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61.
In searching for differentially expressed genes in human uterine leiomyomas (ULs), suppression sub-tractive hybridization was used to construct an UL up-regulated library, which turned out to represent 88genes. After two rounds of screening by reverse Northern analysis, twenty genes were proved to be up-regulated, including seventeen known genes and three genes with unknown function. All these genes werefirstly associated with UL. Three genes with notable difference were selected for Northern confirmationOur results proved the authenticity of the twenty genes. One gene named Phospholipase A2 (PLA2) showedup-regulation in 4/6 of the patients and investigation of tissue distribution indicated that it had obviousexpression in prostate, testis, liver, heart and skeletal muscle. 相似文献
62.
LINDA M. McINNES IAN R. DADOUR MEREDITH E. STEWART WILLIAM G. F. DITCHAM PETER MAWSON PETER B. S. SPENCER 《Molecular ecology resources》2005,5(3):504-506
Microsatellite loci were isolated from Carnaby's black cockatoo (Calyptorhynchus latirostris: Aves), a highly valued, endangered, and endemic species of bird from Western Australia. This study describes three dinucleotide and one tetranucleotide microsatellite loci for which the primers produced clear and polymorphic amplification patterns with between two and nine alleles and moderate levels of variability. Two additional dinucleotide markers which were monomorphic in the Carnaby's cockatoo were able to amplify and were polymorphic in two other species of black cockatoo, greatly increasing the utility of these markers. 相似文献
63.
Body size but not colony size increases with altitude in the holarctic ant,Leptothorax acervorum 下载免费PDF全文
ABEL BERNADOU CHRISTINE RÖMERMANN NANA GRATIASHVILI JÜRGEN HEINZE 《Ecological Entomology》2016,41(6):733-736
1. Bergmann's rule states that organisms inhabiting colder environments show an increase in body size or mass in comparison to their conspecifics living in warmer climates. Although originally proposed for homoeothermic vertebrates, this rule was later extended to ectotherms. In social insects, only a few studies have tested this rule and the results were ambiguous. Here, ‘body size’ can be considered at two different levels (the size of the individual workers or the size of the colony). 2. In this study, data from 53 nests collected along altitudinal gradients in the Alps were used to test the hypotheses that the worker body size and colony size of the ant Leptothorax acervorum increase with increasing altitude and therefore follow Bergmann's rule. 3. The results show that the body size of workers but not the colony size increases with altitude. Whether this pattern is driven by starvation resistance or other mechanisms remains to be investigated. 相似文献
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65.
Douglas J. Navarick 《Behavioural processes》1985,11(3):269-277
Adult human subjects chose between schedules containing stimuli (indicator lights) that the subjects were instructed to consider pleasurable. The schedules differed in amount of reinforcement (period of illumination) or delay (interval between a choice response and light onset). Although subjects preferred large to small amounts of reinforcement, they were essentially indifferent between immediate and delayed reinforcement. In contrast, previous data on video game reinforcement demonstrated preferences for both immediate and large amounts of reinforcement. The instructed reinforcer was thus partially effective in controlling choice but was not equivalent to a reinforcer that presumably had intrinsic value. 相似文献
66.
T. Phanitchat C. Apiwathnasorn S. Sungvornyothin Y. Samung S. Dujardin J.‐P. Dujardin S. Sumruayphol 《Medical and veterinary entomology》2019,33(4):476-484
Wing geometry helps to identify mosquito species, even cryptic ones. On the other hand, temperature has a well‐known effect on insect metric properties. Can such effects blur the taxonomic signal embedded in the wing? Two strains of Aedes albopictus (laboratory and field strain) were examined under three different rearing temperatures (26, 30 and 33 °C) using landmark‐ and outline‐based morphometric approaches. The wings of each experimental line were compared with Aedes aegypti. Both approaches indicated similar associations between wing size and temperature. For the laboratory strain, the wing size significantly decreased as the temperature increased. For the field strain, the largest wings were observed at the intermediate temperature. The two morphometric approaches describing shape showed different sensibilities to temperature. For both strains and sexes, the landmark‐based approach disclosed significant wing shape changes with temperature changes. The outline‐based approach showed lesser effects, detecting significant changes only in laboratory females and in field males. Despite the size and shape changes induced by temperature, the two strains of Ae. albopictus were always distinguished from Ae. aegypti. The present study confirms the lability of size. However, it also suggests that, despite environmentally‐induced variation, the architecture of the wing still provides a strong taxonomic signal. 相似文献
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Eliane S. Meier Thomas C. Edwards Jr Felix Kienast Matthias Dobbertin Niklaus E. Zimmermann 《Journal of Biogeography》2011,38(2):371-382
Aim During recent and future climate change, shifts in large‐scale species ranges are expected due to the hypothesized major role of climatic factors in regulating species distributions. The stress‐gradient hypothesis suggests that biotic interactions may act as major constraints on species distributions under more favourable growing conditions, while climatic constraints may dominate under unfavourable conditions. We tested this hypothesis for one focal tree species having three major competitors using broad‐scale environmental data. We evaluated the variation of species co‐occurrence patterns in climate space and estimated the influence of these patterns on the distribution of the focal species for current and projected future climates. Location Europe. Methods We used ICP Forest Level 1 data as well as climatic, topographic and edaphic variables. First, correlations between the relative abundance of European beech (Fagus sylvatica) and three major competitor species (Picea abies, Pinus sylvestris and Quercus robur) were analysed in environmental space, and then projected to geographic space. Second, a sensitivity analysis was performed using generalized additive models (GAM) to evaluate where and how much the predicted F. sylvatica distribution varied under current and future climates if potential competitor species were included or excluded. We evaluated if these areas coincide with current species co‐occurrence patterns. Results Correlation analyses supported the stress‐gradient hypothesis: towards favourable growing conditions of F. sylvatica, its abundance was strongly linked to the abundance of its competitors, while this link weakened towards unfavourable growing conditions, with stronger correlations in the south and at low elevations than in the north and at high elevations. The sensitivity analysis showed a potential spatial segregation of species with changing climate and a pronounced shift of zones where co‐occurrence patterns may play a major role. Main conclusions Our results demonstrate the importance of species co‐occurrence patterns for calibrating improved species distribution models for use in projections of climate effects. The correlation approach is able to localize European areas where inclusion of biotic predictors is effective. The climate‐induced spatial segregation of the major tree species could have ecological and economic consequences. 相似文献
70.
Preparation of chloroplast DNA from pea plastids isolated in a medium of high ionic strength 总被引:8,自引:0,他引:8
A simple, rapid, and inexpensive method for the preparation and purification of chloroplast DNA (cpDNA) from pea has been developed. The crucial step is the isolation of chloroplasts in a medium of high ionic strength (I congruent equal to 1.40 M). CpDNA from pea prepared according to this method has successfully been used for restriction enzyme mapping, Southern transfers, and cloning. 相似文献