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排序方式: 共有329条查询结果,搜索用时 78 毫秒
41.
42.
Steinberg TA Boettcher IC Matiasek K Hirschvogel K Hartmann K Kunz A Kuntz A Fischer A 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2008,37(2):207-216
BACKGROUND: Inflammation of the central nervous system (CNS) is a frequent condition in cats but etiology often remains unsolved. Routine cerebrospinal fluid (CSF) analysis can be extended through the calculation of the albumin quotient (Q(alb)), a marker of the integrity of the blood-brain barrier (BBB), and IgG index, an estimate of intrathecal IgG synthesis. OBJECTIVES: The purpose of this study was to validate nephelometric methods for CSF protein analysis, and to use the Q(alb) and IgG index to discriminate blood- and brain-derived immunoglobulin fractions in cats with feline infectious peritonitis (FIP). METHODS: Cats presented to our clinic between 2001 and 2005 were included in the study based on clinical and laboratory data and histopathologic findings at necropsy. Cats were grouped as having nonneurologic disease (controls; n=37), brain tumors (n=8), FIP involving the CNS (n=12), and extraneural FIP (n=12). CSF-total protein (TP) was measured and albumin and IgG concentrations were measured in paired CSF/serum samples; Q(alb) and IgG index were calculated. Intraassay and interassay precision of the nephelometric assays were determined using pooled samples. RESULTS: Coefficients of variation for the nephelometric assays ranged from 2.7% to 7.2%. In control cats, CSF-TP concentration ranged from 0.06 to 0.36 g/L, Q(alb) ranged from 0.6 to 5.7 x 10(-3), and IgG index ranged from 0.3 to 0.6. Q(alb) and IgG index were significantly higher in cats with brain tumors and cats with CNS-FIP compared with other groups. Compared with control cats, pleocytosis was evident in 8 of 12 (67%) cats and CSF-TP was increased in 3 of 12 (25%) cats with CNS-FIP. CONCLUSION: Nephelometry is a reliable method for measurement of CSF protein, albumin, and IgG in cats. The Q(alb) and IgG index did not identify a CSF protein pattern specific for BBB dysfunction or intrathecal IgG synthesis in cats with CNS-FIP. 相似文献
43.
Sánchez-Carvajal Jose M. Rodríguez-Gómez Irene M. Carrasco Librado Barranco Inmaculada Álvarez Belén Domínguez Javier Salguero Francisco J. Gómez-Laguna Jaime 《Veterinary research communications》2019,43(3):187-195
Veterinary Research Communications - The emergence of virulent strains of porcine reproductive and respiratory syndrome virus (PRRSV), causing atypical and severe outbreaks, has been notified... 相似文献
44.
Dengsheng Sun Xiao Jin Irene Camerlink Manman Tong Junling Su Fei Zhao Sumei Yan Binlin Shi 《Journal of animal physiology and animal nutrition》2019,103(3):738-746
Dietary Yucca schidigera extract (YSE) could enhance immune function in broilers, which was attributed primarily to its saponin components. However, YSE also contains phenolic compounds which possess antioxidant ability. This study tested the effects of YSE on growth performance of broilers, its antioxidative enzyme activities and corresponding gene expressions in the small intestine. A total of 128 15‐day‐old broilers were randomly assigned to 4 treatments: corn‐soya bean meal as the basal control diet or the basal diet containing either 100, 200 or 300 mg/kg of YSE. Each treatment consisted of four replicate pens with eight broilers per pen. The experiment lasted 28 days which was divided into a grower period (day: 15–28) and a finisher period (day: 29–42). On day 28 and day 42 body weight (BW), feed intake (FI) and feed conversion rate (FCR) were recorded. Duodenum, jejunum and ileum were collected to analyse superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activities, malondialdehyde (MDA) concentrations, total antioxidant capacity (T‐AOC) and gene expressions of SOD, CAT, GPx. The results showed that during the grower period a diet including 100 mg/kg YSE improved CAT capacity in the ileum, tended to increase activities of GPx in the duodenum, and further showed enhancing tendencies in SOD and GPx abilities in ileum. Gene expressions of CAT, SOD and GPx in the ileum tended to upregulate at 100 mg/kg YSE level. In the finisher period and over the whole period, all YSE groups had a reduced FI compared to the control group without compromising BW; 100 and 200 mg/kg YSE significantly improved FCR. In conclusion, the improved growth performance of broilers during the finisher period may be due to enhanced antioxidative ability in the grower period with YSE supplementation. This study provided evidence of using YSE as an additive to enhance growth in broilers. 相似文献
45.
