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The cytotoxic and radiosensitizing effects of hyperthermia was shown on Ehrlich ascites tumor cells heated in vitro. The effect of hyperthermia resulted in the formation of local lesions in membranes of dying cells. 相似文献
94.
H Zitzer H H H?nck D B?chner D Richter H J Kreienkamp 《The Journal of biological chemistry》1999,274(46):32997-33001
By using the yeast two-hybrid system we identified a novel protein from the human brain interacting with the C terminus of somatostatin receptor subtype 2. This protein termed somatostatin receptor interacting protein is characterized by a novel domain structure, consisting of six N-terminal ankyrin repeats followed by SH3 and PDZ domains, several proline-rich regions, and a C-terminal sterile alpha motif. It consists of 2185 amino acid residues encoded by a 9-kilobase pair mRNA; several splice variants have been detected in human and rat cDNA libraries. Sequence comparison suggests that the novel multidomain protein, together with cortactin-binding protein, forms a family of cytoskeletal anchoring proteins. Fractionation of rat brain membranes indicated that somatostatin receptor interacting protein is enriched in the postsynaptic density fraction. The interaction of somatostatin receptor subtype 2 with its interacting protein was verified by overlay assays and coimmunoprecipitation experiments from transfected human embryonic kidney cells. Somatostatin receptor subtype 2 and the interacting protein display a striking overlap of their expression patterns in the rat brain. Interestingly, in the hippocampus the mRNA for somatostatin receptor interacting protein was not confined to the cell bodies but was also observed in the molecular layer, suggesting a dendritic localization of this mRNA. 相似文献
95.
96.
C K?nig Y L Yan J Postlethwait S Wendler J A Campos-Ortega 《Mechanisms of development》1999,86(1-2):17-28
We describe the characterization of the zebrafish homologue of the human gene DLG3. The zebrafish dlg3 gene encodes a membrane-associated guanylate kinase containing a single PDZ domain. This gene was cloned using a gene-trap construct inserted in the gene's first intron. The insertion co-segregates with a viable mutation called humpback (hmp), which leads to formation of ankylotic vertebrae in adult fishes. Insertion and mutation have both been mapped to chromosome 12, in a segment which is syntenic with region p12 to q12 of human chromosome 17. The hmp mutant phenotype, however, appears to be due to two point mutations in the guanylate kinase domain rather than to the transgene insertion itself. The results of this study are discussed in the light of the possible function of the guanylate kinase domain. 相似文献
97.
Giovanni Murtas 《Systems and synthetic biology》2010,4(2):85-93
One of the major properties of the semi-synthetic minimal cell, as a model for early living cells, is the ability to self-reproduce
itself, and the reproduction of the boundary layer or vesicle compartment is part of this process. A minimal bio-molecular
mechanism based on the activity of one single enzyme, the FAS-B (Fatty Acid Synthase) Type I enzyme from Brevibacterium ammoniagenes, is encapsulated in 1-palmitoyl-2oleoyl-sn-glycero-3-phosphatidylcholine (POPC) liposomes to control lipid synthesis. Consequently molecules of palmitic acid released
from the FAS catalysis, within the internal lumen, move toward the membrane compartment and become incorporated into the phospholipid
bilayer. As a result the vesicle membranes change in lipid composition and liposome growth can be monitored. Here we report
the first experiments showing vesicles growth by catalysis of one enzyme only that produces cell boundary from within. This
is the prototype of the simplest autopoietic minimal cell. 相似文献
98.
S S Savinskaia E A Tol?kaia M S Balaian 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1982,(5):34-37
Serum specimens collected from 1002 persons in Moscow were tested for the presence of antibodies to hepatitis A virus (anti-HAV antibodies) by solid-phase enzyme immunoassay. The prevalence of these antibodies increased progressively with age from 10% in children aged 5-9 years to over 90% in the age groups of 40-49 years and over, the 50% immunity level being established at the age of 18 years. 79% of infants under 1 year were found to be immune, which was obviously due to the placental transfer of antibodies from mother to child. In a considerable part of seropositive persons over 30 years high or medium antibody titers were detected. These age groups showed a stable proportion of the low, medium and high level of anti-HAV antibodies. The prevalence of such antibodies was not related to sex. The presence of an ample amount of anti-HAV antibodies was determined in all of 18 tested lots of commercial serum immunoglobulin obtained from 3 different manufacturers. 相似文献
99.
The authors demonstrate stereospecificity of the action of butaclamol enantiomers on substrate inhibition of hypothalamic tyrosine hydroxylase (TH) and regulation of the tyrosine hydroxylase response by the presynaptic membrane (presynaptic receptors) of rat hypothalamus synaptosomes under membrane activation with dopamine. The effect of (+)-butaclamol on the substrate inhibition of TH was noticeable at a concentration of 10(-8)M, reaching a maximum at 10(-5)M. (-)-Butaclamol administered at the same concentrations did not influence the substrate inhibition of the enzyme. (+)-Butaclamol added to the incubation medium containing hypothalamic synaptosomes concurrently with dopamine (10(-5)M) completely blocked the regulatory action of the latter on TH, with this action mediated via presynaptic receptors. (-)-Butaclamol (10(-5)M) antagonized the action of dopamine under the same conditions. The data obtained indicate high stereo-specificity of butaclamol enantiomers as regards their effect on presynaptic regulation of TH, suggesting that elimination of the substrate inhibition of hypothalamic TH is a stereoselective effect of neuroleptics and can be a prognostically important criterion in the appraisal of compounds with potential neuroleptic activity. 相似文献
100.