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981.
A 5-year-old, male German shepherd dog was evaluated for a 5-week history of vomiting, diarrhea, lethargy, and weight loss. In abdominal radiographs, there was an unusual corrugated appearance within a loop of intestine. Sonographically, this loop also had a similar corrugated appearance with alternating hyperechoic and hypoechoic bands. Lymph nodes within the abdomen and thorax were enlarged, and a thoracic mass was also detected. Ultrasound-guided fine-needle aspirates of the mesenteric lymph nodes were highly suggestive of lymphoma. After postmortem examination, a diagnosis of multicentric lymphoma with involvement of the gastrointestinal tract was made.  相似文献   
982.
983.
984.
The successful conservative treatment of an open, displaced fracture of the radius of a horse suggests that conservative treatment should not be ignored when surgery is not an option. The importance of proper soft-tissue management and the use of broad-spectrum antimicrobial treatment in the management of orthopedic injuries is emphasized.  相似文献   
985.
The acute single dose oral toxicity of carbophenothion (S-4-chlorophenylthiomethyl OO-diethyl phosphorodithioate) has been determined in Canada geese (Branta canadensis), pigeons (Columba livia) and Japanese quail (Coturnix coturnix japonica). At post mortem examination gross pathological changes were observed in Canada geese and pigeons and esterase levels were determined by conventional and electrophoretic methods on extracts of liver and brain from these two species. Carbophenothion residue levels were determined in liver, brain and gizzard contents from the geese and pigeons. The overall pattern of results suggests that esterase inhibition may not be the dominant factor in carbophenothion poisoning in geese. It is suggested that a brain carbophenothion residue level of 1 part/106 is indicative of death by poisoning in geese.  相似文献   
986.
The inhibition of eel acetylcholinesterase by the 4-nitrophenyl esters of 2-furyl(methyl)-, methyl(2-thienyl)-, di-2-furyl-, and di-2-thienylphosphinic acid (I, II, III, and IV, respectively) was investigated at pH 6.90 in 0.067 M phosphate buffer (25.0°C) using stopped-flow instrumentation and automated data processing. Our evaluation of the dissociation constant, Kd, the unimolecular bonding rate constant, k2, and the bimolecular reaction constant, ki, are the first reported values for these constants for alkyl/heteroaryl and diheteroaryl esters of phosphinic acids. The largest ki value (19,330 M?1 sec?1) was observed for the reaction of I with the enzyme. The order for the remaining three is II > IV > III. There is no direct relationship between the hydrolysis rates of the esters and their anticholinesterase activities on eel acetylcholinesterase. Likewise, there is no direct relationship between their anticholinesterase activities and the LD50 values in rats.  相似文献   
987.
Zusammenfassung Die Photosyntheserate blühender Gersten- und Weizenähren verschiedener Sorten wurden gemessen. Die Sorten unterschieden sich in Vorhandensein, Form und Größe der Grannen.Die Photosyntheseleistung ist bei den stark begrannten Formen am größten, am geringsten bei den unbegrannten. Die Werte für kurzgrannige Varietäten lagen dazwischen.
Summary The photosynthetic rate of flowering barley and wheat ears from different sorts was measured. The sorts differed in presence, form and size of awns.The intensity of photosynthesis was highest among the forms with long awns and lowest among the awnless sorts. The values of the short-awned varieties lay between them.

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Herrn Dr. Lehmann danken wir für die Unterstützung bei der Auswahl gegeigneter Formen und die Überlassung von Saatgut.  相似文献   
988.
Sheep were dosed orally with diazinon at 450 and 600 mg/kg: residues of diazinon were determined in the blood, brain, liver, kidney cortex and medulla, muscle, fat and rumen contents at intervals after dosing, and cholinesterase activities in the erythrocytes and the brain were determined at the same intervals. The relations between residues, cholinesterase activity and clinical symptoms are discussed from the points of view of their diagnostic value and the possibility of undesirable residues occurring in poisoned animals. Rough estimates of the residues of two metabolites, hydroxydiazinon and dehydro-diazinon, in one sheep are also discussed. The oxygen analogue of diazinon was not detected although it was specifically sought.  相似文献   
989.
Multiple hereditary ocular anomalies in a herd of cattle   总被引:1,自引:0,他引:1  
A Brahman x Santa Gertrudis herd of cows bred to a Hereford bull was evaluated because of a 3-year history of several calves born with congenital blindness. Multiple congenital ocular anomalies in 2 calves included microphthalmos, microcornea, microcoria, heterochromia iridis, microlentia, cataracts, retinal dysplasia, retinal detachment, anterior segment dysgenesis, acorea, and proliferation of the anterior neuroectoderm. On the basis of the lack of environmental factors and persistence of an intermittent problem when breeding to a single bull, a genetic defect was diagnosed as the probable cause. Dominant inheritance with varied expressivity may have best explained the lack of obvious signs in the bull, with emergence of various anterior and posterior segment defects in offspring from unrelated cows.  相似文献   
990.
The water extracted from casing layer and substrate by the fruit bodies of the first flush of a mushroom culture (Agaricus bisporus) was investigated. In cultures with a 5-cm casing layer, 33–34% of the water in the sporophores came from the casing, and the remainder from the substrate. In cultures with thin casing layers (3–3.5 cm), only 14–15% of the water came from the casing. Fruit bodies from thin layers contained less water than the ones from thicker layers. Fruit bodies from thick casing layers (6 cm) and harvested early took 36–37% of their water from the casing. Mushrooms from the late harvest (caps fully open) took 40–51% of their water from the casing layer and contained more water than early-harvested ones. The sporophores of the first flush extracted more water (g per g substrate) from the top third of the substrate than from the lower layers.  相似文献   
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