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311.
Dual-energy x-ray absorptiometry was used to measure bone mineral density of four regions in healed femora of nine dogs after fracture fixation with a leg-lengthening plate. Six to 85 months (mean, 46 months) after surgery, the bone mineral density of healed femora was not significantly different from the contralateral uninjured femora ( P >.05; power = 0.8 at Δ= 15%). Radio-lucencies around the proximal screws, apparently associated with screw loosening, were seen on radiographic views of the healed femora of three dogs. In one of these dogs, one screw in the proximal metaphysis had broken. Force-plate analysis of gait was also performed on dogs at the time of bone mineral density measurement. Peak vertical force was decreased in the pelvic limb with the healed fracture compared with the contralateral unoperated limb ( P < 0.05). Clinically apparent lameness in three dogs did not appear to be associated with altered bone mineral density and may have been caused by hip osteoarthritis, a nondisplaced hairline diaphyseal fracture, and screw loosening in conjunction with extensive post-traumatic soft tissue injury.  相似文献   
312.
Evaluation of Tissue Adhesive to Contain Axonal Regeneration in Horses   总被引:1,自引:1,他引:0  
Bilateral palmar and plantar digital neurectomies were completed in 10 horses (a total of 80 neurectomies) using one of three methods: (1) simple transection (guillotine method); (2) epineural capping; (3) n-butyl cyanoacrylate injected into the epineural sheath to act as a nerve sealant. Horses were regularly evaluated clinically for tenderness in and around the surgical site, as well as skin sensation at the coronary band in the heel region, during the 12-week course of the study. None of the surgical sites exhibited any signs of drainage or infection. Horses were then euthanatized, the nerve stumps were dissected from surrounding tissues, and the length and width of the tissue mass that had formed on the end of the nerve was recorded. Longitudinal and transverse sections of the nerve endings were examined histologically for numbers of proliferating axon sprouts (neuroma formation); whether the axons had penetrated the epineurium; degree of Schwann cell proliferation; degree of chronic inflammation; extent of foreign body reaction; extent of retrograde degeneration of the nerve bundles; and amount of fibro vascular proliferation. The proportion of legs exhibiting tenderness or heel sensation did not differ significantly between the three different treatments at any of the six different times they were examined. There was no difference between the three treatments in the length or width of the fibrous tissue scar on the ends of the nerves or in the number of sprouting axons from the ends of the nerves. Of 80 nerves examined, only two nerves were not confined to the epineurium. Both these nerves had been treated by simple transection. Statistically there was more chronic inflammation and foreign body reaction in the acrylic treated nerves, but no difference in Schwann cell proliferation or retrograde degeneration between the three treatments. There was slightly less fibrovascular proliferation in the transected nerves than in those subjected to epineural capping or acrylic, but the difference was not statistically significant. The use of the tissue adhesive n-butyl cyanoacrylate to prevent the continuous growth of axons after digital neurectomy seems to offer little advantage over more traditional methods of neurectomy.  相似文献   
313.
Supernatants derived from desiccated plant material gathered from Agrostis/Festuca vegetation had an inhibitory effect on the germination and early development of seedlings of Trifolium repens cv. S184. Two compounds, o -hydroxyphenylpropionic acid and benzoic acid, were identified chromatographically and their structures confirmed by mass spectrometry. Commercial preparations of the two compounds were effective inhibitors at a concentration of 10−2 and 10−3 m respectively when T. repens was used as the phytometer species. Benzoic acid lost its inhibitory effect when the pH of the two solutions was adjusted to pH 5·5. The roots of seedlings of white clover were severely distorted by o -hydroxyphenylpropionic add at 10−3 m . It is likely that phenolic acids, produced from the surface trash created by slot seeding procedures, interfere with the establishment of white clover in upland pastures.  相似文献   
314.
