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171.
Nuclear magnetic resonance (NMR) spectroscopy combined with multivariate data analysis (MVA) was used to investigate the molecular components of the aqueous extract of samples of bottarga, that is, salted and dried mullet (Mugil cephalus) roe, manufactured in Sardinia (Italy) from mullets of known and unknown geographical provenience. Principal component analysis (PCA) applied to the processed (1)H NMR spectra indicated that samples tend to cluster according to their geographical origin and also on the basis of storage and manufacturing procedures. The most important metabolites that characterized grouping of samples are the free amino acids methionine (Met), glutamate (Glu), histidine (His), phenylalanine (Phe), tyrosine (Tyr), and isoleucine (Ile); trimethylamine (TMA) and dimethylamine (DMA), both biomarkers of degradation; nucleotides and derivatives; choline (Cho) and phosphorylcholine (P-cho); and lactate (Lac).  相似文献   
172.
The study of the mechanisms involved in phenotypic adaptations or plasticity to environmental stressors may serve to evaluate contemporary ecological and evolutionary dynamics in threatened or growing wildlife populations. By addressing human disturbance as a main stressor agent, we investigated antipredator response (flushing distance), social behavior (degree of gregarism), health (fecal pathogens), and endocrine status (fecal corticosterone levels) as potential mechanisms that permit birds to cope with anthropogenic impact in tourist areas. Our study models were species that are neither urbanized nor invasive, and that are typical of the high mountains of the Palearctic: the Alpine and the Red-billed chough (Pyrrhocorax graculus and P. pyrrhocorax), and the surrounding alpine bird community. Both chough species showed habituation, reduced flushing distances, fewer parasites and lower corticosterone levels in tourist than in non-tourist sites, and a significant variation in gregarious behavior. Behavioral and physiological adjustments permitted these corvids to optimize resource exploitation depending on habitat quality and in conditions of continuous disturbance. Human-induced changes in chough social behavior had no effect on local avian species richness, a surrogate measure for community diversity. Irrespectively of chough aggregations, bird diversity decreased significantly in recreational areas, thus not all community members tolerated human impact as choughs did. Our findings suggest that species that manage to coexist with humans primarily adjust traits that influence ecological interactions (social, foraging or antipredatory responses) and that vary rapidly (learned behaviors and physiological mechanisms that promote homeostasis).  相似文献   
173.
Lingual lesions are relatively uncommon in dogs and are mostly represented by neoplasms and glossitis secondary to trauma or infections. Reactive histiocytosis is an uncommon, poorly understood, reactive disorder characterized by proliferation of activated, interstitial, dendritic, antigen-presenting cells associated with lymphocytes and neutrophils with a specific angiocentric orientation and occasional angioinvasion and angiodestruction. Clinically, the disease has a waxing and waning behavior with possible response to treatment and regression, or progression to multiple lesions and internal organ involvement. This case report describes an unusual sublingual presentation of reactive histiocytosis in a Miniature Pinscher dog. The diagnosis was obtained by clinical and histopathological exclusion of other causes, detection of the characteristic microscopic growth pattern, and by immunocytochemistry. Histiocytic cells were vimentin, CD18, CD11c, and CD1c positive consistent with a dendritic cell origin. Anti-BCG stain (Bacillus Calmette and Guerin) was negative for etiological agents. The dog was treated with oral administration of tetracycline and niacinamide during an 8-month period. There was no indication of recurrence of the sublingual mass 2-years following treatment.  相似文献   
174.
An indirect organogenesis regeneration protocol for Opuntia ficus-indica (L.) Mill var “Blanco sin Espinas” is described. One centimeter square cladode explants sections from previously micropropagated prickly pear plants were cultured in Murashige and Skoog (MS) basal medium supplemented with 20 different combinations of 2,4-dichlorophenoxy acetic acid (2,4-D) and benzyladenine (BA). The best calli induction and regeneration response were observed when 2.26 μM 2,4-D and 2.21 μM BA combination was applied to the nopal explants. Regenerating calli was capable of forming new buds when transferred to MS basal medium supplemented with 0.5 μM BA (proliferation medium). Shoot elongation and rooting were achieved on MS medium without plant growth regulators. Excellent acclimatization to greenhouse conditions was observed for all transferred plantlets. By this procedure no morphological differences were observed between the regenerated and mother plants. This protocol may be also utilized to carry out plant regeneration after genetic transformation, in order to develop transformed plants without the presence of chimeric zones.  相似文献   
175.
