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891.
892.
M C Contreras L Sandoval P Salinas P Mu?oz S Vargas 《Boletín chileno de parasitología》2000,55(1-2):17-24
Toxoplasmosis, a world-wide zoonotic infection, is generally asymptomatic and benign in immunocompetent individuals, but it can be serious in immunodeficiencies particularly in patients with acquired immunodeficiency syndrome and in children infected in utero. So, it is important to dispose methods which permit discriminate between recent and chronic infections. In order to contribute to improve the diagnosis of toxoplasmosis ELISA IgG, IgM, IgA and ELISA IgG avidity were performed in 15 and 24 sera from patients suspected of having acute and chronic infection respectively, according dye test (DT) titres. ELISA IgG was positive in both groups, ELISA IgM was positive in 78.6 and 58.3% respectively, while ELISA IgA was positive in 85.7 and 33.3% of recent and chronic group respectively. In those sera with low IgG avidity (18.8%) we found specific IgM in 71.5 and 4.2% and IgA in 78.6 and 0.0% of recent and chronic groups respectively. Parallelling, 208 sera samples were classified according to the results of DT, indirect hemagglutination and complement fixation tests in the following groups: acute (97), intermediate (36), chronic (35) and negative (40). The results were: acute (96.9-64.9-55.6 and 65.9%); intermediate (97.2-63.8-44.4 and 47.2%); chronic (45.7-42.8-5.7 and 34.3%) for IgG, IgM, IgA and low IgG avidity respectively. The use of both acute markers, IgA and low IgG avidity in the diagnosis of toxoplasmosis is discussed. 相似文献
893.
894.
E. G. Harper R. P. Welch D. Contreras Lara J. S. Chang R. E. Calza 《Applied microbiology and biotechnology》1996,45(6):817-821
Three fungi Neocallimastix frontalis EB 188, Piromyces communis DC 193 and Orpinomyces ssp. RW 206, representing the predominant cultures isolated from cattle, were shown to respond to the addition of Aspergillus oryzae fermentation extract (i.e., Amaferm; BioZyme Inc., St. Joseph, Mo.) stimulation. Growth rates, protein and cellulase secretion
and fungal mass production were all accelerated in the presence of the extract. Analysis of volatile fatty acids produced
by these three species suggested that extract addition increased and altered gas production. Fractionation and preliminary
analysis of the components present in the soluble extract, which stimulated the growth of the cellulolytic fungus N. frontalis EB 188, were also attempted. Soluble and filtered, sterilized extract was treated prior to use as a stimulant. Pretreatments
included dialysis, ultraviolet irradiation, freeze thaw cycling, boiling, autoclaving, digestion with protease, autodigestion,
organic extraction, decolorizing-carbon binding and polyethylene glycol concentration. Boiling, protease treatment, organic
extraction, freeze thaw cycling and decolorizing-carbon binding reduced the ability of the extract to stimulate fungal cultures.
Gel electrophoresis methods demonstrated that protein- and cellulasesecretion profiles were not identical in control and stimulated
cultures. High-performance liquid chromatography methods allowed the separation of the extract into a limited number of ultraviolet-absorbing
peaks, of which several stimulated the physiology of the fungus.
Received: 6 December 1995/Received revision: 7 February 1996/Accepted: 4 March 1996 相似文献
895.
Tim Gruber Chenchen Pan Raian E. Contreras Tobias Wiedemann Donald A. Morgan Alicja A. Skowronski Sandrine Lefort Cahuê De Bernardis Murat Ophelia Le Thuc Beata Legutko Francisco J. Ruiz-Ojeda María de la Fuente-Fernández Angel Luis García-Villalón Daniel González-Hedström Melanie Huber Klara Szigeti-Buck Timo D. Müller Siegfried Ussar Cristina García-Cáceres 《Cell metabolism》2021,33(6):1155-1170.e10
896.
Summary The following describes a simple filter device for recovery of fermenter-grown algae. The process is based on the virtual reduction of the diameter of the filter pores, caused by shear stress of the fluid. Algae retention is accomplished in spite of the fact that the diameter of the filter pores is much larger than that of the single cell. 相似文献
897.
898.
899.
900.
This article details the geological and elemental character of the obsidian from the Soros Hill source on the Cycladic island of Antiparos, Greece. EDXRF was used to analyse 40 geological geo-referenced samples. The products are clearly chemically discriminated from those of the other Aegean sources, and those from the Carpathians and central Anatolia. While the obsidian is of excellent tool-making quality, the small size of its nodules seems to have made it a less attractive raw material, attested at only a handful of prehistoric sites in the central Cyclades. 相似文献