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71.
Significant technological advantages in terms of sweetness synergy and hence cost-saving can be obtained if neohesperidin dihydrochalcone (NHDC) is used in sweetener blends with other intense or bulk sweeteners. The combination of NHDC with sodium saccharin or sodium cyclamate is an excellent method to improve the water solubility at room temperature of NHDC. In the case of NHDC-sodium saccharin, two different methods for blend preparation, a simple mixture and a cosolubilized mixture, can be used, with similar results obtained for solubility and solution stability properties. To improve temporally the water solubility of NHDC in combination with sodium cyclamate, it is absolutely necessary to prepare cosolubilized blends.  相似文献   
72.
Must obtained from Airén grapes was fermented in the presence of wood chips (4 and 7 g/L) of either French oak (from Vosges, central France, and Allier zones) or American oak. Fermentation yields were higher than in the control fermentations carried out in the absence of wood, and production of volatile substances during fermentation (alcohols, esters, and acetates) was also higher. The volatile substances that leached out of the wood were analyzed by GC-MS-SIR. The results showed that their concentrations depended on the type and amount of the oak; some of these substances were consumed in part by the yeasts during fermentation. A taste panel favorably assessed the wines produced by fermentation in the presence of oak chips, which retained part of the must original fruity aroma.  相似文献   
73.
The release of lipids during the aging of sparkling wines in contact with yeast can influence wine sensory attributes and, especially, foam characteristics. Model systems allow study of the autolysis process in a reasonable period of time compared to natural conditions, at which it can last several months. In this paper, the release of the different classes of lipids during the autolysis of three commercial yeast strains in a model wine medium has been monitored. Due to the absence of accurate quantitative methods, an HPLC method for separating and quantifying the different neutral and polar yeast lipid classes was developed. Lipids were eluted through a YMC PVA-Sil column with a complex solvent mixture. Detection was carried out with a light-scattering detector. The yeasts were suspended in the model wine buffer and incubated at 30 degrees C for up to 12 days. A release of triacylglycerols, 1,3-diacylglycerols, 2-monoacylglycerols, free fatty acids, sterol esters, and sterols was observed over the first 2 days, a period that corresponded to the maximum loss of yeast viability. A decrease in most of these lipids was observed from day 2, possibly indicative of the release of yeast hydrolytic enzymes due to the breakdown of the cell wall. Phospholipids were not detected in any of the autolysates. The mean lipid content in the autolysates as a percentage of the total lipid content in the yeasts was 8.6% for sterol esters, 3.8% for sterols, 2% for triacylglycerols, and <2% for 1,3-diacylglycerols and free fatty acids.  相似文献   
74.
The persistence of two herbicides, simazine and terbuthylazine, and appearance of their principal dealkylated chloro-s-triazine metabolites have been studied in agricultural soil after the addition of urban sewage sludge as organic amendment. Both herbicides and metabolites were monitored during long-term laboratory incubation (140 days) and analyzed by gas chromatography with a nitrogen-phosphorus detector (GC-NPD). Residues were confirmed by gas chromatography with a mass selective detector (GC-MSD). A sonication microextraction method was used to extract the compounds. The organic amendments used were urban sewage sludge and the humic fraction of this sludge, to increase the organic matter content of the soil from 1% to 2%. For both compounds, simazine and terbuthylazine, the degradation began earlier in the amended soils. Simazine showed a higher dissipation rate than terbuthylazine, the percentage of the former at the end of the experiment being lower than 2% in all cases, while for terbuthylazine the corresponding percentage ranged from 5% to 46%. Organic amendment, mainly its humic fraction, caused a certain stabilization of terbuthylazine in the soil, but did not greatly influence the residual amount of simazine at the end of the experiment. The periodic aeration of the soil caused a greater degradation in the case of terbuthylazine. Only mono-deethylsimazine and deethylterbuthylazine were isolated from the soil during the time the experiment lasted, while the di-deethylated metabolite of simazine was not found.  相似文献   
75.
76.
当前,人工繁殖对增殖里海鲟鱼类资源的作用很大,但人工繁殖效果及其对增加鲟鱼类种群数量的作用往往取决于繁殖场放流的幼鲟的质量。在这方面,从鲟鱼类生物学特性、从环境条件对放流幼鲟的影响来考察,幼鲟入海后的成活率高低便是个关键问题。  相似文献   
77.
