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71.
Two species of Rhinoestrus (i.e. Rhinoestrus purpureus (Brauer) and Rhinoestrus usbekistanicus Gan) cause nasal myiasis in horses, donkeys and zebras. In the past 15 years myiasis caused by R. purpureus has been reported in Egypt and by R. usbekistanicus in Senegal and Niger, both in horses and in donkeys. With the aim to investigate the presence of this myiasis in autochthonous horses and donkeys from southern Italy and to study the seasonal trend of larval infection, 212 native horses were necropsied in two slaughterhouses in the Apulia region (site A) from January to November 2003, and 120 native horses and two donkeys in one slaughterhouse in Sicily (site B) from January to October 2003. Thirteen of 212 and 5 of 120 horses examined from sites A and B, respectively, were infected by nasal bot fly larvae. Both donkeys examined were positive. Two hundred and thirteen larvae, representing all stages, were collected from the throat region, the turbinates and beyond the lamina cribrosa of the ethmoid bone, in the cerebral cavity. Third larval stages were retrieved from April to September with the highest mean burden in site A in May and in July in site B. The simultaneous presence all three larval stages at site B suggests the existence of two or more overlapping generations. Larvae were identified on the basis of peritreme structures and arrangement of the spines on the dorsal surface of the third segment. Some L3 collected from sites A and B presented morphological characteristics of both R. usbekistanicus and R. purpureus. The presence of mixed features on the L3 of Rhinoestrus collected from the same animals may be explained by the existence of a single species of Rhinoestrus presenting different morphotypes or of two species of Rhinoestrus which are both present in southern Italy since this area is midway between eastern and African countries where these two species have been reported.  相似文献   
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73.
This paper investigates how Food Security (FS) is enacted in a southern region of Italy, characterized by high rates of mafias-related activity, arguing for the inclusion in the research of socio-cultural features and power relationships to explain how Alternative Food Networks (AFNs) can facilitate individual empowerment and community resilience. In fact, while FS entails legality and social justice, AFNs are intended as ‘instrumental value’ to reach the ‘terminal value’ of FS within an urban community in Sicily, as well as the space where citizens can act their individual and collective political food choices. Building on the social psychology literature and on ecologic-psychopolitical models (Christens and Perkins in J Commun Psychol 36(2):214–231, 2008), we discuss the case of Addiopizzo, a citizen project promoting the legality of their AFNs through the rejection of the payment of the pizzo (the protection money asked by racket) in the local food chain. The aim is to problematize the extent to which FS is able to re-localize ‘legal’ food in the market. This was done by reconnecting citizens to their space and territory in a socio-cultural context at risk where agro-food producers, retailers and consumers are not free to fully enact their citizenship agency because of a widespread illegal structure. The research findings show that Addiopizzo project enables citizens to act their social power: agro-food producers and retailers by subscribing to formal requirements based on values that reject racket; consumers by purchasing Addiopizzo labelled products; individuals and groups by participating further open-to-the-public activities that promote everyday politically oriented behaviour. The citizen empowerment and community resilience can be exerted within AFNs as they are interconnected paths of reflexivity and social learning within social adaptation. The paper concludes by advocating the role of urban communities as a pivotal agent to maintain positive social adaptations, where AFNs work as a socio-cultural synthesis of traditional and alternative producer–consumer ways of interaction, which are embodied in the FS value.  相似文献   
74.
Group B Streptococcus (GBS) is a multiserotype bacterial pathogen representing a major cause of life-threatening infections in newborns. To develop a broadly protective vaccine, we analyzed the genome sequences of eight GBS isolates and cloned and tested 312 surface proteins as vaccines. Four proteins elicited protection in mice, and their combination proved highly protective against a large panel of strains, including all circulating serotypes. Protection also correlated with antigen accessibility on the bacterial surface and with the induction of opsonophagocytic antibodies. Multigenome analysis and screening described here represent a powerful strategy for identifying potential vaccine candidates against highly variable pathogens.  相似文献   
75.
