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81.
M J Champagne R Higgins J M Fairbrother D Dubreuil 《Canadian journal of veterinary research》1991,55(3):239-245
A biotin/avidin double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) for the detection of antigens of Leptospira interrogans serovars in experimentally inoculated bovine urine samples was evaluated. Immunoglobulin G (IgG) from rabbits immunized with L. interrogans serovar hardjo type hardjobovis sonicated, whole cell, and formalinized-heated antigen preparations were purified by a protein A-superose column coupled to fast protein liquid chromatography, and evaluated for species specificity in the ELISA. The ELISA using each specific IgG detected as few as 10(4) leptospires of the homologous serovar hardjo diluted in phosphate-buffered saline solution with Tween 20 (PBSS-Tween 20). On immunoblot analysis of proteinase-K-digested whole cell leptospiral preparations, each IgG revealed the presence of bands specific to serovar hardjo, suggesting the presence of serovar-specific epitopes on the lipopolysaccharide molecules. The minimum number of cells of heterologous serovars pomona, grippotyphosa, bratislava, icterohaemorrhagiae and copenhageni detected by each ELISA was greater, ranging from 10(6) to 10(7). The common antigenic determinants observed on immunoblot analysis were different for each specific IgG, except for a major cross-reacting, possibly flagellar, protein doublet at approximately 36-36.5 kDa. Leptospires were equally well detected by the ELISA in both bovine urine and PBSS-Tween 20. 相似文献
82.
Allyson C. Berent DVM Jeffrey Todd DVM Jennifer Sergeeff DVM DACVIM Lisa L. Powell DVM DACVECC 《Journal of Veterinary Emergency and Critical Care》2005,15(2):128-135
Objective: To describe diagnostics, therapy, and sequelae of acute carbon monoxide (CO) toxicity because of a motor vehicle generator in 4 dogs and 2 cats. Series summary: Four dogs and 2 cats presented for recumbency, disorientation, dyspnea, and stiffness after an estimated 6–8 hour exposure to exhaust from a generator. Diagnostics included a serum carboxyhemoglobin levels evaluation, arterial blood gas analysis, pulse oximetry readings, and blood pressure measurements. Initial therapy included oxygen (O2) administration, intravenous bronchodilators, fluids, and a hemoglobin‐based O2 carrying (HBOC) molecule. Following administration of the HBOC, 4 of the 6 animals showed dramatic clinical improvement. Two weeks after hospital discharge, the owner reported potential hearing deficits in all animals. Brain auditory evoked response (BAER) tests were conducted in all surviving animals and some degree of hearing impairment was documented in all cases, with complete clinical resolution noted 6 weeks later. Unique information provided: This report describes the therapeutic use of an HBOC in acute isolated CO toxicity (i.e. without the complications of smoke inhalation). In addition, delayed nervous system dysfunction was documented in all surviving animals. 相似文献
83.
A H Hussein E Cornaglia M S Saber Y el-Azhary 《Canadian journal of veterinary research》1995,59(3):235-237
Fecal samples from diarrheic and nondiarrheic dairy calves (1 to 3 weeks old) from 12 regions of Quebec, collected between 1992 and 1994, were screened for group A bovine rotavirus (BRV) using a combination of 2 VP6-specific monoclonal antibodies (MAbs) in an enzyme-linked immunosorbent assay (ELISA). The overall prevalence of BRV infection was 26.4% (107/405). In diarrheic calves, BRV infection reached 74.3% (55/74), but only 15.7% (52/331) in nondiarrheic calves. BRV-positive samples were serotyped by enzyme-linked immunosorbent assay (ELISA) using G6 and G10 specific MAbs. The analysis of 107 field samples revealed that, in diarrheic calves, 34.5% (19/55) were G6, 27.2% (15/55) were G10, 9% (5/55) were G6 and G10 positive, and 29.9% (16/55) were G6 and G10 negative. In nondiarrheic calves, 19.2% (10/52) were G6, 19.2% (10/52) were G10, 7.6% (4/52) were G6 and G10 positive, and 53.6% (28/52) were G6 and G10 negative. Rotavirus dsRNA was extracted from BRV-positive samples and examined by polyacrilamide gel electrophoresis (PAGE). Of 107 samples tested, 74 (69.1%) were positive, and all the samples demonstrated a typical group A rotavirus migration pattern. 相似文献
84.
