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21.
Thirty of 52 pedigree Suffolk lambs (58 per cent) were born with arthrogryposis characterised by bilateral flexion rigidity of the metacarpophalangeal and carpal joints. The recent introduction of a breeding ram was identified as the only significant risk factor in the flock, and embryo transfer was used to test the hypothesis that the arthrogryposis was an inherited disorder associated with the introduction of this ram. Two adult ewes that had previously produced lambs with arthrogryposis by the ram and four of its affected daughters were available as donors, and 20 crossbred ewes were used as recipients. Ten Suffolk-crossed ewes that had no known familial relationship with the ram were also mated by the ram as controls and they produced 10 normal lambs. Following embryo transfer, 19 lambs were born, of which seven were stillborn; arthrogryposis was evident in 10 of the 12 live lambs. Analysis of the data suggested that in the population under study, arthrogryposis was inherited as an autosomal recessive condition.  相似文献   
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Treatment options for dogs with nasopharyngeal stenosis include fluoroscopic placement of metallic stents. Reported complications include entrapment of hair and food, obstruction and persistent nasal discharge. Two toy breed dogs were examined for persistent nasal discharge and halitosis at 4 and 20 months after placement of permanent metallic stents for acquired nasopharyngeal stenosis. Full thickness defects were found in the palate of both dogs, with extensive communication between the mouth and the nasal passages. Portions of the metal stent were observed within the lesion in both patients. Additional treatment was declined by the owner of one dog; the stent was removed through the fistula in the other dog. Palatal erosion with secondary oronasal fistulation is a potential complication of nasopharyngeal stent placement in dogs.  相似文献   
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In addition to the direct impact of a farm safety day camp on its participants' knowledge and safety awareness, there are extended and indirect effects that occur through the wider dispersion of information and the involvement and cooperation of community members. Reports completed by 228 coordinators of farm safety day camps, report forms completed by 5,037 volunteers at farm safety day camps, and telephone interviews with 924 parents of farm safety day camp participants were analyzed for evidence of the impact of the camps beyond the immediate knowledge gained by the children who participated. These data indicate that the indirect benefits to a community include enhanced safety awareness within the wider community as children and adult volunteers disseminate the information they learned, as well as enhanced community strength and cohesiveness resulting from the cooperation of many individuals and organizations in achieving a common goal.  相似文献   
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ObjectiveTo investigate the contribution of K+ channels on peripheral antinociception induced by ketamine.Study designProspective experimental study.Animals110 male Wistar rats weighing 160–200 g.MethodsThe paw pressure required to elicit limb flexion was designated as the nociceptive threshold. Hyperalgesia was induced by intraplantar injection of prostaglandin E2. All drugs were administered locally into the right hind paw of rats. Ketamine was administered into the right hind paw 2 hours and 55 minutes after local injection of PGE2. Tetraethylammonium was administered 30 minutes prior to ketamine and the other K+ channel blockers, glibenclamide, dequalinium and paxilline, were administered 5 minutes prior to ketamine.ResultsProstaglandin E2 (2 μg per paw) induced hyperalgesia. Ketamine (10, 20, 40 and 80 μg per paw) elicited a local peripheral antinociceptive effect that was antagonized by a specific blocker of ATP‐sensitive K+ channels, glibenclamide (20, 40 and 80 μg per paw). In another experiment, the non‐selective voltage‐dependent K+ channel blocker tetraethylammonium (30 μg per paw) and small and large conductance blockers of Ca2+‐activated K+ channels, dequalinium (50 μg per paw) and paxilline (20 μg per paw), were ineffective at blocking the effect of a local ketamine injection.Conclusions and clinical relevanceAnalysis of these results provides evidence that ketamine, may in part, induce peripheral antinociceptive effects by ATP‐sensitive K+ channel pathway activation.  相似文献   
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Increasing salinity of soil and water threatens agriculture in arid and semiarid regions. By itself, the traditional engineering approach to the problem is no longer adequate. Genetic science offers the possibility of developing salt-tolerant crops, which, in conjunction with environmental manipulation, could improve agricultural production in saline regions and extend agriculture to previously unsuited regions.  相似文献   
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Lysergic acid diethylamide: radioimmunoassay   总被引:3,自引:0,他引:3  
A radioimmnunoassay for d-lysergic acid diethylamide (LSD) is described. Antibodies to LSD were obtained by immunizing rabbits with a conjugate of LSD and human serum albumin. The specificity of the antibody was shown by competitive binding studies. The method has been used to detect the presence of LSD in human urines. Picogram amounts can be measured by this assay.  相似文献   
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Abstract

CASE HISTORY: A group of 545 pregnant rising 2-year-old Coopdale ewes on a Southland sheep farm were grazed over winter on a fodder beet (Beta vulgaris) crop. Subsequently, 45 out of approximately 750 lambs were born with a variety of skeletal deformities, including shortened limbs, varus and valgus angular limb deformities, palmar grade stance and cranial bowing of the carpus. Analysis of the crop showed the fodder beet contained a low percentage of phosphorus. In addition, 60 out of 460 rising 2-year-old ewes that had been grazed on the fodder beet crop as 1-year-olds had incisor abnormalities and malocclusion.

PATHOLOGICAL FINDINGS: Two affected lambs (1-day-old and 3-days-old) with representative clinical signs examined postmortem were found to have markedly enlarged costochondral junctions, and noticeably enlarged long bone metaphyses. In addition, one lamb had a dense band of metaphyseal sclerosis beneath the physes of all long bones examined. Histopathological findings included small islands and columns of chondrocytes and eosinophilic cartilage matrix present in the metaphysis. Metaphyseal trabeculae were disorganised and often lined by accumulations of pale pink osteoid; similar pale pink osteoid was also present in the cortices. Unerupted molar teeth in the affected lambs lacked a layer of enamel, and the dentine was irregular with globular basophilia.

DIAGNOSIS: The gross and histopathological lesions were consistent with a diagnosis of rickets.

CLINICAL RELEVANCE: Nutritional congenital rickets has not been previously diagnosed in sheep, but is a recognised disease of human infants with vitamin D deficient mothers. The rickets in affected lambs was most likely associated with phosphorus deficiency as a result of the pregnant ewes grazing fodder beet during gestation. While vitamin D deficiency was not definitively ruled out in these cases, practitioners are alerted to the possible effects of feeding phosphorus-deficient fodder beet to ewes for long periods during gestation and to 1-year-old sheep during important growth periods.  相似文献   
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