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141.
A 5-year-old Brazilian Fila dog was presented with a history of vision loss, alopecia, and generalized depigmentation of the skin and hair. Clinical examination confirmed generalized depigmentation and pyodermitis. On ophthalmic examination there was depigmentation at the eyelid mucocutaneous junction, associated with anterior uveitis, and bilateral posterior synechia at 360 degrees. Both the complete blood count and skin scraping were normal. Skin biopsy showed histiocytary lichenoid interface dermatitis with an absence of pigment within the queratinocytes, and a moderate lymphomononuclear infiltrate and predominance of histiocytes in the papilar derma suggestive of uveodermatologic syndrome. Clinical management consisted of oral and topical administration of prednisone, associated with 1% indometacine eye drops. Methylprednisone was also used twice via the subconjunctival route, at an interval of 15 days. To prevent the development of secondary glaucoma due to posterior synechiae, dorzolamide and timolol eye drops were indicated. Both dermatologic and ophthalmic signs showed good improvement, vision was preserved, and some repigmentation of the skin and hair occurred.  相似文献   
142.
Twenty-four strains of Salmonella enteritidis, isolated from several outbreaks of salmonellosis from different poultry farms in India, were checked for the plasmid profile and detection of virulence gene(s) by PCR. Most of the strains contained only a single plasmid of 55 kb. Additional plasmids of 23.2 kb and 8.7 kb were seen in one of the strains, and another strain carried only two plasmids of 23.2 kb and 8.7 kb. Four strains did not carry any plasmid. PCR amplification showed the presence of virulence-associated genes in all the isolates harbouring the 55 kb plasmid. Intraperitoneal inoculation of mice, with most of the strains carrying the 55 kb plasmid, caused 100% mortality. Most strains lacking the 55 kb plasmid were avirulent. In chickens, oral inoculation of the S. enteritidis strains carrying the 55 kb plasmid produced 40–100% mortality, with characteristic signs of salmonellosis. Oral inoculation of strains lacking the 55 kb plasmid did not cause any mortality. Hence, it appears that the large plasmid of S. enteritidis probably contributes towards virulence in mice and chickens.  相似文献   
143.
Enterobacterial repetitive intergenic consensus (ERIC) sequences are the repetitive elements present in the family enterobacteriacae. In the present study, ERIC-PCR (target ERIC sequence) was used for the molecular typing of 24 isolates of Salmonella serovars, namely abortusequi, choleraesuis, bareilly and dublin. In ERIC-PCR, seven molecular types were observed with ERIC-Cl primer, and nine molecular types with ERIC-C2 primer. When the results of both the ERIC-PCR were combined for molecular typing, 21 molecular types were observed, which indicated a high degree of discrimination. Both the ERIC primers are designed from the ERIC consensus sequence, yet they gave different profiles, indicating that they supplement each other. ERIC sequences were found to be useful targets for molecular typing. The different profiles observed appear to be due to differences in ERIC sequences and differences in inter-ERIC distance. The study indicates that ERIC-PCR is a very efficient tool for molecular typing of Salmonella species.  相似文献   
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Isoflavonoid production by callus cultures of Maackia amurensis   总被引:4,自引:0,他引:4  
Callus cultures were established from the different parts of Maackia amurensis plants and analyzed for isoflavonoids. The isoflavones daidzein, retuzin, genistein and formononetin and the pterocarpans maakiain and medicarpin were found to be produced by these cultures. The content of isoflavones and pterocarpans was essentially the same in cultures derived from leaf petioles, inflorescences and apical meristems of the plant. The maximal yield of isoflavones and pterocarpans in calluses was 20.8 mg/g cell dry wt., approximately four times higher than the content of the heartwood of M. amurensis plants. Unlike wild-growing plants, none of the cell cultures had the ability to accumulate stilbenes.  相似文献   
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148.
Lakes may be acid because of natural ecological conditions or because of anthropogenic activities. Apparently there has been a recent increase in acidity of many lakes in the northeastern United States. Factors that may be contributing to this increase include the use by utilities of precipitators, sulfur scrubbers, and tall stacks; the use of petroleum; and methods of combustion of fossil fuels.  相似文献   
149.
