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31.
Vaccination of pigs against the helminth nematode Trichinella could be a good alternative to prevent the risk of human infection. In order to develop an efficient and safe vaccine, the choice of the adjuvant is an important issue. In this study, two adjuvants were selected to prepare vaccines based on total soluble Trichinella spiralis muscle larvae (ML) antigen: Montanide ISA 70 water in oil emulsion and Montanide IMS nanoparticles. Aluminium hydroxide was used as a reference adjuvant. The immune response was checked by ELISA of parasite antigen specific IgG1 and IgE. Finally, protection induced in vaccinated mice was measured after a T. spiralis challenge by counting ML burdens. The results clearly showed an impact of adjuvants on the specific IgG1 and IgE antibody responses against T. spiralis. Differences were observed between the rates of protection induced according to the type of formulation, although the three adjuvants tested were able to enhance the humoral immune response. This work demonstrated the need to use an adjuvant to obtain a specific IgG1 and IgE responses directed against the total soluble extract of T. spiralis.  相似文献   
32.
Coxo-femoral dislocation was diagnosed in 40 dairy cows. Of the 40 cases, 19 were in a cranio-dorsal direction, 2 caudo-dorsal, 17 caudo-ventral (into the obturator foramen), and 2 cranio-ventral. Thirty cases (75%) were successfully treated by closed reduction. Most cows were treated within 12 h of the dislocation occurring. Treatment was less successful in cases of caudo-ventral dislocation and unsuccessful cases predominated among cows with concurrent obstetrical paralysis or milk fever, and very heavy Friesians.  相似文献   
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Nutrient concentrations and D.R.I.S. indices of leaves, soil chemistry and dendrochronological changes of elemental concentrations in sugar maple (Acer saccharum Marsh.) were used to determine its nutritional status on three sites of contrasting levels of decline. We hypothesized that the ratio of Al to base cations in tree rings would increase more at the most severely declining site, and that the ratios of K+ to divalent cations (Ca2+ and Mg2+) would increase slower or decrease more rapidly over time than at the less severely declining sites. Forest health, based on percentage of foliage missing, and leaf K and Mg concentrations of the three sites were ranked as follows: Morgan Arboretum > Saint-Hippolyte > Entrelacs. Soil pH, Ca, Mg, E.C.E.C. and percentage of base saturation were highest at the Morgan Arboretum, and exchangeable Al in the organic horizon was highest at Entrelacs. Concentrations of K, Ca, Mg and Al, and ratios of these elements in wood were determined for each of the following periods: 1940–1956, 1957–1973 and 1974–1989. Variations in tree ring chemistry among sites were significant for K and Al and all elemental ratios except K:Mg. Al concentration and the ratios of Al to base cations in wood were all significantly higher at Entrelacs (7.0 vs 2.6 and 2.8 mg Al kg?1 for the other two sites, respectively). Weak relationships were generally observed between leaf and soil elemental concentrations, and wood elemental concentrations. The D.R.I.S. K index and soil exchangeable K and Al showed good concordance with wood concentrations. With the exception of Mg, Al and Al:Mg, the effect of period was significant for all other elements and ratios of elements. The most severely declining stand (Entrelacs) differed from the healthiest stand by decreasing K:Ca and increasing A1:K from the 1940–1956 to the 1957–1973 period.  相似文献   
36.
Turbiditic and pelagic sedimentary rocks from the Isua supracrustal belt in west Greenland [more than 3700 million years ago (Ma)] contain reduced carbon that is likely biogenic. The carbon is present as 2- to 5-micrometer graphite globules and has an isotopic composition of delta13C that is about -19 per mil (Pee Dee belemnite standard). These data and the mode of occurrence indicate that the reduced carbon represents biogenic detritus, which was perhaps derived from planktonic organisms.  相似文献   
37.
