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91.
In the framework of the revision of the genus Orobanche (including Phelipaea) in the Mediterranean area, the original material for 31 names of new taxa described from North Africa by Ball, Battandier, Forsskål, Maire (partly with Emberger and Jahandiez), Persoon, Poiret and Pomel has been analysed. Typification is discussed, and where necessary types are designated. Accepted names and synonyms of the recognized taxa are given. Three species are illustrated, and one new combination (O. inexspectata) is proposed. 相似文献
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93.
Robert W. Fulton 《Biologicals》2013,41(1):31-38
Bovine viral diarrhea viruses (BVDV) have significant impact on beef and dairy production worldwide. The infections are widespread in the cattle populations, and in many production systems, vaccinations are utilized. BVDV strains have the hallmark of adversely affecting the immune system's many components, both the innate and acquired systems. While BVDV do cause primary infections and disease, their role in the pathogenesis of other agents underscores the complexity of viral–bacterial synergy. A greater understanding of the role of the persistently infected (PI) animal resulting from susceptible females infected at a critical stage of pregnancy has permitted acknowledgment of a major source of infection to susceptible animals. Not only do we understand the role of the PI in transmitting infections and complicating other infections, but we now focus attempts to better diagnose and remove the PI animal. Vaccinations now address the need to have an immune population, especially the breeding females in the herd. Biosecurity, detection and removal of the PI, and effective vaccinations are tools for potential successful BVDV control. 相似文献
94.
Thomas Wilke Martin Haase Robert Hershler Hsiu-Ping Liu Bernhard Misof Winston Ponder 《Molecular phylogenetics and evolution》2013,66(3):715-736
Although phylogenetic studies are increasingly utilizing multi-locus datasets, a review of GenBank data for the Gastropoda indicates a strong bias towards a few short gene fragments (most commonly COI, LSU rRNA, and SSU rRNA). This is particularly the case for the Rissooidea, one of the largest and most taxonomically difficult gastropod superfamilies. Here we analyze fragments of these three genes from 90 species to determine whether they can well resolve higher relationships within this superfamily, whether structurally aligned sequence datasets increase phylogenetic signal, and whether the inclusion of highly variable regions introduces noise. We also used the resulting phylogenetic data in combination with morphological/anatomical evidence to re-evaluate the taxonomic status of ‘hydrobioid’ family-level groups.Our results indicate that all three of the alignment strategies that were used resulted in phylogenies having similar signal levels. However, there was a slight advantage to using structural alignment for inferring family-level relationships. Moreover, the set of ‘standard’ gastropod genes supported recognition of many previously recognized families and provides new insight into the systematics of several problematic groups. However, some family-group taxa were unresolved and the relationships among families were also poorly supported, suggesting a need for more extensive sampling and inclusion of additional genes. 相似文献
95.
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97.
Xenotransplantation,risk, regulation and surveillance: social and technological dimensions of change
Abstract This paper examines xenotransplantation as one specific technique associated with the ‘new genetics’. The development of this particular technique is set within the context of emergent regulatory practices that simultaneously confront the national and global dimensions of the technique whilst balancing collective and individual risks and benefits. The adoption of an incremental, and arguably ad hoc, regulatory approach within the UK is assessed in relation to demands for active widespread social participation in the framing and assessment of risks. It is argued that there needs to be a full examination of the risks associated with the technique across a range of time frames before it can be adopted as part of the repertoire of modemmedicine. Moreover, the fullest possible mapping of the risk domains to be regulated and managed requires the active involvement of a diverse range of publics. By adopting an extended time-frame approach, it is argued that the claims-making of developers can be set within a more socially grounded context. Such a context requires the inclusion of situated publics, something currently lacking within the UK's approach to regulation. 相似文献
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99.
During meal events, a child's food can be contaminated through contacts with objects and surfaces, and/or unwashed hands that have chemical residues, increasing ingestion exposure of contaminants for the child. This is not surprising, given that very young children eat more with the hands than adults, are active, and play with toys and objects while eating. In addition, children's unwashed hands and toys are commonly inserted into their mouths during meal events, increasing exposure. By observing children during their meal events, information can be gathered on the frequency and duration of contacts between objects, foods, and hands, and the sequence of events before the hands, foods, or objects are inserted into the mouth. This article describes the process of refining a videotaping and video-translation methodology to capture micro-level activity time series (MLATS), in order to better quantify total exposure for young children as a result of their behavior during meal events and cross-contamination of foods and hands. These MLATS can be seen as detailed activity patterns that provide useful data, along with transfer coefficients and environmental concentration to estimate exposures. 相似文献
100.
Oligoribonucleotides of a predetermined base sequence begin-ing with adenylyl-3′ 5′-adenosine at the 5′ end have been synthesized in yields varying between 13% and 42%. The synthesis was carried out using primer-independent polynucleotide phosphory-lase from E. coli in the presence of high concentrations of primer and of sodium chloride. 相似文献