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21.
Globodera ellingtonae was detected in Oregon in 2008. In order to make decisions regarding the regulation of this nematode, knowledge of its biology is required. We determined the host status of a diversity of potato (Solanum tuberosum) varieties in soil-based experiments and identified hatching stimulants in in vitro hatching assays. ‘Russet Burbank,’ ‘Desiree,’ ‘Modac,’ ‘Norland,’ ‘Umatilla,’ and ‘Yukon Gold’ were good hosts (RF > 14) for G. ellingtonae. Potato varieties ‘Maris Piper,’ ‘Atlantic,’ and ‘Satina,’ all which contain the Ro1 gene that confers resistance to G. rostochiensis, were not hosts for G. ellingtonae. In in vitro hatching assays, G. ellingtonae hatched readily in the presence of diffusates from potato (PRD) and tomato (Solanum lycopersicum; TRD). Egg hatch occurred in an average of between 87% and 90% of exposed cysts, with an average of between 144 and 164 juveniles emerging per cyst, from PRD- and TRD-treated cysts, respectively. This nematode hatched rapidly in the presence of PRD and TRD, with at least 66% of total hatch occurring by day 3 of exposure. There was no dose-response of egg hatch to concentrations of PRD or TRD ranging from 1:5 to 1:100 diffusate to water. When G. ellingtonae was exposed to root diffusates from 21 different plants, hatch occurred in 0% to 70% of exposed cysts, with an average of between 0 to 27 juveniles emerging per cyst. When root diffusate-exposed cysts were subsequently transferred to PRD to test viability, root diffusates from arugula (Eruca sativa), sudangrass (Sorghum bicolor subsp. drummondii), and common vetch (Vicia sativa) continued to inhibit egg hatch compared with the other root diffusates or water in which hatch occurred readily (60 to 182 juveniles emerging per cyst). Previously known hatching stimulants of G. rostochiensis and G. pallida, sodium metavanadate, sodium orthovanadate, and sodium thiocyanate, stimulated some egg hatch. Although, Globodera ellingtonae hatched readily in PRD and TRD and reproduced on potato, the pathogenicity of this nematode on potato remains to be determined.  相似文献   
22.

Background  

The similarity property principle has been used extensively in drug discovery to identify small compounds that interact with specific drug targets. Here we show it can be applied to identify the interactions of small molecules within the NF-κB signalling pathway.  相似文献   
23.
The benefits of pets on individual wellbeing is well established. But can pets also have benefits for romantic relationships? Using mixed methods, three studies explored the link between pet ownership and romantic relationship quality. First, using a grounded theory approach, we qualitatively investigated participants’ personal beliefs of how their pets influence their romantic relationships by coding open-ended responses. Results suggested that pets are seen as having predominantly positive (86.5%) effects, followed by few neutral (8%) and negative (4.5%) effects (study 1). We next compared a community sample of pet owners’ reports of relationship quality with those of non-pet owners. Results suggested that pet ownership was associated with several relationship benefits (greater overall relationship quality, partner responsiveness, adjustment, and relational investment) compared with couples without pets (study 2). Finally, we examined one possible reason for why pets may benefit relationships: A pet might provide the opportunity to practice empathic abilities, which is a crucial ability in the maintenance of positive relationships. Results showed that the number of years an individual owned a pet was positively correlated with empathic concern, which in turn was linked to several relationship benefits (commitment, couple identity, and relationship maintenance behaviors; study 3). In sum, three studies provided initial evidence that there is indeed a positive association between two important relationships in peoples’ lives: their partners and their pets.  相似文献   
24.
Comparing the shapes of regression functions   总被引:1,自引:0,他引:1  
Heckman  NE; Zamar  RH 《Biometrika》2000,87(1):135-144
  相似文献   
25.
Four studies examined how mental abstraction affects how people perceive their relationships with other people, specifically, how these relationships may be categorized in social groups. We expected that individuals induced to think abstractly would report fewer more global social groups, compared to those induced to think concretely, who would report more specific groups. However, induced abstract mindset did not affect how people structured their social groups (Study 2–4), despite evidence that the mindset manipulation changed the level of abstraction in their thoughts (Study 3) and evidence that it changed how people structured groups for a control condition (household objects, Study 4). Together, these studies suggest that while the way people organize their relationships into groups is malleable; cognitive abstraction does not seem to affect how people categorize their relationships into social groups.  相似文献   
26.
27.

Background

Thick blood films are routinely used to diagnose Plasmodium falciparum malaria. Here, they were used to diagnose volunteers exposed to experimental malaria challenge.

Methods

The frequency with which blood films were positive at given parasite densities measured by PCR were analysed. The poisson distribution was used to calculate the theoretical likelihood of diagnosis. Further in vitro studies used serial dilutions to prepare thick films from malaria cultures at known parasitaemia.

Results

Even in expert hands, thick blood films were considerably less sensitive than might have been expected from the parasite numbers measured by quantitative PCR. In vitro work showed that thick films prepared from malaria cultures at known parasitaemia consistently underestimated parasite densities.

Conclusion

It appears large numbers of parasites are lost during staining. This limits their sensitivity, and leads to erroneous estimates of parasite density.  相似文献   
28.
The involucrin genes of the mouse (Mus musculus) and the rat (Rattus norvegicus) have been cloned and sequenced. The coding region of each gene contains, at site P, a segment of repeats homologous to that of other nonanthropoid mammals. In contrast to the repeats of species belonging to different mammalian orders, many individual repeats of the mouse and the rat can be matched. Both before and after the divergence of the two species, these repeats have been the site of systematic alterations in nucleotide sequence. One of the alterations is the correction of nucleotides of one repeat by those of another. Corrected nucleotides may be closely linked to flanking nucleotides that are uncorrected; the systematic correction process therefore appears to be due to gene conversion. There is a stretch of 18 reiterated CAGs in the segment of repeats of the Mus gene; most of these reiterations were introduced recently, supporting the idea that the gene was generated originally from poly CAG. An antiserum to a synthetic peptide encoded by the segment of repeats of the Mus gene reveals differentiation- specific expression of the gene in the epidermis.   相似文献   
29.

Background  

Microarrays used for gene expression studies yield large amounts of data. The processing of such data typically leads to lists of differentially-regulated genes. A common terminal data analysis step is to map pathways of potentially interrelated genes.  相似文献   
30.
Mercuric ions were the only metal ions which prevented autolysis of Neisseria gonorrhoeae, as measured both by stabilization of optical density and by prevention of release of [3H]diaminopimelic acid.  相似文献   
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