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排序方式: 共有524条查询结果,搜索用时 15 毫秒
1.
The role of Orius tantillus (Motschulsky) (Hemiptera: Anthocoridae) in the predation of H. armigera was studied on both sorghum (Sorghum bicolor L.) and pigeonpea (Cajanus cajan L.), the predominant intercrop of small farmers in Andhra Pradesh, India. Adult Orius tantillus was observed in cages where there were eggs and first-instar larvae of H. armigera on sorghum and pigeonpea. We found that O. tantillus had two diurnal peaks of activity, after sunrise and before sunset. O. tantillus was found preying on first-instar larvae and not on eggs. However, a later immunoassay of O. tantillus collected on sorghum during a peak period of H. armigera oviposition activity showed that predation of eggs did occur under certain conditions. The activity of O. tantillus on sorghum was significantly higher on the flowers than elsewhere but this was not the case on pigeonpea. Therefore O. tantillus was a significantly more efficient predator on sorghum than on pigeonpea. The results indicate that O. tantillus could be an important predator of early stages of an H. armigera infestation, particularly in sorghum. 相似文献
2.
Ingrid Holst Olsen Nanna Holt Seppo W. Langer Jane P. Hasselby Henning Gr?nb?k Jens Hillings? Masti Mahmoud Morten Ladekarl Lene H. Iversen Andreas Kj?r Birgitte H. Federspiel Ulrich Knigge 《PloS one》2015,10(2)
BackgroundAppendiceal goblet cell carcinoids (GCCs) exhibit neuroendocrine and adenocarcinoma features.ResultsMedian age for f/m was 59/58 years, respectively, and similar for localized and disseminated disease. At diagnosis 54 patients had localized appendiceal disease (f/m: 29/25). According to TNM 24% had Stage I, 70% had Stage II and 6% had Stage III. Twenty-nine patients had disseminated disease (f/m: 27/2). Chromogranin A, synaptophysin and p53 were positive in >90%. Serotonin was positive in 70%. Median Ki67 index was 32% (6-75%) and higher in Tang group C (50%) compared to group A (30%; p<0.0001), and group B (30%; p<0.004). All patients had surgery. Sixty-three (76%) had radical resections including all patients with localized disease. Median OS was 83 months. The 1-, 5- and 10-year survival rates were 90%, 58%, and 38%, respectively. For localized disease OS was 164 months and 1-, 5- and 10-year survival rates were 100%, 80%, and 55%, respectively. For disseminated disease OS was 19 months and 1-, 5- and 10-year survival rates were 73%, 18% and 6%, respectively. The 1-, 5- and 10 year-survival rates for f/m were 87%/96%, 49%/76% and 31%/57%, respectively (p = 0.02). According to the Tang classification group A, B, and C OS was 118, 83 and 20 months, respectively (p = 0.0002).ConclusionThe Tang classification was found to be a significant prognostic factor, while the Ki67 index was not. Localized GCCs occurred equally in males and females, while disseminated GCCs were mostly seen in females. Median age of patients with localized disease and disseminated disease was identical. Cox regression analysis found Stage IV, focally positive synaptophysin and non-radical surgery as strongest negative prognostic factors. 相似文献
3.
Anne-Marie Lundsgaard Jacob B. Holm Kim A. Sjøberg Kirstine N. Bojsen-Møller Lene S. Myrmel Even Fjære Benjamin A.H. Jensen Trine S. Nicolaisen Janne R. Hingst Sine L. Hansen Sophia Doll Philip E. Geyer Atul S. Deshmukh Jens J. Holst Lise Madsen Karsten Kristiansen Jørgen F.P. Wojtaszewski Erik A. Richter Bente Kiens 《Cell metabolism》2019,29(1):50-63.e4
4.
