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431.
432.
Surface markers of a purified peritoneal eosinophil population from Mesocestoides corti-infected BALB/c male mice 总被引:2,自引:0,他引:2
P M Hogarth K M Cruise I F McKenzie G F Mitchell 《Journal of immunology (Baltimore, Md. : 1950)》1980,124(1):406-411
Eosinophils of approximately 95% purity were prepared from the peritoneal cavities of BALB/c male mice infected with larval cestode, Mesocestoides corti. The alloantigenic surface marker phenotype of this cell population was shown to be H-2+Ly4+Ly5+Lyt-1-,2-,3-Ly-6-,7-Ia-Thy-1-TL-. Two of four anti-Lyt-2 sera were positive when tested on purified eosinophils by using the Staphylococcus aureus protein A sheep erythrocyte rosetting method, but absorption studies indicated that this reaction was not due to anti-Lyt-2 antibodies. Eosinophils are therefore Lyt-2-, although some Lyt-2 sera contain additional eosinophil reactive antibodies. A proportion (20 to 40%) of the population of eosinophils was positive for the Fc receptor, but all were negative for the C3 receptor and for surface immunoglobulin. 相似文献
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434.
I Barrai R Barale C Scapoli P Ambrosino M Beretta C Sbrana R Micheletti N Loprieno 《Mutation research》1992,267(2):173-182
The statistical methods for the analysis of mutagenicity and carcinogenicity underwent considerable theoretical-practical development following the need for assessing the mutagenic and carcinogenic potential of substances. Antimutagenicity is investigated through the analysis of respondents in dose-response assays, when two different molecules are administered separately and as a mixture to a respondent system. When the number of respondent units is high, and doses are orthogonal, it is possible to apply simple models such as analysis of variance. This is not always possible or common, and alternative approaches have been developed, based on multiple regression and on tables of proportions. In this work, some of the most frequently used methods for the assessment of joint responses are reviewed, particularly those based on multiple regression, such as the method of Shaeffer et al. and the method of Hass et al. In order to illustrate these methods, joint responses of perylene and cyclopentapyrene, of N-acetylcysteine and dinitropyrene, and of N-acetylcysteine and extracts from diesel exhausts were analyzed. An antagonistic effect of perylene on the action of CPP was detected by the algorithm of Shaeffer et al. The effect is not multiplicative, i.e., it is not proportional to the product of doses. The antimutagenic effect of N-acetylcysteine on dinitropyrene is multiplicative, as detected by the method of Hass et al. The latter reveals that the inhibition by N-acetylcysteine on the mutagenic effect of extracts from diesel exhausts is also multiplicative. 相似文献
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We use a model of modern baboon socio-ecology to explore the behavioral ecology and biogeography of the extinct Plio-Pleistocene baboons (genera Parapapio, Gorgopithecus, Dinopithecus, and Papio). The model is based on the way climate affects the baboons’ time budgets, and focuses on intersite variability in behavior rather than on species-typical patterns of behavior, as most previous approaches have done. We use climate estimates for individual fossil sites based on matching modern habitats using faunal profiles and estimates of individual species’ body masses given in the literature. The model allows us to examine the minimum and maximum sizes of groups that individual species would have been able to support at particular localities, and hence the biogeography of a species on a continental scale. In doing so, the model allows us to examine which variables are most responsible for limiting a species’ ecological and biogeographic flexibility, and through this to explore a species’ capacity for coping with climate change. Feeding time is identified as the main constraint. In general, large-bodied species would have had more difficulty surviving in as wide a range of habitats as smaller-bodied species, and this may explain the limited geographical distribution of large-bodied baboons such as Gorgopithecus and Dinopithecus. 相似文献
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A. S. Radchenko V. E. Borilkevich A. V. Borodin A. I. Zorin A. V. Mirolyubov 《Human physiology》2002,28(1):65-74
Spectral, coherent, and phase analysis within the low-frequency range of ECG records of athletic runners revealed that oscillations of ECG intervals (PQ-, RT-, P–T-, TP, and PP-intervals) were observed during orthostasis. These data were compared with the results of athletic exercise tests performed after the ECG examination. It was shown that the most effective type of adaptive reaction in these tests corresponds to a phase advance of the PQ-interval oscillations relative to the RT-interval oscillations. In the low-frequency range, the phases of the PQ-, RT-, and (P–T)-interval oscillations were ahead of the TP-interval oscillations, whereas the spectral density of the TP interval oscillations was significantly higher than the spectral density of the oscillations of the PC-, RT-, and (P–T)-intervals measured at the same frequency. The least effective type of adaptive reaction was shown to correlate with the phase advance of the TP-interval oscillations relative to the PQ-, RT-, and (P–T)-interval oscillations within the low-frequency range as well as with the lack of low-frequency modulation of the autospectra of the cardiac intervals of interest. 相似文献
440.
Yu. I. Rusakov A. P. Kolychev V. N. Shipilov V. M. Bondareva 《Journal of Evolutionary Biochemistry and Physiology》2003,39(4):425-432
Cerebropleural ganglia from 4000 individuals of the mollusc Anodonta cygnea were submitted to procedures developed for isolation of vertebrate pancreatic insulins: homogenization and extraction, stage-like isoelectrical sedimentation, and ion-exchange chromatography. As a result of purification of the obtained preparation, using high-effective liquid chromatography, there were identified 7 protein peaks differing by time of retention on the reverse-phase sorbent in acetonitryl gradient and designated as insulin-related peptides (IRP), IRP1-IRP7. The material was characterized by the peptide ability to inhibit specific binding of 125I-insulin and of insulin-related factor-1 (125I-IGF-1) by plasma membranes of the rat liver and brain. The IC50 value of peptide concentration (nM) able to replace 50% of the labeled hormone bound with the receptor amounted in the insulin radioreceptor system for IRP1 to 330, for IRP3 to 130, for IRP4 to 17, for IRP5 to130, for IRP6 to 420 nM. Peptide IRP7 at a maximal concentration (104 ng/ml) replaced less than 50% of labeled hormone, whereas in IRP2 no inhibitory ability was detected under these experimental conditions. The IC50 value in the case of 125I-IGF-1 amounted for IRP1, IRP4, and IRP5 to17, for IRP2 to 50, for IRP3 to 83, for IRP6 to 133 nM. IRP7 at a concentration of 104 ng/ml replaced less than 50% of labeled hormone. The same high relative affinity of the peptide IRP4 (12% of activity of standard insulin and IGF-1) to both receptor types is revealed. The results of analysis in two types of hormonal test systems indicate the ability of the insulin-related peptides of the anodonta cerebropleural ganglion to interact with the vertebrate receptor of insulin and IGF-1. This gives grounds to suggest the presence of the metabolic and growth-stimulating properties in these peptides. For the first time, the IGF-1 activity is revealed in insulin-like molecules in invertebrates. Taking into account the chromatographically revealed differences of physicochemical characteristics of individual IRP as well as predominance of their IGF-1-binding properties, there is suggested another organization of the IRP receptor-binding domains in IPR of this mollusc species, as compared with mammalian insulins. 相似文献