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101.
A total of 6195 cattle were enrolled in this observational study. Serum antibody concentrations to bovine herpesvirus 1 (BHV1) and bovine viral diarrhoea virus (BVDV) were measured at entry to and exit from backgrounding facilities to assess their statuses on arrival and the extent of seroconversion to these viruses during backgrounding. The backgrounding facilities were contiguous with five feedlots in: Queensland (two sites), New South Wales, South Australia and Western Australia. Cattle were held in the backgrounding facilities for a minimum of 29 days and a median of 34 days. On backgrounding facility entry, 32.7% of the study population was seronegative to BVDV, but 85.7% was seronegative to BHV1. After commingling in the backgrounding facilities, of the cattle that were seronegative on backgrounding facility entry, 33.9% and 30.3% showed a serological increase to BVDV and BHV1, respectively. At backgrounding facility exit, when cattle were placed in their feedlots, 19.6% and 59.1% were seronegative to BVDV and BHV1, respectively, and 0.26% were persistently infected with BVDV. There was a strong association between seroincrease to BVDV and seroincrease to BHV1 (P = 0.005) at animal level in cohorts known to contain an animal persistently infected with BVDV. 相似文献
102.
A genome-wide association study of type 2 diabetes in Finns detects multiple susceptibility variants
Scott LJ Mohlke KL Bonnycastle LL Willer CJ Li Y Duren WL Erdos MR Stringham HM Chines PS Jackson AU Prokunina-Olsson L Ding CJ Swift AJ Narisu N Hu T Pruim R Xiao R Li XY Conneely KN Riebow NL Sprau AG Tong M White PP Hetrick KN Barnhart MW Bark CW Goldstein JL Watkins L Xiang F Saramies J Buchanan TA Watanabe RM Valle TT Kinnunen L Abecasis GR Pugh EW Doheny KF Bergman RN Tuomilehto J Collins FS Boehnke M 《Science (New York, N.Y.)》2007,316(5829):1341-1345
Identifying the genetic variants that increase the risk of type 2 diabetes (T2D) in humans has been a formidable challenge. Adopting a genome-wide association strategy, we genotyped 1161 Finnish T2D cases and 1174 Finnish normal glucose-tolerant (NGT) controls with >315,000 single-nucleotide polymorphisms (SNPs) and imputed genotypes for an additional >2 million autosomal SNPs. We carried out association analysis with these SNPs to identify genetic variants that predispose to T2D, compared our T2D association results with the results of two similar studies, and genotyped 80 SNPs in an additional 1215 Finnish T2D cases and 1258 Finnish NGT controls. We identify T2D-associated variants in an intergenic region of chromosome 11p12, contribute to the identification of T2D-associated variants near the genes IGF2BP2 and CDKAL1 and the region of CDKN2A and CDKN2B, and confirm that variants near TCF7L2, SLC30A8, HHEX, FTO, PPARG, and KCNJ11 are associated with T2D risk. This brings the number of T2D loci now confidently identified to at least 10. 相似文献
103.
104.
Manley CA Leibman NF Wolchok JD Rivière IC Bartido S Craft DM Bergman PJ 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2011,25(1):94-99
Background: Malignant melanoma of dogs is a highly aggressive neoplasm and is the 2nd most common digit tumor. Metastatic disease is a common sequela for which few effective treatment options exist. Studies show that xenogeneic tyrosinase DNA vaccination yields immune responses and prolongation of survival in dogs with oral malignant melanoma. Objectives/Hypothesis: Describe clinical findings and tumor characteristics of a cohort of dogs with digit malignant melanoma, and evaluate the prognostic utility of a proposed staging system. Determine if a novel xenogeneic DNA vaccine is safe and potentially effective for treatment of dogs with digit melanoma. Animals: Fifty‐eight dogs with digit malignant melanoma treated at the Animal Medical Center between 2004 and 2007. Methods: Retrospective, medical records review of dogs with digit melanoma treated with xenogeneic DNA vaccine. Results: Overall median survival time (MST) for dogs treated with loco‐regional control and xenogeneic DNA vaccine was 476 days with a 1‐year survival rate of 63%. MST for dogs presenting with metastasis was 105 days versus 533 days for dogs presenting without metastasis (P < .0001). Forty‐eight percent of the dogs in the latter group were alive at 2 and 3 years. A proposed staging system proved prognostic with stages I–IV dogs surviving >952, >1,093, 321, and 76 days, respectively. Conclusions and Clinical Importance: The xenogeneic murine tyrosinase DNA vaccine was safe and appears effective when used in conjunction with local and regional disease control. The proposed staging system was prognostic in this study and future studies might benefit from utilizing this staging system. 相似文献
105.