Alba Rey‐Iglesia Shyam Gopalakrishan Christian Care David E. Alquezar‐Planas Anne Ahlmann Nielsen Timo Rder Lene Bruhn Pedersen Christina Nsborg‐Nielsen Mikkel‐Holger S. Sinding Martin Fredensborg Rath Zhipeng Li Bent Petersen M. Thomas P. Gilbert Michael Bunce Tobias Mourier Anders Johannes Hansen 《Molecular ecology resources》2019,19(2):512-525
In recent years, the availability of reduced representation library (RRL) methods has catalysed an expansion of genome‐scale studies to characterize both model and non‐model organisms. Most of these methods rely on the use of restriction enzymes to obtain DNA sequences at a genome‐wide level. These approaches have been widely used to sequence thousands of markers across individuals for many organisms at a reasonable cost, revolutionizing the field of population genomics. However, there are still some limitations associated with these methods, in particular the high molecular weight DNA required as starting material, the reduced number of common loci among investigated samples, and the short length of the sequenced site‐associated DNA. Here, we present MobiSeq, a RRL protocol exploiting simple laboratory techniques, that generates genomic data based on PCR targeted enrichment of transposable elements and the sequencing of the associated flanking region. We validate its performance across 103 DNA extracts derived from three mammalian species: grey wolf (Canis lupus), red deer complex (Cervus sp.) and brown rat (Rattus norvegicus). MobiSeq enables the sequencing of hundreds of thousands loci across the genome and performs SNP discovery with relatively low rates of clonality. Given the ease and flexibility of MobiSeq protocol, the method has the potential to be implemented for marker discovery and population genomics across a wide range of organisms—enabling the exploration of diverse evolutionary and conservation questions. 相似文献
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6.
Rafal Zgadzaj Euan K. James Simon Kelly Yasuyuki Kawaharada Nadieh de Jonge Dorthe B. Jensen Lene H. Madsen Simona Radutoiu 《PLoS genetics》2015,11(6)
Legumes have an intrinsic capacity to accommodate both symbiotic and endophytic bacteria within root nodules. For the symbionts, a complex genetic mechanism that allows mutual recognition and plant infection has emerged from genetic studies under axenic conditions. In contrast, little is known about the mechanisms controlling the endophytic infection. Here we investigate the contribution of both the host and the symbiotic microbe to endophyte infection and development of mixed colonised nodules in Lotus japonicus. We found that infection threads initiated by Mesorhizobium loti, the natural symbiont of Lotus, can selectively guide endophytic bacteria towards nodule primordia, where competent strains multiply and colonise the nodule together with the nitrogen-fixing symbiotic partner. Further co-inoculation studies with the competent coloniser, Rhizobium mesosinicum strain KAW12, show that endophytic nodule infection depends on functional and efficient M. loti-driven Nod factor signalling. KAW12 exopolysaccharide (EPS) enabled endophyte nodule infection whilst compatible M. loti EPS restricted it. Analysis of plant mutants that control different stages of the symbiotic infection showed that both symbiont and endophyte accommodation within nodules is under host genetic control. This demonstrates that when legume plants are exposed to complex communities they selectively regulate access and accommodation of bacteria occupying this specialized environmental niche, the root nodule. 相似文献
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8.
Live L. Nesse Kristin Berg Lene K. Vestby 《Applied and environmental microbiology》2015,81(6):2226-2232
Polyamines are present in all living cells. In bacteria, polyamines are involved in a variety of functions, including biofilm formation, thus indicating that polyamines may have potential in the control of unwanted biofilm. In the present study, the effects of the polyamines norspermidine and spermidine on biofilms of 10 potentially pathogenic wild-type strains of Escherichia coli serotype O103:H2, Salmonella enterica subsp. enterica serovar Typhimurium, and S. enterica serovar Agona were investigated. We found that exogenously supplied norspermidine and spermidine did not mediate disassembly of preformed biofilm of any of the E. coli and S. enterica strains. However, the polyamines did affect biofilm production. Interestingly, the two species reacted differently to the polyamines. Both polyamines reduced the amount of biofilm formed by E. coli but tended to increase biofilm formation by S. enterica. Whether the effects observed were due to the polyamines specifically targeting biofilm formation, being toxic for the cells, or maybe a combination of the two, is not known. However, there were no indications that the effect was mediated through binding to exopolysaccharides, as earlier suggested for E. coli. Our results indicate that norspermidine and spermidine do not have potential as inhibitors of S. enterica biofilm. Furthermore, we found that the commercial polyamines used contributed to the higher pH of the test medium. Failure to acknowledge and control this important phenomenon may lead to misinterpretation of the results. 相似文献
9.
Lene Müller 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1930,2(10):277-288
Ohne Zusammenfassung 相似文献
10.
In spores of the Blastocladiales there is a strict temporal correlation between the breakdown of the matrix of the gamma body and the swelling of the gamma body with the duration of the spore's motility. The swelling of the gamma body upon decay is interpreted as being due to water uptake. The swollen gamma bodies fuse with the plasmalemma and expel their content. We suggest that the swelling of the gamma body and its subsequent fusion with the plasmalemma of the spore are the means by which the spores of the Blastocladiales maintain osmotic balance with the medium in which they swim. The decay of the gamma body during the motile period of the spore is a separate and distinct process, not related to the mobilization of the remaining gamma bodies during encystment and cell wall formation. 相似文献