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The increasing occurrence of antibiotic-resistant bacteria combined with regulatory pressure and consumer demands for foods produced without antibiotics has caused the agricultural industry to restrict its practice of using antibiotic growth promoters (AGP) in food animals. The poultry industry is not immune to this trend, and has been actively seeking natural alternatives to AGP that will improve the health and growth performance of commercial poultry flocks. Bacillus probiotics have been gaining in popularity in recent years as an AGP alternative because of their health-promoting benefits and ability to survive the harsh manufacturing conditions of chicken feed production. This review provides an overview of several modes of action of some Bacillus direct-fed microbials as probiotics. Among the benefits of these direct-fed microbials are their production of naturally synthesized antimicrobial peptides, gut flora modulation to promote beneficial microbiota along the gastrointestinal tract, and various immunological and gut morphological alterations. The modes of action for increased performance are not well defined, and growth promotion is not equal across all Bacillus species or within strains. Appropriate screening and characterization of Bacillus isolates prior to commercialization are necessary to maximize poultry growth to meet the ultimate goal of eliminating AGP usage in animal husbandry. 相似文献
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Federico Cagnazzo Pierre-Henri Lefevre Daniel Mantilla Aymeric Rouchaud Riccardo Morganti Paolo Perrini Davide Di Carlo Cyril Dargazanli Gregory Gascou Carlos Riquelme Alain Bonafe Vincent Costalat 《Journal of neuroradiology. Journal de neuroradiologie》2019,46(1):9-14
Background and purpose
Placement of flow-diverters across the ostia of major ICA branches carries a risk of arterial occlusion. We determined the rate of occlusion of the supraclinoid ICA branches and the related symptoms, following coverage with flow-diverters.Materials and methods
A systematic search was performed in PubMed, MEDLINE, and EMBASE. We selected studies reporting treatments with flow-diverters in which the device was placed across the ostium of the OphtA, PcomA, or AchorA. Random-effects meta-analysis was used to pool the following outcomes: rate of arterial occlusion, diminished flow, incidence of related symptoms, factors associated with arterial occlusion.Result
Twenty-one studies evaluating 1152 supraclinoid ICA branches were included in the meta-analysis. The incidence of OphtA occlusion and associated symptoms was 5.9% (95 CI%?=?3.1–8.6%) (incidence rate?=?6% per patient-year), and 0.8% (95% CI?=?0.1–1.4%) (incidence rate?=?0.8% per patient-year), respectively. Although asymptomatic in all cases, PcomA showed a higher occlusion rate (20.7%, 95% CI?=?8.9–32.4%) (incidence rate?=?19.5% per patient-year). AchorA was occluded in 1% (95% CI?=?0.3–2.4%) of cases, with approximately 1% (95% CI?=?0.4–2.3%) of transient neurological symptoms (incidence rate?=?0.96% per patient-year). There was a trend toward higher odds of arterial patency among arteries arising from the aneurysm (OR?=?2.94, P?=?0.06). Demographic factors and multiple stents were not associated with higher risk of arterial impairment. Adequate collateral circulation was reported in 94.5% of patients with arterial occlusion.Conclusions
During aneurysm treatment, the ostium of the supraclinoid ICA branches can be covered with flow-diverter devices with low rates of neurological symptoms related to arterial occlusion. 相似文献40.