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991.
Quantitative hepatic scintigraphy is a noninvasive test for measurement of relative arterial and portal blood flow to the liver. This technique has been used to evaluate human patients with known or suspected liver tumors or diffuse hepatocellular disease. A computer program to assess the hepatic perfusion index (HPI) in the normal dog is described. Factors affecting study quality and accuracy include injection technique, cardiac function, patient position, respiration, gross patient motion, and user intervention during data processing. HPI for a group of 12 normal dogs was 0.9±0.4 (X±SD). Quantitative scintigraphy could be used to evaluate dogs with primary or secondary liver tumors, portacaval shunts, or chronic liver disease  相似文献   
992.
Blood samples and ticks were obtained from dogs to assess canine exposure to spotted fever-group (SFG) rickettsiae during 1978-1980 in southern Connecticut. Of the 1,576 dog sera screened by microimmunofluorescence. 174 (11.0%) contained specific antibodies at titers greater than or equal to 1:64 against Rickettsia montana (n = 34), R rickettsii (n = 31), R rhipicephali (n = 19), or the unclassified 369-C rickettsia (n = 90). End points greater than or equal to 1:8,192 to R rickettsii and to R rhipicephali were recorded for 6 and 3 sera, respectively. Seropositivity rates from southwestern and southeastern Connecticut were similar (about 11%), with positive sera obtained from each region in nearly all months of the investigation. Rates were between 10% for dogs 2 to 7 years old and 14% for those greater than or equal to 8 years. Eight of 629 Dermacentor variabilis, 1 of 18 Ixodes dammini, and 2 of 3 Amblyomma americanum were positive by direct immunofluorescence for SFG rickettsiae. Thirteen D variabilis contained unidentified, long, bacillus-like organisms that differed from the short, ovoid (coccal) forms typical fo the spotted-fever agent, R rickettsii. With the exposure to infected ticks and production of type-specific antibodies against at least 4 SFG antigens, dogs may serve as suitable enzootic or epizootic indicators of rickettsial activity.  相似文献   
993.
The activity of 12 herbicides was tested against various freshwater algae found in Britain. Three of the most troublesome species, Cladophora glomerata L., Rhizoclonium hieroglyphicum Katz., and Vaucheria dichotoma Ag. were all susceptible to methylthio-1,3,5-triazines. Terbutryne and cyanatryn were the most active and both killed C. glomerata and R. hieroglyphicum at 0.05 mg/litre. The concentration of terbutryne had to be increased to 0.1 mg/litre to control V. dichotoma. Asulam and WSCP (2.0 mg/litre), metflurazone and HZ5914 (1.0 mg/litre), copper sulphate (1.0 mg copper ion/litre) and cutrine (2.0 mg copper ion/litre) had no visible effect on the algae. Diquat (1.0 mg cation/litre) did, however, control C. glomerata and R. hieroglyphicum although, in natural conditions, the algae quickly recovered after treatment. Success with diquat (2.0 mg/litre) against V. dichotoma in laboratory experiments was not achieved in a field experiment.  相似文献   
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An attempt has been made to design a herbicide by synthesising active site directed irreversible inhibitors for the peroxidase-catalysed oxidation of indolyl-3-acetic acid (IAA). A variety of substituted indoles were prepared and found to bind reversibly to the enzyme, but none produced any progressive inhibition, nor showed any herbicidal activity. This may be related to the fact that the inhibitors can be degraded by peroxidase in vitro since, if this occurred in the plant, the compounds could not then interfere with IAA oxidation.  相似文献   
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Objective-To determine the outcome of penetrating injuries to the central region of the foot in equids and identify factors that may affect treatment and outcome. Design-Retrospective case series. Animals-63 equids (61 horses, 1 pony, and 1 mule). Procedures-Records of equids incurring puncture wounds through the frog (cuneus ungulae) or collateral sulci of the foot between 1998 and 2008 were reviewed. Evaluated factors that were hypothesized to affect outcome included signalment, degree of lameness, foot affected, duration between injury and admission, and treatment. Injuries were graded from 1 (< 1 inch; involving superficial corium only) to 4 (involving a synovial structure) on the basis of severity of penetration as determined by radiographic evidence or findings on synoviocentesis at the time of admission. Results-Overall, 60% (38/63) of equids returned to soundness. Thirteen equids were euthanized on the basis of synovial structure involvement and financial constraints. Of 35 equids that were treated conservatively, which may have included undergoing a surgical procedure with the horse standing, 32 (91.4%) returned to their previous level of soundness. Fifteen equids underwent surgical treatment under general anesthesia, of which 6 (40%) became sound for intended use. Ten of 34 (29%) equids with synovial structure involvement regained soundness. Equids treated earlier after injury had a better prognosis. Equids with a hind foot injury had a more favorable outcome than those with a forefoot injury. Conclusions and Clinical Relevance-Results suggested that penetrating injuries located centrally in the foot of equids without involvement of a synovial structure have a favorable prognosis, especially if managed early. Penetration of a synovial structure provided a poor prognosis.  相似文献   
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