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571.
Journal of Plant Growth Regulation - Among the different olive cultivars, ‘Shengeh’ olive trees have a poor yield, due to the incomplete flower bud development and increment of...  相似文献   
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Inter-comparison of absorbed dose rates for non-human biota   总被引:5,自引:3,他引:2  
A number of approaches have been proposed to estimate the exposure of non-human biota to ionizing radiation. This paper reports an inter-comparison of the unweighted absorbed dose rates for the whole organism (compared as dose conversion coefficients, or DCCs) for both internal and external exposure, estimated by 11 of these approaches for selected organisms from the Reference Animals and Plants geometries as proposed by the International Commission on Radiological Protection. Inter-comparison results indicate that DCCs for internal exposure compare well between the different approaches, whereas variation is greater for external exposure DCCs. Where variation among internal DCCs is greatest, it is generally due to different daughter products being included in the DCC of the parent. In the case of external exposures, particularly to low-energy beta-emitters, variations are most likely to be due to different media densities being assumed. On a radionuclide-by-radionuclide basis, the different approaches tend to compare least favourably for (3)H, (14)C and the alpha-emitters. This is consistent with models with different source/target geometry assumptions showing maximum variability in output for the types of radiation having the lowest range across matter. The intercomparison demonstrated that all participating approaches to biota dose calculation are reasonably comparable, despite a range of different assumptions being made.  相似文献   
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Radiation and Environmental Biophysics - Evaluating the stray radiation around medical electron accelerators is a mandatory issue. Surveying the radiation leakage dose is important for patients,...  相似文献   
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Interventions against obesity, are mainly around changing calorie intake and energy expenditure. Recently, some studies focused on the influence of circadian time of food intake on metabolic status. Here, we compare the role of calorie restriction and time restricted feeding followed by high-fat diet started post weaning, First, 52 male Wistarrats (3 weeks old) were divided into two groups: the high-fat diet (HFD, n = 42) and the control group (CON1, n = 11). After 17 weeks, five rats were randomly selected from each group for sample preparation. In the second phase, the animals in HFD group were assigned into four groups (n = 9): (1) 30% calorie restriction (CR), (2) day intermittent fasting (DIF), (3) night intermittent fasting (NIF), (4) adlibitum food intake (AL), (5) remained animal from the first phase control (CON2). Seventeen weeks of HFD started post-weaning did not cause fatty liver but it caused a significant difference in the body and the adipose tissue weight (P0.05). The results showed that longtime HFD did not lead to liver steatosis while the incorrect time of food intake predisposes the animal to the upcoming liver disease. This data indicate a significant role of timing of food intake rather than nutrition composition itself.  相似文献   
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Background

Currently, sufficient data exist to support the use of lactobacilli as candidates for the development of new oral targeted vaccines. To this end, we have previously shown that Lactobacillus gasseri expressing the protective antigen (PA) component of anthrax toxin genetically fused to a dendritic cell (DC)-binding peptide (DCpep) induced efficacious humoral and T cell-mediated immune responses against Bacillus anthracis Sterne challenge.

Methodology/Principal Finding

In the present study, we investigated the effects of a dose dependent treatment of mice with L. gasseri expressing the PA-DCpep fusion protein on intestinal and systemic immune responses and confirmed its safety. Treatment of mice with different doses of L. gasseri expressing PA-DCpep stimulated colonic immune responses, resulting in the activation of innate immune cells, including dendritic cells, which induced robust Th1, Th17, CD4+Foxp3+ and CD8+Foxp3+ T cell immune responses. Notably, high doses of L. gasseri expressing PA-DCpep (1012 CFU) were not toxic to the mice. Treatment of mice with L. gasseri expressing PA-DCpep triggered phenotypic maturation and the release of proinflammatory cytokines by dendritic cells and macrophages. Moreover, treatment of mice with L. gasseri expressing PA-DCpep enhanced antibody immune responses, including IgA, IgG1, IgG2b, IgG2c and IgG3. L. gasseri expressing PA-DCpep also increased the gene expression of numerous pattern recognition receptors, including Toll-like receptors, C-type lectin receptors and NOD-like receptors.

Conclusion/Significance

These findings suggest that L. gasseri expressing PA-DCpep has substantial immunopotentiating properties, as it can induce humoral and T cell-mediated immune responses upon oral administration and may be used as a safe oral vaccine against anthrax challenge.  相似文献   
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Accurate knowledge of in vivo anterior cruciate ligament (ACL) forces is instrumental for understanding normal ACL function and improving surgical ACL reconstruction techniques. The objective of this study was to estimate the change in ACL forces under in vivo loading conditions using a noninvasive technique. A combination of magnetic resonance and dual fluoroscopic imaging system was used to determine ACL in vivo elongation during controlled weightbearing at discrete flexion angles, and a robotic testing system was utilized to determine the ACL force-elongation data in vitro. The in vivo ACL elongation data were mapped to the in vitro ACL force-elongation curve to estimate the change in in vivo ACL forces in response to full body weightbearing using a weighted mean statistical method. The data demonstrated that by assuming that there was no tension in the ACL under zero weightbearing, the changes in in vivo ACL force caused by full body weightbearing were 131.4 ± 16.8 N at 15 deg, 106.7 ± 11.2 N at 30 deg, and 34.6 ± 4.5 N at 45 deg of flexion. However, when the assumed tension in the ACL under zero weightbearing was over 20 N, the change in the estimated ACL force in response to the full body weightbearing approached an asymptotic value. With an assumed ACL tension of 40 N under zero weightbearing, the full body weight caused an ACL force increase in 202.7 ± 27.6 N at 15 deg, 184.9 ± 22.5 N at 30 deg, and 98.6 ± 11.7 N at 45 deg of flexion. The in vivo ACL forces were dependent on the flexion angle with higher force changes at low flexion angles. Under full body weightbearing, the ACL may experience less than 250 N. These data may provide a valuable insight into the biomechanical behavior of the ACL under in vivo loading conditions.  相似文献   
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Context: Mustard gas (e.g. sulfur mustard (SM)) has been used as a chemical agent in several battles and is still a potential worldwide menace. Besides local absorption, particularly in the skin, eyes and lungs, systemic spread of the agent also has detrimental effects on gonads, bone marrow and nervous system. Moreover, chronic exposure of SM to respiratory system causes death. Inducing oxidative stress, and disturbing DNA and tissue repair systems, inflammation and cell death signaling pathways have been introduced as molecular mechanisms of the injury.

Methods: In this systematic review, more than 1200 (2000–2014) articles focusing on gross or molecular pathological reports in the acute phase of the respiratory injury after SM exposure were reviewed, followed by two different layers of gross and molecular pathological data (clinic and laboratory) integrated together in a spatio-temporal order. Role of epithelial, neutrophil and macrophage cells and three signaling pathways of inflammation, oxidative stress and cell death are covered in details.

Results and conclusion: Our results propose a critical role of interleukin-17 producing cells in acute and chronic inflammatory responses.  相似文献   

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