This study documents the clinical, histopathological, immunohistochemical and flow-cytometric findings in five horses with cutaneous non-epidermotropic malignant lymphoma (ML). The median survival time after discovery of the first subcutaneous nodules was 3.8 years (range 2-5 years: n=4). Histologically, the cutaneous ML had a pleiomorphic structure and contained a mixture of large reticulo-endothelial cells, medium-large sized lymphoid cells with a rounded nucleus and small nucleoli, many medium sized lymphoid cells with irregular nuclei, and some small lymphoid cells. Immunohistochemically (IHC) the lymphoid cells were positive for the pan-T-lymphocyte marker CD3 but negative for the B-lymphocyte markers CD21 and kappa and lambda immunoglobulin light chains. Although routine haematological examination revealed no abnormalities in the horses with cutaneous ML, changes in the peripheral blood lymphocyte population were apparent flow-cytometrically. Compared to clinically healthy horses, a decreased total percentage of cells was recorded in the lymphocyte gate. In three horses with cutaneous ML, an increase in CD4 positive cells was noticed in the monocyte gate. Flow-cytometric analysis of tumour cells collected by fine needle aspiration (FNA) suggested that the cutaneous MLs consisted primarily of CD4 and CD8 positive T-lymphocytes. The results were compared to those of a monomorphic multicentric T- and a monomorphic multicentric B-cell lymphoma. The results of immunohistochemistry and flow-cytometry were largely but not completely in accordance. In conclusion, the results of this study suggest that cutaneous non-epitheliotropic malignant lymphomas in the horse are of T-cell origin and that, after improvement of its accuracy, flow cytometric analysis of FNAs might become a useful aid to rapid tumour identification.  相似文献   
150.
The present study was carried out to assess the endocrine status and liver function in adult cows reared in polluted environment around different industrial units in India.The effect on endocrine system was examined by determination of plasma level of thyroid hormones, thyroxin (T4) (n=269) and triidothyronin (T3) (n=269), stress hormone cortisol (n=266), and reproductive hormones such as estradiol (n=84) and progesterone (n=84) in cows (>3 years) reared around different polluted industrial and non-polluted areas.The respective blood lead and cadmium concentration was also determined in all the cows.The mean plasma levels of both T3 and T4 were significantly (P<0.05) higher around lead zinc smelter (2.43+/-0.26 and 41.1+/-2.9nmol/L) and closed lead cum operational zinc smelter (1.81+/-0.16 and 42.4+/-6.2nmol/L), where the mean blood lead level (0.86+/-0.06 and 0.51+/-0.09mug/ml) was also significantly higher than that of cows (0.07+/-0.01mug/ml) from unpolluted areas.Regression analysis of data from 269 cows revealed a significant (P<0.01) positive correlation between the blood lead and plasma T3 (r=0.287) and T4 (r=0.173).The correlation between thyroidal hormones and the blood cadmium concentration (r=-0.079 and -0.48; P>0.05) was not significant.Plasma cortisol level had also a non-significant (P>0.05) correlation (r=-0.092) with blood lead level.However, the mean cortisol level (4.02+/-1.96nmol/L) of cows in phosphate rock mining areas was significantly (P<0.05) higher than that of controls (1.98+/-0.70nmol/L). The mean plasma estradiol level was significantly (P<0.05) higher in cows around closed lead cum operational zinc smelter (47.1+/-19.5pg/ml) than that of the control animals (21.8+/-3.9pg/ml) and in rest of the areas, the difference did not reach the statistical significance (P>0.05).The serum biochemical analysis in 36 cows around lead-zinc smelter with the highest mean blood lead level (0.86+/-0.06mug/ml) amongst all the industrial/urban areas surveyed, and in 15 animals from non-polluted areas revealed a significant positive correlation between blood lead and serum ALT (alanine transaminase) (r=0.688, P<0.01) and AST (aspartate transaminase) (r=0.390, P<0.01) and a negative correlation with serum total lipids (r=-0.337, P<0.05), total protein (r=-0.449, P<0.01) and albumin(r=-0.662, P<0.01). It is concluded from the study that the natural exposure to lead in polluted environments disturbs the endocrine profile and the higher blood lead level alters serum biochemical parameters indicative of liver functions.  相似文献   
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