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143.
Reticuloendotheliosis virus integration in the fowl poxvirus genome: not a recent event 总被引:3,自引:0,他引:3
Integration of reticuloendotheliosis virus (REV) into the genome of fowl poxvirus (FPV) has been reported recently. With a view to determine whether this event had occurred in the past, we screened by polymerase chain reaction (PCR) for the presence of REV provirus in the DNAs of nine avian poxviruses, some of which had been lyophilized 50 yr ago. For REV, 5' long terminal repeat (LTR) and REV envelope sequences were amplified, whereas for FPV, the major envelope antigen gene and the region flanking REV sequences were amplified. In six of seven FPV strains examined, the specific PCR amplicons were obtained for both REV provirus and FPV sequences. One isolate in which presence of REV 5' LTR and envelope was not detected by PCR, a LTR remnant was detected by Southern hybridization. Interestingly, no REV sequence was detected in either canary poxvirus or pigeon poxvirus genome. These observations indicate that REV integration in the FPV genome is not a recent phenomenon but probably occurred prior to 1949. 相似文献
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Kim DY Mauldin GE Hosgood G Cho DY 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(4):610-612
Melanocytic tumors are relatively common in dogs and most often occur in the oral cavity, lip, skin, digit, and eye. There are notable differences in the behavior of these tumors, depending on their anatomical location. The majority of oral melanomas and two-thirds of melanomas arising from the digit are malignant, whereas most of melanomas originating from the haired skin are benign. The anus and perianal areas are very uncommon sites for melanocytic tumors in domestic animals except horses, and most of those tumors in horses are malignant. To our knowledge, perianal malignant melanoma has not been reported in the dog and its prognosis is unknown. 相似文献
147.
Beef quality traits of heifer in comparison with steer,bull and cow at various feeding environments 下载免费PDF全文
Bandugula Venkata Reddy Allur S. Sivakumar Dawoon W. Jeong Yang‐Byung Woo Sang‐June Park So‐Young Lee Ji‐Yeon Byun Chang‐Ho Kim Soo‐Hyun Cho Inho Hwang 《Animal Science Journal》2015,86(1):1-16
The present review has been focused largely on the sex type differences in beef quality among heifers, cows, steers and bulls in various feeding environments. Genetic groups, feeding systems and gender are the major factors that change carcass characteristics and fatty acid profiles of cattle. Studies identified that heifer beef has super characteristics in eating quality and a better healthy composition in fatty acids than steer, cow and bull. Diet influences the variation of fatty acid profile; particularly the level of polyunsaturated fatty acids (PUFA) interacts with breed and sex. Animals finished in pasture systems were reported to show better ratios of PUFA/ saturated fatty acids and n‐6/n‐3. Carcasses of roughage‐fed beef are lighter and have less marbling and lower quality grades but have higher cutability than carcasses of grain‐fed bulls. Heifers and cows are reported to deposit more fat than steers and bulls. Among males, lower production of testosterone by steers favors more fat thickness compared with bulls. Marbling greatly varies among cattle belonging to different sexes, and particularly, females have genetic makeup that efficiently controls deposition. The current review identified that heifers can be a premium beef brand, while steer beef currently take a large part of market share across the world. 相似文献
148.
Jeong CK Lee HY Kim SB Choi SJ Kim JH Kim K Han SS Lee HS 《Pest management science》2001,57(5):427-431
To investigate the hepatic metabolism of the new insecticide flupyrazofos [O,O-diethyl O-(1-phenyl-3-trifluoromethylpyrazol-5-yl) phosphorothioate], isolated rat liver was perfused with flupyrazofos under single-pass conditions. In outflow perfusate and bile, 1-phenyl-3-trifluoromethyl-5-hydroxyprazole (PTMHP), PTMHP-sulfate and PTMHP-glucuronide conjugates were identified as the metabolites of flupyrazofos. However, O,O-diethyl O-(1-phenyl-3-trifluoromethylpyrazol-5-yl) phosphate (flupyrazofos oxon) was not detected. A HPLC method with UV detection was used to investigate the hepatic disposition of flupyrazofos and its metabolite PTMHP. The concentrations of flupyrazofos, PTMHP and PTMHP conjugates in outflow perfusate reached steady-state levels within 20 min after commencing perfusion of 7.3 microM flupyrazofos. At steady state, the mean extraction ratio of flupyrazofos was 0.93 (+/- 0.01) and clearance was 26.1 (+/- 0.2) ml min-1 which nearly approached perfusate flow rate (28 ml min-1). PTMHP accounted for 55.7 (+/- 5.8)% of eliminated flupyrazofos and was recovered as unchanged PTMHP, PTMHP-sulfate and PTMHP-glucuronide in the bile as well as the outflow perfusate. 相似文献
149.
Hirako S Kim HJ Shimizu S Chiba H Matsumoto A 《Journal of agricultural and food chemistry》2011,59(24):13353-13359
We examined the effects of low-dose fish oil ingestion on hepatic lipid accumulation caused after high cholesterol feeding in C57BL/6J mice. The mice were fed purified experimental diets consisting of 20 energy % (en%) safflower oil (SO or SO/CH), 2 en% fish oil + 18 en% safflower oil (2FO or 2FO/CH), or 5 en% fish oil + 15 en% safflower oil (5FO or 5FO/CH) with or without 2 weight % (wt %) cholesterol for 8 weeks. Hepatic triglyceride and total cholesterol contents were significantly lower in groups that were fed diets containing fish oil and cholesterol than in those that were fed safflower oil and cholesterol. The hepatic mRNA levels of fatty acid synthase (FAS) were lower in groups fed cholesterol or fish oil. Fatty acid oxidation-related hepatic gene expressions were higher in fish oil-fed groups. Fecal cholesterol excretion was higher in all cholesterol-fed groups; cholesterol excretion was high in groups fed fish oil and cholesterol. These results suggest that low-dose fish oil diets improve lipid metabolism by modifying the expression of lipid metabolism-related genes in the liver and increasing fecal cholesterol excretion. 相似文献
150.
Predictors of pregnancy and postpartum haemoglobin concentrations in low-income women 总被引:1,自引:0,他引:1
OBJECTIVE: Pregnancy and postpartum iron status is of great public health importance, yet few studies have examined predictors of haemoglobin (Hb) concentration during this time. We identified predictors of Hb from 24 weeks' gestation until delivery and from 4 to 25 weeks postpartum. DESIGN: Blood was drawn as many as four times during care: at the initial visit, at 24-29 weeks' gestation, at delivery and postpartum. A longitudinal, multivariable linear regression model was used to predict Hb concentration. SETTING: A public health clinic in Raleigh, North Carolina.Subjects: n=520 women who participated in the Iron Supplementation Study. RESULTS: Hb concentration at the previous blood draw, short stature, non-Hispanic white ethnicity/race, >12 years of education and smoking were positive predictors of pregnancy and postpartum Hb concentrations. Iron supplement use was a positive predictor, while inadequate weight gain and severe nausea/vomiting were negative predictors of gestational Hb. A high infant birth weight and postpartum haemorrhage were negative predictors of postpartum Hb. Pre-pregnancy body mass index had a slight positive relationship with gestational Hb, but had a strong negative relationship with postpartum Hb. The longitudinal model also confirmed the typical pattern of gestational Hb concentration. As the number of weeks between the initial visit and the 24- to 29-week visit increased, Hb at 24-29 weeks' gestation decreased. As gestational age increased from 24 weeks until delivery, Hb concentration increased as well. CONCLUSIONS: The predictors identified here could be used in clinical settings to target high-risk women for intervention. 相似文献