The aim of this paper is to evaluate the effect of research and development (R&D) on productivity by taking into account productivity spillovers. To this end, by using a sample of Italian manufacturing firms over the period 2004–2006 provided by the Xth UniCredit‐Capitalia survey (2008), we have analyzed the role of R&D in firm productivity by using a spatial autoregressive model. In so doing, we have allowed the productivity of each firm to be affected by the productivity of nearby firms. Results show that R&D significantly affects Italian firm productivity and that productivity spillovers across firms matter. Moreover, productivity is found to be positively affected by intrasectoral R&D spillovers, while intersectoral R&D spillovers do not have a significant effect.  相似文献   
176.
The quality of protein concentrates coming from conventional and non-conventional vegetable sources was evaluated. The protein quality was assessed by the multi-point assay RPV. Whole body weight gain, weight gain corrected for the gastrointestinal content (G.I.), total body nitrogen and total liver nitrogen were used as response parameters. The various protein sources ranked differently depending upon the response parameters utilized, but a great majority of the sources had a good nutritional value (over 0.5). The gastrointestinal content is one of the principal factors responsible for the differences found. However, even after correcting for the G.I. content, some differences remained. For the various protein sources, the nitrogen deposition in the liver correlates satisfactorily with the whole body nitrogen deposition, if in the calculation of the regression line, the data for faba bean and tobacco were omitted (respectivelyr=0.610 andr=0.925). On the whole, these data indicate that most plant protein concentrates in suitable combinations and properly processed, may become a promising alternative to animal proteins.  相似文献   
177.
Twenty-two dogs and cats with symptomatic renal or hepatic cysts that had undergone ultrasound-assisted drainage and alcoholization were retrospectively evaluated. Common presenting complaints were anorexia, reluctance to move, and vomiting. Abdominal pain was observed in all cases. Systemic hypertension was identified in four dogs and four cats with renal cysts. Cyst drainage and alcoholization were achieved without complications in 19 animals, and all clinical signs resolved after the procedure. In three cases, transient bleeding was observed during alcoholization, and the procedure was interrupted. Blood pressure normalized in the four dogs with renal cysts, but it remained elevated in the four cats.  相似文献   
178.
Neosporosis by Neospora caninum causes losses to livestock production through abortion in cattle while, in dogs, it induces neuromuscolar disease. This study investigated neosporosis seroprevalence associated risk factors (including the seropositivity to leishmaniosis) in dogs of southern Italy, determined the prevalence of N. caninum oocyst shedding and examined the relationship between seroprevalence of neosporosis in farm dogs and cattle. Using an inhibition ELISA, 20.9% of 306 dogs had percent inhibition values >10 (indicative of exposure) and farm dogs had a significantly (p<0.001) higher seroprevalence than dogs in a rescue kennel. Whilst N. caninum seroprevalence was associated with increasing age in dogs (p< or =0.01) there was no association between seropositivity for N. caninum and for Leishmania infantum. Oocysts of N. caninum were not detected in faecal samples from 230 dogs including 160 farm dogs. The results indicated that neosporosis infection is common in southern Italy both in dogs and in cattle and that dogs at higher risk of exposure are free-ranging ones living in farms. The lack of correlation between canine seroprevalence for N. caninum and L. infantum assumes a particular significance in an endemic area for leishmaniosis.  相似文献   
179.
Administration of recombinant feline interferon-omega (rFeIFN) has been proposed for the prophylaxis of canine and feline parvovirosis. In the present study, the influence of the administration of rFeIFN on blood markers of inflammation (alpha-globulins, alpha(1)-acid glycoprotein) and immune system activation (gamma-globulins, IgG, IgM, specific anti-feline parvovirus IgG or IgM) was evaluated in a cattery developing an outbreak of feline panleukopenia due to feline parvovirus (FPV) infection few days after initial administration of rFeIFN. Kittens (n=23) were injected with rFeIFN (1MU/kg subcutaneously, once a day for 3 days) and their blood parameters were compared with those of 17 untreated cats. Cats that survived the outbreak were vaccinated and re-sampled 1 month after the last rFeIFN administration. Time of emergence of clinical signs and survival rate were not significantly different between the two groups. Controls and treated cats surviving the infection had high levels of gamma-globulins, total- and anti-FPV specific IgGs, likely due to passive transfer of maternal immunity. Compared to controls, treated kittens had lower levels of alpha(1)-globulins and higher mean values of gamma-globulins and immunoglobulins. Data from samples collected after vaccination revealed a higher level of gamma-globulins, total- and anti-FPV specific IgGs in treated kittens, compared with controls, suggesting that rFeIFN stimulates antibody production. Based on this results, rFeIFN should be administered to the queen, to increase passive maternal immunity, or to kittens before introduction in a potentially contaminated environment.  相似文献   
180.
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