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71.
Molecular characterization and phylogenetic study of newcastle disease virus isolates from recent outbreaks in eastern Uganda 总被引:2,自引:0,他引:2 下载免费PDF全文
Otim MO Christensen H Jørgensen PH Handberg KJ Bisgaard M 《Journal of clinical microbiology》2004,42(6):2802-2805
Newcastle disease virus isolates from chickens in eastern Uganda in 2001 were found to be velogenic by fusion protein cleavage site sequence analysis and biological characterization; the intracerebral pathogenicity index was 1.8. Analysis of their hemagglutinin-neuraminidase protein gene sequences revealed a novel genotype unrelated to those that caused previous outbreaks. 相似文献
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Bjerregaard P Johansen P Mulvad G Pedersen HS Hansen JC 《Environmental health perspectives》2004,112(15):1496-1498
Although blood lead levels have declined in Greenland, they are still elevated despite the fact that lead levels in the Greenland environment are very low. Fragments of lead shot in game birds have been suggested as an important source of dietary exposure, and meals of sea birds, particularly eider, contain high concentrations of lead. In a cross-sectional population survey in Greenland in 1993-1994, blood lead adjusted for age and sex was found to be associated with the reported consumption of sea birds. Participants reporting less than weekly intake of sea birds had blood lead concentrations of approximately 75 microg/L, whereas those who reported eating sea birds several times a week had concentrations of approximately 110 microg/L, and those who reported daily intake had concentrations of 170 microg/L (p = 0.01). Blood lead was not associated with dietary exposure to other local or imported food items. 相似文献
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Bastlund JF Jennum P Mohapel P Vogel V Watson WP 《Journal of neuroscience methods》2004,138(1-2):65-72
Implanted radiotelemetry has been used for the measurement of cortical electroencephalogram (EEG), locomotor activity, body temperature and cardiovascular parameters. This technique allows high quality data acquisition from freely moving animals with no complications of externalised apparatus. This paper focuses on the methodology for short and long-term monitoring of epileptiform activity by simultaneous cortical EEG, hippocampal (HC) EEG and electromyogram (EMG) in rats. The circadian rhythm of temperature (CRT) was monitored after surgery to estimate the need for post surgical recovery of animals. Different placements of EMG electrodes were assessed in order to minimise artefacts and increase sensitivity. The occurrence of epileptiform ictal and interictal activity following an acute injection of either 40 mg/kg pentylenetetrazole (PTZ) or 13.8 mg/kg kainic acid (KA) was investigated. The occurrence of spontaneous seizures was also monitored 5-8 weeks after administration of KA. The present study demonstrated a sensitive method for monitoring cortical EEG, hippocampal EEG and EMG short and long-term by implantable radiotelemetry in freely moving rats. 相似文献
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Condyloma in pregnancy is strongly predictive of juvenile-onset recurrent respiratory papillomatosis 总被引:8,自引:0,他引:8
OBJECTIVE: To assess the risk of juvenile-onset recurrent respiratory papillomatosis conferred by a maternal history of genital warts in pregnancy, and to identify additional cofactors such as the method of delivery (cesarean versus vaginal) and procedures or complications during pregnancy. METHODS: A retrospective cohort design was used to evaluate maternal and infant characteristics associated with respiratory papillomatosis among Danish births between 1974 and 1993. Using data from Danish registries, we identified 3033 births with a maternal history of genital warts during pregnancy. Fifty-seven respiratory papillomatosis cases were identified by review of medical records from ear, nose, and throat departments. RESULTS: Seven of every 1000 births with a maternal history of genital warts resulted in disease in the offspring, corresponding to a 231.4 (95% confidence interval 135.3, 395.9) times higher risk of disease relative to births without a maternal history of genital warts. In women with genital warts, delivery times of more than 10 hours were associated with a two-fold greater risk of disease. Cesarean delivery was not found to be protective against respiratory papillomatosis, and no other procedures or complications during pregnancy were observed to increase the risk of respiratory papillomatosis. CONCLUSION: A maternal history of genital warts in pregnancy is the strongest risk factor for respiratory papillomatosis in the child. Future studies should examine the efficacy of genital wart treatment for the prevention of disease. 相似文献
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Friis H Gomo E Nyazema N Ndhlovu P Krarup H Madsen PH Michaelsen KF 《Journal of acquired immune deficiency syndromes (1999)》2003,33(1):74-81
BACKGROUND: Viral load is a determinant of HIV-1 progression and transmission. Iron status and the phenotype of haptoglobin, a heme-binding acute phase reactant, may be determinants of viral load. We aimed to describe the effect of iron status, haptoglobin phenotype (Hp), and other predictors on HIV-1 viral load. METHODS: Based on a cross-sectional study among 1669 antenatal care attenders (22-35 weeks) in Zimbabwe, 526 (31.5%) were found to be HIV infected. The role of season, age, gravidity, gestational age, malaria parasitemia, Hp, and elevated serum alpha(1)-antichymotrypsin (ACT) as well as serum ferritin, folate, retinol, and beta-carotene on HIV viral load among the 526 HIV-infected women was assessed using multiple linear regression analysis. RESULTS: The distribution of Hp 1-1 (32%), Hp 2-1 (48%), and Hp 2-2 (20%) was not different from that of 53 uninfected women. Mean viral load was 3.85 log(10) (95% CI: 3.77-3.93) genome equivalents (geq)/mL, ranging from 3.77 (95% CI: 3.64-3.90) geq/mL in women with Hp 1-1 to 4.05 (95% CI: 3.81-4.21) geq/mL in women with Hp 2-2. With elevated serum ACT controlled for, women with Hp 2-2 had viral loads twice (95% CI: 1.4-4.0, p =.002) that of women with Hp 1-1, whereas those with serum ferritin <6 micro g/L had viral loads less than one third (95% CI: 0.13-0.53, p =.013) that of women with serum ferritin >24 micro g/L. Viral loads were also higher in women enrolled in the early rainy season compared with the dry season, in gravidae 4+ compared with gravidae 1 through 3, and in those with moderately elevated compared with low serum alpha(1)-antichymotrypsin, but neither age, gestational age, serum folate, serum retinol, nor serum beta-carotene were predictors. CONCLUSION: Storage iron, Hp 2-2, and elevated ACT are independent positive predictors of HIV-1 viral load. The positive relationship between serum ferritin and viral load was not the result of an acute phase response or iron accumulation with advanced HIV infection. A possible detrimental role of iron in HIV infection would have serious public health implications. 相似文献
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