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981.
This study was carried out to establish the changes in the free amino acid contents of floral honeys, honeydew honeys, and blend honeys during storage at room temperature and to test the capacity of the amino acids to distinguish the origin of the honeys after storage. For this purpose, 54 artisanal honeys (39 floral, 5 honeydew, and 10 blend) were studied. Samples were taken from recently collected honeys and at 3, 6, 9, 12, 16, 20, and 24 months after harvesting. The contents of most of the free amino acids were found to decrease with storage time, with the greatest reduction observed in the first 9 months. The contents of the amino acids aspartic acid, beta-alanine, and proline increased in the first few months after storage, reaching maximum values at 6 months, suggesting the possible existence of enzymatic activities. The application of stepwise discriminant analysis to the free amino acid content data demonstrated that the contents of the amino acids valine, beta-alanine, gamma-aminobutyric acid, serine, isoleucine, alpha-alanine, ornithine, and glutamine correctly assigned 87% of honeys to their group of origin: floral, honeydew, or blend.  相似文献   
982.
The capacity of alquitara (a traditional distillation system) to produce cider brandies is evaluated. To do so, the chemical composition of 12 fractions obtained during the distillation process and the cider brandies obtained from five ciders were analyzed (alcohol strength, methanol, volatile substances, furfural, and metals), taking into account European and Spanish legislation. During the course of distillation, an important increase in methanol, furfural, 2-phenylethanol, and metals in the last fractions was observed, while fusel oils were more abundant in the first fractions collected. Only acetaldehyde behaved differently, showing a minimum concentration in the middle fractions that might be explained by its formation on the surface of alquitara. On the other hand, the final distillates obtained by means of this method complied with the considered regulations. Worth highlighting in this regard are the low levels of a potential toxin such as methanol, as well as the detection of a constant ratio for methanol, ethanol, and fusel oil for the pairs of cider/spirits analyzed, which could be interpreted as an indication of good uniformity in the distillation system and method, thus guaranteeing product quality.  相似文献   
983.
A structure-function study was carried out to increase knowledge of how glycosidic linkages and molecular weights of carbohydrates contribute toward the selectivity of fermentation by gut bacteria. Oligosaccharides with maltose as the common carbohydrate source were used. Potentially prebiotic alternansucrase and dextransucrase maltose acceptor products were synthesized and separated into different molecular weights using a Bio-gel P2 column. These fractions were characterized by matrix-assisted laser desorption/ionization time-of-flight. Nonprebiotic maltooligosaccharides with degrees of polymerization (DP) from three to seven were commercially obtained for comparison. Growth selectivity of fecal bacteria on these oligosaccharides was studied using an anaerobic in vitro fermentation method. In general, carbohydrates of DP3 showed the highest selectivity towards bifidobacteria; however, oligosaccharides with a higher molecular weight (DP6-DP7) also resulted in a selective fermentation. Oligosaccharides with DPs above seven did not promote the growth of "beneficial" bacteria. The knowledge of how specific structures modify the gut microflora could help to find new prebiotic oligosaccharides.  相似文献   
984.
The health of 22 free-ranging adult rheas (Rhea americana) examined and sampled during a translocation/reintroduction project and six juvenile rheas kept in semicaptivity was investigated, and details of their haematology and plasma biochemistry are presented. Serological testing for antibodies to infectious agents was negative for infectious laryngotracheitis, avian adenovirus, avian influenza, avian reovirus, infectious bursal disease, infectious bronchitis virus, paramyxovirus types 1, 2, and 3, fowlpox and Salmonella Pullorum. Antibodies to Chlamydophila species were found in 25 of 27 of the birds, and 22 of 25 had antibodies to Aspergillus species. Ova of gastrointestinal nematodes of the genus Capillaria were identified, and the anoplocephalid cestode Monoecocestus cf rheiphilus was identified in R americana for the first time.  相似文献   
985.
986.
987.
Clonidine (CL) is a alpha2-adrenergic agonist that produces analgesia in animals and humans by a non-opiate alpha2-adrenergic action in the spinal cord dorsal horn. The objective of this prospective randomized study was to investigate the clinical effects of CL/lidocaine (LD) combination administered by the subarachnoid route in sheep. Each sheep received each of three treatments, at no shorter than weekly intervals. Treatments consisted of 0.003 mg/kg CL, 1.2 mg/kg LD and a combination of CL (0.003 mg/kg) and LD (1.2 mg/kg) (CLLD). Subarachnoid injections were given in all animals between the last lumbar and first sacral vertebra. Heart rate (HR), arterial pressures, respiratory rate, rectal temperature, analgesia, sedation, and motor blockade were determined before drug administration (basal) and 5, 10, 15 and 30 min after drug administration, and at 30-min intervals until loss of analgesia occurred. The duration of analgesia after subarachnoid CLLD administration was 187 +/- 24 min (mean +/- SD), i.e. more than twice of that obtained with CL (99 +/- 19 min) or LD (55 +/- 4.4 min) alone. In all sheep, CL, administered either alone or with LD, induced moderate sedation. After subarachnoid administration of three treatments, all sheep had ataxia and subsequent sternal recumbency. The CL treatment causes decreases in blood pressure (diastolic arterial pressure and mean arterial pressure) and HR. Data suggest that the CLLD combination could be used subarachnoidally in sheep requiring prolonged surgery.  相似文献   
988.
