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91.
I. T. D. Petty K. W. Buck R. H. A. Coutts 《European journal of plant pathology / European Foundation for Plant Pathology》1988,94(1):3-7
Samenvatting Aangetoond werd datPetunia hybrida systemisch kan worden geïnfecteerd met het tomato golden mosaic virus (TGMV), een virus dat behoort tot de groep van de geminivirussen. Mechanische inoculatie van petuniaplanten met TGMV gaf in de systemisch geïnfecteerde bladeren symptomen, die eerder in een aantal andere Solanaceae waren waargenomen. Daar in eerdere proeven petunia niet met TGMV kon worden geïnfecteerd en DNA-replicatie en symptoomontwikkeling wel optrad in, voor de beide genomen van het virus, transgene planten, werd gesuggereerd dat het hier een geval betrof van uitbreiding van de waardplantenreeks.De hier gepresenteerde resultaten kunnen echter tot andere conclusies leiden. Het is namelijk mogelijk, dat bepaalde F1-hybriden van petunia resistenter zijn tegen het virus. Verschillen in de symptoomontwikkeling zijn echter ook niet uit te sluiten en zouden veroorzaakt kunnen worden door premunitie als gevolg van de aanwezigheid van het manteleiwit in opnieuw geïnfecteerde cellen. 相似文献
92.
Chen Y Cann MJ Litvin TN Iourgenko V Sinclair ML Levin LR Buck J 《Science (New York, N.Y.)》2000,289(5479):625-628
Spermatozoa undergo a poorly understood activation process induced by bicarbonate and mediated by cyclic adenosine 3',5'-monophosphate (cAMP). It has been assumed that bicarbonate mediates its effects through changes in intracellular pH or membrane potential; however, we demonstrate here that bicarbonate directly stimulates mammalian soluble adenylyl cyclase (sAC) activity in vivo and in vitro in a pH-independent manner. sAC is most similar to adenylyl cyclases from cyanobacteria, and bicarbonate regulation of cyclase activity is conserved in these early forms of life. sAC is also expressed in other bicarbonate-responsive tissues, which suggests that bicarbonate regulation of cAMP signaling plays a fundamental role in many biological systems. 相似文献
93.
94.
Rienske AR Mortier Herman W Barkema Karin Orsel Robert Wolf Jeroen De Buck 《Veterinary research》2014,45(1):71
Although substantial fecal shedding is expected to start years after initial infection with Mycobacterium avium subspecies paratuberculosis (MAP), the potential for shedding by calves and therefore calf-to-calf transmission is underestimated in current Johne’s disease (JD) control programs. Shedding patterns were determined in this study in experimentally infected calves. Fifty calves were challenged at 2 weeks or at 3, 6, 9 or 12 months of age (6 calves served as a control group). In each age group, 5 calves were inoculated with a low and 5 with a high dose of MAP. Fecal culture was performed monthly until necropsy at 17 months of age. Overall, 61% of inoculated calves, representing all age and dose groups, shed MAP in their feces at least once during the follow-up period. Although most calves shed sporadically, 4 calves in the 2-week and 3-month high dose groups shed at every sampling. In general, shedding peaked 2 months after inoculation. Calves inoculated at 2 weeks or 3 months with a high dose of MAP shed more frequently than those inoculated with a low dose. Calves shedding frequently had more culture-positive tissue locations and more severe gross and histological lesions at necropsy. In conclusion, calves inoculated up to 1 year of age shed MAP in their feces shortly after inoculation. Consequently, there is potential for MAP transfer between calves (especially if they are group housed) and therefore, JD control programs should consider young calves as a source of infection. 相似文献
95.
96.
97.
Tesh M. Smalle Marthinus J. Hartman Lynette Bester Roxanne K. Buck Geoffrey T. Fosgate Gareth E. Zeiler 《Veterinary anaesthesia and analgesia》2017,44(3):427-434
Objective
To compare the effects of thiopentone, propofol and alfaxalone on arytenoid cartilage motion and establish the dose rates to achieve a consistent oral laryngoscopy examination.Study design
Randomised crossover study.Animals
Six healthy adult Beagle dogs.Methods
Each dog was randomly administered three induction agents with a 1-week washout period between treatments. Thiopentone (7.5 mg kg?1), propofol (3 mg kg?1) or alfaxalone (1.5 mg kg?1) was administered over 1 minute for induction of anaesthesia. If the dog was deemed inadequately anaesthetised, then supplemental boluses of 1.8, 0.75 and 0.4 mg kg?1 were administered, respectively. Continual examination of the larynx, using a laryngoscope, commenced once an adequate anaesthetic depth was reached until examination end point. The number of arytenoid motions and vital breaths were counted during three time periods and compared over time and among treatments. Data were analysed using Friedman and Mann–Whitney U tests, Spearman rho and a linear mixed model with post hoc pairwise comparison with Tukey correction.Results
The median (range) induction and examination times were 2.8 (2.0–3.0), 2.7 (2.0–3.3) and 2.5 (1.7–3.3) minutes (p = 0.727); and 14.1 (8.0–41.8), 5.4 (3.3–14.8) and 8.5 (3.8–31.6) minutes (p = 0.016) for thiopentone, propofol and alfaxalone, respectively. The median dose rates required to achieve an adequate anaesthetic depth were 6.3 (6.0–6.6), 2.4 (2.4–2.4) and 1.2 (1.2–1.2) mg kg?1 minute?1, respectively. There was no significant difference for the total number of arytenoid motions (p = 0.662) or vital breaths (p = 0.789) among induction agents.Conclusion and clinical relevance
The number of arytenoid motions were similar among the induction agents. However, at the dose rates used in this study, propofol provided adequate conditions for evaluation of the larynx with a shorter examination time which may be advantageous during laryngoscopy in dogs. 相似文献98.
