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101.
John R. Middleton Lisa Katz John A. Angelos Jeff W. Tyler 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1997,11(6):382-384
A 4-month-old, 6.8-kg, castrated male pygmy goat was examined for recurrent episodic fever and red urine of 7 days' duration. A second, 3-month-old, 7-kg, intact female pygmy goat was presented for similar clinical signs. The red discoloration of the urine in each case was determined to be due to hemolysis with subsequent hemoglobinuria. In both cases, hemolysis and hemoglobinuria were closely associated with the goats consuming large volumes of water from a human infant's nipple bottle. A diagnosis of water intoxication-induced hemolysis and hemoglobinuria was made. Episodes of hemoglobinuria in the first case were consistently associated with dilute (specific gravity < 1.010) urine. Water intoxication has been associated with bottle-feeding in human infants and is also widely reported in human psychiatric patients. The small erythrocytes in goats appear to be the most sensitive of the domestic species to hypotonicity-induced hemolysis. 相似文献
102.
Direct competitive enzyme-linked immunosorbent assay for sulfamethazine residues in milk 总被引:1,自引:0,他引:1
D E Dixon-Holland S E Katz 《Journal of the Association of Official Analytical Chemists》1989,72(3):447-450
A direct competitive enzyme-linked immunosorbent assay (ELISA) is described for the detection and estimation of sulfamethazine residues in milk. Samples are cleaned up rapidly by acidifying and centrifuging the milk, adjusting the supernatant liquid to pH 7.0, and centrifuging again. The supernate is then assayed using set points to estimate sulfamethazine levels in the sample in the range of 1 ppb to 1 ppm. Multiple samples of milk can be screened in 1.5-2 h by this ELISA method. 相似文献
103.
C J Singer S E Katz 《Journal of the Association of Official Analytical Chemists》1985,68(5):1037-1041
Procedures for the assay of chloramphenicol in milk, urine, serum, and muscle tissue are presented. The procedures specify an assay design with all standards as well as samples present on each plate, oxytetracycline in the buffer-diluent for greater sensitivity, a minimal medium to enhance the inhibitory effect of chloramphenicol on the assay organism, and a tetrazolium dye to improve the ability to measure the zones of inhibition. Recoveries of unbound chloramphenicol from bovine urine were 90.8%, from serum 88.3%, from milk 79.3%, from swine muscle 71.3%, and from beef and chicken muscle 61.0 and 61.4%, respectively. The lower levels of measurement in urine and serum were 0.25 microgram/mL, 0.025 microgram/mL in milk, and 0.10 microgram/g in muscle tissue. 相似文献
104.
105.
106.
Tumpey TM Maines TR Van Hoeven N Glaser L Solórzano A Pappas C Cox NJ Swayne DE Palese P Katz JM García-Sastre A 《Science (New York, N.Y.)》2007,315(5812):655-659
The 1918 influenza pandemic was a catastrophic series of virus outbreaks that spread across the globe. Here, we show that only a modest change in the 1918 influenza hemagglutinin receptor binding site alters the transmissibility of this pandemic virus. Two amino acid mutations that cause a switch in receptor binding preference from the human alpha-2,6 to the avian alpha-2,3 sialic acid resulted in a virus incapable of respiratory droplet transmission between ferrets but that maintained its lethality and replication efficiency in the upper respiratory tract. Furthermore, poor transmission of a 1918 virus with dual alpha-2,6 and alpha-2,3 specificity suggests that a predominant human alpha-2,6 sialic acid binding preference is essential for optimal transmission of this pandemic virus. These findings confirm an essential role of hemagglutinin receptor specificity for the transmission of influenza viruses among mammals. 相似文献
107.
The thiophene oligomer alpha-hexathienylene (alpha-6T) has been successfully used as the active semiconducting material in thin-film transistors. Field-induced conductivity in thin-film transistors with alpha-6T active layers occurs only near the interfacial plane, whereas the residual conductivity caused by unintentional doping scales with the thickness of the layer. The two-dimensional nature of the field-induced conductivity is due not to any anisotropy in transport with respect to any molecular axis but to interface effects. Optimized methods of device fabrication have resulted in high field-effect mobilities and on/off current ratios of > 10(6). The current densities and switching speeds are good enough to allow consideration of these devices in practical large-area electronic circuits. 相似文献
108.
109.
Tumlinson J Thom C Werk JK Prochaska JX Tripp TM Weinberg DH Peeples MS O'Meara JM Oppenheimer BD Meiring JD Katz NS Davé R Ford AB Sembach KR 《Science (New York, N.Y.)》2011,334(6058):948-952
The circumgalactic medium (CGM) is fed by galaxy outflows and accretion of intergalactic gas, but its mass, heavy element enrichment, and relation to galaxy properties are poorly constrained by observations. In a survey of the outskirts of 42 galaxies with the Cosmic Origins Spectrograph onboard the Hubble Space Telescope, we detected ubiquitous, large (150-kiloparsec) halos of ionized oxygen surrounding star-forming galaxies; we found much less ionized oxygen around galaxies with little or no star formation. This ionized CGM contains a substantial mass of heavy elements and gas, perhaps far exceeding the reservoirs of gas in the galaxies themselves. Our data indicate that it is a basic component of nearly all star-forming galaxies that is removed or transformed during the quenching of star formation and the transition to passive evolution. 相似文献
110.
The tropopause has been detected by ultrasensitive, narrow-beam, microwave (10.7-centimeter) and ultrahigh-frequency (71.5-cm) radars. Its reflectivity is consistent with that expected theoretically for a refractively turbulent medium. Indications are that the layer is also mechanically turbulent, and that electromagnetic scatter techniques may be used to detect high-altitude clear-air turbulence. 相似文献