Abnormally high spiking activity can damage neurons. Signaling systems to protect neurons from the consequences of abnormal discharge activity have been postulated. We generated conditional mutant mice that lack expression of the cannabinoid receptor type 1 in principal forebrain neurons but not in adjacent inhibitory interneurons. In mutant mice,the excitotoxin kainic acid (KA) induced excessive seizures in vivo. The threshold to KA-induced neuronal excitation in vitro was severely reduced in hippocampal pyramidal neurons of mutants. KA administration rapidly raised hippocampal levels of anandamide and induced protective mechanisms in wild-type principal hippocampal neurons. These protective mechanisms could not be triggered in mutant mice. The endogenous cannabinoid system thus provides on-demand protection against acute excitotoxicity in central nervous system neurons.  相似文献   
76.
Although the voluntary intake of drugs of abuse is a behavior largely preserved throughout phylogeny, it is currently unclear whether pathological drug use ("addiction") can be observed in species other than humans. Here, we report that behaviors that resemble three of the essential diagnostic criteria for addiction appear over time in rats trained to self-administer cocaine. As in humans, this addiction-like behavior is present only in a small proportion of subjects using cocaine and is highly predictive of relapse after withdrawal. These findings provide a new basis for developing a true understanding and treatment of addiction.  相似文献   
77.
We report the incrementally staged design, synthesis, characterization, and operation of a molecular machine that behaves like a nanoscale elevator. The operation of this device, which is made of a platformlike component interlocked with a trifurcated riglike component and is only 3.5 nanometers by 2.5 nanometers in size, relies on the integration of several structural and functional molecular subunits. This molecular elevator is considerably more complex and better organized than previously reported artificial molecular machines. It exhibits a clear-cut on-off reversible behavior, and it could develop forces up to around 200 piconewtons.  相似文献   
78.
A nutritional supplement (Ecotrofin™, by Vetoquinol Italia S.r.l) recommended in ruminants feeding to strengthen the physiological condition and improve digestive performance was tested in 20 pluriparae grazing goats divided in two groups (control and treated) to assess its possible effects on milk yield and quality and to assess eventual adverse effects. Animals from both groups also received 400 g/day of corn meal, and the treated group was supplemented with 20 g/head/day of the nutritional supplement. At the doses suggested by the manufacturer, despite a transient increase after 30 days of supplementation, Ecotrofin™ did not show significant effects on milk yield and, although some changes were found in the fatty acids profile, no significant improvement of MUFA and PUFA, as well as of omega-6:omega-3 ratio and CLA content were seen. Therefore, in our experimental conditions the supplementation of diet with Ecotrofin™ did not appear useful to improve goat's performance. A significant effect on kidney health markers (27 vs. 22.5 for urea and 0.83 vs. 0.76 for creatinine, < 0.05) suggested a beneficial effect on renal function but, since levels fell in the normal ranges in both groups, such hypothesis would need further studies to be addressed.  相似文献   
79.
After flavonol glycosides, monomeric flavan-3-ols, and dimeric and trimeric proanthocyanidins were fractionated from an extract of sea buckthorn (Hippophae rhamnoides) pomace by Sephadex LH-20 gel chromatography, oligomeric proanthocyanidins were eluted. The oligomeric fraction accounted for 84% of the total proanthocyanidins and 75% of the total antioxidant activity of the sea buckthorn pomace extract. To elucidate the structure of the oligomeric fraction, it was depolymerized by acid catalysis in the presence of phloroglucinol. The structure of the resulting flavan-3-ol monomers and flavan-3-ol-phloroglucinol adducts was determined by electrospray ionization mass spectrometry (ESI-MS) and (1)H and (13)C nuclear magnetic resonance (NMR) spectroscopy. Quantitative high-performance liquid chromatography investigations demonstrated (+)-gallocatechin as the predominating subunit in the oligomeric fraction. This observation was confirmed by ESI-MS, matrix-assisted laser desorption/ionization mass spectrometry, and (13)C NMR spectroscopy. The results showed that the majority of the flavan-3-ol subunits possessed a 2,3-trans configuration. The oligomers consisted mainly of prodelphinidin subunits whereas procyanidins were present in smaller amounts, indicating a very uncommon composition of the sea buckthorn proanthocyanidins. The mean degree of polymerization of the oligomeric proanthocyanidins was between 6 and 9.  相似文献   
80.
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