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101.
102.
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
103.
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
104.
Summary
Aspergillus sp strains from decaying lemons were tested for extracellular pectinase production, testing differently pretreated lemon peel as the carbon source instead of pectin. It was found that the production of extracellular polygalacturonase was about the same and that of pectinesterase substantially higher when unwashed fresh lemon peel was used instead of pectin. The culture filtrate obtained showed a clarifying capacity similar to that of a commercial pectinase preparation, but the vitamin C of the juice was less affected by the treatment. 相似文献
105.
Carmen Cascales Dan G. Craciunescu Paloma Martín-Sanz María Cascales 《Biological trace element research》1986,11(1):65-73
Enzyme activities and protein content were determined in the cytosolic and mitochondrial fractions of liver homogenates obtained from Rh(III) complex-, thioacetamide- and thioacetamide + Rh(III) complex-treated rats. The Rh(III) complex administered to nonthioacetamide-treated rats produced no significant changes either in the enzymatic activities assayed or in the protein concentration. The Rh(III) complex administered to thioacetamide-treated rats produced significant restoration of the following altered values: cytosolic and mitochondrial aspartate aminotransferase, glutamate dehydrogenase, NADP-isocitrate dehydrogenase, and protein concentration. However, a further increase was produced in the activities of glucose-6-phosphate dehydrogenase and malic enzyme. These increases can be interpreted in terms of an enhancement of the NADPH-dependent detoxifying processes and of nucleic acid synthesis and repair. 相似文献
106.
Zbigniew Szot Małgorzata Rochalska Maria Wojewódzka Andrzej Chimiak Witold Przychodzen 《Radiation and environmental biophysics》1986,25(1):31-35
Summary Male mice SAS/4 were injected i.v. with239Pu citr(IV) 0.27 µCikg–1–9.99 kBqkg–1. After 1 h 30 µmol kg–1 of 3,4,3 LICAM(C), N, N, N, N-tetra-(2,3-dihydroxybenzoyl)-spermine or Na3CaDTPA as a reference compound was given intraperitoneally. After 4 days the animals were sacrified and the Pu content in livers, kidneys, femurs and carcasses was determined by the liquid scintillation method. It was found that, as compared with the control, 3,4,3 LICAM(C) removed 83% of the Pu activity deposited in the liver, 71% of that in the femur and 79% of the Pu in the whole body. The Pu content in the kidneys exceeded the control value by about 50%. Na3CaDTPA removed 96, 86, 40 and 72% of plutonium from the liver, kidneys, femurs and carcasses respectively.Tetra-DHB-spermine caused the excretion of 50, 57 and 39% of Pu from liver, bone and whole body respectively. The retention of Pu in the kidneys was increased to 400% of the control value. 相似文献
107.
Anna Hillbricht-Ilkowska 《Hydrobiologia》1983,104(1):297-305
The length of the lorica (LL) of Keratella cochlearis cochlearis and of K. cochlearis tecta and the length of posterior spine (PSL) of the latter morphotype were measured in the strongly eutrophic basin and also in the mesotrophic basin of Lake Biwa, Japan, from September to December, 1980. In the population from the mesotrophic basin, the individuals with longer PSL prevail and the tecta forms are extremely rare. The LL values of both morphotypes from one sample do not differ. In December the LL increased to 95 µm in both morphotypes from 80 µm observed in September, while the PSL values decreased abrubtly in both basins in the middle of this period. It is suggested that the observed increase of LL could be related to the thermic factor, i.e. a steady decrease of water temperature, and the changes of PSL are correlated with the increase of nannoplankton and detritus aggregates noted in November. In this month an increase in fecundity and in the total numbers of rotifers took place as well (Hillbricht-Ilkowska, in press). 相似文献
108.
The efficiency of aerobic incubation was compared with incubation under various oxygen and carbon dioxide conditions for the isolation and subcultivation of three strains of Mycoplasma hyorhinis from VERO-cell cultures and subcultivation of three laboratory strains. Under anaerobic conditions with a low oxidation-reduction potential (at or below -115 mV) as obtained in jars, with catalysts, containing mixtures of 5%-10% CO2 in H2, very poor or no growth of any of the six M. hyorhinis strains was observed. When traces of oxygen were present (that is, under conditions with higher oxidation-reduction potentials, e.g. when omitting the catalyst in the above gas mixtures or in 5% CO2 + 95% N2) isolation from cell cultures was successful in most tests, but subcultivation of these primary isolates was seldom possible under these semi-anaerobic conditions. However, in most cases these primary isolates could be subcultivated aerobically, although aerobic conditions were unsatisfactory for isolation in about half of the experiments. Isolation of M. hyorhinis was optimal in 5% O2 + 95% N2, under which condition the isolates could also always be subcultivated. Isolation failed occasionally when 5% O2 + 5% CO2 + 90% N2 was used, thus indicating that 5% CO2 was slightly inhibitory. 5% CO2 in air and 10% CO2 either in air, H2 or N2 were also inadequate for isolation from cell cultures. In contrast to the findings with these cell culture-adapted M. hyorhinis strains, the laboratory strains could be subcultivated easily under all conditions tested except those with an oxidation-reduction potential at or below -115 mV; 100% CO2 was inhibitory for all 6 strains. Our findings may partly explain why M. hyorhinis is often considered "non-cultivable" on artificial media once adapted to cell cultures. The findings emphasize the need to employ also a micro-aerophilic condition (5% O2 in 95% N2) in the examination of cell cultures for mycoplasma. 相似文献
109.
Selection of Wine Yeasts for Growth and Fermentation in the Presence of Ethanol and Sucrose 总被引:5,自引:3,他引:2 下载免费PDF全文
Tahía Benítez Lucas del Castillo Andrs Aguilera Jaime Conde E. Cerdolmedo 《Applied microbiology》1983,45(5):1429-1436
To optimize the conversion of carbohydrates to ethanol, strains of several Saccharomyces species were examined for the ability to grow and ferment in a range of sucrose and ethanol concentrations. A total of 632 wine yeasts, most of them isolated from wineries in Andalusia and Extremadura, southwestern Spain, were subjected to screening and selection. Growth and fermentative capacity in different ethanol and sucrose concentrations varied from one strain to another. There was no correlation between growth and fermentative capacity. The best 35 strains grew in 15% ethanol and fermented in 18% ethanol. Ethanol accumulated, although at a reduced rate, after the cells stopped growing. Most yeast strains were highly fermentative in 50% sucrose. Some of them effectively utilized the carbohydrates of the culture, yielding final ethanol concentrations of > 14%. Of the 35 selected strains, 16 were promising for genetic analysis and breeding because of their capacity to sporulate. These strains were homothallic, and their spores were viable. The meiotic products analyzed so far were also homothallic. 相似文献
110.