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41.
Abstract The mineral analyses of nails from 32 normal dogs were determined by atomic absorption spectrophotometry or colorimetrically. Data were compared with the mineral analyses of nails from 21 cases of idiopathic canine onychomadesis. German Shepherd dogs were significantly over represented (P < 0.005) in the affected group compared with a reference hospital population. Significant increases in the concentration of calcium (P < 0.05), potassium (P < 0.05), sodium (P < 0.0005) and phosphorus (P < 0.05) were found in nails from affected dogs compared with nails from normal animals. The mineral composition of nails from affected German Shepherd dogs was significantly different from that of affected non-German Shepherd dogs. Normal ranges for the mineral concentrations of normal canine nail are presented for the first time. The different composition of nails from affected German Shepherd dogs compared with nails from other breeds suggests a different aetiology to the onychomadesis, although the cause of the problem remains speculative. Résumé— Des analyses d'ongles de 32 chiens sains ont été déterminées par spectrophotométrie d'absorption atomique ou colométrie. Celles-ci ont été comparées avec celles d'ongles de 21 chiens à onychomadèse idiopathique. Les Bergers allemands sont surreprésentés (P < 0,005) dans le groupe de chiens malades, comparativement à la population de référence. Des augmentations significatives de la concentration de calcium (P < 0,05), de potassium (P < 0,05), de sodium (P < 0,005) et de phosphore (P < 0,05) sont notées dans les ongles des Bergers allemands à onychomadèse idiopathique, par rapport à celles des ongles des chiens atteints, mais non de race Berger allemand. Des valeurs usuelles des concentrations minérales des ongles du chien sont présentées pour la première fois. La composition différente des ongles des Bergers allemands affectés comparéeà celle des ongles des autres races affectées suggère une étiologie différente de l'onychomadèse dans cette race, bien que la cause reste encore imprècise. [Harvey, R. G., Markwell, P. J. The mineral composition of nails in normal dogs and comparison with shed nails in canine idiopathic onychomadesis (Composition minérale des ongles de chiens sains et comparaison avec celle des ongles provenant de chiens à onychomadèse idiopathique). Veterinary Dermatology 1996; 7 : 29–34.] Resumen El análisis mineral de las uñas de 32 perros normales se determinó por espectrofotometría atómica de absorción o colorimétricamente. La información se comparó con los análisis de 21 casos de onicomadesis idiopática canina. Los perros Pastor Aleman estaban significativamente sobrerepresentados (P < 0.005) en el grupo afectado comparado con la población de un hospital de referencia. Se encontraron aumentos significativos en la concentración de calcio (P < 0.05), potasio (P < 0.00005) y fósforo (P < 0.05) en la población afectada, comparado con uñas de animales normales. La composicón mineral de uñas de perros Pastor Alemán afectados fue significativamente distinta de la de los perros no Pastor Alemán afectados. Se presenta por primera vez los valores de las concentración mineral de las uñas normales en el perro. La composición distinta de las uñas de perros Pastor Alemán afectados comparadda con uñas de otras razas sugiere una etiología distinta de la onicomadesis, aunque la causa del problema continúa siendo motivo de especulación. [Harvey, R. G., Markwell, P. J. The mineral composition of nails in normal dogs and comparison with shed nails in canine idiopathic onychomadesis (Composición mineral de las uñas de perros normales comparada con la uñas eliminadas en la onicomadesis idiopática canina). Veterinary Dermatology 1996; 7 : 29–34.] Zusammenfassung— Die Mineralstoffanalyse der Krallen von 32 gesunden Hunden wurde mit Atomabsorptionsspektrometrie oder Kolorimetrie durchgeführt. Die Daten wurden mit Mineralstoffanalysen von Krallen aus 21 Fällen von idiopathischer kaniner Onychomadesis verglichen. Deutsche Schäferhunde waren signifikant überrepräsentiert (P < 0,005) in der betroffenen Gruppen im Vergleich zur einer Referenzpopulation der Klinik. Signifikante Anstiege in der Konzentration von Kalzium (P < 0,05), Kalium (P < 0,05), Natrium (P < 0,0005) und Phosphor (P < 0,05) wurden in den Krallen der betroffener Hunde im Vergleich zu denen gesunder gefunden. Die Mineralstoffzusammensetzung der Krallen betroffener Deutscher Schäferhunde unterschied sich signifikant von der betroffener Hunde anderer Rassen. Referenzbereiche für die Mineralstoffkonzentrationen gesunder Hundekrallen werden erstmalig vorgestellt. Die verschiedene Zusammensetzung der Krallen betroffener Deutscher Schäferhunde im Vergleich zu den Krallen anderer Rassen legt eine unterschiedliche Ätiologie der Onychomadesis nahe, obwohl die Ursache der Störung spekulativ bleibt. [Harvey, R. G., Markwell, P. J. The mineral composition of nails in normal dogs and comparison with shed nails in canine idiopathic onychomadesis (Die Mineralstoffzusammensetzung der krallen gesunder Hunde im Verleich zu abgesto ßenen Krallen bei kaniner idiopathischer Onychomadesis). Veterinary Dermatology 1996; 7 : 29–34.]  相似文献   
42.
ABSTRACT Local and regional employment growth is generally studied either by searching for local qualitative explanatory factors such as governance, synergy between firms, and milieu effects, or by searching for general growth factors using statistical techniques. The body of work that relies on this approach has tended, in keeping with economics’ nomothetic tradition, to assume that local and regional growth factors are constant over space. The focus of this paper is on exploring the spatial stationarity of employment growth factors in Canada, but it also seeks to clarify some of the broad principles behind spatial regression techniques in order to provide a point of entry and a conceptual framework for empirical researchers. To do so, we apply a recently developed technique, Geographically Weighted Regression (GWR), and we explore the method's advantages and limits for answering our research question. We find evidence that growth factors differ across Canada, but we also conclude that the GWR technique, given the number and shape of regions available for our analysis and given certain limitations that are currently inherent to the method, can only provide tentative and exploratory results.  相似文献   
43.
