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951.
Araki Shigeru; Oohusa Tuyoshi; Omata Tatsuo; Murata Norio 《Plant & cell physiology》1984,25(5):841-843
Chlorophyllide a, pheophorbide a, chlorophyll a and pheophytina were separated in a short time by anion-exchange chromatographywith a short column of DEAE-Sepharose CL-6B. (Received February 16, 1984; Accepted April 13, 1984) 相似文献
952.
An apparent seasonal change in the cold-lability of pyruvateorthophosphate dikinase was observed in Panicum maximum thatsuggests a climatic change in the amount of the factor(s) whichprotects the enzyme against cold-inactivation. This factor(s)was partially characterized as a large molecule(s) with a heat-labilemoiety essential for its function. (Received May 23, 1984; Accepted July 25, 1984) 相似文献
953.
Noschang Cristie Grazziotin Krolow Rachel Pettenuzzo Leticia Ferreira Ávila Mônica Colpini Fachin Andrelisa Arcego Danusa von Pozzer Toigo Eduardo Crema Leonardo Machado Diehl Luísa Amália Vendite Deusa Dalmaz Carla 《Neurochemical research》2010,35(4):677-677
Neurochemical Research - 相似文献
954.
Hideaki Togashi Takayuki Nara Chisato Sekikawa Masayuki Kawakami Nakatsugu Yaginuma Tatsuo Tsunoda Kengo Sakaguchi Fujio Mizukami 《Biotechnology progress》2009,25(1):200-206
We used zeolite beta as an adsorbing matrix to refold recombinant lactate dehydrogenase (LDH) protein collected as an insoluble aggregate from a bacterial expression system. The adsorption isotherm revealed that 1 g of zeolite adsorbed 200 mg of denatured LDH solubilized with a buffer containing 6 M of guanidine hydrochloride. The pH of the buffer had little effect on the adsorption, but this property was abolished by preincubation of the zeolite with polyethylene glycol (PEG) in a weight ratio of 1:10. These data suggest that the adsorption of LDH depends on the hydrophobicity of the zeolite surface, and that the adsorption of PEG to zeolite is sufficient to release LDH from its surface. LDH was thus released by refolding buffer containing PEG and arginine, and soluble LDH was obtained in its active enzymatic form. The addition of arginine dramatically increased the yield of LDH in a dose‐dependent manner. The overall refolding efficiency was optimized to 35%. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 相似文献
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Jorge Cano Miguel Angel Descalzo Nicolás Ndong-Mabale Pedro Ndong-Asumu Leonardo Bobuakasi Sisinio Nzambo-Ondo Agustín Benito Jesús Roche 《Journal of vector ecology》2007,32(2):218-225
The aim of this study was to predict the distribution and movement of populations of the tsetse fly, Glossina palpalis palpalis (Diptera: Glossinidae), in the wet and dry seasons and to analyze the impact of the use of mono-pyramidal traps on fly populations in the Kogo focus in 2004 and 2005. Three Glossina species are present in Kogo: Glossina palpalis palpalis, major HAT vector in West-Central Africa, Glossina caliginea, and Glossina tabaniformis. The apparent density (AD) of G. p. palpalis clearly fell from 1.23 tsetse/trap/day in July 2004 to 0.27 in December 2005. A significant reduction in the mean AD for this species was noted between seasons and years. The diversity of Glossina species was relatively low at all the sampling points; G. p. palpalis clearly predominated over the other species and significantly dropped as a consequence of control activities. The predictive models generated for the seasonal AD showed notable differences not only in the density but in the distribution of the G. p. palpalis population between the rainy and dry season. The mono-pyramidal traps have proven to be an effective instrument for reducing the density of the tsetse fly populations, although given that the Kogo trypanosomiasis focus extends from the southern Equatorial Guinea to northern Gabon, interventions need to be planned on a larger scale, involving both countries, to guarantee the long-term success of control. 相似文献
958.
Yoshihiro Takasuga Toshiwo Andoh Jinpei Yamashita Tatsuo Yagura 《Experimental cell research》1995,217(2)
A bis(2,6-dioxopiperazine) derivative, ICRF-193, is a specific inhibitor of topoisomerase II without clearable complex-stabilizing activity. In Xenopus egg extract containing ICRF-193, demembranated sperm head chromatins were inhibited from decondensation. However, nuclear envelope-lamina assembled on the inhibited chromatins. The nuclear envelope-lamina continued to expand even after loss of contact with the chromatin surface. On the other hand, semiconservative DNA replication was initiated as soon as the lamina was assembled onto the surface of condensed chromatin, though the initiation was retarded and its extent was reduced, compared with that in noninhibited chromatins. Thus, it is concluded that topoisomerase II activity is not required for the formation of active DNA replication clusters and the extension of nuclear envelope-lamina on the chromatin, while the nuclear envelope-mediated decondensation of sperm chromatins is dependent on topoisomerase II activity. 相似文献
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Sánchez María Laura Schiaffino María Romina Graziano Martín Huber Paula Lagomarsino Leonardo Minotti Priscilla Zagarese Horacio Izaguirre Irina 《Aquatic Ecology》2021,55(2):417-435
Aquatic Ecology - The Salado River basin, Buenos Aires, Argentina, contains numerous permanent shallow lakes under anthropic pressure due to different land uses/land covers (LULC) in their... 相似文献