Giacomo Carrea Nicoletta Gaggero John M. Woodley 《Journal of Molecular Catalysis .B, Enzymatic》2004,31(4-6):165-171
Both whole cells of recombinant Escherichia coli TOP10, overexpressing cyclohexanone monooxygenase (CHMO) and isolated cyclohexanone monooxygenase, were used to carry out the enantioselective oxidation of 1,3-dithiane (1) to (R)-1,3-dithiane-1-oxide (2). The two biocatalysts were evaluated under various experimental conditions (e.g., shaken flask or bioreactor; non-bound or resin-adsorbed substrate; different substrate concentrations) in terms of volumetric productivity and enantioselectivity. While productivity was similar in the two cases (up to 0.58 g L−1 h−1), the optical purity of the product was much higher with the isolated enzyme (up to 98% e.e.) than with the whole cell biocatalyst (up to 85% e.e.). 相似文献