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In many bird populations, individuals display one of several genetically inherited colour morphs. Colour polymorphism can be maintained by several mechanisms one of which being frequency-dependent selection with colour morphs signalling alternative mating strategies. One morph may be dominant and territorial, and another one adopt a sneaky behaviour to gain access to fertile females. We tested this hypothesis in the barn owl Tyto alba in which coloration varies from reddish-brown to white. This trait is heritable and neither sensitive to the environment in which individuals live nor to body condition. In Switzerland, reddish-brown males were observed to feed their brood at a higher rate and to produce more offspring than white males. This observation lead us to hypothesize that white males may equalise fitness by investing more effort in extra-pair copulations. This hypothesis predicts that lighter coloured males produce more extra-pair young, have larger testes and higher levels of circulating testosterone. However, our results are not consistent with these three predictions. First, paternity analyses of 54 broods with a total of 211 offspring revealed that only one young was not sired by the male that was feeding it. Second, testes size was not correlated with male plumage coloration suggesting that white males are not sexually more active. Finally, in nestlings at the time of feather growth testosterone level was not related to plumage coloration suggesting that this androgen is not required for the expression of this plumage trait. Our study therefore indicates that in the barn owl colour polymorphism plays no role in the probability of producing extra-pair young.  相似文献   
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Systemic necrotizing vasculitis comprises a group of diseases resembling polyarteritis nodosa and anti-neutrophil cytoplasmic antibody-associated vasculitis (ANCA): granulomatosis with polyangiitis, eosinophilic granulomatosis with polyangiitis, and microscopic polyangiitis. The definitive diagnosis is made in cooperation with a reference center for autoimmune diseases and rare systemic diseases or a competency center. The management goals are: to obtain remission and, in the long term, healing; to reduce the risk of relapses; to limit and reduce the sequelae linked to the disease; to limit the side effects and the sequelae linked to the treatments; to improve or at least maintain the best possible quality of life; and to maintain socio-professional integration and/or allow a rapid return to school and/or professional activity. Information and therapeutic education of the patients and those around them are an integral part of the care. All health professionals and patients should be informed of the existence of patient associations. The treatment of vasculitis is based on variable combinations of glucocorticoids and immunosuppressants, chosen and adapted according to the disease concerned, the severity and/or extent of the disease, and the underlying factors (age, kidney function, etc.). Follow-up clinical and paraclinical examinations must be carried out regularly to clarify the progression of the disease, detect and manage treatment failures and possible relapses early on, and limit sequelae and complications (early then late) related to the disease or treatment. A distinction is made between the induction therapy, lasting approximately 3–6 months and aimed at putting the disease into remission, and the maintenance treatment, lasting 12–48 months, or even longer. The role of the increase or testing positive again for ANCA as a predictor of a relapse, which has long been controversial, now seems to have greater consensus: Anti-myeloperoxidase ANCAs are less often associated with a relapse of vasculitis than anti-PR3 ANCA.

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Lecythis pisonis Cambess, popularly known as sapucaia, has great economic and socio-environmental potential. The objective of this study was to evaluate the establishment and in vitro morphogenesis of L. pisonis under the effect of disinfecting agents, plant growth regulators, and thermal stress. The study was divided into three experiments: (i) development of the disinfection protocol by testing different concentrations and times of exposure to sodium hypochlorite (NaOCl) and different concentrations and methods of amoxicillin application, (ii) in vitro budding induction by testing different concentrations of 6-benzylaminopurine (BAP) or kinetin (KIN) supplemented to Woody Plant Medium (WPM) and Murashige and Skoog (MS) culture media, and (iii) in vitro formation from plantlets by analyzing different concentrations of indole-3-butyric acid (IBA) with different exposure times to a thermal stress of 40°C. The disinfection of stem segments was effective using 3% NaOCl and 3.0 g L−1 amoxicillin solution. MS culture medium supplemented with 0.25 mg L−1 BAP induced more shoots in vitro. One milligram per liter IBA promoted greater rooting in vitro, and it is not necessary for thermal stress tolerance.

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107.
The hermaphroditic marine snail species Haminella solitaria was formerly included in the genus Haminoea, but it was recently assigned to the genus Haminella. The copulatory apparatus in H. solitaria was investigated by light and transmission electron microscopy to obtain additional information about this apparatus in cephalaspidean gastropods and to evaluate the taxonomic relevance of its morphofunctional features in the framework of a new phylogenetic tree of the family Haminoeidae. The copulatory apparatus in H. solitaria consisted of the atrium with a muscular wall and papilla, a seminal duct, and a single‐lobed prostate. Epithelial and subepithelial secretory cells were detected in the proximal and middle region of the atrium wall, and a third type of secretory cell occurred in the distal region of the muscular papilla. The seminal duct was lined by ciliated cells and its muscular wall included some vacuolar cells. The prostate in H. solitaria consisted of lateral pouches surrounding a large central lumen that was filled with spermatozoa. A single type of secretory cell intermingled with ciliated cells formed the epithelium of the prostate. A histological comparison between the copulatory apparatus in H. solitaria and Haminoea navicula revealed substantial differences that support the placement of these two species in different genera, as established by recent molecular studies.  相似文献   
108.
Current Fungal Infection Reports - This review has incorporated the knowledge and experience of the leads of each of the laboratory working parties of the fungal PCR initiative in order to provide...  相似文献   
109.
Calonectria leaf spot, caused by Calonectria pteridis, is a serious problem in Eucalyptus crops in both nursery and the field. Under ideal conditions, the disease can cause severe defoliation. It is known that calcium and potassium are directly related to the plant's resistance to pathogens. Thus, the knowledge of how a balanced fertilization of Ca and K interferes in the distribution of these nutrients at the infection site would contribute to elucidate the resistance of the plant related to its nutrition. This study investigated the effect of calcium and potassium fertilizer application on the content and distribution of these nutrients in the symptomatic leaf area, transition zone and asymptomatic leaf area over time. Eucalyptus seedlings were grown in nutrient solution under different Ca and K treatments (6 mmol/L K + 4 mmol/L Ca, 6 mmol/L K + 8 mmol/L Ca and 9 mmol/L K + 12 mmol/L Ca) and inoculated with C. pteridis. Leaves were removed at 24, 48 and 72 hr after inoculation (hai) and evaluated by X-ray microanalysis. The highest calcium content among the different leaf areas was observed in the symptomatic area, and the levels in this area increased over time, with the highest mean value observed at 72 hai in the 6K + 8Ca treatment. In the other treatments, the mean calcium content peaked at 48 hai and then decreased. A similar pattern in asymptomatic tissue was observed for potassium in the 6K + 8Ca treatment. Fertilization with calcium and potassium directly affected the demand and availability of nutrients at different times during infection. These results demonstrate that plant defence responses and their continuity over time during infection rely on balanced calcium and potassium fertilization because these nutrients are directly involved in plant resistance to the pathogen.  相似文献   
110.
Journal of Bioenergetics and Biomembranes - S-adenosylmethionine (AdoMet) predominantly accumulates in tissues and biological fluids of patients affected by liver dysmethylating diseases,...  相似文献   
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