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61.
W. J. Bruce 《The Journal of small animal practice》1998,39(7):333-340
Multiple ligamentous injuries of the canine stifle are uncommon. In this study, they affected mainly adult, male, working or sporting dogs and occurred secondary to severe trauma, or where chronic joint infection had weakened the supporting structures. Rupture of the cranial cruciate, caudal cruciate and lateral collateral ligaments was the most common injury observed and this occurred after catching the limb in a fence or gate. Reconstruction of the collateral and cranial cruciate ligaments, and careful repair of damaged menisci and joint capsule, was an effective method of treatment for medium- and large-size dogs. Reconstruction of the caudal cruciate ligament and postoperative limb support was not found to be essential. All dogs with subluxated stifles had good to excellent limb function with minimal loss of mid-thigh circumference or stifle joint range of motion at follow-up. Less favourable results were achieved where there was stifle joint luxation with extensive disruption to secondary joint restraints. 相似文献
62.
A Syndrome Resembling Idiopathic Noncirrhotic Portal Hypertension in 4 Young Doberman Pinschers 总被引:1,自引:0,他引:1
JoAnn DeMarco Sharon A. Center Nathan Dykes Amy E. Yeager Bruce Kornreich Ed Gschrey Kelly A. Credille Magali Guffroy Fabio del Piero Beth A. Valentine 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1998,12(3):147-156
We describe 4 young male Doberman Pinschers (3 littermates and 1 unrelated dog) with a syndrome resembling idiopathic or noncirrhotic portal hypertension of humans. Each dog was evaluated for a hepatopathy resulting in portal hypertension, development of portosystemic collateral vessels, and hepatic encephalopathy. These dogs differ from previous reports of young dogs with hepatic insufficiency associated with portal hypertension and acquired portal systemic shunting by their lack of intrahepatic arteriovenous fistulae, portal vein atresia, or intrahepatic fibrosis. Clinicopathologic features included erythrocyte microcytosis, normal to mildly increased liver enzyme activities, increased concentrations of serum bile acids, reduced plasma indocyanine green clearance, and normal total bilirubin concentration. Abdominal ultrasonography disclosed a small liver and portosystemic collateral vessels. Radiographic imaging studies confirmed hepatofugal portal circulation and discounted hepatic arteriovenous fistulae. Histopathologic features in liver tissue from each dog were similar and consistent in all sections examined. Common findings included increased cross-sectional views of hepatic arterioles; hepatic lobular atrophy; scanty increase in connective tissue around some large portal triads; and absence of inflammation, disturbed lobular architecture, bile duct proliferation, or intrahepatic cholestasis. 相似文献
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66.
Kathleen E. Rodgers Marcia H. Grayson Toshiko Imamura Bruce H. Devens 《Pesticide biochemistry and physiology》1985,24(2):260-266
Oral administration of O,O,S-trimethyl phosphorothioate (OOS), an impurity present in technical formulations of malathion, has been shown to be associated with a high incidence of pneumonia in rats and to be highly immunosuppressive in mice. Based on these findings, an in vitro model was established to study the effect of this and other organophosphorus compounds on murine cytotoxic T-lymphocyte (CTL) responses. The organophosphorus compounds were tested for their ability to block in vitro generation of CTL responses to alloantigen and/or the expression of these cytotoxic responses. Responses were generated in C57Bl/6 (H-2b) spleen cells to mitomycin C-blocked P815 (H-2d) tumor cells. The cytotoxicity of the cultured splenocytes to P815 target was measured using a 4-hr chromium release assay. These data demonstrated that malathion was able to block the ability of splenocytes to sensitize to P815 at concentrations as low as 25 μg/ml, but was not able to block the expression of cytotoxicity by mature killer T cells. The same was true for OOS which had been activated by preincubation with rat liver postmitochondrial supernatant (PMS). Activated OOS blocked the generation of CTL responses at concentrations as low as 75 μg/ml while having no effect on mature cytotoxic cells. In fact, both malathion and activated OOS were no longer able to suppress CTL responses if treatment was performed as early as 24 hr after exposure to antigen. Additionally, it was demonstrated that when malathion was preincubated with PMS it was no longer suppressive and that OOS without activation failed to suppress CTL responses. 相似文献
67.