A 5-year-old, male German shepherd dog was evaluated for a 5-week history of vomiting, diarrhea, lethargy, and weight loss. In abdominal radiographs, there was an unusual corrugated appearance within a loop of intestine. Sonographically, this loop also had a similar corrugated appearance with alternating hyperechoic and hypoechoic bands. Lymph nodes within the abdomen and thorax were enlarged, and a thoracic mass was also detected. Ultrasound-guided fine-needle aspirates of the mesenteric lymph nodes were highly suggestive of lymphoma. After postmortem examination, a diagnosis of multicentric lymphoma with involvement of the gastrointestinal tract was made.  相似文献   
44.
Research conducted in El Salvador, Central America, demonstrated that an interval of 3 days between application of glyphosate and tillage was sufficient to cause 90% reduction in purple nutsedge (Cyperus rotundus L.) plants, while delays of 11–23 days generally gave slightly less reduction. à second application to the same plots 35 days following tillage resulted in more than 90% reduction with all intervals. Approximately 3 months after the initial treatment, tuber numbers had been reduced to half the original population. Germination of the remaining tubers was reduced by more than 50%. Glyphosate applied during the dry season caused an average of 79% reduction in plant numbers compared with 88% in the rainy season. However, in the dry season, the remaining plants had no competition from other weeds and after 5 months there was only à 40% reduction in nutsedge population. During the rainy season, 1, 2 and 3 kg/ha were equally effective, but 1 kg/ha was not sufficient in the dry season.  相似文献   
45.
Eleven cases of congenital ocular defects were found in the screening of 144 Cavalier King Charles Spaniels in Sweden. Mainly posterior lenticonus, cataracts and microphthalmia were observed in the affected dogs, most of which were interrelated. Pathology was obtained from one of the cases demonstrating bilateral posterior lens capsule rupture with an unusual cellular reaction of the exposed lens material.  相似文献   
46.
The Effects of Fixation of the Ulna to the Radius in Young Foals   总被引:1,自引:0,他引:1  
The effects of radioulnar fixation were studied in 21 Quarter horse foals by applying a bone plate to the caudal aspect of the proximal part of the ulna, with screws engaging both the radius and the ulna. The plates were applied at 1 month of age in six foals (group I), 5 months of age in six foals (group II), and 7 months of age in three foals (group III). Six foals underwent sham operations at 1 month of age to serve as controls (group IV). Ulnar dysplasia and elbow subluxation developed in all treated foals. The magnitude of ulnar dysplasia was inversely related to the patient's age at fixation and was accompanied by degenerative joint disease and lameness in foals undergoing fixation at 1 and 5 months of age. Removal of the fixation appliances 16 weeks after implantation in three foals from each of groups I and II failed to reverse the degree of ulnar dysplasia. Although foals undergoing fixation at 7 months of age (group III) were not lame, radiographic evidence of subluxation and subtle degenerative changes in the articular cartilage of the treated elbow did develop. Recommendations for avoidance of radioulnar fixation were developed from these observations.  相似文献   
47.
48.
A cat was presented in coma following severe trauma. The cat was alert and walking within 24 hours, after treatment with intravenous dexamethasone and mannitol. However, he subsequently began to show evidence of severe abdominal pain. An exploratory laparotomy revealed traumatic avulsion of the left limb of the pancreas. A sub-total pancreatectomy was performed and the cat recovered well. Two weeks post-operatively, the cat was re-presented with ataxia, proprioceptive deficits, and upper motor neuron weakness in all four limbs. Radiographs revealed a fracture/luxation of C1–C2 which could not be adequately stabilized solely via a dorsal approach. A combined ventral and dorsal approach produced stabilization of the cervical spine which was clinically successful. Two months post-operatively there was stability but malalignment of C1–C2, and the cat appeared normal.  相似文献   
49.
50.
Two 2-year-old Salers cattle from different herds raised on pasture were evaluated for retarded growth and diarrhea. Increase of liver enzyme activities and prolonged sulfobromophothalein (BSP) half life (T1/2) indicated liver disease with impaired liver function. Histopathologic examination of liver biopsies revealed a micronodular cirrhosis with marked deposition of hemosiderin in hepatocytes, Kupffer cells, and arterioles. Transferrin saturation (TS) and liver iron content were markedly increased, consistent with a diagnosis of hemochromatosis. Both animals were euthanatized due to deterioration in their condition. Necropsy findings included hepatomegaly and hemosiderin accumulation in the liver, lymph nodes, pancreas, spleen, thyroid, kidney, brain and other glandular tissue. Continued surveillance of the second herd (serum iron, total iron binding capacity [TIBC], unsaturated iron binding capacity [UIBC], and TS), identified a heifer as a hemochromatosis suspect in a subsequent generation. Liver biopsies from that animal revealed the same histopathologic changes as the previous 2 animals, and similar increases in liver iron content (8,700 ppm, normal range 45 to 300 ppm). The 3 affected cattle were all products of line breeding programs and shared a common ancestor. The absence of dietary iron loading in conjunction with the histopathologic and metabolic findings were consistent with a diagnosis of primary hemochromatosis. The reported disease is similar to idiopathic hemochromatosis in human beings in which there is a hereditary defect in iron metabolism.  相似文献   
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