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681.
682.
Effects of the Biocontrol Agent Aspergillus flavipes on the Soil Microflora and Soil Enzymes in the Rooting Zone of Pepper Plants Infected with Phytophthora capsici 总被引:1,自引:0,他引:1 下载免费PDF全文
Changyuan Liu Li Liu Shuyi Yu Chunhao Liang Tianshu Guan Muhammad Irfan Kuihua Zhao 《Journal of Phytopathology》2015,163(7-8):513-521
This study examined the effect of ASD strain (Aspergillus flavipes), isolated from continuous cropping soil for pepper and named by the sampling position, on soil microflora and soil enzymes in rooting zone soil of healthy and diseased (Phytophthora capsici) pepper plants. Results showed that the ASD strain could significantly reduce the number of bacteria and actinomycetes, with a significant increase in fungi in the rhizosphere soil of both healthy and diseased plants. With increasing colonization time of the ASD strain, the number of bacteria and actinomycetes decreased initially and then increased gradually, while the number of fungi was first increased significantly and later decreased slowly. The soil enzyme activities of urease, acid phosphatase, invertase and dehydrogenase were significantly increased by the ASD strain, while the activity of catalase was not significantly increased. As time from inoculation with the ASD strain increased, the activities of various enzymes were higher than controls. Maximum enzyme activities were found on the tenth day after ADS inoculation. The response of soil enzyme activities affected by the ASD strain was as follows: urease > dehydrogenase > invertase > acid phosphatase > catalase. These results suggest that the biocontrol of ASD strain could improve the micro ecology of rhizosphere soil. 相似文献
683.
A crucial prerequisite for plant growth and survival under high salinity is maintenance of Na+ and K+ balance. Accumulation of Na+ and K+ in high concentration in the cytosol reduces crop yield. To cope with such imbalance ionic conditions, plants use a number of transporters to maintain Na+ and K+ homoeostasis inside the cell and regulate plant growth and development. This cation and pH homoeostasis is regulated by monovalent cation/proton antiporters (CPA) that fall in two categories, the CPA1 family that includes Na+/H+ NHX antiporters, and the CPA2 family that includes Cation/H+ (CHX) and K+ efflux antiporters (KEA). In this review we highlighted the role of NHX-antiporters in regulation of Na+ and K+ balance. NHX proteins are required for accurate K+ compartmentation. They mediate K+ specific vacuolar sequestration, pH adjustment, turgor and osmotic regulation, and play a unique role in stomatal movement and cell expansion. 相似文献
684.
Carl van Walraven Irfan A. Dhalla Chaim Bell Edward Etchells Ian G. Stiell Kelly Zarnke Peter C. Austin Alan J. Forster 《CMAJ》2010,182(6):551-557
Background
Readmissions to hospital are common, costly and often preventable. An easy-to-use index to quantify the risk of readmission or death after discharge from hospital would help clinicians identify patients who might benefit from more intensive post-discharge care. We sought to derive and validate an index to predict the risk of death or unplanned readmission within 30 days after discharge from hospital to the community.Methods
In a prospective cohort study, 48 patient-level and admission-level variables were collected for 4812 medical and surgical patients who were discharged to the community from 11 hospitals in Ontario. We used a split-sample design to derive and validate an index to predict the risk of death or nonelective readmission within 30 days after discharge. This index was externally validated using administrative data in a random selection of 1 000 000 Ontarians discharged from hospital between 2004 and 2008.Results
Of the 4812 participating patients, 385 (8.0%) died or were readmitted on an unplanned basis within 30 days after discharge. Variables independently associated with this outcome (from which we derived the nmemonic “LACE”) included length of stay (“L”); acuity of the admission (“A”); comorbidity of the patient (measured with the Charlson comorbidity index score) (“C”); and emergency department use (measured as the number of visits in the six months before admission) (“E”). Scores using the LACE index ranged from 0 (2.0% expected risk of death or urgent readmission within 30 days) to 19 (43.7% expected risk). The LACE index was discriminative (C statistic 0.684) and very accurate (Hosmer–Lemeshow goodness-of-fit statistic 14.1, p = 0.59) at predicting outcome risk.Interpretation
The LACE index can be used to quantify risk of death or unplanned readmission within 30 days after discharge from hospital. This index can be used with both primary and administrative data. Further research is required to determine whether such quantification changes patient care or outcomes.Readmission to hospital and death are adverse patient outcomes that are serious, common and costly.1,2 Several studies suggest that focused care after discharge can improve post-discharge outcomes.3–7 Being able to accurately predict the risk of poor outcomes after hospital discharge would allow health care workers to focus post-discharge interventions on patients who are at highest risk of poor post-discharge outcomes. Further, policy-makers have expressed interest in either penalizing hospitals with relatively high rates of readmission or rewarding hospitals with relatively low expected rates.8 To implement this approach, a validated method of standardizing readmission rates is needed.9Two validated models for predicting risk of readmission after hospital discharge have been published.10,11 However, these models are impractical to clinicians. Both require area-level information (e.g., neighbourhood socio-economic status and community-specific rates of admission) that is not readily available. Getting this information requires access to detailed tables, thereby making the model impractical. Second, both models are so complex that risk estimates cannot be attained from them without the aid of special software. Although these models have been used by health-system planners in the United Kingdom, we are unaware of any clinicians who use them when preparing patients for hospital discharge.Our primary objective was to derive and validate a clinically useful index to quantify the risk of early death or unplanned readmission among patients discharged from hospital to the community. 相似文献685.
