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91.
The free volatiles, as well as those released from the glycosidically bound forms by enzyme hydrolysis, have been analyzed to chracterize young Tannat wines from two successive vintages. The Tannat wine showed some aroma profile peculiarities detected in the free forms but, above all, in the bound fraction for the level and profile of the norisoprenoidic fraction. Among the free volatile compunds, a rather low content of C(6) alcohols with a prevalence of cis-3-hexen-1-ol on the trans form and sometimes a remarkable level of trans-2-hexen-1-ol seem to be typical for the variety. C(13)-norisoprenoidic and monoterpenic volatiles made up approximately 42% of the total level of the volatiles observed in the glycosidase enzyme-released fraction. The other volatiles were C(6) alcohols (6%) and benzenoid compounds (51%). The dominating monoterpene alcohols were the cis and trans isomers of 3,7-dimethyl-1,6-octadiene-3,8-diol (8-hydroxylinalool). The C(13)-norisoprenoid pattern was composed by 3-hydroxy-beta-damascone, 3-oxo-alpha-ionol, vomifoliol, 4-oxo-beta-ionol, 3-oxo-7,8-dihydro-alpha-ionol, 4-oxo-7,8-dihydro-beta-ionol, grasshopper ketone, and 7,8-dihydrovomifoliol.  相似文献   
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The modification of the biobased polymer chitosan is a broad and widely studied field. Herein, an insight into the hydrophobization of low-molecular-weight chitosan by substitution of amino functionalities with hexanoyl chloride is reported. Thereby, the influence of the pH of the reaction media was investigated. Further, methods for the determination of the degree of substitution based on 1H-NMR, FTIR, and potentiometric titration were compared and discussed regarding their accuracy and precision. 1H-NMR was the most accurate method, while FTIR and the potentiometric titration, though precise and reproducible, underlie the influence of complete protonation and solubility issues. Additionally, the impact of the pH variation during the synthesis on the properties of the samples was investigated by Cd2+ sorption experiments. The adjusted pH values during the synthesis and, therefore, the obtained degrees of substitution possessed a strong impact on the adsorption properties of the final material.  相似文献   
93.
Paenibacillus larvae is a gram-positive spore-forming bacteria, causative agent of American Foulbrood (AFB), a severe disease affecting larvae of the honeybee Apis mellifera. In an attempt to detect potential virulence factors secreted by P. larvae, we identified an enolase among different secreted proteins. Although this protein is a cytosolic enzyme involved in glycolytic pathways, it has been related to virulence. The aim of the present work was to evaluate its role during the infection of honeybee larvae. Toxicity assays showed that enolase was highly toxic and immunogenic to honeybee larvae. Its production was detected inside P. larvae vegetative cells, on the surface of P. larvae spores and secreted to the external growth medium. P. larvae enolase production was also confirmed in vivo, during the infection of honeybee larvae. This protein was able to hydrolyze milk proteins as described for P. larvae, suggesting that could be involved in larval degradation, maybe through the plasmin(ogen) system. These results suggest that P. larvae enolase may have a role in virulence and could contribute to a general insight about insect-pathogen interaction mechanisms.  相似文献   
94.
This paper describes a cat with severe localised infections with Cryptococcus neoformans/gattii species complex and Mycobacterium avium affecting the subcutis and underlying fascia and bone of the right pelvic limb. The simultaneous isolation of both pathogens in this patient was unexpected and posed unique issues concerning both diagnosis and clinical management. The aetiopathogenesis of this infection is discussed in relation to aspects of diagnosis and therapy.  相似文献   
95.
Objective To compare and correlate right atrial pressure, which represents central venous pressure (CVP) to jugular vein pressure (JVP) in laterally recumbent horses under anesthesia. Study design Retrospective clinical trial. Animals Seven adult healthy horses (411 ± 8.7 kg). Methods Horses were sedated with IV xylazine and anesthesia was obtained with IV ketamine and diazepam. Anesthesia was maintained with sevoflurane in oxygen. All horses were positioned in left lateral recumbency. An 8F catheter introducer was inserted into the right jugular vein to measure JVP. An 8F catheter introducer was inserted into the left jugular vein to be used as the port for a 7F 110 cm catheter that reached the right atrium to measure CVP. Both, CVP and JVP were measured simultaneously with a water calibrated aneroid manometer using the sternum as the 0 cmH2O reference point. Measurements were compared using Spearman correlation and the Bland‐Altman plot. Results Twenty paired samples were obtained over a period of 2 hours. The CVP ranged from 7 to 31 cmH2O, while the JVP ranged from 5 to 30 cmH2O. The Spearman correlation coefficient indicated that CVP and JVP had a strong correlation with r = 0.88. The Bland‐Altman plot showed a bias of 0.7 cmH2O. Conclusion and clinical relevance Jugular vein pressure showed a strong correlation with CVP in healthy, euvolemic, laterally recumbent anesthetized adult horses. Thus, JVP cannot replace CVP but it may be used clinically to monitor CVP in laterally recumbent horses.  相似文献   
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A species of Hepatozoon closely related to Hepatozoon felis found in the skeletal and cardiac muscle of a wild Pampas gray fox (Lycalopex gymnocercus) is described. The fox was euthanized after showing severe incoordination. On necropsy and histopathology there was bilateral, diffuse, severe, sub-acute, necrotizing bronchointerstitial pneumonia, with intracytoplasmic and intranuclear eosinophilic inclusion bodies. Canine distemper virus was detected by immunohistochemistry in the bronchiolar epithelium, syncytial cells, alveolar macrophages and pneumocytes. The skeletal muscle and myocardium contained multiple round to oval protozoan cysts ranging from 64 μm × 75 μm to 98 μm × 122 μm, with a central eosinophilic meront-like core surrounded by concentric rings of mucinous material resembling Hepatozoon americanum cysts but smaller in size. Macrophages within rare pyogranulomas and monocytes/macrophages in adjacent sinusoidal blood vessels in the skeletal muscle contained intracytoplasmic round protozoa consistent with merozoites or developing gamonts of Hepatozoon. Hepatozoon sp. infection was confirmed by PCR of skeletal muscle and the sequenced 18S rRNA PCR product was found to be 99% identical to H. felis by BLAST analysis and deposited in GenBank as accession number HQ020489. It clustered together in the phylogenetic analysis with published H. felis sequences and separately from H. canis, H. americanum and other Hepatozoon species. However, the close relatedness of the fox Hepatozoon to H. felis does not rule out infection with a different and possibly unknown Hepatozoon species.  相似文献   
100.
Fishing tourism is growing steadily in Brazil. Artisanal fishers meeting the demand for recreational fishing are capturing live juvenile shrimp in the estuaries and selling them for live bait, preventing the recruitment of a larger contingent into the ocean. This study compares the efficiency of using lambari, Deuterodon iguape Eigenmann, as live bait with the shrimp, Penaeus schmitti Burkenroad, while fishing for common snook (Centropomus spp.), as well as to evaluate the swimming behaviour of D. iguape in different salinities. The results showed that there was no significant difference between the live baits used (P. schmitti vs D. iguape). The month, the period of the day and salinity presented differences. The size of the species did not depend on the type of bait used. There was no statistical difference in swimming behaviour, but there was a trend of increased speed and displacement in the group exposed to a salinity of 10 g/L. In conclusion, D. iguape appears as effective as P. schmitti and can be successfully used as live bait; and from an ecological point of view, it reduces the impact of fishing on juvenile shrimp.  相似文献   
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