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排序方式: 共有677条查询结果,搜索用时 15 毫秒
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Daniela Simon Dorina Schoenrock Ingo Nolte Wolfgang Baumgrtner Ronnie Barron Reinhard Mischke 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2009,38(4):521-528
Background: Mammary tumors are the most common neoplasms in female dogs. Malignant tumors may carry a poor prognosis and necessitate surgery. Few data are available on the value of cytologic examination as a diagnostic or prognostic tool for mammary tumors in dogs. Objectives: The objectives of this study were to determine whether cytologic findings in fine‐needle aspirate specimens of canine mammary tumors correlate with histopathologic results and whether the cytologic diagnosis is associated with postoperative outcome. Methods: In this prospective study, fine‐needle aspirate samples were obtained from 50 mammary tumors in 50 dogs. Results of cytologic and histopathologic examination were compared, using the histologic diagnosis as the reference method. Kaplan–Meier log rank analysis was used to evaluate univariate association of the cytologic diagnosis with duration of survival, local control, and metastasis‐free interval. Results: Adequate cytologic samples were obtained in 43/50 (86%) cases. The cytologic diagnosis correlated with the histologic diagnosis for benign and malignant tumors in 40/43 (93%) and 35/43 (81%) cases, respectively. Cytologic examination had a sensitivity of 88% and a specificity of 96% for the diagnosis of malignancy. The cytologic diagnosis had significant univariate association with duration of survival (P=.016), recurrence‐free interval (P=.003), and metastasis‐free interval (P=.014). Conclusions: Cytologic examination of mammary tumors in the dog has satisfactory accuracy, sensitivity, and specificity for the diagnosis of malignancy and is associated with postoperative outcome. Further studies on the diagnostic accuracy of cytology as well as multivariate analysis of its preoperative prognostic value in mammary tumors in the dog are warranted. 相似文献
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Matias Bermann Daniela Lourenco Vivian Breen Rachel Hawken Fernando Brito Lopes Ignacy Misztal 《Journal of animal science》2021,99(4)
The introduction of animals from a different environment or population is a common practice in commercial livestock populations. In this study, we modeled the inclusion of a group of external birds into a local broiler chicken population for the purpose of genomic evaluations. The pedigree was composed of 242,413 birds and genotypes were available for 107,216 birds. A five-trait model that included one growth, two yield, and two efficiency traits was used for the analyses. The strategies to model the introduction of external birds were to include a fixed effect representing the origin of parents and to use unknown parent groups (UPG) or metafounders (MF). Genomic estimated breeding values (GEBV) were obtained with single-step GBLUP using the Algorithm for Proven and Young. Bias, dispersion, and accuracy of GEBV for the validation birds, that is, from the most recent generation, were computed. The bias and dispersion were estimated with the linear regression (LR) method,whereas accuracy was estimated by the LR method and predictive ability. When fixed UPG were fit without estimated inbreeding, the model did not converge. In contrast, models with fixed UPG and estimated inbreeding or random UPG converged and resulted in similar GEBV. The inclusion of an extra fixed effect in the model made the GEBV unbiased and reduced the inflation. Genomic predictions with MF were slightly biased and inflated due to the unbalanced number of observations assigned to each metafounder. When combining local and external populations, the greatest accuracy can be obtained by adding an extra fixed effect to account for the origin of parents plus UPG with estimated inbreeding or random UPG. To estimate the accuracy, the LR method is more consistent among scenarios, whereas the predictive ability greatly depends on the model specification. 相似文献
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Daniela Proverbio Debora Groppetti Eva Spada Roberta Perego 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2009,38(3):332-336
Background: Serum cortisol concentration is often measured in dogs for the diagnosis and monitoring of adrenal disease. An enzyme‐linked fluorescent assay (VIDAS method) on the MiniVidas analyzer has been validated for the measurement of cortisol concentration in human serum and could have applications for canine samples. Objective: The aim of this study was to compare canine cortisol results obtained using the VIDAS method with those obtained using the IMMULITE‐2000 immunoassay, which has previously been validated for canine serum. Methods: The concentration of cortisol in 40 canine serum samples was determined concurrently with the VIDAS and IMMULITE methods, the latter as the reference method. Pearson's correlation coefficient, linear, and Deming regression analyses and Bland–Altman analysis were used to compare the 2 methods. Acceptability of the new method was judged using a medical decision chart (MEDx chart). Results: Cortisol concentrations obtained with the IMMULITE method ranged from 23.1 to 1380 nmol/L. Correlation (r=.977) and simple linear regression (slope=1.0722, confidence interval [CI] 0.996–1.148; intercept=?4.799, CI ?42.838 to 33.240) revealed no proportional or constant error. Based on Deming regression and a Bland–Altman plot the 2 methods gave comparable results. The MEDx chart indicated that performance of the new method was good at decision limits of 40, 132, and 480 nmol/L. Conclusion: Results of the VIDAS method were comparable to those of the IMMULITE‐2000 reference method such that the VIDAS may be used as an alternative assay to evaluate serum cortisol concentration in dogs for the diagnosis of adrenal disease. 相似文献
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Romani A Vignolini P Isolani L Ieri F Heimler D 《Journal of agricultural and food chemistry》2006,54(4):1342-1346
Flavonoids and hydroxycinnamic derivatives of turnip tops (Brassica rapa L. subsp. sylvestris L.) were characterized for the first time in four samples from different origins. Turnip tops exhibit a high polyphenols content (ranging from 107 to 191 mg/100 g, fresh weight) and a good antiradical activity, determined with the DPPH* test. After a liquid-liquid extraction and fractionation procedures, most flavonoids (isorhamnetin, kaempferol, and quercetin glycosides) and hydroxycinnamic derivatives were identified by means of HPLC-DAD/MS techniques. Isorhamnetin glycosides were the main flavonoid derivatives, differing from that found in the vegetables belonging to the Brassica oleracea group. 相似文献
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Häsler B Hernandez JA Reist M Sager H Steiner-Moret C Staubli D Stärk KD Gottstein B 《Veterinary parasitology》2006,137(3-4):222-230
We conducted a longitudinal study to follow-up the anti-Neospora caninum serologic status in 30 initially seropositive and 83 initially seronegative cows during their pregnancy. Study cows were blood-sampled every other month during pregnancy until parturition. Blood serum samples were screened for anti-N. caninum antibodies by ELISA. Cows that seroconverted were re-tested by immunoblot as a confirmation test. Among 30 seropositive cows, 28 cows remained seropositive during the whole pregnancy, whereas 2 cows transiently tested negative at least once during pregnancy. Among 83 seronegative cows, 82 cows remained seronegative and 1 cow tested positive three times during the sixth, eighth and last month of pregnancy. As only 2 out of 30 seropositive animals and 1 out of 83 animals changed their serologic status during pregnancy, the study results indicate that there is only a minor temporal instability of anti-N. caninum antibody reactivity in adult cattle. 相似文献
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