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Bruna de Cssia M. Ramos Danessa S. Boligon Gilson R. P. Moreira 《Ecological Entomology》2019,44(5):610-622
1. Larvae of tortoise beetles present exaggerated body parts in association with an abdominal shield, which is made of faeces and exuviae that are deposited on the urogomphi throughout ontogeny. Growth trajectories and scaling relationships of these functional structures associated with the shield, if any, are unknown. 2. This study of Gratiana spadicea first tested, under field conditions, whether there is adaptive value associated with the shield regarding protection against predation and sunlight. Then, under laboratory conditions, the growth trajectory and allometric relationships among body parts were investigated, including scoli, individual and apparent furcae, and shield. The influence of food deprivation on the development of these structures was also determined. 3. Findings from previous studies were confirmed, suggesting that the adaptive value assigned to the shield is related to protection against predators. The present study demonstrated for the first time that the shield acts as a parasol in cassidines, decreasing the exposure of their larval body to sunlight. The scoli and apparent furca are exaggerated structures of G. spadicea, the development of which involves allometric growth and greater energetic investment (positive allometry) during ontogeny. There was proportionally less energetic investment for somatic construction of individual furca (negative allometry) due to the accumulation of the exuviae. 4. The possible consequences, in terms of developmental costs and survivorship benefits associated with the evolution of such exaggerated structures, are discussed. 相似文献
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Enzyme immunoassay of oestrogen and progesterone receptors in uterine and intrauterine tissue during human pregnancy and labour 总被引:4,自引:0,他引:4
T Padayachi R J Pegoraro L Rom S M Joubert 《The Journal of steroid biochemistry and molecular biology》1990,37(4):509-511
Oestrogen and progesterone receptors were studied in the non-pregnant state, in early pregnancy and at term using monoclonal antibody enzyme immunoassays. Receptors for both steroids were found in tissues from non-pregnant patients and patients in early pregnancy. At term oestrogen receptors were undetectable in all tissues studied. Progesterone receptors were undetectable in chorion, amnion and placenta at term, while present in extremely low concentrations in decidua and myometrium. 相似文献
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Bruna Tedeschi Patrizia Vernole M.Lucia Sanna Benedetto Nicoletti 《Human genetics》1992,89(5):543-547
Summary Chromosome fragile sites are inducible by aphidicolin in cultured human lymphocytes. To assess the frequency and distribution of these common fragile sites in the general population, a cytogenetic survey was performed on 126 subjects, 59 males and 67 females, whose age ranged from 1 day to 72 years. Common fragile sites, induced by aphidicolin, were widespread and showed a remarkably different sensitivity among individuals; age influenced the overall frequency of fragile sites. Moreover, both age and sex seemed to modulate the expression of specific fragile sites. In our population, the most common fragile sites were: 3p14, 16q23, Xp22, 6q26, 1p31, 4q31, 1p22, 7q22, 2q33, 3q27, 2q31, 7q32, 14q24, 10q22, 5q31, 2q37, 6p21. 相似文献
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Transcriptional activation of jun and actin genes by estrogen during mitogenic stimulation of rat uterine cells. 总被引:4,自引:0,他引:4
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G. Cassinelli E. Cotta G. D'Amico C. Della Bruna A. Grein R. Mazzoleni M. L. Ricciardi R. Tintinelli 《Archives of microbiology》1970,70(3):197-210
Summary A new microorganism, isolated in our laboratories and identified as Streptomyces michiganensis var. amylolyticus var. nova is described.Thaimycins can be obtained by submerged fermentation of this microorganism on a suitable culture medium.Three new related compounds, thaimycins A, B and C have been obtained and characterized by their physical and chemical properties.Data on the antiprotozoal and anthelmintic activities in vitro as well as in vivo are reported. 相似文献
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Bruna Tadolini Diana Fiorentini Laura Landi Luciana Cabrini 《Free radical research》1989,5(4):245-252
To find experimental conditions to selectively study the propagation phase of lipoperoxidation we studied the lipoperoxidation, catalyzed by FeCl2, of liposomes in a buffering condition where Fe2+ autoxidation and oxygen active species generation does not occur. Liposomes from egg yolk phosphatidylcholine. prepared by vortex mixing, do not oxidize Fe2+: on the contrary they oxidize Fe2+ when prepared by ultrasonic irradiation. Dimyristoyl phosphatidylcholine liposomes prepared by ultrasonic irradiation do not oxidize Fe2+. During sonication polyunsaturated fatty acid residues autoxidize and lipid hydroperoxides (LOOH) are generated. Only when LOOH are present in the liposimes Fe2+ oxidizes and its rate of oxidation depends on the amount of LOOH in the assay. The reaction results in the generation of both LOOH and thiobarbituric acid reactive material (TBAR): it is inhibited by butylated hydroxytoluene and has a acidic pH optimum; it is not inhibited by catalase and OH' scavengers. The reaction studied. thus, appears to be the chain branching and propagation phase of lipoperoxidation. When we studied the dependence of Fe2+ oxidation, LOOH and TBAR generation on FeCl2 concentration, we observed that at high FeCl2 concentrations the termination phase of lipoperoxidation was prevalent. Thus. by selecting the appropriate FeCl2 concentration the proposed experimental system allows study of either the propagation or the termination phase of lipoperoxidation. 相似文献
10.
M-07e human leukemic factor-dependent cell line provides a rapid and sensitive bioassay for the human cytokines GM-CSF and IL-3 总被引:5,自引:0,他引:5
G C Avanzi M F Brizzi J Giannotti A Ciarletta Y C Yang L Pegoraro S C Clark 《Journal of cellular physiology》1990,145(3):458-464
We have isolated a subline of the M-07 human megakaryoblastic leukemia cell line, designated M-07e, that requires either interleukin-3 (IL-3) or granulocyte macrophage colony-stimulating factor (GM-CSF) for growth, even in the presence of fetal calf serum. This cell line will not grow long term in any other cytokine although it responds slightly to IL-2, IL-4, IL-6, IL-9, and interferon-gamma. We have used the M-07e subline to develop a quantitative bioassay for the measurement of levels of either GM-CSF or IL-3. This assay is as sensitive to either factor as the human bone marrow colony assay (CFU-GM) or the chronic myelogeneous leukemic (CML) blast cell proliferation assay for these factors and is much more convenient and reliable than either. With this assay, as little as 25-50 pg/ml of either IL-3 or GM-CSF can be detected, a level that should render the assay useful for analysis of these molecules in samples from patients undergoing colony-stimulating factor therapy and from conditioned media from natural sources of the factors. In these cases, neutralizing antisera to each cytokine are required to demonstrate the specificity of the assay. This assay, in combination with quantitative immunoassays, should greatly facilitate the analysis of the roles of IL-3 and GM-CSF in regulating hematopoiesis both in patients and in natural sources of the cytokines. 相似文献