The feeding of ethylenediamine dihydriodide (EDDI) at the dose levels of 50 and 500 mg/animal/day and urea at the dose level of 45 g/animal/day did not affect duration of clinical signs, body weight gain, magnitude or duration of fever, serum concentration of glutamic oxalacetic transaminase, packed cell volume, and differential white blood cell counts in feeder cattle experimentally infected with infectious bovine rhinotracheitis (IBR) virus. However, coughing and abundance of nasal discharge were significantly greater in calves fed EDDI before and during primary IBR virus infection. Those calves fed 500 mg of EDDI/day coughed more, had greater nasal discharge, and exhibited greater lacrimation than did those given the smaller dose. These 3 clinical signs were considered to reflect both the expectorant action of EDDI and the pathogenic effects of IBR virus. In all calves, including controls, the coughing, nasal discharge, and lacrimation were most prominent during the period of peak infection (7 to 14 days after the calves were given intranasal inoculation) of the IBR virus. Total serum iodine concentration became maximal (mean of 1,400 ng/ml) in 8 calves after they had been fed the larger dose of EDDI for 2 weeks. This value was maximal (about 300 ng/ml) in another 8 calves after 3 weeks' feeding of the smaller dose (50 mg/day). When EDDI exposure was maintained at the dose level of 50 mg/day for 5 weeks longer, mean serum iodine values remained at about 275 ng/ml, and those of control calves averaged 140 ng/ml. 相似文献
99.
Sex-related reduced weight gains in growing swine fed diets containing deoxynivalenol 总被引:1,自引:0,他引:1
L M Cote V R Beasley P M Bratich S P Swanson H L Shivaprasad W B Buck 《Journal of animal science》1985,61(4):942-950
A 5-wk feeding trial was conducted with 30 castrated male and 28 female, 5-wk-old crossbred piglets. Three different deoxynivalenol (DON) and zearalenone (Z)-contaminated diets were fed: .7, 3.1 and 5.8 ppm DON and 0, .05, and .1 ppm Z, respectively. The animals were fed their respective diets for 4 wk followed by the .7:0-ppm diet during wk 5. Feed intake and weight gain varied in a manner reciprocal to the levels of DON-Z in the diets during the first 4 wk (P less than .05). The castrated males had an overall lower weight gain compared with the females receiving the same diet (P less than .05). Gross postmortem changes were not different in either sex and tended to be most prominent in the pigs fed the lower DON:Z-contaminated diets after the first week, although they were seen in pigs fed the higher DON:Z diets after 4 wk of feeding. Lesions included mild to moderated reddening of the fundic mucosa of the stomach, reddening of the mucosa of the small intestine, and mild to moderate enlargement and edema of the mesenteric lymph nodes. Similarly, the severity of histologic changes tended to vary inversely with the concentrations of DON:Z in the diets after the first week but varied with the concentrations of DON:Z after 4 wk. They consisted of vascular congestion with mild to moderate multifocal erosions and degeneration of the mucosa in the stomach and small intestine. Mild to moderate lymphoid degeneration and depletion were also observed in the Peyer's patches of the intestines, bronchial and mesenteric lymph nodes, spleen, tonsil and thymus.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
100.
Abrahamsen MS Templeton TJ Enomoto S Abrahante JE Zhu G Lancto CA Deng M Liu C Widmer G Tzipori S Buck GA Xu P Bankier AT Dear PH Konfortov BA Spriggs HF Iyer L Anantharaman V Aravind L Kapur V 《Science (New York, N.Y.)》2004,304(5669):441-445
The apicomplexan Cryptosporidium parvum is an intestinal parasite that affects healthy humans and animals, and causes an unrelenting infection in immunocompromised individuals such as AIDS patients. We report the complete genome sequence of C. parvum, type II isolate. Genome analysis identifies extremely streamlined metabolic pathways and a reliance on the host for nutrients. In contrast to Plasmodium and Toxoplasma, the parasite lacks an apicoplast and its genome, and possesses a degenerate mitochondrion that has lost its genome. Several novel classes of cell-surface and secreted proteins with a potential role in host interactions and pathogenesis were also detected. Elucidation of the core metabolism, including enzymes with high similarities to bacterial and plant counterparts, opens new avenues for drug development. 相似文献