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91.
Objective To report the occurrence of Myxobolus episquamalis in sea mullet, Mugil cephalus L , caught in estuaries in eastern and western Australia.
Design A prospective study of commercial catches of mullet in the Clarence River of NSW and individual cases from other areas.
Results The organism caused pale, white to pink, raised lesions on the scales and fins of sea mullet. Occurrence of infection was highest in spring and in a marine (down-river) environment compared to a brackish environment. Up to 6% of fish were affected in commercial catches.
Conclusion The infection is widespread in Australian mullet, but rarely causes significant economic loss.  相似文献   
92.
Confirmed histoplasmosis in an Australian dog   总被引:1,自引:0,他引:1  
  相似文献   
93.
94.
Ivermectin injectable solution (1% w/v) was highly effective against Sarcoptes scabiei var suis when administered subcutaneously once to swine at 300 mcg/kg body weight. There were significantly (P < 0.05) fewer Sarcoptes mange mites counted on pigs treated with ivermectin than on untreated pigs at each count up to day 56 after treatment. The results indicate ivermectin should provide an efficient, practical means of control of sarcoptic mange in intensive piggeries.  相似文献   
95.
Gamma-ray burst (GRB) afterglows have provided important clues to the nature of these massive explosive events, providing direct information on the nearby environment and indirect information on the central engine that powers the burst. We report the discovery of two bright x-ray flares in GRB afterglows, including a giant flare comparable in total energy to the burst itself, each peaking minutes after the burst. These strong, rapid x-ray flares imply that the central engines of the bursts have long periods of activity, with strong internal shocks continuing for hundreds of seconds after the gamma-ray emission has ended.  相似文献   
96.
Modifying electrical activation conditions have been used to improve in vitro embryo production and development in pigs. However, there is insufficient information about correlations of porcine embryo development with oocyte pre‐ and post‐activation conditions. The purpose of this study was to compare the developmental rates of porcine oocytes subjected to different mannitol exposure times, either pre‐ or post‐electrical activation, and to elucidate the reason for the optimal mannitol exposure time. Mannitol exposure times around activation were adjusted as 0, 1, 2 or 3 min. Blastocyst development were checked on day 7. Exposure of oocytes to mannitol for 1 or 2 min before electrical activation produced significantly higher blastocyst rates than exposure for 0 or 3 min. There was no significant difference in blastocyst rates when activated oocytes were exposed to mannitol for 0, 1, 2 or 3 min after electrical activation. While exposure of oocytes to mannitol for 1 min pre‐ and 3 min post‐activation showed significantly higher blastocyst development than 0 min pre‐ and 0 min post‐activation. It also showed higher maintenance of normal oocyte morphology than exposure for 0 min pre‐ and 0 min post‐activation. In conclusion, exposure of oocytes to mannitol for 1 min pre‐ and 3 min post‐activation seems to be optimal for producing higher in vitro blastocyst development of porcine parthenogenetic embryos. The higher blastocyst development is correlated with higher maintenance of normal morphology in oocytes exposed to mannitol for 1 min pre‐ and 3 min post‐activation.  相似文献   
97.
The effects of estradiol, insulin, and gonadotropins on levels of insulin-like growth factor binding protein (IGFBP)-2, -3, -4, and -5 mRNA levels in bovine granulosa and theca cells were evaluated in vitro using serum-free medium containing various hormone treatments arranged in four different experiments. Amounts of IGFBP-2, -3, -4 and -5 mRNA were quantitated using fluorescent quantitative real-time RT-PCR. In small-follicle (1-5 mm) granulosa cells, follicle-stimulating hormone (FSH) in the presence or absence of insulin increased (P<0.05) IGFBP-3 mRNA but did not change IGFBP-2, -4, or -5 mRNA levels; estradiol was without effect on IGFBP-2, -3, -4, or -5 mRNA levels in the absence of insulin but increased (P<0.05) IGFBP-2 mRNA levels in the presence of insulin. Luteinizing hormone (LH) in the absence (but not presence) of insulin increased (P<0.05) small-follicle granulosa cell IGFBP-3 mRNA levels. In large-follicle (>7.9 mm) granulosa cells, insulin alone increased (P<0.05) IGFBP-2 gene expression while LH, FSH, and estradiol were without effect (P>0.10). Estradiol (3 and 300 ng/ml) decreased (P<0.05) IGFBP-5 mRNA levels in large-follicle granulosa cells. In theca cells, insulin decreased (P<0.05) IGFBP-4 expression, but had no effect (P>0.10) on IGFBP-2, -3, or -5 mRNA levels. Estradiol decreased (P<0.05) IGFBP-2, -3, and -4 mRNA levels but had no effect on IGFBP-5 mRNA levels in theca cells. LH had no effect on levels of IGFBP-2, -3, -4, or -5 mRNA in theca cells. These results indicate that expression of IGFBP-2, -3, -4, and -5 mRNA by granulosa and theca cells are differentially regulated by estradiol, insulin and gonadotropins, therefore discretely modulating the amount of bioavailable IGFs to these cells depending upon the specific hormonal stimuli. In particular, these studies are the first in cattle to show that estradiol selectively inhibits IGFBP-2, -3, and -4 gene expression in theca cells, inhibits IGFBP-5 gene expression in large-follicle granulosa cells, and stimulates IGFBP-2 gene expression in small-follicle granulosa cells.  相似文献   
98.
Gold nanoelectrodes of varied size: transition to molecule-like charging   总被引:1,自引:0,他引:1  
A transition from metal-like double-layer capacitive charging to redox-like charging was observed in electrochemical ensemble Coulomb staircase experiments on solutions of gold nanoparticles of varied core size. The monodisperse gold nanoparticles are stabilized by short-chain alkanethiolate monolayers and have 8 to 38 kilodaltons core mass (1.1 to 1.9 nanometers in diameter). Larger cores display Coulomb staircase responses consistent with double-layer charging of metal-electrolyte interfaces, whereas smaller core nanoparticles exhibit redox chemical character, including a large central gap. The change in behavior is consistent with new near-infrared spectroscopic data showing an emerging gap between the highest occupied and lowest unoccupied orbitals of 0.4 to 0.9 electron volt.  相似文献   
99.
Integrating conceptually similar models of the growth of marine and terrestrial primary producers yielded an estimated global net primary production (NPP) of 104.9 petagrams of carbon per year, with roughly equal contributions from land and oceans. Approaches based on satellite indices of absorbed solar radiation indicate marked heterogeneity in NPP for both land and oceans, reflecting the influence of physical and ecological processes. The spatial and temporal distributions of ocean NPP are consistent with primary limitation by light, nutrients, and temperature. On land, water limitation imposes additional constraints. On land and ocean, progressive changes in NPP can result in altered carbon storage, although contrasts in mechanisms of carbon storage and rates of organic matter turnover result in a range of relations between carbon storage and changes in NPP.  相似文献   
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