686.
Muhammad Qasim Yoshiharu Fujii Muhammad Zaheer Ahmed Irfan Aziz Kazuo N. Watanabe M. Ajmal Khan 《Plant biosystems》2013,147(6):767-774
AbstractMedicinal plants are rich sources of bioactive phytochemicals. Production of such chemicals usually increased under unfavorable conditions. This study investigated the phytotoxic potential of 105 medicinal plants distributed in arid/semiarid areas along Arabian Sea coast of Pakistan. Total polyphenols, flavonoids, tannins and composition of individual phenolic compounds were also determined in species which showed high phytotoxic potential. Sandwich method was used to determine the phytotoxicity of medicinal plants on the growth of lettuce seedlings. Radicle growth was inhibited more than the hypocotyl growth. In general, halophytes showed higher phytotoxic potential than non-halophytes. Capparis cartilaginea, Indigofera hochstetteri, Parkinsonia aculeata and Prosopis glandulosa showed highest degree of inhibition. Higher amount of total phenols (16.35–25.33?mg GAE g?1), flavonoids (3.32-6.41?mg QE g?1) and tannins (1.54–2.54?mg TAE g?1) were found in these species. Pyrocatechol, quercetin, gallic, hydroxybenzoic and ferulic acids were detected as major phytotoxins, of which, gallic acid, pyrocatechol and quercetin were most abundant. These phytochemicals could be used for the production of natural, safe, healthy and eco-friendly agro-chemicals. Furthermore, these plants can be grown without encroaching agricultural lands, and can convert vast areas of arid/saline lands into economically viable resources, which also helps to halt climate change and desertification. 相似文献
687.
688.
Irfan S. Kathiriya Kavitha S. Rao Giovanni Iacono W. Patrick Devine Andrew P. Blair Swetansu K. Hota Michael H. Lai Bayardo I. Garay Reuben Thomas Henry Z. Gong Lauren K. Wasson Piyush Goyal Tatyana Sukonnik Kevin M. Hu Gunes A. Akgun Laure D. Bernard Brynn N. Akerberg Fei Gu Benoit G. Bruneau 《Developmental cell》2021,56(3):292-309.e9
689.
Jyothi K. Rajashekar Jonathan Richard Jagadish Beloor Jérémie Prévost Sai Priya Anand Guillaume Beaudoin-Bussières Liang Shan Dietmar Herndler-Brandstetter Gabrielle Gendron-Lepage Halima Medjahed Catherine Bourassa Fleur Gaudette Irfan Ullah Kelly Symmes Andrew Peric Emily Lindemuth Frederic Bibollet-Ruche Jun Park Priti Kumar 《Cell host & microbe》2021,29(6):904-916.e6
690.
An explorative trip was made to southwesternTurkey in April 1995 in search of pear thrips,Taeniothrips inconsequens (Uzel)(Thysanoptera: Thripidae), and its naturalenemies. Forty-three females and 13 males of apreviously undescribed species of the genusCeranisus Walker (Hymenoptera:Eulophidae) were found, mainly in floweringArbutus andrachne L. Although theparasitoid was found in association withseveral thrips species, but especially T.inconsequens adults and larvae, its host orhosts were not determined. The parasitoid isdescribed and given the name Ceranisusantalyacus S. Triapitsyn. 相似文献