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991.
In the scolex ganglia of the cestode Pelichnibothrium speciosum uni - and multipolar neurons can be found. Their neuroplasm is rich in free ribosomes. The ergastoplasmas membranes are frequently arranged in compact finger print-like structures. The nerve cells processes form tight junctions which cannot be interpreted as synaptic contacts. 相似文献
992.
Abstract cDNA-RNA liquid hybridization analysis was used to compare the RNA sequence homology between two members of the Nudaurelia β virus family, Trichoplusia ni virus ( T.ni V) and Dasychira pudibunda virus ( D.p V). Heterologous hybridization experiments demonstrated that these viruses shared little sequence homology. Using oligo(dT) chromatography and oligo(dT)12–18 as a primer for cDNA synthesis it was shown that neither T.ni V nor D.p V RNA genomes possess a poly(A) tract at the 3' end. 相似文献
993.
In this study it is shown that the higher molecular weight previously reported for tiger shark carbonic anhydrase (carbonate hydro-lyase, EC 4.2.1.1) compared to other carbonic anhydrases is decreased to a normal value around 30 000 after disulfide reduction of the enzyme. This difference in molecular weight is at least partly due to the existence of disulfide-linked glutathione and cysteine residues. Approx. 3 mol glutathione and a similar amount of cysteine are shown to be bound per mol enzyme. The presence of these factors also has effects on the enzyme activity. 相似文献
994.
The histones from slime mold Physarum polycephalum and calf thymus were characterized in terms of some physico-chemical properties. The molecular weights of six principal histone fractions of Ph. polycephalum were found to be the following: P1--22 700, P3--15 700, P4a--15 000, P4b--14 300, P5--12 800 and P6--10 500. Electrophoretically homogenous histone fractions H1, H2b and H4 of calf thymus and histones P1, P3, P4b and P6 of slime mold were obtained by gel-filtration on Acrylex P-60. These findings suggest that fractions P1, P4a, P4b, P5 and P6 of slime mold Ph. polycephalum are homologus with respect to the histone fractions H1, H3, H2b, H2a and H4 of calf thymus. Only fraction P3 has no corresponding fraction in the calf thymus histones; a fraction corresponding to histone P3 of slime mold was absent. 相似文献
995.
996.
997.
Summary Enzymes in reactive astrocytes of the corebral cortex were examined at the ultrastructural level in an attempt to resolve some conflicting aspects of astrocytic activity. Correlations between morphological and enzyme changes after injury established that the apparent increase in oxidative enzyme activity was exclusively mitochondrial and not an artefactual reaction product resulting from anoxic cellular damage. Pronounced glucose-6-phosphatase activity within cisternae of an increased amount of the granular endoplasnie reticulum was related to increased glycogen. Further evidence from acid phosphatase activity indieated that astrocytes played a minimal role in phagocytosis. 相似文献
998.
999.
ACTH stimulation of adenyl cyclase in adrenal homogenates 总被引:6,自引:0,他引:6
1000.
The stimulation of the phosphorylation of ribosomal protein S6 by cycloheximide and puromycin 总被引:7,自引:0,他引:7
The administration of cycloheximide or puromycin to rats in amounts that all but completely inhibited hepatic protein synthesis caused an increase in the amount of radioactive phosphate incorporated into the liver ribosomal protein S6; there was also an increase in the prominence of the derivatives of S6 which contain increasing numbers of phosphorylated serine residues. 相似文献