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41.
1. The honeybee Apis mellifera is of huge worldwide economic importance in the pollination of crops for human consumption. In recent years, honeybee populations have declined under pressure from diseases and pests. Climate change is increasingly being viewed as an additional threat to honeybees and yet only limited research has been carried out in this area. 2. This paper reports the advance of the first cleansing flight (‘spring cleaning’) of the honeybee in Poznań, Poland, i.e. flights to excrete faeces, over a month in the period 1985–2009. The timing of this flight is advanced not only by higher late winter/spring temperatures but also by higher temperatures in the previous summer and autumn. 3. This earlier activity gives hope that the reported earlier flowering of many native and cultivated species will not cause a pollination synchrony crisis.  相似文献   
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Engineered zinc-finger nucleases (ZFNs) enable targeted genome modification. Here we describe context-dependent assembly (CoDA), a platform for engineering ZFNs using only standard cloning techniques or custom DNA synthesis. Using CoDA-generated ZFNs, we rapidly altered 20 genes in Danio rerio, Arabidopsis thaliana and Glycine max. The simplicity and efficacy of CoDA will enable broad adoption of ZFN technology and make possible large-scale projects focused on multigene pathways or genome-wide alterations.  相似文献   
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Abstract: Two European species of the Diomedeoididae, an extinct family of procellariiform (tube‐nose) birds, have hitherto been distinguished primarily by size of their limb bones. Here, we describe an Early Oligocene (Rupelian) procellariifom coracoid that in all probability represents the larger species, Diomedeoides lipsiensis, and compare it to the coracoids of smaller diomedeoidids and extant procellariiforms. Using multivariate (Principal Component Analysis) and univariate analyses, we demonstrate that nearly all measurements are heavily size dependent, which makes the proportions and some other shape characters of little use as phylogenetic markers. Among eight measurements, the coracoid corpus width shows the highest correlation (higher than corpus depth) with body mass, permitting a precise calculation of over twofold difference in body mass between D. lipsiensis and smaller species. Among 16 qualitative characters analysed, the majority proved too variable to be used as markers of interfamily relationships and only 2–3, the ventral intermuscular line, sternocoracoid articulation (divided vs. undivided), and, with reservations, epimarginal crest vary consistently between the families. By far the most variable is the acrocoracoid process that tends to be deeper (more elongate dorsoventrally) in larger petrels but not in the albatrosses. However, the detailed shapes of the acrocoracoid heads are highly genus specific and suggest a genus‐level diversity among the Diomedeoididae from the Oligocene of Europe. The common features of the diomedeoidid coracoids are best interpreted as plesiomorphies, which accounts for some similarities to the Oceanitinae (that are probably basal among the crown‐group procellariiforms). The evidence from the coracoid is consistent with a stem‐group position of the Diomedeoididae as previously proposed by others. We emphasize the need of a group‐specific character analysis, primarily of allometries and levels of character variation, prior to a phylogenetic reconstruction.  相似文献   
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Rapid progress in genome research creates a wealth of information on the functional annotation of mammalian genome sequences. However, as we accumulate large amounts of scientific information we are facing problems of how to integrate and relate the data produced by various genomic approaches. Here, we propose the novel concept of an organ atlas where diverse data from expression maps to histological findings to mutant phenotypes can be queried, compared and visualized in the context of a three-dimensional reconstruction of the organ. We will seek proof of concept for the organ atlas by elucidating genetic pathways involved in development and pathophysiology of the kidney. Such a kidney atlas may provide a paradigm for a new systems-biology approach in functional genome research aimed at understanding the genetic bases of organ development, physiology and disease.Key Words: EuReGene, kidney, genome, development, pathophysiology, genetics  相似文献   
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Background. Although the beneficial effects of primary percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction (STEMI) have been demonstrated in a number of trials, most studies were conducted in Western countries. Experience, logistics and patient characteristics may differ in other parts of the world. Methods. Consecutive patients treated with primary PCI in Cinere Hospital, Jakarta, Indonesia, between January 2008 and October 2008 were compared with those treated in the Isala Clinics, Zwolle, the Netherlands. Results. During the study period, a total of 596 patients were treated by primary PCI, 568 in Zwolle and 28 in Jakarta. Patients in Indonesia were younger (54 vs 63 years), more often had diabetes (36 vs. 12%) and high lipids and were more often smokers (68 vs. 31%). Time delay between symptom onset and admission was longer in Indonesia. Patients from Indonesia more often had signs of heart failure at admission. The time between admission and balloon inflation was longer in Indonesia. At angiography, patients from Indonesia more often had multivessel disease. There was no difference in the percentage of restoration of TIMI 3 flow by primary PCI between the two hospitals. Conclusion. Patients with STEMI in Indonesia have a higher risk profile compared with those in the Netherlands, according to prevalence of coronary risk factors, signs of heart failure, multivessel disease and patient delay. Time delay between admission and balloon inflation was much longer in Indonesia, because of both logistic and financial reasons. (Neth Heart J 2009;17:418–21.)  相似文献   
48.
Precise control over organelle shapes is essential for cellular organization and morphogenesis. During yeast meiosis, prospore membranes (PSMs) constitute bell-shaped organelles that enwrap the postmeiotic nuclei leading to the cellularization of the mother cell's cytoplasm and to spore formation. Here, we analysed how the PSMs acquire their curved bell-shaped structure. We discovered that two antagonizing forces ensure PSM shaping and proper closure during cytokinesis. The Ssp1p-containing coat at the leading edge of the PSM generates a pushing force, which is counteracted by a novel pathway, the spore membrane-bending pathway (SpoMBe). Using genetics, we found that Sma2p and Spo1p, a phospholipase, as well as several GPI-anchored proteins belong to the SpoMBe pathway. They exert a force all along the membrane, responsible for membrane bending during PSM biogenesis and for PSM closure during cytokinesis. We showed that the SpoMBe pathway involves asymmetric distribution of Sma2p and does not involve a GPI-protein-containing matrix. Rather, repulsive forces generated by asymmetrically distributed and dynamically moving GPI-proteins are suggested as the membrane-bending principle.  相似文献   
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Previous studies have shown that the 5'HS4 DNaseI hypersensitive site of the chicken beta-globin locus is endowed with classic insulator activities: (i) it blocks the interaction between promoter and enhancers when it is inserted between them (ii) it confers expression of integrated foreign genes independent of their position in the chromatin. The aim of this present work was to determine whether the 5'HS4 element was able to stimulate the expression level and/or to increase the expression frequency of a luc+ reporter gene controlled by the rabbit WAP gene promoter. Two constructs with 5'HS4 insulator (p5'HS4-WAPluc) or without (pWAPluc) were introduced in mouse fertilised oocytes. All transgenic lines containing the 5'HS4 element (six lines) expressed the transgene whereas only two out of eight lines harbouring the pWAP-luc construct expressed the transgene to a significant level. Moreover, the mean level of expression was seven times higher in p5'HS4WAP-luc lines than in pWAP-luc lines. Even all these benefits on transgene expression, the 5'HS4 element did not confer a copy-dependent expression, did not decrease the ectopic expression of the reporter gene and did not decrease the variability of expression. Thus, the 5'HS4 element does not have all the properties of a perfect insulator on a construct containing the luc+ reporter gene controlled by the rabbit WAP promoter.  相似文献   
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