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91.
92.
A new species,Acanthocephaloides cyrusi, is described from the fishesSolea bleekeri andPomadasys commersoni from Lake St. Lucia, Natal, South Africa. It is distinguished from the other species in the genus by the more marked sexual dimorphism in length, the arrangement of hooks, the proboscis with the longest hooks at the anterior-most extremity and the greater size of the proboscis hooks and body spines. An acanthella, which may represent this species, was found in the tanaidApseudes digitalis. 相似文献
93.
Austin L. Shug Mary J. Schmidt Gregory T. Golden Ruggero G. Fariello 《Life sciences》1982,31(25):2869-2874
A differential distribution of carnitine was found in twelve microdissected areas of the frozen canine brain. The cerebellar cortex showed the highest level of carnitine, while the lowest amounts were found in the hippocampus and pons sections of the brain. However, the inability to demonstrate changes in carnitine levels after stimulation of the major afferent pathways in the caudate nucleus, and failure to demonstrate K+ stimulated release of carnitine in rat brain slices suggest that carnitine does not have a direct neurotransmitter role in the brain. 相似文献
94.
95.
Gustavo de Rezende Corrêa Karinne Cristinne da Silva Cunha Aline Araujo dos Santos Elizabeth Giestal de Araujo 《Neurochemical research》2010,35(9):1343-1352
It was already shown that ouabain treatment can stimulate PKC isoenzymes leading to the activation of intracellular pathways
involved in cell survival, growth and proliferation. We have previously demonstrated that ouabain or PMA treatment increases
retinal ganglion cell survival, an effect mediated by PKC activation. The aim of this work was to investigate the role of
EGF receptors in the ouabain effect and also to study which PKC isoform is activated by treatment with ouabain and PMA. Our
results show that 2.5 μM tyrphostin, 1.0 μM PP1, 4.0 μM U73122, 1.0 μM JNK inhibitor V and 2.0 μM rottlerin blocked the ouabain
effect indicating an involvement of receptors for EGF, Src, PLC, JNK and PKC δ respectively. The effect of PMA was only abolished
when cultures were treated with rottlerin or with the JNK inhibitor suggesting the involvement of PKC δ and JNK. These results
indicate that PKC δ could be a key regulator of retinal ganglion cell survival. 相似文献
96.
Steven Weaver Mary B. Comer Carolyn L. Jahn Clyde A. Hutchison Marshall Hall Edgell 《Cell》1981,24(2):403-411
A set of four clones containing the two adult β-globin genes of the “single” type mouse C57BL/10 (genotype Hbbs/Hbbs) were isolated from a library of cloned restriction fragments. The two genes, designated βs and βt, were physically mapped onto a 32 kb segment of the chromosome carried by the four clones. βs and βt form a stable heteroduplex 1850 bp long, indicating that they are intact and conserved at this level of resolution throughout their length, including their intervening sequences. The βs gene is allelic with the βdmaj gene of the BALB/ c mouse (genotype Hbbd/Hbbd). These two alleles, as well as their surrounding sequences, are highly conserved. In contrast, heteroduplexes of βt with its BALB/c allele, βdmin, revealed three extensive but localized rearrangements. One region of non-homology falls within the large intervening sequence, IVS2. To the 5′ side of the βt/βdmin gene position two unequal substitutions were observed; each results in the net insertion of about 1000 bp into the Hbbd chromosome. The β/βdmin gene position is bracketed by a 1450 bp inverted repeat. One of the 1000 bp substitutions maps within this inverted repeat. 相似文献
97.
98.
Mary Dainty Arnost Kleinzeller A. S. C. Lawrence Margaret Miall Joseph Needham Dorothy M. Needham Shih-Chang Shen 《The Journal of general physiology》1944,27(4):355-399
1. An investigation of the physicochemical properties of myosin has been carried out. Prepared under standard conditions, the ratio of flow-birefringence to protein concentration is uniform. The effect of electrolytes, pH, and urea on the flow-birefringence and viscosity (relative and anomalous) of myosin has been examined. 2. Decrease or abolition of flow-birefringence does not necessarily imply far reaching denaturation, since such effects can be reversed by a variety of means. 3. When a myosin solution is treated with adenosinetriphosphate, its flow-birefringence is decreased (average 48 per cent), its anomalous viscosity is retained, and its relative viscosity is decreased (average 14 per cent). The full effect of adenosinetriphosphate is obtained at 0.004 M; a molarity very much less than that of other substances which decrease the flow-birefringence of myosin. 4. The changes in the physicochemical properties of myosin brought about by adenosinetriphosphate are spontaneously reversible, and are connected with the enzymatic action of the protein as adenosinetriphosphatase. 5. Effects similar to those of adenosinetriphosphate on the physicochemical properties of purified myosin have been obtained so far only with inosinetriphosphate. 6. Inorganic phosphate is split off by myosin from inosinetriphosphate as well as from adenosinetriphosphate. Inorganic triphosphate is split by 1 to 2 per cent solution of three times precipitated myosin. 7. Adenosinediphosphate and inorganic triphosphate act as competitive inhibitors with adenosinetriphosphate, blocking the fall of flow-birefringence. 8. The implications of the results, and the conception of active enzymic groups attached to proteins participating in cell structure, whether contractile or non-contractile, are discussed in relation to present views on muscle physiology and other biological problems. 相似文献
99.
In order to evaluate the effectiveness and selectivity of various reagents in the solubilization of bacterial membranes, membranes of Micrococcus lysodeikticus were treated with detergents and chaotropic agents. The composition of the extracts so obtained was analyzed by rocket and two-dimensional immunoelectrophoretic techniques. Recovery of succinate-, malate-, and reduced nicotinamide adenine dinucleotide- (NADH) dehydrogenases, ATPase, succinylated lipomannan and cytochromes in the extracts was measured. Treatment with a variety of non-denaturing detergents produced extracts that were generally qualitatively uniform although quantitative differences were observed. The degree of extraction of various components was correlated with the hydrophile-lipophile balance. Several chaotropic agents were also evaluated as reagents for membrane solubilization. These agents were less effective in extraction of bulk protein, but produced extracts enriched in some membrane components. 相似文献
100.