Stachys arvensis (staggerweed) is a common, widely distributed weed of cultivated and waste land with the potential to intoxicate sheep. Two naturally occurring outbreaks of suspected staggerweed toxicity in the lower North Island were investigated. Affected lambs had been recently moved onto staggerweed-contaminated Brassica spp. crops. In total, 150/1,200 (13%) lambs developed hindlimb paresis, a fine generalised muscular tremor, and hunched posture. When forced to move, many became recumbent. Most lambs recovered within 48 h of removal from staggerweed, although a few developed clinical signs again when transported 2–3 weeks later. Grossly, affected lambs had large amounts of staggerweed plant material and seeds within the rumen. Histopathology showed mild, multifocal degeneration of the white matter tracts of the central nervous system (CNS), most commonly in the ventral funiculi of the spinal cord, and acute, mild to moderate, multifocal degeneration of skeletal muscles. Creatine kinase (CK) activity in serum was mildly to markedly elevated in affected lambs. In a feeding trial, ten 10-month-old Romney lambs were randomly assigned to equal treatment and control groups. Treated lambs were drenched with a liquid extract of staggerweed once daily for 7 days. Three of five treated lambs developed mild exercise intolerance, and 1/5 displayed mild paresis of the hindlimbs, slightly crouched hindlimb stance, and shortened gait, on days 6 and 7. Histologically, 4/5 treated lambs had degeneration in white matter tracts of the CNS, indistinguishable from those seen in the lambs in the outbreak, and in 1/5 lambs there was scattered regeneration of skeletal muscle. CK activity in serum in treated lambs was not significantly higher than that in control lambs. None of the control lambs developed significant clinical signs, histological changes or increases in CK activity in serum. The clinical signs and lesions observed in both the outbreaks and feeding trial were similar to those previously described in studies in Australia, with the exception that myodegeneration was more prominent in the outbreaks in New Zealand. Further characterisation of the pathogenesis of staggerweed toxicity and its potential role as a food safety hazard will be facilitated through identification of the toxic principle(s).  相似文献   
38.
The groundcover levels after corn ( Zea mays L.) silage harvest are rarely adequate to prevent soil erosion, but most corn-growers do not plant cover crops due to time and cost limitations. Herbicide-resistant corn hybrids provide opportunities to control weeds and to utilize cover crops in previously unexplored combinations. Field studies were conducted in 1999 and 2000 at Dryden and Valatie, New York, USA, to determine the potential for managing existing quackgrass ( Elytrigia repens [L.] Nevski) as a cover crop in herbicide-resistant silage corn. Three isolines of the corn hybrid, DKC493, were treated with glyphosate, glufosinate, primisulfuron, nicosulfuron or sethoxydim. Averaged over all site–years, the corn silage yields with glufosinate were similar to those with glyphosate. Glufosinate also resulted in a quackgrass ground cover greater than the 30% threshold for preventing soil erosion. Quackgrass could be managed as a perennial cover crop in silage corn–perennial forage dairy rotations in north-eastern USA.  相似文献   
39.
OBJECTIVE: To determine whether inflammation of the jejunum of horses decreases the number of motilin receptors and amounts of motilin receptor mRNA and alters erythromycin lactobionate binding affinity to the motilin receptor in jejunal tissues. SAMPLE POPULATION: Jejunal segments in 6 adult horses. PROCEDURE: Each horse was anesthetized, and a ventral median celiotomy was performed; 2 segments of jejunum underwent a sham operation, 2 segments underwent ischemic strangulation obstruction (ISO), and 2 segments underwent intraluminal distension (ILD). Treatments were maintained for 120 minutes. From each segment, full-thickness biopsy samples were collected and smooth-muscle homogenates were prepared. Affinity and distribution of motilin binding to these preparations were determined by use of iodine 125 (125I)-labeled synthetic porcine motilin. Via displacement experiments, competition between 125I-labeled motilin and erythromycin lactobionate for binding to motilin receptors in the different segments was investigated. A quantitative real-time PCR technique was used to assess motilin receptor mRNA content in the muscle preparations. RESULTS: Compared with the ISO or ILD segments, the number of motilin receptors was significantly higher in the sham-operated segments; ILD segments contained the lowest number of motilin receptors. The expression of motilin receptor mRNA was significantly decreased in ILD segments but not in ISO segments. Erythromycin lactobionate displacement of 125I-labeled motilin from motilin receptors did not differ significantly among the jejunal segments. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that downregulation and decreased production of motilin receptors in inflamed jejunal tissue contribute to the altered prokinetic response to erythromycin in horses with gastrointestinal disease.  相似文献   
40.
A study of the computer stored records of 293 dairy cows and 652 calvings reveals the effects of retained placenta and metritis complex on reproductive performance. The overall incidence rate of retained placenta was 11.2%. Retained placenta was 4.6 times more likely to occur following twin births than following single births. Most cases of retained placenta occurred during the fall. Forty-five percent of that seasonal increase was explained by an increased number of calvings. Metritis complex was diagnosed following 54.8% of retained placenta cases. Retained placenta alone did not significantly impair reproductive performance. Metritis complex, in the presence or absence of retained placenta, caused a significant (P相似文献   
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