Ivy Elizabeth Baremore Kate Irene Andrews Loraine Frances Hale 《Fisheries Research》2009,99(3):203-209
Several methods were used in an attempt to develop an age and growth model for the Atlantic angel shark (Squatina dumeril). Band counts from vertebral sections, which were fit to the traditional von Bertalanffy growth equation, the Gompertz growth equation, and the two-parameter von Bertalanffy growth equation, did not produce realistic parameter estimates. Additionally, a length-based Bayesian model was applied to fishery-independent length–frequency data, and a full Bayesian model was fitted to length-at-age data to estimate parameters for von Bertalanffy growth equation. Both the length-based and full Bayesian models failed to converge; the length–frequency data showed high bimodality unrelated to season, year, or other factors, and band counts were not predictable by length. Vertebral band counts were not valid for ageing Atlantic angel sharks, and length-based methods, which require normally distributed length–frequencies, were not appropriate for this data set. This study represents the first attempt at modeling age and growth for this species and provides research guidelines for future research initiatives. 相似文献
46.
Irene Borra-Serrano Tom De Swaef Jonas Aper An Ghesquiere Koen Mertens David Nuyttens Wouter Saeys Ben Somers Jürgen Vangeyte Isabel Roldán-Ruiz Peter Lootens 《Euphytica》2018,214(8):142
Perennial ryegrass (Lolium perenne) is a perennial crop used in temperate regions as forage. In L. perenne breeding programs, persistency is an important trait. Poor persistency results in sward degradation and associated yield and nutritive value losses. Breeders assess persistency of accessions using visual scoring in field plots during the 2nd or 3rd growing season. This evaluation system is easy and cheap but is not free from human bias. In this study, the correlation between the scoring done by different breeders was only 0.243. As an alternative we have developed a methodology to assess persistency of L. perenne breeding materials based on vegetation indices (VIs) derived from Unmanned Aerial Vehicle (UAV) imagery. The VIs Excess green (ExG2), Green Leaf Index and Normalized green intensity (GCC) were found to provide consistent results for flights carried out under different light conditions and were validated by ground reference information. The correlation between the VIs and the percentage of ground cover extracted from on-ground imagery was 0.885. To test the implementation of the method we compared the ExG2 value based approach to selection with a visual score based selection methodology as applied by two breeders. The breeding decisions of Breeder A agreed well with decisions based on ExG2 values (74.6%), but those of Breeder B displayed a lower agreement (54.0%). In contrast, agreement between decisions based on different flights was very high (91.6%). The methodology was validated for general applicability. In summary, the results demonstrate that basing persistency selection in L. perenne breeding programs on ExG2 values from UAV imagery is likely to be more objective in comparison to the currently-used visual scoring method. 相似文献
47.
48.
Dini I Tenore GC Trimarco E Dini A 《Journal of agricultural and food chemistry》2006,54(16):6089-6093
An analysis of the polar extracts from sweet potato Ipomoea batatas (Convolvulaceae) led to the isolation of seven unknown aminoacyl sugars. On the basis of 1D, 2D NMR, and mass spectrometry data, the structures of the compounds were elucidated as: beta-D-fructofuranosyl-(2 --> 1)-alpha-D-[2-O-valyl]-glucopyranoside (1), beta-D-fructofuranosyl-(2 --> 1)-alpha-D-[2-O-tyrosyl]-glucopyranoside (2), beta-D-fructofuranosyl-(2 --> 1)-alpha-D-[2-O-threonyl]-glucopyranoside (3), beta-D-fructofuranosyl-(2 --> 1)-alpha-D-[2-O-hystidyl]-glucopyranoside (4), 2-beta-D-fructofuranosyl-(2 --> 1)-alpha-D-[2-O-alanyl]-glucopyranoside (5), beta-D-fructofuranosyl-(2 --> 1)-alpha-D-[2-O-tryptophanyl]-glucopyranoside (6), and beta-D-fructofuranosyl-(2 --> 1)-alpha-D-[2-O-glycyl]-glucopyranoside (7). 相似文献
49.
Irene Rodrigues Freitas William Renzo Cortez-Vega Carlos Prentice 《Journal Of Aquatic Food Product Technology》2013,22(7):1034-1044
ABSTRACTThis work aimed to evaluate the physicochemical and functional properties of proteins recovered from whitemouth croaker (Micropogonias furnieri) and Argentine anchovy (Engraulis anchoita) residues obtained by the process of acid solubilization using HCl at pH = 2 and alkaline solubilization using NaOH at pH = 12 and isoelectric precipitation (pH = 5.5). The proximate composition and functional properties were determined. The solubilization and water holding capacity (WHC) of the recovered protein were studied in the pH range of 3, 5, 7, 9, and 11. The high protein content and lowest lipid reduction presented by the protein recovered from the whitemouth croaker residue and obtained by the acid solubilizing process was 97.1 and 98.4%, respectively. The maximum solubilized protein was at pH 3 and 11, and the minimum solubilized protein was at pH 5 for both species. The greater ability to retain oil was observed for the alkaline solubilization process (8.3 and 7.3). The lower WHC was at pH 5. The acid and alkali residue concentrates of the whitemouth croaker presented higher WHC at pH 3 and 11. These proteins can be used in preparing edible films and have been used to produce bioactive compounds for supplements or functional ingredients. 相似文献
50.
Irene Dimopoulou Tilemahos L. Anagnostou Nikitas N. Prassinos Ioannis Savvas Michael Patsikas 《Veterinary anaesthesia and analgesia》2017,44(5):1189-1197