Brenda S. Phillips Susan A. Kraegel Eric Simonson Bruce R. Madewell 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1998,12(3):171-172
During a 4-month period, 34 dogs with tumors received a total of 60 doses of a single generic formulation of doxorubicin; 13 acute drug reactions were observed in these 34 dogs, and no acute reactions were observed after replacing the product with the proprietary brand. These reactions were characterized by one or more of the following signs: pruritus; head-shaking; urticaria; erythema of the pinnal, axillary, or inguinal regions; vocalization; vomiting; hyperemic or pale mucous membranes; high heart rate; and high respiratory rate. We propose that a component unique to generic doxorubicin was responsible for the unusually high number of acute drug reactions observed. 相似文献
68.
The authors visited some deer farms in Northeastern China in 1991 and 1993. The seven subspecies of Asian Wapiti (Cervus elaphus) were detected by observing the animal’s appearance and analyzing the video information. The status of taxonomy research
in China was also discussed. 相似文献
69.
Traditionally, poplars (Populus) have been planted to control erosion on New Zealand's hill-slopes, because of their capacity to dry out and bind together the soil, by reducing effective rainfall and increasing evapotranspiration and soil strength. However, the effect of widely spaced poplars on the partitioning of soil water and rainfall has not been reported. This study determined rainfall partitioning for 18 mid-spring days in a mature P. deltoides (Bart. ex Marsh, Clone I78)-pasture association (37 stems per hectare, unevenly spaced at 16.4 +/- 0.4 m) and compared it with a traditional open pasture system in grazed areas of a hill environment. Tree transpiration was measured by the heat pulse technique. A time-driven mathematical model was used to set a zero offset, adjust anomalous values and describe simultaneous sap velocity time courses of trees. The model showed that daylight sap flow velocities can be represented with a nonlinear Beta function (R(2) > 0.98), and differences in the parameters representing the initiation, duration and conformation of the sap velocity can be tested statistically to discern tree transpiration differences during the day. Evapotranspiration was greater for the poplar-pasture association than for the open pasture (2.7-3.0 versus 2.2 mm day(-1)). The tree canopy alone contributed 0.92 mm day(-1) as transpiration and 1.37 mm day(-1) as interception, whereas evapotranspiration of the pasture understory was only 0.4-0.6 mm day(-1). Despite the higher water use of the poplar-pasture association, soil water in the 0-300 mm soil stratum was higher than, or similar to, that of the open pasture. Tree shading decreased evapotranspiration and pasture accumulation under the trees. 相似文献
70.
Assessment of allometric algorithms for estimating leaf biomass, leaf area index and litter fall in different-aged Sitka spruce forests 总被引:1,自引:0,他引:1
Tobin Brian; Black Kevin; Osborne Bruce; Reidy Brian; Bolger Tom; Nieuwenhuis Maarten 《Forestry》2006,79(4):453-465
The relationship between leaf area and diameter at breast height(d.b.h.) or sapwood area (AS) has been used to estimate standleaf area or biomass of forest canopies. It has been suggestedthat intra-specific variations in the relationship between standleaf area and d.b.h. or AS can introduce a systematic errorin these estimates for younger and older stands unless additionalparameters relating to canopy structure are included in allometricfunctions. We collected data from a Sitka spruce chronosequenceto parametrize and test different algorithms for the estimationof foliar biomass (FB) and litter inputs over a range of forestages. FB estimates were significantly improved when additionalbiometric information relating to crown structure (canopy opennessand height of live crown) was included in the models. Althoughthe use of the relationship between leaf area and AS for theestimation of leaf area is justified by theoretical considerations(pipe model theory), we show that d.b.h. and other canopy parametersprovided the most robust estimation of leaf area across different-agedstands. Our results also suggest that the accuracy of litterinput estimates depends on needle retention time and annualturnover rate, particularly immediately before and after canopyclosure. 相似文献