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991.
992.
C Misael Chinchilla B Olga Marta Guerrero R Roberto Marín 《Revista de biología tropical》1986,34(1):1-6
White mice previously infected with 10(2), 10(3) or 10(4) Eimeria falciformis oocysts on days 0, 5, 10 or 30 were inoculated per os with 10(1), 10(2), 10(3) or 10(4) Toxoplasma oocysts. While the results obtained for mice with higher Toxoplasma inocula were consistent, animals with 10(1) and 10(2) oocysts previous inoculation with Eimeria showed important differences related with those infected only with Toxoplasma. For example, survival time was higher in animals infected with both parasites, especially if inoculated with Eimeria 30 days before Toxoplasma infection. Furthermore the number of T. gondii cysts found in the animals previously infected with Eimeria was lower compared with mice inoculated with Toxoplasma only. Body weight of mice infected with Toxoplasma previous infection with Eimeria was almost normal in relation to those infected only with Toxoplasma, indicating a probable pathological effect due to the parasite, more evident in "non immunized" mice. 相似文献
993.
The activity of antidromically identified abducens nucleus motoneurons and inter-nuclear neurons has been recorded during saccadic eye movements in the alert cat. The activity of these neurons has been demonstrated to be the sum of a velocity component proportional to eye velocity plus a position component proportional to instantaneous eye position during the movement. Results are discussed in relation to proposed models about the generation of saccadic eye movements. 相似文献
994.
F Aragón-Ortiz 《Revista de biología tropical》1986,34(1):55-58
The venom of Lachesis muta is a rich source of a thrombin-like enzyme. Its coagulant proteinase was purified by DEAE -Sephadex A -50 followed by agmatine CH -Sepharose and gel filtration on Sephadex G-100. On polyacrylamide gel electrophoresis at pH 8.4 a single band was observed. Its molecular weight by gel filtration was 49,000. The coagulant and esterolytic activities toward human fibrinogen and Tame of the inudasa were 662 NIH units/mg of protein and 4.37 delta OD225/min x 10(-3)/micrograms/ml, respectively. These values represent 23 and 5.7 fold increase over the crude venom. The enzyme mudasa, was evaluated with serum from human patients at Hospital Nacional de Ni?os Dr. Carlos Sáenz Herrera and found to be a valuable reagent for the quantification of fibrinogen on heparinized plasma. 相似文献
995.
M C Hidalgo M García G Cardenete A Sanz M de la Higuera 《Revista Espanola de Fisiología》1986,42(2):191-198
After 36% of hepatic mass removal , rainbow trout recovered its initial liver weight in 20-30 days, i.e., with a regeneration rate clearly lower than in mammals. During early regeneration process hematocrit index and hemoglobin content were slightly decreased, but both parameters rapidly reached their normal values. The evolution of both glycaemia and hepatic glycogen content supported the idea of the existence of a late regeneration wave, which, in this case, could begin at about the 20th post-operative day. 相似文献
996.
A new application of the Giemsa stain to demonstrate endocrine cells in deplasticized sections of Epon embedded material is described. Its application to the pancreas of Rana temporaria is illustrated. The technique does not require postfixation with OsO4 and is easily performed in 30 min. It allows the easy identification of three types of endocrine cells (A, B, and D). A cells, preferentially located at the islet periphery, stain purple-blue. B cells, which occupy the interior of the islet, display a lilac color. D cells give a strong purple color; they are located both in the periphery of the islets and scattered among acinar cells. Positive identification of the cell types was made by immunocytochemistry and electron microscopy. 相似文献
997.
A rapid, simple and reliable combined method for G-banding mammalian and human chromosomes 总被引:4,自引:0,他引:4
A simple and reliable method for G-banding chromosomes from human and mammalian cells is described. This rapid method combines hot saline and trypsin treatments and yields high quality G-bands in both bone marrow and cultured cells. 相似文献
998.
L. Manzocchi C. Tonelli G. Gavazzi N. Di Fonzo C. Soave 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1986,72(6):778-781
Summary This paper reports that the opaque-6 (o6) mutation of maize, which causes seedling lethality and interferes in the endosperm with the synthesis of zeins and b-32 protein, is a proline requiring mutant functionally allelic to proline-1 (pro-1). Furthermore, immunological studies on the b-32 content of ten independently originated o6 and pro-1 alleles demonstrated that four alleles contain an apparently normal b-32 protein while the others are either devoid of it or contain trace amounts of cross-reacting proteins of lower molecular weight. 相似文献
999.
Intergeneric hybrids of Saccharomyces cerevisiae and Zygosaccharomyces fermentati obtained by protoplast fusion 总被引:1,自引:0,他引:1
To obtain strains that are able to efficiently produce ethanol from different carbohydrates, mainly cellulose hydrolysates, several species of the genus Candida and a Zygosaccharomyces fermentati strain were examined for their ability to utilize cellobiose and produce ethanol, as well as for their thermotolerance and the possibility of genetic manipulation. Candida obtusa and Zygosaccharomyces fermentati tolerated the maximal temperature for growth, possessed the highest cellobiase activity, and offered the possibility of genetic manipulation, although neither of them proved to be a good producer of ethanol. Intergeneric hybrids of Saccharomyces cerevisiae and Z. fermentati were obtained after protoplast fusion. They were selected as prototrophic strains, after isolation of auxotrophic mutants from Z. fermentati and fusion with an S. cerevisiae strain which was also auxotrophic. The hybrids, which appeared at a frequency of 2 X 10(-7), presented characteristics of both parents, such as resistance to certain drugs and the ability to grow with either cellobiose or lactic acid as the sole carbon source; they were very stable, even under nonselective conditions. These hybrids may have important industrial applications as good fermenting strains. 相似文献
1000.
Saxelin ML Nurmiaho-Lassila EL Meriläinen VT Forsén RI 《Applied and environmental microbiology》1986,52(4):771-777
"Viili," a fermented milk product, has a firm but viscous consistency. It is produced with traditional mesophilic mixed-strain starters, which have various stabilities in dairy practice. Thirteen morphologically different types of phages were found in 90 viili samples studied by electron microscopy. Ten of the phage types had isometric heads with long, noncontractile tails, two had elongated heads with long, noncontractile tails, and one had a unique, very long elongated head with a short tail. Further morphological differences were found in the tail size and in the presence or absence of a collar, a baseplate, and a tail fiber. To find hosts for the industrially significant phages, we examined the sensitivities of 500 bacterial isolates from starters of the viili. Seven of the phages attacked Streptococcus cremoris strains, three attacked S. lactis subsp. diacetylactis strains, and four attacked Leuconostoc cremoris strains. Some phages differed only in their host specificity. Hosts were not found for 4 of the 13 morphological types of phages. 相似文献