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排序方式: 共有2637条查询结果,搜索用时 15 毫秒
1.
Sequential medical trials involving paired data 总被引:2,自引:0,他引:2
2.
Benjamin C. Blum Weiwei Lin Matthew L. Lawton Qian Liu Julian Kwan Isabella Turcinovic Ryan Hekman Pingzhao Hu Andrew Emili 《Molecular & cellular proteomics : MCP》2022,21(1):100189
Metabolism is recognized as an important driver of cancer progression and other complex diseases, but global metabolite profiling remains a challenge. Protein expression profiling is often a poor proxy since existing pathway enrichment models provide an incomplete mapping between the proteome and metabolism. To overcome these gaps, we introduce multiomic metabolic enrichment network analysis (MOMENTA), an integrative multiomic data analysis framework for more accurately deducing metabolic pathway changes from proteomics data alone in a gene set analysis context by leveraging protein interaction networks to extend annotated metabolic models. We apply MOMENTA to proteomic data from diverse cancer cell lines and human tumors to demonstrate its utility at revealing variation in metabolic pathway activity across cancer types, which we verify using independent metabolomics measurements. The novel metabolic networks we uncover in breast cancer and other tumors are linked to clinical outcomes, underscoring the pathophysiological relevance of the findings. 相似文献
3.
4.
E. Cortés A.A. Kirk J.A. Goolsby P.J. Moran A.E. Racelis M.A. Marcos-García 《Biocontrol Science and Technology》2011,21(11):1369-1373
Arundo donax L. (Poaceae) is native to Mediterranean Europe and invasive in the Rio Grande Basin of North America. Rhizomes from nine sites in France and Spain infested with a candidate control agent, the armoured scale Rhizaspidiotus donacis (Hemiptera: Diaspididae) weighed 50% less than those from nine sites without scale. 相似文献
5.
Plant-herbivore chemical signals and behavioral plasticity may enhance parasitoid host-foraging efficacy in the field; however, no studies have quantified the potential benefits from these factors under field-type conditions. The effect of plant-herbivore signals and learning on the foraging efficacy of Microplitis croceipes was quantified by directly observing and recording total and sequential duration of various foraging behaviors relative to 5 randomly placed herbivore-damaged and host-infested cotton plants and 20 undamaged and non-host-infested plants. Microplitis croceipes spent significantly more time searching (flying and antennation) on host infested versus uninfested plants. Antennation time was significantly and negatively correlated with successive host stings. Contrary to expectations of increased duration, flight time remained constant throughout the foraging bout, which may indicate that there was some learning associated with flight. These results suggest that plant-herbivore chemical signals and learning enhances the foraging efficacy of M. croceipes. 相似文献
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7.
《Fungal biology》2020,124(2):83-90
Latterly, the upsurge in use of antifungal drugs has brought about the emergence of several drug-resistance strains, making it skeptical to continue relying on current therapeutic regime. In the necessity of resistance-free antifungal agent, flavonoids presented possibilities of replacing existing drugs, displaying antifungal activity against pathogenic fungi. Among them, quercetin, one of the most representative flavonoids, exhibited antifungal activity against Candida albicans. To inspect the further understanding regarding quercetin, the antifungal mode of action of quercetin was investigated. In the initial step, the apoptosis was monitored after quercetin treatment. Moreover, intracellular levels of Mg2+ was assessed and was determined that Mg2+ increase occurred under the influence of quercetin. In addition, several features of mitochondrial dysfunction were monitored. Mitochondrial dysfunction triggers decrease in mitochondrial redox levels and leads to disruption in mitochondrial antioxidant system. Increased intracellular ROS and decreased intracellular redox levels were also displayed, indicating the occurrence of overall disruption in antioxidant systems. Sequentially, DNA fragmentation was observed and this DNA damage in turn induces apoptosis. In analyses, hexaamminecobalt(III) chloride (Cohex) was applied to inhibit Mg2+ transport between cytosol and mitochondria. Cohex attenuated the effects induced by quercetin, which demonstrates that the presence of Mg2+ is essential in quercetin-induced apoptosis. 相似文献
8.
Gerald Ozanne 《Aerobiologia》1990,6(1):8-10
Summary Under the ?Bois plus? scheme, the CTBA is currently developing a third party certification, based on the Scrivener law, with the aim of defending
the consumers' interests. At this early stage, wood preservatives and treated wood are checked for the efficacy of treatments
in order to ensure the stability and security of works in buildings and civil engineering. According to the different classes
of risks in service, ?Bois plus? provides the most adeguate level of protection. In the close future, the industry is planning to incorporate, with the help
of the CTBA and experts, health criteria within the frame of the ?Bois plus? certification scheme. The means could beSafety indexes, which are objectives of quality for professionals.Safety indexes are concentrations of substances in wood which can be taken as safe for humans and the general environment, while still toxic
for the wood pests.
This attractive experience aims to make with the brandname ?Bois plus? a synonym of efficacy and safety. This approach meets the essential requirements 1, 3, 4 of the 89/106 EEC directive: mechanical
resistance and stability/hygiene, health and environment/safety in use. 相似文献
9.
Berthold Lausen Torsten Hothorn Frank Bretz Martin Schumacher 《Biometrical journal. Biometrische Zeitschrift》2004,46(3):364-374
The identification and assessment of prognostic factors is one of the major tasks in clinical research. The assessment of one single prognostic factor can be done by recently established methods for using optimal cutpoints. Here, we suggest a method to consider an optimal selected prognostic factor from a set of prognostic factors of interest. This can be viewed as a variable selection method and is the underlying decision problem at each node of various tree building algorithms. We propose to use maximally selected statistics where the selection is defined over the set of prognostic factors and over all cutpoints in each prognostic factor. We demonstrate that it is feasible to compute the approximate null distribution. We illustrate the new variable selection test with data of the German Breast Cancer Study Group and of a small study on patients with diffuse large B‐cell lymphoma. Using the null distribution for a p‐value adjusted regression trees algorithm, we adjust for the number of variables analysed at each node as well. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
10.
A. Hamon J. C. Guillet J. J. Callec 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1990,167(3):363-376
1. The cerci of the cockroach Periplaneta americana bear longitudinal columns of wind-sensitive receptors which provide excitatory inputs to the giant interneurons (GIs) of the abdominal nerve cord. By using sound stimuli, we showed that spikes were more easily induced in the GIs from the most proximal than from the most distal receptors of the same column. 2. This was not due to a greater responsiveness of proximal sensilla to tones but to stronger synaptic connections; for the 3 largest GIs, the amplitude of the monosynaptic unitary EPSP tended to be all the higher as the stimulated sensillum was more proximal in each column. 3. The differences in EPSP size were due, at least partly, to presynaptic factors: a statistical analysis of the amplitude fluctuations of single-fibre EPSPs, showed that the amount of transmitter released per presynaptic impulse was larger for proximal than for distal sensory neurons in each column. 4. These differences in synaptic strength were correlated with differences in the structure of the afferent terminals. The location, the size and the shape of the axonal arbors are nearly the same for all sensory neurons of the same column, but proximal neurons arborize more profusely, and the terminal arbor of distal neurons is generally characterized by dorsal clusters of varicosities. 5. During postembryonic development, a decrease in the connection strength of 2 identified cercal neurons was accompanied by a retraction of ramifications on the medial side of their axonal arbor. 6. Possible mechanisms involved in the genesis and the remodelling of the gradient of synaptic strength are discussed in the light of available data and hypotheses relative to the development of ordered afferent connections. 相似文献