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Glycoconjugate Journal - Neisseria meningitidis is a major cause of bacterial meningitidis worldwide. Children less than five years and adolescents are particularly affected. Nearly all invasive...  相似文献   
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The International Journal of Life Cycle Assessment - A challenge that the road paving sector is facing concerns the achievement of highly performing bituminous asphalt mixture solutions that do not...  相似文献   
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The yield and quality of leafy vegetables can be compromised by reduced water availability. Glutamic acid is involved in different biological processes and among them it plays an important role in chlorophyll and proline biosynthesis. The aim of this work was to evaluate the possible efficacy of glutamic acid in counteracting water stress in romaine lettuce. Lettuce plants were grown in pots filled with substrate and subjected to water deprivation. A glutamic acid solution (1.9 mM) was applied as foliar treatment, both in stressed and non-stressed plants. The effect of the treatment was evaluated at different time points during the experiment in order to evaluate changes at a molecular, physiological, biochemical and agronomic level. Yield was reduced by 35% in stressed plants, while no significant changes in quality parameters were observed, except for nitrate content, which increased under water stress. At a molecular level, the expression of genes encoding for ROS scavenging enzymes was monitored but, apparently, glutamic acid did not significantly prevent the water stress response. Slightly positive effects deriving from glutamic acid application were found for nitrate and proline contents, suggesting that a possible mode of action of glutamic acid would involve a role for these molecules. Further studies are required, also on other crop species, for confirming these results. Different concentrations and application modes should be also tested.  相似文献   
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Protein oligomerization processes are widespread and of crucial importance to understand degenerative diseases and healthy regulatory pathways. One particular case is the homo-oligomerization of folded domains involving domain swapping, often found as a part of the protein homeostasis in the crowded cytosol, composed of a complex mixture of cosolutes. Here, we have investigated the effect of a plethora of cosolutes of very diverse nature on the kinetics of a protein dimerization by domain swapping. In the absence of cosolutes, our system exhibits slow interconversion rates, with the reaction reaching the equilibrium within the average protein homeostasis timescale (24–48 h). In the presence of crowders, though, the oligomerization reaction in the same time frame will, depending on the protein's initial oligomeric state, either reach a pure equilibrium state or get kinetically trapped into an apparent equilibrium. Specifically, when the reaction is initiated from a large excess of dimer, it becomes unsensitive to the effect of cosolutes and reaches the same equilibrium populations as in the absence of cosolute. Conversely, when the reaction starts from a large excess of monomer, the reaction during the homeostatic timescale occurs under kinetic control, and it is exquisitely sensitive to the presence and nature of the cosolute. In this scenario (the most habitual case in intracellular oligomerization processes), the effect of cosolutes on the intermediate conformation and diffusion-mediated encounters will dictate how the cellular milieu affects the domain-swapping reaction.  相似文献   
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The aim of this study is to provide preliminary observations on the microanatomy of Rhincodon typus skin using histology and electron microscopy analyses. Skin biopsies were obtained from a deceased juvenile male shark (548 cm total length) stranded in La Paz, Mexico, during February 2018. The results of this study evidenced the basic structure of the dermal denticles in the epidermis of the trunk of the shark, as well as the composition of the connective tissue in the hypodermis. Histological images of the hypodermis showed a high concentration of collagen fibres, formed by a large number of fine and wavy fibres of compact shape and little intercellular substance.  相似文献   
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Biological Invasions - It is widely assumed that spillover of alien parasites to native host species severely impacts naïve populations, ultimately conferring a competitive advantage to...  相似文献   
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Locally advanced rectal cancer requires a multidisciplinary management, traditionally based on neo-adjuvant (chemo) radiotherapy, conservative surgery with total mesorectal excision and adjuvant chemotherapy. Despite effective in term of local control, this strategy is linked to a high risk of distant metastasis (up to 30%). In this context, recent published randomized phase III clinical trials have tested the potential benefits with a different sequencing and/or intensification of the standard components of the trimodal therapy.Here, we briefly assess the efficacy and discuss the clinical relevance of total neoadjuvant treatment with a focus on indications and results in the short-course radiotherapy followed by chemotherapy use for this setting of patients. Long term results and additional prospective studies are necessary to more accurately estimate the clinical benefit and further establish the role of total neoadjuvant therapy in locally advanced rectal cancer disease.  相似文献   
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