Although it is known that Parkinson's disease results from a loss of dopaminergic neurons in the substantia nigra, the resulting alterations in activity in the basal ganglia responsible for parkinsonian motor deficits are still poorly characterized. Recently, increased activity in the subthalamic nucleus has been implicated in the motor abnormalities. To test this hypothesis, the effects of lesions of the subthalamic nucleus were evaluated in monkeys rendered parkinsonian by treatment with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). The lesions reduced all of the major motor disturbances in the contralateral limbs, including akinesia, rigidity, and tremor. This result supports the postulated role of excessive activity in the subthalamic nucleus in Parkinson's disease. 相似文献
106.
Marine sponges are an extremely rich and important source of natural products. Mariculture is one solution to the so-called "supply problem" that often hampers further studies and development of novel compounds from sponges. We report the extended culture (767 days) at sea in depths of 10 and 20 m of three sponge species: Negombata magnifica, Amphimedon chloros and Theonella swinhoei that produce latrunculin-B, halitoxin and swinholide-A, respectively. Since sponge-associated microorganisms may be the true producers of many of the natural products found in sponges and also be linked to the health of the sponges, we examined the stability of the bacterial communities in cultured versus wild sponges. Growth rate of the sponges (ranging from 308 to 61 and -19 (%)(year(-1)) in N. magnifica, A. chloros and T. swinhoei, respectively) differed significantly between species but not between the two depths at which the species were cultivated. Survivorship varied from 96% to 57%. During culture all species maintained the content of the desired natural product. Denaturing gradient gel electrophoresis analysis of the sponge-associated bacterial consortia revealed that differences existed between cultured and wild sponges in T. swinhoei and A. chloros but the communities remained quite stable in N. magnifica. The cultivation technique for production of natural products was found to be most appropriate for N. magnifica, while for T. swinhoei and A. chloros it was less successful, because of poorer growth and survival rates and shifts in their bacterial consortia. 相似文献
107.
George M. Linz David L. Bergman H. Jeffrey Homan William J. Bleier 《Crop Protection》1995,14(8):625-629
In August 1992, we treated cattail-dominated wetlands in four 23-km2 blocks with aerially-applied glyphosate herbicide (5.3 1 ha−1). Four other blocks of wetlands were left untreated (reference). We assessed the effects of cattail (Typha spp.) reduction on roosting blackbird (Icterinae) numbers and sunflower damage within the blocks. Blackbird numbers did not differ between posttreatment years (P = 0.453) or between treated and reference wetlands (P = 0.469), averaging 6227 ± 4185 (SE) birds per block. Sunflower damage within blocks was similar between posttreatment years (P = 0.250) and did not vary (P = 0.460) between treatments (
). However, positive linear relationships were detected between blackbird numbers (y) and hectares of live cattails (x) [(y = 442.2 x)] (P = 0.006) and between blackbird numbers (x) and kilograms of sunflower lost per hectare per year (y) [(y = 0.003 x)] (P = 0.0001). Cattail reduction appears to discourage roosting blackbirds and, thus, may reduce sunflower damage in adjacent fields. 相似文献
108.
Lotta Berntzon Sven Erasmie Narin Celepli Johan Eriksson Ulla Rasmussen Birgitta Bergman 《Marine drugs》2013,11(8):3091-3108
Cyanobacteria produce a range of secondary metabolites, one being the neurotoxic non-protein amino acid β-N-methylamino-L-alanine (BMAA), proposed to be a causative agent of human neurodegeneration. As for most cyanotoxins, the function of BMAA in cyanobacteria is unknown. Here, we examined the effects of BMAA on the physiology of the filamentous nitrogen-fixing cyanobacterium Nostoc sp. PCC 7120. Our data show that exogenously applied BMAA rapidly inhibits nitrogenase activity (acetylene reduction assay), even at micromolar concentrations, and that the inhibition was considerably more severe than that induced by combined nitrogen sources and most other amino acids. BMAA also caused growth arrest and massive cellular glycogen accumulation, as observed by electron microscopy. With nitrogen fixation being a process highly sensitive to oxygen species we propose that the BMAA effects found here may be related to the production of reactive oxygen species, as reported for other organisms. 相似文献
109.
Sharifa Sultana Dipti Christine Bergman Siti Dewi Indrasari Theja Herath Robert Hall Hueihong Lee Fatemeh Habibi Priscila Zaczuk Bassinello Eduardo Graterol Julie P Ferraz Melissa Fitzgerald 《Rice》2011,5(1):1-18
Elevated Na+ levels in agricultural lands are increasingly becoming a serious threat to the world agriculture. Plants suffer osmotic and ionic stress under high salinity due to the salts accumulated at the outside of roots and those accumulated at the inside of the plant cells, respectively. Mechanisms of salinity tolerance in plants have been extensively studied and in the recent years these studies focus on the function of key enzymes and plant morphological traits. Here, we provide an updated overview of salt tolerant mechanisms in glycophytes with a particular interest in rice (Oryza sativa) plants. Protective mechanisms that prevent water loss due to the increased osmotic pressure, the development of Na+ toxicity on essential cellular metabolisms, and the movement of ions via the apoplastic pathway (i.e. apoplastic barriers) are described here in detail. 相似文献
110.