Gemcitabine is a relatively new chemotherapeutic compound used to treat a variety of cancers in dogs. Previous work presented in a companion paper explored the plasma kinetics of gemcitabine and its inactive metabolite, 2',2'-difluorodeoxyuridine (dFdU), in dogs after an intravenous bolus gemcitabine dose and demonstrated the saturation of intracellular dFdCTP (2',2'-difluorodeoxycytidine 5'-triphosphate) occurs in vitro with increasing extracellular gemcitabine exposure in canine melanoma cells. In this study, the plasma pharmacokinetics (PKs) of gemcitabine and dFdU are further explored after gemcitabine doses of 10, 30, and 60 mg/kg administered by intravenous infusion with a loading dose. Gemcitabine displayed linear PKs, while the kinetics of dFdU were not dose proportional. The overall clearance, volume of distribution at steady-state, and terminal elimination half-life (t(1/2)) for gemcitabine were 0.421 L/h.kg, 0.822 L/kg, and 1.49 h, respectively. Plasma concentrations of dFdU peaked at approximately 2 h postdosing and had a t(1/2) of 14.9 h.  相似文献   
989.
The objective of this study was to evaluate dexmedetomidine as a premedicant in dogs prior to propofol-desflurane anaesthesia, and to compare it with medetomidine. Six healthy dogs were anaesthetized. Each dog received intravenously (i.v.) five preanaesthetic protocols: D1 (dexmedetomidine, 1 microg/kg, i.v.), D2 (dexmedetomidine, 2 microg/kg, i.v.), M1 (medetomidine, 1 microg/kg, i.v.), M2 (medetomidine, 2 microg/kg, i.v.), or M4 (medetomidine, 4 microg/kg, i.v.). Anaesthesia was induced with propofol (2.3-3.3 mg/kg) and maintained with desflurane. The following variables were studied: heart rate (HR), mean arterial pressure, systolic arterial pressure, diastolic arterial pressure, respiratory rate (RR), arterial oxygen saturation, end-tidal CO2, end-tidal concentration of desflurane (EtDES) required for maintenance of anaesthesia and tidal volume. Arterial blood pH (pHa) and arterial blood gas tensions (PaO2, PaCO2) were measured during anaesthesia. Time to extubation, time to sternal recumbency and time to standing were also recorded. HR and RR decreased significantly during sedation in all protocols. Cardiorespiratory variables during anaesthesia were statistically similar for all protocols. EtDES was significantly different between D1 (8.1%) and D2 (7.5%), and between all doses of medetomidine. Desflurane requirements were similar for D1 and M2, and for D2 and M4 protocols. No statistical differences were observed in recovery times. The combination of dexmedetomidine, propofol and desflurane appears to be effective for induction and maintenance of general anaesthesia in healthy dogs.  相似文献   
990.
A method for the evaluation of splenic cellularity using samples collected by fine-needle aspirative biopsy was standardized in this work. The procedure includes erythrocyte lysing, preparation of cytospin films and staining by histochemical and immunocytochemical techniques. The cellular profiles of spleen preparations were compared with those observed in peripheral blood samples subjected to the same procedure. Two groups were compared, one consisting of 14 healthy uninfected and the other of 15 polysymptomatic Leishmania chagasi/infantum-infected dogs, from an endemic area for visceral leishmaniosis. Cell populations were identified by conventional hematoxilin-eosin and Wright' stainings, and by immunocytochemistry using monoclonal antibodies against canine CD45RA and CD45RB, phagocytes and a pan-leukocyte antigen. Larger neutrophil (P < 0.0001) and monocyte/macrophage (P = 0.0036) relative counts and lower lymphocyte relative counts (P < 0.0001) were found in the spleen, and not in the blood, of the animals with leishmaniosis than in those of the healthy animals. The proportions of CD45RB+ cells were higher, and of CD45RA+ cells were lower, both in the spleen and in the blood of animals with leishmaniosis than in those of healthy dogs (P < 0.05). Additionally, hematoxilin-eosin-stained cytospins of spleen aspirates from Leishmania-infected animals permitted the easy visualization of amastigote forms inside phagocytes, under light microscopy.  相似文献   
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