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991.
Jeff A. Graves Alice Helyar Martin Biuw Mart Jüssi Ivar Jüssi Olle Karlsson 《Conservation Genetics》2009,10(1):59-68
The growing number of grey seals in the Baltic Sea has led to a dramatic increase in interactions between seals and fisheries.
The conflict has become such a problem that hunting was introduced in Finland in 1998 and the Swedish Environment Protection
Agency recommended a cull of grey seals starting in 2001. Culling has been implemented despite the lack of data on population
structure. Low levels of migration between regions would mean that intensive culling in specific geographic areas would have
disproportionate effects on local population structure and genetic diversity. We used eight microsatellite loci and a 489 bp
section of the mtDNA control region to examine the genetic variability and differentiation between three breeding sites in
the Baltic Sea and two in the UK. We found high levels of genetic variability in all sampled Baltic groups for both the microsatellites
and the control region. There were highly significant differences in microsatellite allele frequencies between all three Baltic
breeding sites and between the Baltic sites and the UK sites. However, there were no significant differences in mtDNA control
region haplotypes between the Baltic sites. This genetic substructure of the Baltic grey seal populations should be taken
into consideration when managing the seal population to prevent the hunting regime from having an adverse effect on genetic
diversity by setting hunting quotas separately for the different subpopulations.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
992.
993.
Background
One of the most debated issues in the cognitive neuroscience of language is whether distinct semantic domains are differentially represented in the brain. Clinical studies described several anomic dissociations with no clear neuroanatomical correlate. Neuroimaging studies have shown that memory retrieval is more demanding for proper than common nouns in that the former are purely arbitrary referential expressions. In this study a semantic relatedness paradigm was devised to investigate neural processing of proper and common nouns.Methodology/Principal Findings
780 words (arranged in pairs of Italian nouns/adjectives and the first/last names of well known persons) were presented. Half pairs were semantically related (“Woody Allen” or “social security”), while the others were not (“Sigmund Parodi” or “judicial cream”). All items were balanced for length, frequency, familiarity and semantic relatedness. Participants were to decide about the semantic relatedness of the two items in a pair. RTs and N400 data suggest that the task was more demanding for common nouns. The LORETA neural generators for the related-unrelated contrast (for proper names) included the left fusiform gyrus, right medial temporal gyrus, limbic and parahippocampal regions, inferior parietal and inferior frontal areas, which are thought to be involved in the conjoined processing a familiar face with the relevant episodic information. Person name was more emotional and sensory vivid than common noun semantic access.Conclusions/Significance
When memory retrieval is not required, proper name access (conspecifics knowledge) is not more demanding. The neural generators of N400 to unrelated items (unknown persons and things) did not differ as a function of lexical class, thus suggesting that proper and common nouns are not treated differently as belonging to different grammatical classes. 相似文献994.
995.
Érico C. Dianese Maria Esther N. de Fonseca Rob Goldbach Richard Kormelink Alice K. Inoue-Nagata Renato O. Resende Leonardo S. Boiteux 《Molecular breeding : new strategies in plant improvement》2010,25(1):133-142
The best levels of broad-spectrum Tospovirus resistance reported in tomatoes thus far are conferred by the Sw-5 locus. This locus contains at least five paralogues (denoted Sw-5a through Sw-5e), of which Sw-5b represents the actual resistance gene. Here we evaluated a panel of seven PCR primer pairs matching different sequences within
a genomic region spanning the Sw-5a and Sw-5b gene cluster. Primer efficiency evaluation was done employing tomato isolines with and without the Sw-5 locus. One primer pair produced a single and co-dominant polymorphism between susceptible and resistant isolines. Sequence
analysis of these amplicons indicated that they were specific for the Sw-5 locus and their differences were due to insertions/deletions. The polymorphic SCAR amplicon encompass a conserved sequence
of the promoter region of the functional Sw-5b gene, being located in the position −31 from its open reading frame. This primer pair was also evaluated in field assays
and with a collection of accessions known to be either susceptible or resistant to tospoviruses. An almost complete correlation
was found between resistance under greenhouse/field conditions and the presence of the marker. Therefore, this primer pair
is a very useful tool in marker-assisted selection systems in a large range of tomato accessions. 相似文献
996.
