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81.
82.
Isolates ofPhytophthora infestans collected in Canada from potato and tomato plants from 1994 to 1998 were tested for their responsein vitro to equal active ingredient concentrations (1, 2.5, and 5 μg a.i/mL) of six commercial fungicides: Acrobat MZ (dimethomorph and mancozeb), Ridomil Gold (metalaxyl-m), Dithane (mancozeb), Curzate (cymoxanil), Bravo (chlorothalonil), and Tattoo C (propamocarb and chlorothalonil). Relative mycelial growth of isolates estimated on fungicideamended vs fungicide-free media was compared among isolates of the US-8 and US-11 genotypes from the two host plants. The effects of these fungicides on spore germination of isolates from the two genotypes were also estimated. Mycelial growth of US-8 and US-11 isolates was most affected by Bravo and Tattoo C, followed by Acrobat, and then Curzate and Dithane. Ridomil Gold was not effective in inhibitingin vitro growth of US-11 isolates at the concentrations tested. Variations in sensitivity to different fungicides among isolates of the same genotype collected in different years were observed. For example, based on 2.5 and 5 μg a.i./mL, potato/US-11 isolates collected from 1995 to 1997 showed increased sensitivity to Curzate and Ridomil Gold, while decreased sensitivity was recorded with Dithane. For US-8 isolates, responses to the fungicides varied according to fungicide and year. Variations were generally not significant for Acrobat, Curzate, Bravo, and Tattoo C over time. Conversely, potato/US-8 isolates from 1995 and 1998 were less sensitive to Dithane and Ridomil Gold than those from 1994, 1996, and 1997. 相似文献
83.
A series of new metallized direct dyes based on benzidine congeners, 2,2′-dimethyl-5,5′-dipropoxybenzidine and 5,5′-dipropoxybenzidine,
were evaluated for mutagenicity in Salmonella typhimurium strains TA98 and TA100. All of the dyes examined were judged to
be non-mutagenic with and without metabolic activation while toxicity was seen in some dyes at high doses. The study also
suggested that the standard Salmonella mutagenicity plate-incorporated assay was an excellent method for evaluation of dyes
for mutagenicity. 相似文献
84.
Physicochemical properties of mixtures of native potato and native amaranth (Amaranthus cruentus), heat‐moisture treated (HMT) potato and heat‐moisture treated amaranth, cross‐linked potato and cross‐linked amaranth, native potato and heat‐moisture treated amaranth, and heat‐moisture treated potato, and native amaranth were tested at different ratios. Two peaks were noticed in the pasting curves when large differences of swelling factor and amylose leaching existed between individual components in the mixture. It seems that amylose leaching from one starch in a mixture may affect the swelling and much of the granular break down of the other. The mixtures showed stabilities in hot pastes that were higher than the less stable components in a mixture. Some mixtures such as HMT potato and native amaranth showed very specific nonadditive pasting behavior. Mixing 10% of native amaranth to HMT potato starch caused a large reduction of peak viscosity and cold paste viscosity, resulting in a very soft gel. In the differential scanning calorimeter, each component of a mixture gelatinized independently, showing two peaks corresponding to the individual components. When transition temperatures of both components were similar in DSC, the result was a single endotherm. Dramatic changes of pasting and subsequent gel properties resulted when thermal transition of the two components occurred in the same temperature range. Retrogradation enthalpies as measured by DSC were between the two individual components in all tested mixtures. 相似文献
85.
Kevin T. Corley BSc BVMSm PhD MRCVS Harold C. McKenzie III DVM MS Lisa M. Amoroso DVM Martin O. Furr DVM DACVIM 《Journal of Veterinary Emergency and Critical Care》2000,10(4):267-276
Seven critically ill foals that continued to be hypotensive despite fluid resuscitation and the infusion of dobutamine and/or dopamine were treated with an infusion of norepinephrine (noradrenaline). The norepinephrine was administered concurrently with dobutamine, and the combination therapy was titrated by use of indirect mean arterial pressure measurements. The highest dose of norepinephrine used was 1.5 mcg/kg/min. In six foals the administration of norepinephrine was associated with an increase in blood pressure. In one foal the mean arterial pressure did not increase in response to the doses of norepinephrine administered. All of the foals experienced an increase in urine output coincident with the start of the norepinephrine infusion. Three of the foal survived to hospital discharge. 相似文献
86.
The effect of betacyanin pigments from Amaranthus tricolor and Amaranthus cruentus on chromatic and physicochemical properties of three wheat flours was studied. Addition of Amaranthus betacyanins increased the gelatinization temperatures (T(o), T(p), and T(c)) of all wheat flours without altering their transition ranges (T(c)-T(o)). The melting enthalpies (DeltaH) were either increased or decreased depending on the types of flour and pigment. Amaranthus betacyanins decreased the peak viscosity (PV), hot paste viscosity (HPV), cold paste viscosity (CPV), setback (SB), and pasting time (PT) of all flours and increased the breakdown (BD). Texture profile analysis (TPA) showed that Amaranthus betacyanins decreased hardness, and gumminess, and increased cohesiveness of all gels, without altering adhesiveness. Chromatic investigation exhibited that A. tricolor and A. cruentus pigments imparted gels with red and orange-yellow hues with favorable color stability. 相似文献
87.
Purpose The goal of our study was the evaluation of a practical method for the recording of flash electroretinograms (ERGs) in sedated, standing horses with the DTL? microfiber electrode. Methods The horses were sedated intravenously with detomidine hydrochloride (0.015 mg/kg). The pupil was dilated and the auriculopalpebral nerve was blocked. The ERGs were recorded with the active electrode on the cornea (DTL?), the reference electrode near the lateral canthus, and the ground electrode over the occipital bone. The light intensities of the white strobe light were 0.03 cd·s/m2 (scotopic) and 3 cd·s/m2 (scotopic and photopic). Photopic and scotopic single flash and flicker responses to Ganzfeld stimulation were recorded. During the 20‐min dark adaptation period the retina was stimulated every 5 min with the 0.03 cd·s/m2 single flash. Results The median b‐wave amplitudes and implicit times were 38 µV and 33 ms (photopic cone‐dominated response), 43 µV and 63 ms (5‐min dark adaptation), 72 µV and 89 ms (10 min), 147 µV and 103 ms (15 min), 188 µV and 109 ms (20 min, 0.03 cd·s/m2, rod response), and 186 µV and 77 ms (20 min, 3 cd·s/m2, maximal combined rod‐cone response). A steady increase in amplitude and implicit time was noted during dark adaptation. No oscillatory potentials could be isolated. Conclusions The use of detomidine hydrochloride sedation and the DTL? microfiber electrode allowed the recording of good quality ERGs. This protocol should permit the detection of functional problems in the retina without the risk involved with general anesthesia. 相似文献
88.
89.
90.
Joy E. Tomlinson Amit Kapoor Arvind Kumar Bud C. Tennant Melissa A. Laverack Laurie Beard Katie Delph Elizabeth Davis Harold Schott II Kara Lascola Todd C. Holbrook Philip Johnson Sandra D. Taylor Erica McKenzie Jessica Carter‐Arnold Emilie Setlakwe Lisa Fultz Jeff Brakenhoff Rebecca Ruby Sheetal Trivedi Gerlinde R. Van de Walle Randall W. Renshaw Edward J. Dubovi Thomas J. Divers 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2019,33(1):251-257