农村金融改革成败的关键在于能否找准农村金融创新的着力点.回顾了近几年农村金融创新取得的成效,分析了存在问题,提出了当前农村金融改革创新应当把握的五大着力点. 相似文献
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88.
浅谈城市园林绿化的生态功能和社会功能 总被引:1,自引:0,他引:1
城市是人类社会活动的主要空间,随着城市化进程的加快,环境问题愈来愈受到关注和重视,园林绿化在城市生态环境的改善中发挥着重要的作用.城市园林绿化既有生态功能又有社会功能. 相似文献
89.
Evaluation of oral, subcutaneous, and nasal administration of Salmonella enteritidis-immune lymphokines on the potentiation of a protective heterophilic inflammatory response to Salmonella enteritidis in day-old chickens.
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M H Kogut K Genovese R B Moyes L H Stanker 《Canadian journal of veterinary research》1998,62(1):27-32
We have previously reported that the prophylactic administration of factor(s) from T-cell supernatants derived from Salmonella enteritidis-immune chickens (ILK) have a favorable effect in controlling or eliminating salmonellosis in neonatal poultry. Experimentally, we have used the intraperitoneal injection as the standard method of administering ILK to neonatal poultry. However, this method is neither easy, practical, nor economical for the poultry industry. In the present study, we evaluated the effectiveness of oral (p.o.), intranasal (i.n.), and subcutaneous (s.c.) administration of ILK for ease of delivery, induction of protective resistance against Salmonella enteritidis (Se) organ invasion, and the ability to activate peripheral blood heterophils in day-old chickens. In the first experiments, delivery of ILK p.o., i.n., and s.c. significantly (P < 0.01) increased the resistance of day-old chickens to Se organ invasion. The level of protection was equivalent to that induced by the i.p. route. Administration of a comparable protein control (bovine serum albumin, BSA) by the 3 routes induced no protective effect against Se organ invasion. Likewise, a significant increase was found in the number of circulating heterophils within 4 h of administration of the ILK by all routes. In the 2nd experiment, the function of the heterophils from ILK-treated birds was compared with that of the control cells in adherence, chemotaxis, and phagocytosis assays. The heterophils from birds given ILK i.p., s.c., p.o., or i.n. had significantly (P < 0.01) increased functional activities when compared to the activities of the heterophils from the control birds. These studies indicate that the delivery of ILK either orally or parenterally, routes which can be used by the poultry industry, can confer protection to chickens against a localized enteric Se organ invasion by potentiating the systemic heterophilic innate response. 相似文献
90.
Lettuce is a cool season crop susceptible to physiological disorders when exposed to supra optimal temperatures. Genotype (G) by environment (E) interaction (GE) of rib discolouration, tipburn, premature bolting and ribbiness in crisphead lettuce was characterized under high temperature and long day growing conditions. Replicated data of 10 crisphead lettuce varieties from two plantings in each of four growing seasons at two locations in Quebec were analysed using the GGE biplot method. Head-weight-over-stem-length ratio, ribbiness, rib discolouration incidence and tipburn incidence were affected (P = 0.00001) by E, G and GE. E explained more variation in head-weight-over-stem-length ratio (77.1%) and rib discolouration incidence (77.3%) than G and GE, whereas GE explained more variation (72.4%) in tipburn incidence and G explained more variation (38%) in ribbiness. Strong crossover GE was detected with rib discolouration and tipburn incidence, but not with head-weight-over-stem-length ratio and ribbiness. Under heat stress, varieties of the Vanguard group had lower ribbiness than those of the Great Lakes group. Cultivar 'Estival' showed consistent resistance to bolting, ribbiness, tipburn and rib discolouration across all E. 相似文献