Lunardi M Claus MP Alfieri AA Fungaro MH Alfieri AF 《Genetics and molecular biology》2010,33(4):745-749
The use of PCR assays with degenerate primers has suggested the existence of numerous as yet uncharacterized bovine papillomaviruses (BPV). Despite the endemic nature of BPV infections, the identification of BPV types in Brazilian cattle is still only sporadic. However, in a recent analysis of a partial segment of the L1 gene, we observed notable diversity among the BPV types detected. The aim of this study was to determine the phylogenetic position of the previously identified wild strain BPV/BR-UEL2 detected in the state of Paraná in Brazil. Since previous analysis of the partial L1 sequence had shown that this strain was most closely related to BPV type 4, genus-specific primers were designed. Phylogenetic analysis using complete L1 ORF sequences revealed that BPV/BR-UEL2 was related to BPV types classified in the genus Xipapillomavirus and shared the highest L1 nucleotide sequence similarity with BPV type 4 (78%). This finding suggests that BPV/BR-UEL2 should be classified as a potential new type of BPV in the genus Xipapillomavirus. 相似文献
997.
998.
Revisions of two new species groups of the genus Agra Fabricius are presented with the following species described as new: pusilla group - Agra cruciariasp. n. (Brazil), Agra gracesp. n. (Ecuador,Perú), Agra maxsp. n. (Brazil), Agra minasianussp. n. (Brazil),Agra notpusillasp. n. (Brazil), Agra pseudopusillasp. n. (Brazil); piranha group - Agra cesp. n. (Perú), Agra risserisp. n. (Bolivia,Brazil), Agra maiasp. n. (Bolivia), Agra piranhasp. n. (Ecuador); Agra tiputinisp. n. (Ecuador). Species of these two groups have adults that are the smallest in the entire genus, although this does not indicate they are closely related based on other attributes. All species are Amazonian in distribution. 相似文献
999.
Rigden DJ Botzki A Nukui M Mewbourne RB Lamani E Braun S von Angerer E Bernhardt G Dove S Buschauer A Jedrzejas MJ 《Glycobiology》2006,16(8):757-765
The bacterial hyaluronan lyases (Hyals) that degrade hyaluronan, an important component of the extracellular matrix, are involved in microbial spread. Inhibitors of these enzymes are essential in investigation of the role of hyaluronan and Hyal in bacterial infections and constitute a new class of antibiotics against Hyal-producing bacteria. Recently, we identified 1,3-diacetylbenzimidazole-2-thione and related molecules as inhibitors of streptococcal Hyal. One of such compounds, 1-decyl-2-(4-sulfamoyloxyphenyl)-1-indol-6-yl sulfamate, was co-crystallized in a complex with Streptococcus pneumoniae Hyal and its structure elucidated. The resultant X-ray structure demonstrates that this inhibitor fits in the enzymatic active site via interactions resembling the binding mode of the natural hyaluronan substrate. X-ray structural analysis also indicates binding interactions with the catalytic residues and those of a catalytically essential hydrophobic patch. An IC50 value of 11 microM for Hyal from Streptococcus agalactiae (strain 4755) qualifies this phenylindole compound as one of the most potent Hyal inhibitors known to date. The structural data suggested a similar binding mode for N-(3-phenylpropionyl)-benzoxazole-2-thione. This new compound's inhibitory properties were confirmed resulting in discovery of yet another Hyal inhibitor (IC50 of 15 microM). These benzoxazole-2-thiones constitute a new class of inhibitors of bacterial Hyals and are well suited for further optimization of their selectivity, potency, and pharmacokinetic properties. 相似文献