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991.
The immunophenotype of tumor cells and inflammatory infiltrate associated with cutaneous melanocytic lesions (29 melanocytomas, two malignant melanomas, and 23 residual lesions) from 54 adult Iberian and Iberian x Duroc pigs were examined using a panel of nine antibodies. All neoplastic cells were vimentin+, cytokeratin-, and alpha-1-antitrypsin- and the majority were S100+, whereas all pigmented macrophages were vimentin+, cytokeratin-, and S100- and most expressed alpha-1-antitrypsin. Regressing tumors were characterized by zones with low density of neoplastic cells accompanied by heavy infiltration of CD3+ T lymphocytes, whereas zones with high density of neoplastic cells showed very low numbers of CD3+ T lymphocytes. The infiltrate of CD79a+ B cells and IgG, IgM, and IgA plasma cells was low. The majority of lymphocytes of the peri- and intratumoral infiltrate were major histocompatibility complex class II+, but neoplastic cells did not express class II antigen. The 17 residual lesions examined were composed of macrophages containing abundant melanin pigment and low to moderate numbers of CD3+ T lymphocytes. The results of the present study suggest that the local cellular immune response plays a crucial role in the host response that induces regression of cutaneous melanomas and melanocytomas of the Iberian and crossbred Iberian x Duroc pigs.  相似文献   
992.
The possible interference of haemolysis, lipaemia, bilirubinaemia and fibrinogen on capillary zone electrophoresis of canine samples were studied. Solutions of haemoglobin, lipid and bilirubin were prepared and mixed with serum aliquots to make up samples containing different concentrations of the putative interferent substance. In addition, samples of serum and plasma were assayed to assess the influence of fibrinogen. Haemolysis and lipids produced a change in electropherogram morphology giving an interference peak located in the beta-2 region when haemoglobin was increased, and in the alpha-2 region when lipids were increased. A rise in concentration of these interferents caused an increase in the beta and alpha-2 fractions respectively, and a decrease in the other fractions. Bilirubin did not alter morphology but gave an increase in the albumin and alpha-1 and a decrease in the alpha-2 and beta-2 fractions. No differences were found between serum and plasma samples, and fibrinogen did not produce any additional peak.  相似文献   
993.
The design of experiments (DOE) was used in the development of a laboratory procedure for the extraction of tannins from three infant food types comprising different ingredients of vegetable origin and meat. The diversity of vegetables included in the product formulas required the use of DOE to establish parameters that maximize the recovery of tannins using a central composite rotatable design. Once the experimental results from the DOE were obtained, response surface methodology was used to find the best analytical conditions for samples comprising different ingredients. Sample weight was found to be a critical factor in tannin extraction from foods. Different optimal conditions were obtained for samples including soya in the formula.  相似文献   
994.
995.
This study evaluated the time course distribution of rabbit haemorrhagic disease virus (RHDV) structural protein VP60 in tissues from experimentally infected rabbits from three different age groups. Viral VP60 antigen could not be detected in tissue samples from animals under four weeks, and only a few hepatocytes (0.01 to 0.2 per cent) were stained in the 6-week-old animals. A 6-week-old rabbit euthanised at 72 hpi showed VP60-labelling in hepatocytes and macrophages close to areas of inflammation. Viral VP60 antigen was detected as early as 12 hpi in a few hepatocytes (0.03 per cent) from adult animals. Within this age group, the extent of hepatocyte labelling considerably increased at 18 (3.0 per cent), 24 (25.5 per cent), 36 (50 per cent) and 48 (60 per cent) hpi. Extrahepatic viral VP60 antigen was also detected at 36 and 48 hpi in spleen macrophages and lymphocytes from adult rabbits. These findings support the hypothesis that the hepatocyte is the only cell type in the liver able to support RHDV replication almost immediately after viral infection.  相似文献   
996.
An 11-year-old entire female German shepherd dog was presented with a progressive non-painful exophthalmos of the right eye. Ultrasonographic examination revealed a solid and well-defined orbital mass compressing the globe. Thoracic radiography revealed multiple pulmonary metastases of different sizes. The histopathological and immunohistochemical features of both the retrobulbar tumour and pulmonary metastases were consistent with an anaplastic astrocytoma. This represents an unusual case of an extracranial astrocytoma with multiple pulmonary metastases. The clinical features and the ultrasonographic, histopathological and immunohistochemical findings are described.  相似文献   
997.
998.
The purpose of this study was to determine the photoprotective properties of the methanolic extract of Buddleja scordioides, as well as verbascoside and linarin which were isolated from this extract, and linarin acetate prepared in the laboratory. The photoprotective effect of substances against UV-B induced cellular death was evaluated by challenge experiments using Escherichia coli. Verbascoside and linarin acetate showed the highest protection. The sun protection factor (SPF) of the methanolic extract, linarin, linarin acetate, and verbascoside was evaluated by guinea pig bioassays. Verbascoside showed the largest SPF measurement.  相似文献   
999.
A Pinus radiata progeny trial was established in 2003 on three low fertility sites in Galicia to study the relevance of genotype×fertilization interaction. At each site, twenty seven open pollinated families derived from plus trees selected in mature plantations in Galicia (NW Spain) were planted under 9 fertilization treatments following a split-plot design. One year after planting, P and Mg fertilization significantly increased height growth whereas N did not affect or even significantly reduced height growth. Fertilization×site interaction was not significant indicating parallel responses to fertilization in the three sites. Fertilization × genotype interaction was significant in only one site, suggesting some genetic variation in the nutrient use efficiency among the studied genotypes. However, the lack of a significant interaction in the other two sites, and the lack of consistence among the genotypic stability in relation to fertilization across sites, hinder the possibility of breeding in relation to the nutrient efficiency of the genotypes. Indications for further research are given.  相似文献   
1000.
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