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Summary In the present work we have investigated the possible interaction between Bleomycin (B) and UV light or hyperthermia (HT) in the induction of lethal events in diploid yeast populations in the stationary phase of growth. UV and B acting as single agents determine sigmoid survival curves. The combination of UV + B produces different degrees of sensitization depending on dose ranges. For [B] = 7.5 µg/ml combined with different UV fluences an exponential course is observed, suggesting overlapping lesion specificity of the involved repair pathways (excision and recombination). The hyperthermia plus Bleomycin treatment produces different degrees of inactivation depending on the sequences. Maximal inactivation effect was obtained for the sequence B + HT. In the case of HT + B ([B] > 7.5 µg/ml) the obtained sensitization is lower. 相似文献
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Determination of the spectrum of beta-thalassemia genes in Spain by use of dot-blot analysis of amplified beta-globin DNA. 总被引:3,自引:1,他引:2 下载免费PDF全文
S Amselem V Nunes M Vidaud X Estivill C Wong L d''''Auriol D Vidaud F Galibert M Baiget M Goossens 《American journal of human genetics》1988,43(1):95-100
We have delineated the molecular lesions causing beta-thalassemia in Spain, a country that has witnessed the passage of different Mediterranean populations over the centuries, in order to evaluate the extent of heterogeneity of these mutations and to make possible simplified prenatal diagnosis of the disorder in that country. The use of the polymerase chain-reaction (PCR) technique to preferentially amplify beta-globin DNA sequences that contain the most frequent beta-thalassemia mutations in Mediterraneans enabled us to rapidly analyze 58 beta-thalassemia alleles in a dot-blot format either by hybridization with allele-specific radiolabeled oligonucleotide probes or by direct sequence analysis of the amplification product. The Spanish population carries seven different beta-thalassemia mutations; the nonsense codon 39 is predominant (64%), whereas the IVS1 position 110 mutation, the most common cause of beta-thalassemia in the eastern part of the Mediterranean basin, is underrepresented (8.5%). The IVS1 mutation at position 6 accounts for 15% of the defects and leads to a more severe form of beta+-thalassemia than originally described in most of the patients we studied. In this study, we demonstrate further the usefulness of the dot-blot hybridization of PCR-amplified genomic DNA in both rapid population surveys and prenatal diagnosis of beta-thalassemia. 相似文献
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Oxygen consumption rates (QO2) of laboratory reared stage one zoeae of Pandalus borealis (Krøyer) at 1.5, 3, 4.5, 6, and 9°C were 1.5, 2.2, 2.6, 3.6 and 4.1μ O2 · mg?1 · h?1, respectively. These values of QO2 correspond to 0.26, 0.38, 0.44, 0.60, and 0.70 μl O2 · individual?1 · h?1. At 10.5 °C oxygen consumption rates decreased suggesting thermally induced respiratory stress.The equation log10QO2 = 0.55 log10T°C + 0.086 describes the relationship between QO2 (μl O2 · mg?1 · h?1) and sea-water temperature between 1.5 and 9°C. Corresponding values of QO2 for an individual (μl O2 · h?1) exhibited the relationship log10QO2 = 0.55 log10T°C ?0.686.The minimum daily metabolic caloric requirements for an individual zoea ranged from 0.04 at 3 °C to 0.07 calories per day at 8 °C. The number of calories ingested daily ranged from 0.4 to 0.5 at 3 to 8 °C. 相似文献
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Nunes V. Casals T. Gallano P. Giménez F. J. Kere J. Williamson R. Estivill X. 《Human genetics》1989,83(3):305-306
Summary We report a rare allele detected using pMP6d-9, a probe very closely linked to cystic fibrosis (CF), on digestion with MspI. This allele has been found in normal and CF chromosomes, and therefore cannot be related to the mutation causing the disease. 相似文献
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Fine mapping of the Autosomal Dominant Split Hand/Split Foot Locus on Chromosome 7, Band q21.3-q22.1 总被引:6,自引:3,他引:3 下载免费PDF全文
Stephen W. Scherer Parvoneh Poorkaj Todd Allen Julia Kim Dorrit Geshuri Mark Nunes Sylvia Soder Karen Stephens Roberta A. Pagon Michael A. Patton Mary Anne Berg Tim Donlon Horacio Rivera R. A. Pfeiffer Kenji Naritomi Helen Hughes Maurizio Genuardi Fiorella Gurrieri Giovanni Neri Everett Lovrein Ellen Magenis Lap-Chee Tsui James P. Evans 《American journal of human genetics》1994,55(1):12-20
Split hand/split foot (SHFD) is a human developmental defect characterized by missing digits, fusion of remaining digits, and a deep median cleft in the hands and feet. Cytogenetic studies of deletions and translocations associated with this disorder have indicated that an autosomal dominant split hand/split foot locus (gene SHFD1) maps to 7q21-q22. To characterize the SHFD1 locus, somatic cell hybrid lines were constructed from cytogenetically abnormal individuals with SHFD. Molecular analysis resulted in the localization of 93 DNA markers to one of 10 intervals surrounding the SHFD1 locus. The translocation breakpoints in four SHFD patients were encompassed by the smallest region of overlap among the SHFD-associated deletions. The order of DNA markers in the SHFD1 critical region has been defined as PON–D7S812–SHFD1–D7S811–ASNS. One DNA marker, D7S811, detected altered restriction enzyme fragments in three patients with translocations when examined by pulsed-field gel electro-phoresis (PFGE). These data map SHFD1, a gene that is crucial for human limb differentiation, to a small interval in the q21.3-q22.1 region of human chromosome 7. 相似文献
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Aristóteles Philippe Nunes Queiroz Maria Lúcia Góes Araújo Nigel E. Hussey Rosângela P. T. Lessa 《Journal of fish biology》2023,102(1):27-43
Understanding the ecological role of species with overlapping distributions is central to inform ecosystem management. Here we describe the diet, trophic level and habitat use of three sympatric stingrays, Hypanus guttatus, H. marianae and H. berthalutzae, through combined stomach content and stable isotope (δ13C and δ15N) analyses. Our integrated approach revealed that H. guttatus is a mesopredator that feeds on a diverse diet of benthic and epibenthic marine and estuarine organisms, principally bivalve molluscs, Alpheus shrimp and teleost fishes. Isotopic data supported movement of this species between marine and estuarine environments. H. berthalutzae is also a marine generalist feeder, but feeds primarily on teleost fishes and cephalopods, and consequently occupies a higher trophic level. In contrast, H. marianae is a mesopredator specialized on shrimps and polychaetas occurring only in the marine environment and occupying a low niche breadth. While niche overlap occurred, the three stingrays utilized the same prey resources at different rates and occupied distinct trophic niches, potentially limiting competition for resources and promoting coexistence. These combined data demonstrate that these three mesopredators perform different ecological roles in the ecosystems they occupy, limiting functional redundancy. 相似文献
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Varilla González Jean David Macedo Alves Flávio Bagnatori Sartori Ângela Lúcia de Oliveira Arruda Rosani do Carmo 《Journal of plant research》2023,136(4):453-481
Journal of Plant Research - The Pterocarpus clade includes 23 genera previously attributed to different Fabaceae tribes. The recent rearrangements of many genera in the clade do not recognize... 相似文献
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