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91.
Light and electron microscopy of keratinization in the laminar epidermis of the equine hoof with reference to laminitis 总被引:1,自引:0,他引:1
The laminar epidermis (epidermis parietis) of hooves from 14 clinically normal horses, 6 months to 15 years old, was examined by light and electron microscopy and immunofluorescence to measure the contributions of this region to the formation of the hoof wall. By their progressive keratinization to form primary epidermal laminae, the secondary epidermal laminae ultimately contributed about 20% of the thickness of the hoof wall (as revealed in the white line [zona alba]). The keratinized, primary epidermal laminae were developed to a height of 4 mm during their proximodistal-course, much of this obscured because of their basal portion being embedded in the cap horn epidermis. From evaluation of structural changes accompanying keratinogenesis in the cell and determination of the contribution of the laminar epidermis to the formation of laminar horn, cap horn, connecting horn, terminal horn, and the white line, we concluded that the sterile bed concept of a nongerminative role for the secondary epidermal laminae is no longer tenable. 相似文献
92.
A survey of the potential use of synthetic oligopeptides in the field of virology is given. The potential value of synthetic peptides as vaccines and diagnostic antigens is discussed. The advantages compared to conventional vaccines as well as the limitations, e.g. the poor efficiency of immune response, are described. 相似文献
93.
O Markusfeld 《Journal of the American Veterinary Medical Association》1989,195(8):1123-1124
Clinical manifestations of anasarca, left displacement of the abomasum, abortion, and incoordination appeared in a group of heifers fed a vitamin A-deficient diet. Older heifers and heifers late in pregnancy were more affected. All clinical signs of disease disappeared within 14 days after vitamin A treatment was begun, and the diet was changed. Although vitamin A deficiency in dairy cows has been documented, this report differs from others in the main clinical manifestations of disease. 相似文献
94.
O el Sawi Mohamed M H Tag el Din S M el Sanousi 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1989,42(2):169-172
Clostridium chauvoei CH3 and Kad1 strains were found to cause marked changes in the blood parameters during the course of blackleg disease. These changes displayed by CH3 were found to be more marked than the local Kad1 strain. Results of changes in the haematological values in calves infected with blackleg organisms, showed an increase in RBC, PCV, Hb and the total leukocyte count. MCHC and MCH remained within normal range values, however, a terminal significant increase of MCV was obtained. Thrombocytes showed a steady drop after infection to the time of death of the animals. 相似文献
95.
Gastrointestinal nematode infections of goats in a sub-tropical and humid zone of India 总被引:1,自引:0,他引:1
Twelve hundred and twenty-eight goats (Capra hircus L.) from a sub-tropical and humid zone of India were examined for gastrointestinal nematodes. The species encountered in the region were: Haemonchus contortus, Bunostomum trigonocephalum, Oesophagostomum columbianum, Trichuris globulosa, O. aspersum, and T. ovis. The overall infection rate was 86.8%. Among various species found, H. contortus emerged as the most prevalent, although B. trigonocephalum and O. columbianum were also significantly in evidence. The seasonal fluctuation in infection was assessed by monitoring the faecal egg count of 1638 goats slaughtered during the 1-year period. The maximum values for the prevalence and overall mean eggs g-1 of faeces (EPG) were observed after the heavy rainfall season and remained at a relatively high level from July to December. H. contortus and O. columbianum appear to be of major importance as parasites in the goats of this climatic zone; the role of climatic factors in their prevalence is discussed. 相似文献
96.
97.
98.
The state of mucus synthesis in the goblet cells of the small intestine was studied in conventional piglets infected with a dose of 200,000 oocytes of the coccidium Isospora suis the first and fifth day after parturition. The synthesis of mucus and its chemical characteristics undergo significant changes during the third and fourth day after infection. The activity of acid and neutral mucous substances declines; their level and the physiological synthetic function of goblet cells begin to return to the normal during the period starting on the eight to tenth day after infection. However, there were no fully functioning goblet cells in the broken numerical ratio even at the end of the period of investigation, i.e. the 13th day after infection. The thin surface layer of mucus remained almost unchanged within the whole extent of the small intestine parts studied. 相似文献
99.
A 3‐year‐old Burmese cat was presented with a history of nonresolving crusted and papular lesions of the face and prior treatment with prednisolone. Skin biopsies revealed typical pox lesions with hyperplasia and ulceration of the epidermis and eosinophilic cytoplasmic inclusion bodies in the epidermal cells. In the upper dermis there was prominent diffuse mast cell infiltration and mild neutrophilic and eosinophilic inflammation. Rare cytoplasmic inclusion bodies were also present in swollen endothelial cells of dermal venules, which showed no other degenerative changes. Histological diagnosis was confirmed by electron microscopic evidence of pox virus particles in inclusion bodies of epidermal cells. The lesions resolved within 6 weeks with systemic antibiotic therapy and supportive care. A 2‐year‐old domestic short‐haired cat was presented with multiple disseminated papular and ulcerative pox lesions with central eschar over the entire body. Histologically, large epidermal inclusion bodies (up to 6 μm in diameter) were present. Widespread haemorrhage and vascular wall necrosis was visible in the dermis and subcutis. Some subcutaneous vessels showed neutrophilic vasculitis. In addition to diffuse dermal neutrophilic and eosinophilic inflammation, a lymphohistiocytic panniculitis was also present. The cat died as a result of massive haemorrhage and lymphedema, despite supportive care. Funding: Self‐funded. 相似文献
100.
V J van Ginneken J F Nouws J L Grondel F Driessens M Degen 《The Veterinary quarterly》1991,13(2):88-96
The influence of temperature (10 degrees C and 20 degrees C) on pharmacokinetics and metabolism of sulphadimidine (SDM) in carp and trout was studied. At 20 degrees C a significantly lower level of distribution (Vdarea) and a significantly shorter elimination half-life (T(1/2)beta) was achieved in both species compared to the 10 degrees C level. In carp the body clearance parameter (ClB(SDM)) was significantly higher at 20 degrees C compared to the value at 10 degrees C, whereas for trout this parameter was in the same order of magnitude for both temperatures. N4-acetylsulphadimidine (N4-SDM) was the main metabolite of SDM in both species at the two temperature levels. The relative N4-SDM plasma percentage in carp was significantly higher at 20 degrees C than at 10 degrees C, whereas there was in trout no significant difference. In neither species was the peak plasma concentration of N4-SDM (Cmax(N4-SDM)) significantly different at two temperatures. The corresponding peak time of this metabolite (Tmax(N4-SDM)) was significantly shorter at 20 degrees C compared to 10 degrees C in both carp and trout. In carp at both temperatures, acetylation occurs to a greater extent than hydroxylation. Only the 6-hydroxymethyl-metabolite (SCH2OH) was detected in carp, at a significant different level at the two temperatures. Concentrations of hydroxy metabolites in trout were at the detection level of the HPLC-method (0.02-micrograms/ml). The glucuronide metabolite (SOH-gluc.) was not detected in either species at the two temperatures. 相似文献