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21.
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
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23.
Isolation of yeast with killer activity and its breeding with an industrial baking strain by protoplast fusion 总被引:5,自引:0,他引:5
Adela Bortol Clara Nudel Elda Fraile Ramon de Torres Ana Giulietti J. F. T. Spencer Dorothy Spencer 《Applied microbiology and biotechnology》1986,24(5):414-416
Summary Wild strains of Saccharomyces cerevisiae were isolated from dairy products, bakery goods, fresh fruit and vegetables, and tested for killer activity. Four isolates out of 238 strains possessed killer activity. The best of these was converted to the petite form and hybridized with an industrial strain of Saccharomyces cerevisiae by protoplast fusion. Thirty-eight out of 104 isolates had killer activity, and some of these had good dough-raising activity as well. 相似文献
24.
Summary An isochromosome of 15(q12) was found in a mentally retarded patient with behaviour disorders which included hyperactivity, short attention span, aggression, and autistic behaviour. There were only minor physical anomalies; he did not have the Prader-Willi syndrome. 相似文献
25.
Stability of plasmids R1-19 and R100 in hyper-recombinant Escherichia coli strains and in Salmonella typhimurium strains. 总被引:2,自引:1,他引:1
Plasmids R1-19 and R100 dissociate in hyper-recominant Escherichia coli strains in a way that is similar to but slower than dissociation in Salmonella typhimurium. The results presented suggest that the molecular mechanism for plasmid dissociation in hyper-recombinant E. coli strains is different than that in S. typhimurium strains. 相似文献
26.
Luis Molina y Vedia Mónica Torruella Ricardo Attar Ernesto Podesta Juan A. Reig Mirtha M. Flawia Héctor N. Torres 《Biochemical and biophysical research communications》1983,113(3):778-783
A monoclonal antibody against soluble adenylate cyclase was obtained. The antibody inhibits cyclase activities from several lower eucaryotic organisms but not activities associated to testicular cytosol or turkey erythrocyte membranes. 相似文献
27.
Andrew M. Torres 《American journal of botany》1968,55(5):582-589
The karyotypes of the three diploid (n = 10) species of the subg. Diplothrix (Zinnia—Compositae) were compared to determine whether there were any demonstrable differences which could then be sought in their polyploid derivatives. Because many of the chromosomes in a set were too similar to distinguish confidently between them, a method of analysis was developed which measures the similarity of whole sets of chromosomes rather than individual ones. The method consists of measuring the distances between graph-plotted vertices representing arm lengths of chromosomes of real or paper hybrids and then comparing these distances by means of U tests with those similarly derived for the “parents.” This procedure obviates the need of attempting to identify morphologues (morphologically similar chromosomes) in a somatic diploid root-tip cell and to equate corresponding pairs of chromosomes from different cells of a single plant or from different species or hybrids. No demonstrable differences in the karyotypes of diploid cespitose zinnias were found. Analysis of previously published data by this method indicated that there has been a general non-objectivity and non-operationalism in the determination of homologous chromosomes, and a general but unwarranted assumption that morphologues are in reality genologues (genetically corresponding chromosomes). 相似文献
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29.
Micronekton and macrozooplankton in the open waters near Antarctic ice edge zones (AMERIEZ 1983 and 1986) 总被引:4,自引:4,他引:0
Summary Micronekton and macrozooplankton assemblages (0–1000 m) were sampled from the open ocean in the vicinity of marginal ice zones in the southern Scotia and western Weddell Seas using midwater trawls. Small regional differences in species composition were found in the differing hydrographic settings with the Scotia Sea being slightly more diverse. Most species exhibited broad vertical ranges with no distinct pattern of vertical movement. Exceptions were mesopelagic fish and Salpa thompsoni which undertook diel vertical migrations. Biomass was high (2.4–3.1 g DW/m2), comparable to Pacific subarctic waters. Euphausia superba and Salpa tompsoni were the numerical and biomass dominants, representing over 50% of the total numbers and standing stocks. In terms of biomass, euphausiids were the most important group at shallow depths (0–200 m) but were surpassed by salps in the Scotia Sea and mesopelagic fish in the Weddell Sea when all depths down to 1000 m were considered. Pelagic fish biomass (3.3–4.4 g WW/m2) greatly exceeded published estimates for birds (0.025–0.070 g WW/m2), seals (0.068–0.089 g WW/m2) and whales (0.167 to 0.399 g WW/m2), making mesopelagic fish the most prevalent krill predators in the Antarctic oceanic system. 相似文献
30.
Old rats (28 months), when compared with young adults (9 months), did not show differences in activities of superoxide dismutase (SOD) or selenium-dependent and -independent glutathione peroxidases (GPx), or in levels of GSH, GSSG, GSSG/GSH and endogenous peroxidation in liver and brain. Rates of stimulated peroxidation in vitro were decreased in the livers of old rats. Old animals showed decreased levels of hepatic catalase and glutathione reductase. Nevertheless, when enzyme activities were referred to cytochrome oxidase activity these decreases disappeared, and GPx and SOD (brain) were even increased in old rats. 相似文献