Abstract— A unique dermatosis of male miniature swine is described. The disease occurs in post-pubertal pigs, and is characterized by symmetrical, indurated, plaques over the truncal region. Histologically, the dermis and panniculus are effaced by thick, interwoven bundles of collagen resulting in an absence of deep dermal elastin. Hypertrophy and hyperplasia of superficial dermal vessels, fibroblasts and fibrocytes are accompanied by perivascular infiltrates of lymphocytes, plasma cells and eosinophils. The pathogenesis of this unusual dermatosis, designated as “progressive dermal collagenosis of male miniature swine” is unknown. Résumé— Une dermatose originale du cochon nain mâle est décrite. La maladie apparait chez des cochons post pubertaires, et est caractérisée par des plaques sur le tronc, indurées et symétriques. Histologliquement, le derme et le pannicule sont envahis par d‘épais falsceaux de collagène, entrainant l'absence d’élastine dermique. Les vaisseaux du derme superficiei sont hyperplasiés et hypertrophiés, des fibroblastes et des fibrocytes sont accompagnés d'un infiltrat inflammatoire périvasculaire de lymphocytes, éosinophiles et plasmocytes. La pathogénie de cette affection peu commune, appelée “collagénose dermique progressive du cochon nain mâle” est inconnue. Zusammenfassung— Es wird eine einzigartige Hauterkrankung beim männlichen Miniaturschwein beschrieben. Die Krankheit tritt bei postpubertären Schweinen auf und wird durch symmetrische, indurierte Plagues im Rumpfbereich gekennzeichnet. Histologisch treten Dermis und Pannikulus gegenüber dicken, verflochtenen Kollagenbündeln in den Hintergrund, wodurch das tiefe, dermale Elastin verschwindet. Die Hypertrophie und Hyperplasie der oberflächlichen Hautgefäße, Fibroblasten und Fibrozyten wird von perivaskulären Infiltraten aus Lymphozyten, Plasmazellen und eosinophilen Granulozyten begleitet. Die Pathogenese dieser ungewöhnlichen Dermatose, die als “progressive dermale Kollagenose des männlichen Miniaturschweins” bezeichnet wird, ist unbekannt. Resumen El presente artículo es una descripción de una dermatosis única del macho cerdo miniatura. Le enfermedad aparece después de la pubertad, y se caracteriza por la aparición de placas simétricas sobre la región del tronco. El exámen histológico de la dermis y del tejido panicular revela la presencia de gruesas bandas de colágeno entrelazadas, lo cual tiene como resultado la ausencia de la capa de elastina profunda. La hipertrofia e hiperplasia de los vasos superficiales dérmicos, fibroblastos y fibrocitos, se ve acompañadas de infiltrados perivasculares de linfocitos, células plasmáticas y eosinófilos. La patogénesis de esta rara dermatosis Ilamada ‘colagenosis dérmica progresiva del cardo macho miniatura’, es desconocida.  相似文献   
315.
对6头试验公鹿用假台鹿采精,采精前对特制的假阴道以药用凡士林为滑润剂,注水充气,温度为40℃±1℃,以适宜的压力和滑润度,将其安装在人工制做的假台鹿内。拨赶公鹿于采精场诱其爬跨。结果,试验的6头公鹿中有4头能够采精,共22头次,射精量平均每头次1.54ml,精子密度为18.6—37亿/ml,精子活力在0.8以上。93年每头次生产细管冻精106.25支(425支/4头次),是同年电刺激采精法平均64.4支/头次(902支/14头次)的1.65倍,此法既能采到质量高的精液,又比电采法省工、省时、省力、安全,是一种理想的马鹿采精方法。  相似文献   
316.
This paper describes four cats with hyperadrenocorticism. Cat 1 showed polydipsia and polyphagia. Diabetes mellitus was initially diagnosed. As the animal appeared to be insulin resistant, pituitary and adrenocortical function tests were performed and the diagnosis of hyperadrenocorticism was made. Resistance to the high-dose dexamethasone suppression test was noticed in this cat. Pathological examination revealed a pituitary chromophobe adenoma. Cat 2 presented with diabetes mellitus, which was treated with insulin. The animal had a pendulous abdomen and its coat was in a poor condition. The low-dose dexamethasone suppression test demonstrated hyperadrenocorticism. Necropsy findings of pituitary tumour and hyperplasia of the adrenal cortex confirmed the diagnosis. Cat 3 showed clinical abnormalities indicative of hyperadrenocorticism, for instance, muscle weakness, alopecia, multiple abscesses. The diagnosis of hyperadrenocorticism was confirmed by the results of the lowe-dose dexamethasone suppression test. Pathological examination revealed an adrenocortical carcinoma. Cat 4 presented with polydipsia. The cause of this symptom was not found initially. One and a half years later additional symptoms, such as nephritis and polyphagia developed. Hyperadrenocorticism was diagnosed because of a palpable mass cranial to the left kidney. The diagnosis was confirmed by the results of the lowe-dose dexamethasone suppression test and the necropsy findings.  相似文献   
317.
318.
The major nematode pests of cultivated plants in Greece include root-knot nematodes Meloidogyne spp. (in almost all plants except citrus), cyst-forming nematodes Globodera rostochiensis, G. pallida (in potato), Heterodera avenae (in cereals), Ditylenchus dipsaci (in vegetables and ornamental plants) and Tylenchulus semipenetrans (in citrus). Based on observations made on samples examined at Benaki Phytopathological Institute, it was confirmed that serious infestation of new kiwi orchards with Meloidogyne spp. originated from seedlings infested at the nursery. Also the wide distribution of the nematode Tylenchulus semipenetrans in citrus orchards was mainly attributed to infested seedlings. The above observations led us, in 1985, to the decision to study the nematological fauna of nurseries in Greece.  相似文献   
319.
Seventeen lion heads were examined. Their arteries were injected with colored supervinyl-chloride (dissolved in acetone) after which the heads were macerated biologically. The rete mirabile of the maxillary artery was located extracranially and was formed by numerous arteries that arose from the dorsal and medial surfaces of the maxillary artery. The rete released branches (rami retis) which entered the cranial cavity through the orbital fissure where they anastomosed with the intracranial segment of the internal carotid artery. The extracranial portion of the internal carotid was found to be obliterated. Some other arteries leaving the rete anastomosed with the internal ophthalmic artery before it entered the optic canal. The following further arteries left the rete: A. ethmoidalis externa, A. ophthalmica externa, rami musculares and ramus pterygoideus. The rete mirabile of the maxillary artery in the lion provides the principal source of the blood for the brain; it also supplies the orbit.  相似文献   
320.
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