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V. Oberemok K. Laikova I. Golovkin L. Kryukov R. Kamenetsky-Goldstein 《Plant biology (Stuttgart, Germany)》2022,24(1):3-8
A plant’s associated biota plays an integral role in its metabolism, nutrient uptake, stress tolerance, pathogen resistance and other physiological processes. Although a virome is an integral part of the phytobiome, a major contradiction exists between the holobiont approach and the practical need to eradicate pathogens from agricultural crops. In this review, we discuss grapevine virus control, but the issue is also relevant for numerous other crops, including potato, cassava, citrus, cacao and other species. Grapevine diseases, especially viral infections, cause main crop losses. Methods have been developed to eliminate viruses and other microorganisms from plant material, but elimination of viruses from plant material does not guarantee protection from future reinfection. Elimination of viral particles in plant material could create genetic drift, leading in turn to an increase in the occurrence of pathogenic strains of viruses. A possible solution may be a combination of virus elimination and plant propagation in tissue culture with in vitro vaccination. In this context, possible strategies to control viral infections include application of plant resistance inducers, cross protection and vaccination using siRNA, dsRNA and viral replicons during plant ‘cleaning’ and in vitro propagation. The experience and knowledge accumulated in human immunization can help plant scientists to develop and employ new methods of protection, leading to more sustainable and healthier crop production. 相似文献
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Does Helicobacter pylori eradication affect symptoms in nonulcer dyspepsia: a 5-year follow-up study 总被引:1,自引:0,他引:1
The role of Helicobacter pylori infection in nonulcer dyspepsia remains controversial. To date studies exploring the effect of H. pylori eradication on symptoms have reported conflicting results. Randomised control trials employing validated outcome measures have also been difficult to interpret because of several important issues such as the large placebo response seen in patients with nonulcer dyspepsia and both the natural variability in symptoms and symptom severity with time. The association of symptom improvement with resolution of gastritis has meant that the length of follow up employed in most studies has been insufficient. We report the findings of a randomised placebo controlled trial (n = 100), using a validated symptom questionnaire and 5 year follow up to determine the effect of H. pylori eradication on symptoms in nonulcer dyspepsia. In all 64 that were reviewed at 5 years there was a significant difference between patients who were H. pylori negative and those who remained positive with regard to complete symptom resolution, consumption of relevant medications and peptic ulcer disease development, in favour of active treatment. There was a trend for gradual symptom improvement over time irrespective of H. pylori status, which may reflect the natural history of this condition. For those who remained symptomatic at 5 years, there was no difference in symptom severity based on H. pylori status. The findings of this study support the use of H. pylori eradication in symptomatic patients with nonulcer dyspepsia both to induce symptom resolution and to prevent disease progression. 相似文献
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目的:对比两种不同的四联疗法对幽门螺杆菌根除失败后的根除率,选择可以有效弥补传统三联疗法的幽门螺杆菌根除失败措施的四联疗法。方法:选择2010年8月到2012年8月期间在我院住院治疗的幽门螺杆菌根除失败后患者90例作为研究对象。随机分为实验组和对照组,实验组的患者采取序贯疗法,对照组的患者采取标准四联疗法。对比两组的根除率以及临床疗效。结果:实验组患者的根除率为86.7%,对照组患者根除率为51.0%;实验组患者的临床总有效率为95.6%,对照组的临床有效率为77.8%;实验组的不良反应的总发生率为4.4%,对照组不良反应总发生率为20.0%。两组比较差异明显,P均0.05,具有统计学意义。结论:序贯疗法对幽门螺杆菌根除失败后的根除率以及疗效高于标准四联疗法。 相似文献
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Xavier Calvet Sergio Lario María José Ramírez‐Lázaro Antònia Montserrat Mariela Quesada Lynsey Reeves Helen Masters David Suárez‐Lamas Marta Gallach Mireia Miquel Eva Martínez‐Bauer Isabel Sanfeliu Ferran Segura 《Helicobacter》2010,15(3):201-205
Background: Studies comparing new monoclonal fecal tests for evaluating cure of Helicobacter pylori infection after treatment are scarce. The objective was to compare the diagnostic accuracy of three monoclonal stool tests: two rapid in‐office tools –RAPID Hp StAR and ImmunoCard STAT! HpSA – and an EIA test – Amplified IDEIA Hp StAR. Materials and methods: Diagnostic reliability of the three tests was evaluated in 88 patients at least 8 weeks after H. pylori treatment. Readings of immunochromatographic tests were performed by two different observers. Sensitivity, specificity, positive and negative predictive values and 95% confidence intervals were calculated. Results: All tests presented similar performance for post‐eradication testing. Sensitivity for detecting persistent infection was 100% for both Amplified IDEIA and RAPID Hp StAR and 90% for ImmunoCard STAT! HpSA. Respective specificities were 94.9%, 92.3–93.6% and 94.9%. Negative predictive values were very high (100%, 100% and 98.7% respectively). But positive predictive values were lower, ranging from 62.5 to 71.4%. Conclusion: All monoclonal fecal tests in this series presented similar performance in the post‐treatment setting. A negative test after treatment adequately predicted cure of the infection. However, nearly a third of tests were false positive, showing a poor predictive yield for persistent infection. 相似文献
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BACKGROUND: Recently, studies in adults and subsequently in children have demonstrated a very high success rate for sequential therapy as a primary therapy when compared to traditional therapy regimens. METHODs: We report our experience with a sequential therapy regimen for the eradication of Helicobacter pylori in five infected children and a young adult, whose conventional therapy regimens had been unsuccessful. RESULTS: Five patients failed the sequential therapy. All of them experienced between two and four failures of traditional therapy prior to the sequential treatment protocol. The only patient who succeeded on the sequential therapy had just one previous failure. All of our patients who had failed sequential therapy achieved eradication of the bacteria with quadruple therapy. CONCLUSIONS: In view of our disappointing results, sequential therapy is unsuccessful as a therapy for children and young adults who have failed previous treatment regimens. At the present time, quadruple therapy is indicated for this group. Well-designed placebo-controlled trials are indicated to further characterize this group of patients. 相似文献