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71.
72.
Rectal transmission of bovine leukemia virus in cattle and sheep 总被引:2,自引:0,他引:2
Bovine leukemia virus (BLV) was transmitted by rectal inoculation of BLV-infective whole blood into cattle and sheep. Two cows and 2 sheep each were given 500 ml and 50 ml of blood, respectively, by rectal infusion. Two sheep which served as positive controls each were given 1 ml of the same blood, IV. All animals became seropositive to BLV by postinoculation week 5. Although relatively large volumes of blood were used for rectal inoculation, a base line for infectivity was established for the rectal route. 相似文献
73.
Henry Hägerstrand Mikael Himberg Erkki Jokikokko Mikael von Numers Lucyna Mrówczyńska Anti Vasemägi Tom Wiklund Jan‐Olof Lill 《Ecology of Freshwater Fish》2017,26(1):66-74
To investigate whether European whitefish (Coregonus lavaretus) groups in the brackish (≤7%) Gulf of Bothnia (Baltic Sea) express specific otolith elemental characteristics, concentrations of elements (Ca, Ba, Sr, Zn, Mn, Fe) in whole otoliths were studied by inductively coupled plasma‐optical emission spectrometry. Whitefish (N = 67) were sampled from six different latitudinal sites; four in the sea and two in rivers along the west coast of Finland, and from a fresh water lake for comparison. The concentration of several elements showed significant differences among sampling sites. Otolith Ba concentrations were higher at the northern sampling sites compared to the southern ones, thereby showing negative association to capture‐habitat salinity. In contrast, otolith Sr and Zn concentrations were lower at the northern sampling sites, thereby associating positively to capture‐habitat salinity. Otolith Mn concentrations did not associate with latitude or salinity but markedly varied between sampling sites. Elevated Fe concentrations occurred in fish otoliths from the two northernmost sites. Ca concentrations were at the same levels in otoliths from all whitefish samples. Otoliths of whitefish from the lake had very high Ba and low Sr concentrations compared to concentrations in otoliths from whitefish in the sea and rivers. Our results show that otolith elemental characteristics of whitefish vary considerably at various geographic scales showing high potential for population identification using elemental fingerprints. Analysis of otolith elemental characteristics may therefore provide an efficient tool for the identification of main areas of residence, spawning locations, and migration routes, thus contributing towards the sustainable management of whitefish stocks. 相似文献
74.
Price DC Chan CX Yoon HS Yang EC Qiu H Weber AP Schwacke R Gross J Blouin NA Lane C Reyes-Prieto A Durnford DG Neilson JA Lang BF Burger G Steiner JM Löffelhardt W Meuser JE Posewitz MC Ball S Arias MC Henrissat B Coutinho PM Rensing SA Symeonidi A Doddapaneni H Green BR Rajah VD Boore J Bhattacharya D 《Science (New York, N.Y.)》2012,335(6070):843-847
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Wahlen M Tanaka N Henry R Deck B Zeglen J Vogel JS Southon J Shemesh A Fairbanks R Broecker W 《Science (New York, N.Y.)》1989,245(4915):286-290
Measurements of carbon-14 in small samples of methane from major biogenic sources, from biomass burning, and in "clean air" samples from both the Northern and Southern hemispheres reveal that methane from ruminants contains contemporary carbon, whereas that from wetlands, pat bogs, rice fields, and tundra is somewhat, depleted in carbon-14. Atmospheric (14)GH(4) seems to have increased from 1986 to 1987, and levels at the end of 1987 were 123.3 +/- 0.8 percent modern carbon (pMC) in the Northern Hemisphere and 120.0 +/- 0.7 pMC in the Southern Hemisphere. Model calculations of source partitioning based on the carbon-14 data, CH(4) concentrations, and delta(13)C in CH(4) indicate that 21 +/- 3% of atmospheric CH(4) was derived from fossil carbon at the end of 1987. The data also indicate that pressurized water reactors are an increasingly important source of (14)CH(4). 相似文献
78.
James Cartwright Richard M. Green 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2010,39(3):354-357
Background: The enzyme 4‐hydroxyphenylpyruvate dioxygenase (HPPD) is key in tyrosine catabolism. Inhibition of HPPD results in tyrosinemia and increased urinary excretion of 3 phenylketones: 4‐hydroxyphenylpyruvate (HPPA), 4‐hydroxyphenyllactate (HPLA), and 4‐hydroxyphenylacetate (HPAA). A previous study involving administration of a novel HPPD inhibitor to dogs resulted in detection of ketonuria in treated animals using urine dipsticks read by reflectance photometry. Dipstick‐positive results were suspected to be false because high concentrations of urinary phenylketones have been reported to react with ketone test fields of urine dipsticks, but visual confirmation was not performed. Objective: The purpose of this study was to determine which of the 4‐hydroxyphenolic acids produced by HPPD inhibition react with ketone test fields of 3 commercially available urine dipsticks. Methods: Canine urine samples were prepared with HPPA, HPLA, HPAA, and lithium acetoacetate (positive control) at 6 concentrations. Unmodified urine samples were used as negative controls. All samples were tested for ketones using Combur 10 Test M dipsticks read by a Miditron dipstick analyzer. Urinalysis was also performed by visually inspecting ketone test fields on the Combur 10 Test M, Multistix 10 SG, and Aution 10 EA dipsticks. Results: Urine samples containing HPPA were positive for ketones with Combur 10 Test M dipsticks read by the Miditron analyzer and produced a red–brown color change in ketone test fields of all 3 dipsticks. Urine samples containing HPLA and HPAA were negative by all methods. Conclusion: The phenylketone HPPA reacts with ketone test fields of 3 commercially available urine dipsticks, producing a red–brown color change that may be misinterpreted as positive for ketones by reflectance photometry. 相似文献
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J P Hoover G A Henry R J Panciera 《Journal of the American Veterinary Medical Association》1992,201(4):599-602
Bronchial cartilage dysplasia is believed to have caused lobar bullous emphysema in a 5-month-old Chow Chow that had exercise intolerance, progressive dyspnea, and episodic cough. Radiography of the thorax revealed hyperlucency of the left hemithorax, displacement of the mediastinum and heart to the right, and flattening of the diaphragm. The pup died shortly after the radiographs were obtained. Necropsy revealed massive hyperinflation with 180 degrees torsion of the cranial portion of the left cranial lung lobe, and hyperinflation with less than 180 degrees torsion of the right accessory lung lobe. Histologic examination of the affected lung lobes revealed a lack of bronchial cartilage, loss and displacement of alveolar walls, and bulla formation that resembled congenital (infantile) lobar emphysema of human beings. In this pup, lung lobe torsions may have been predisposed by bronchial cartilage dysplasia. 相似文献