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981.
982.
Hydrobiologia - We studied downstream migration behaviour of Atlantic salmon smolt at a hydropower station that offers four safe (weir, new incision gate on weir, downstream bypass and Archimedes...  相似文献   
983.

Background  

In the cerebellum of newborn S100B-EGFP mice, we had previously noted the presence of a large population of S100B-expressing cells, which we assumed to be immature Bergmann glial cells. In the present study, we have drawn on this observation to establish the precise spatio-temporal pattern of S100B gene expression in the embryonic cerebellum.  相似文献   
984.
985.
Many stimuli such as hormones and elicitors induce changes in intracellular calcium levels to integrate information and activate appropriate responses. The Ca2+ signals are perceived by various Ca2+ sensors, and calmodulin (CaM) is one of the best characterized in eukaryotes. Calmodulin‐like (CML) proteins extend the Ca2+ toolkit in plants; they share sequence similarity with the ubiquitous and highly conserved CaM but their roles at physiological and molecular levels are largely unknown. Knowledge of the contribution of Ca2+ decoding proteins to plant immunity is emerging, and we report here data on Arabidopsis thaliana CML9, whose expression is rapidly induced by phytopathogenic bacteria, flagellin and salicylic acid. Using a reverse genetic approach, we present evidence that CML9 is involved in plant defence by modulating responses to bacterial strains of Pseudomonas syringae. Compared to wild‐type plants, the later responses normally observed upon flagellin application are altered in knockout mutants and over‐expressing transgenic lines. Collectively, using PAMP treatment and P. syringae strains, we have established that CML9 participates in plant innate immunity.  相似文献   
986.
ADHD has become one of the most frequent cause of referrals for children’ behaviour disorders. ADHD is a prevalent psychiatric condition affecting 5% to 9% of school-age children with regards to DSM-IV R diagnostic criteria. In addition, according to the results of different epidemiological studies, patients with ADHD very often experience comorbid conditions in 50% to 90% of the cases. The most frequent comorbidities include externalised disorders, (oppositional defiant disorder, conduct disorders), learning disorders, internalised disorders (anxiety, depression) and tics (chronic motor tics, Tourette’s syndrome). Given their negative impact on the outcome of ADHD in terms of affective and social functioning, and of social and school adaptation, these comorbid conditions should be carefully and systematically searched, even without any actual complaint. Although management of comorbid psychiatric conditions is never simple nor straightforward, therapeutic option should be considered taking into consideration both management of ADHD and specificity of these comorbidities.  相似文献   
987.
The DNA assisted solid-phase proximity ligation assay (SP-PLA) provides a unique opportunity to specifically detect prion protein (PrP) aggregates by investigating the collocation of 3 or more copies of the specific protein. We have developed an SP-PLA that can detect PrP aggregates in brain homogenates from infected hamsters even after a 107-fold dilution. In contrast, brain homogenate from uninfected animals did not generate a detectable signal at 100-fold higher concentration. Using either of the 2 monoclonal anti-PrP antibodies, 3F4 and 6H4, we successfully detected low concentrations of aggregated PrP. The presented results provide a proof of concept that this method might be an interesting tool in the development of diagnostic approaches of prion diseases.  相似文献   
988.
Cowpea (Vigna unguiculata (L.) Walp.) is one of the most important legume crops planted worldwide, but despite decades of effort, cowpea transformation is still challenging due to inefficient Agrobacterium-mediated transfer DNA delivery, transgenic selection and in vitro shoot regeneration. Here, we report a highly efficient transformation system using embryonic axis explants isolated from imbibed mature seeds. We found that removal of the shoot apical meristem from the explants stimulated direct multiple shoot organogenesis from the cotyledonary node tissue. The application of a previously reported ternary transformation vector system provided efficient Agrobacterium-mediated gene delivery, while the utilization of spcN as selectable marker enabled more robust transgenic selection, plant recovery and transgenic plant generation without escapes and chimera formation. Transgenic cowpea plantlets developed exclusively from the cotyledonary nodes at frequencies of 4% to 37% across a wide range of cowpea genotypes. CRISPR/Cas-mediated gene editing was successfully demonstrated. The transformation principles established here could also be applied to other legumes to increase transformation efficiencies.  相似文献   
989.
990.
The effect of chronic caffeine treatment on three different binding sites in five brain areas of mice is characterized. The sites studied were the adenosine receptor, using [3H] diethylphenylxanthine, the benzodiazepine receptor, using [3H] diazepam and the adenosine uptake site, using [3H] nitrobenzylthioinosine. Significant increases were only observed in adenosine receptors with the greatest degree of change seen in the cerebellum and brain stem at both 16 and 23 days of caffeine treatment. The lack of significant effects of chronic caffeine on benzodiazepine receptors and adenosine uptake sites indicates that the caffeine effect is specific. The effect of chronic caffeine treatment on the ontogency of adenosine receptors was also studied with the result showing a significantly accelerated development of the receptor in the caffeine treated animals. The adult adenosine receptor levels were 20–30% higher than those observed in control animals. The observed alterations in adenosine receptor number which occur as a consequence of caffeine consumption may underlie some of the behavioral effects of this cortical stimulant as well as provide insights concerning the mechanisms of tolerance to and dependence on caffeine.  相似文献   
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