Canine monocytic ehrlichiosis (CME) is a tick-borne disease caused by the rickettsia Ehrlichia canis. Ocular lesions are a common feature of the disease and can be present in all stages. The purpose of this retrospective study was to determine the prevalence, type and response to treatment of ocular lesions associated with monocytic ehrlichiosis in 46 affected dogs presented to the Autonomous University of Barcelona-Veterinary Teaching Hospital (UAB-VTH) from January 2000 to December 2002. Dogs were included in the study only if they had a positive serologic test for E. canis and information about the clinical outcome was available. Eighteen breeds were represented, with the German Shepherd dog (n = 6) being the most common. There were 25 intact and three castrated males, and 16 intact and two neutered females. Twenty dogs (43.4%) were between 5 and 10 years old. Seventeen dogs (37% of all cases of monocytic ehrlichiosis diagnosed during the study period) had ocular signs, and 11 dogs (64.7% of the ocular cases) had only ocular lesions without apparent systemic signs. Exudative retinal detachment was the most common ocular manifestation; other prevalent findings included anterior exudative uveitis and optic neuritis. Five of the 17 cases with ocular lesions (29.4%) had ocular bleeding disorders (hyphema or retinal hemorrhages). All the dogs with ocular disease presented with bilateral signs. Dogs with posterior segment disease had titers against E. canis that were > or = 1 : 320, while lower titers were noted in dogs with anterior exudative uveitis. Two dogs presented with chronic autoimmune panuveitis after ehrlichiosis treatment. Canine ehrlichiosis should be considered in the differential diagnosis of exudative retinal detachment and anterior uveal inflammatory lesions.  相似文献   
78.
An 8-year-old, spayed female Domestic Short-haired cat was referred for further evaluation of chronic lymphocytic-plasmacytic stomatitis and bilateral ocular disease. The cat had been treated with systemic glucocorticoids for several months. Initial ophthalmic examination revealed bilateral deep stromal corneal ulcers, exudative panuveitis and secondary glaucoma. Mature mild neutrophilia and monocytosis were detected on complete blood cell count. Abnormalities in the serum profile were hyperglycemia, mild azotemia, hyperglobulinemia and moderate polyclonal gammapathy. Urinalysis revealed glucosuria without ketonuria. Diabetes mellitus was diagnosed and treatment with long-acting insulin was started. An enzyme-linked immunosorbent assay was highly positive for leishmaniasis, and treatment with allopurinol was started. Although specific topical treatment was applied, melting ulcers progressed to corneal perforation and both eyes were enucleated. Ocular histology showed large numbers of intracellular organisms compatible with amastigotes of the genus Leishmania located in the uveal tract, cornea, sclera and retina. Results of inmunohistochemistry staining on ocular samples were positive for Leishmania. Bone marrow cytology demonstrated numerous macrophages with intracytoplasmatic Leishmania. Polymerase chain reaction results on bone marrow for Leishmania were positive. Three weeks later, hypoglycemic episodes permitted withdrawal of the insulin therapy. To the authors' knowledge this is the first case of ocular and visceral leishmaniasis diagnosed in vivo and under systemic treatment in a cat.  相似文献   
79.
The aim of the study was to investigate the influence of administration of probiotic bacteria on morphology of the gastrointestinal tract, liver and pancreas. The experiment was performed on 15 piglets at the age from 3 to 35 days, intragastrically administered with Bifidobacterium breve, B. animalis, and Lactobacillus acidophilus bacteria. In all piglets examined, the development of the gastrointestinal tract, liver and pancreas was observed to progress normally. After microflora administration to the piglets, an increase in the number of fibrocytes and fibroblasts was observed in the mucosa lamina propria of stomach and intestines. An increase was also reported in the number and activation of endocrine cells in the stomach and small intestines. The activity of alkaline and acid phosphatases, as well as succinic (SDH) and lactic (LDH) dehydrogenases, was found to be higher after the administration of probiotics. The administration of bacteria, especially of Lactobacillus acidophilus, caused an increase in the number of lymphocytes and lymphoid cells in lamina propria and intraepithelial lymphocytes in the small intestine. Enhanced proliferation of crypt cells was observed in the crypts of intestinal glands; however, there were no statistically significant differences in the PCNA index between the control and probiotic-administered groups. The performed study showed that the administration of probiotic bacteria has no negative impact on the morphology of the gastrointestinal tract, liver and pancreas and is found beneficial to its functioning and immune processes.  相似文献   
80.
Ovine pulmonary adenocarcinoma (OPA) is a naturally occurring contagious lung neoplasia caused by jaagsiekte sheep retrovirus (JSRV). Although no specific circulating antibodies against the virus can be detected in infected sheep, JSRV proviral DNA sequences can be found in peripheral blood leukocytes (PBLs) in clinically affected and in a proportion of in contact animals. In this study, existing hemi-nested PCR procedure is compared with a new one-step PCR technique that was developed to minimise potential DNA contamination and reduce sample and reagent handling. Different blood preparations were assessed and the best results were achieved on DNA prepared from buffy coat. The sensitivity of this PCR was lower in JSRV infected sheep without lesions of OPA than in clinically affected sheep, which indicate that this PCR may not be not fully appropriate for screening of individual sheep, but rather to provide results at flock level. This PCR is the only currently available blood test for detection of JSRV infected sheep and may be useful in epidemiological studies and in control programmes of OPA.  相似文献   
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