A revised concept of landscape equilibrium: Disturbance and stability on scaled landscapes   总被引：20，自引：0，他引：20  

Monica G. Turner  William H. Romme  Robert H. Gardner  Robert V. O'Neill  Timothy K. Kratz 《Landscape Ecology》1993,8(3):213-227

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Traumatic rupture of the urinary bladder in a horse     

C. BECK  AJ DART  SA McCLINTOCK  DR HODGSON 《Australian veterinary journal》1996,73(4):154-155

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A longitudinal study of lymphocyte subsets in a cohort of cats naturally-infected with feline immunodeficiency virus     

C. WALKER  PJ CANFFIELD†  DN LOVE†  DR McNEIL‡ 《Australian veterinary journal》1996,73(6):218-224

Despite the potential of feline immunodeficiency virus (FIV) as an animal model for human immunodeficiency virus (HIV) studies, the long term effects of naturally-occurring infection have not been determined. HIV infection causes an ongoing deterioration in immune function which directly correlates with disease, in particular acquired immunodefciency syndrome (AIDS). However, it is not known whether FIV-induced immunosuppression is progressive or related to the clinical condition. This study examined changes in lymphocyte subset numbers of serial samples, taken from cohorts of FIV-positive and FIV-negative cats over an 18-month period. FIV-positive cats were clinically staged as asymptomatic carriers (AC) or cats with AIDS-related complex (ARC), and FIV-negative cats matched and staged on the basis of similar diseases. During the course of the study, 4 FIV-positive cats developed AIDS, classed as the terminal stage of infection. There were no significant differences in the mean absolute numbers of any lymphocyte subset between the onset (to) and the completion (t18) of the study. Similarly there were no significant changes in subset numbers during the 18 months preceding the development of AIDS. While the study period was brief and the sample sizes small, it is postulated that FIV infection in Australia may not necessarily cause progressive immunodeficiency and that FIV-induced immunosuppression (as measured by subset analysis) may not be well correlated with the clinical status of the infected cat.  相似文献   

International conference on FMD     

Dr Gardner Murray 《Australian veterinary journal》2002,80(1):21-21

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Suspected Cryptostegia grandiflora (rubber vine) poisoning in horses     

DR COOK  GW CAMPBELL  AR MELDRUM 《Australian veterinary journal》1990,67(9):344-344

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Determination of Safe Depth of Pin Penetration for Repair of Distal Femoral Physeal Fractures in Immature Dogs: A Comparison of Normograde and Retrograde Pin Placement     

DRAGAN LORINSON DR MED VET    DARRYL L. MILLIS MS  DVM  DIPLOMATE ACVS  RONALD M. BRIGHT DVM  MS  DIPLOMATE ACVS 《Veterinary surgery : VS》1997,26(6):467-471

Objective —The purpose of this study was to determine the depth that implants may be safely placed into the distal femoral epiphysis (DFE) for the repair of distal femoral physeal fractures.
Study Design —The depth of the DFE was related to the radiographic thickness of the patella in this experimental study.
Animals or Sample Population —Twenty immature canine cadavers.
Methods —Patella thicknesses were measured from lateral radiographs. Actual DFE depths were determined for pins driven in normograde fashion and for pins driven retrograde from the central depression between the metaphyseal pegs and from the cranial pegs. The association of DFE depth and patella thickness was evaluated using linear regression analysis. Using 95% confidence intervals, rules for estimating the safe depth of implant placement into the DFE were determined.
Results —DFE depth had significant correlation with patella thickness for pins placed in retrograde fashion from the central depression between the metaphyseal pegs (r²= .83) and from the cranial pegs (r²= .82) and for pins placed in normograde fashion (r²= .65).
Conclusions —Based on 95% confidence intervals, pins placed in retrograde fashion from the central depression between the metaphyseal pegs may be safely driven into the DFE a distance equal to 140% of patella thickness. Pins placed from the cranial metaphyseal pegs may be driven to a depth equal to 80% of patella thickness, and pins placed in normograde fashion may be driven to a depth equal to 30% of patella thickness.
Clinical Relevance —Measurement of patella thickness assists the surgeon in determining the approximate depth that pins may be driven into the DFE without penetrating the articular surface of the stifle joint.  相似文献   

Conservative management of minimally displaced radial fractures in three horses     

S. MATTHEWS  AJ DART  BA DOWLING  DR HODGSON 《Australian veterinary journal》2002,80(1):44-47

Minimally displaced, spiral, radial fractures were diagnosed in three adult horses. Two horses had open fractures and in one horse the fracture was closed. A diagnosis was made on radiographs taken 24 h, 5, and 9 days after the fracture. There was minimal displacement of the fracture fragments despite the considerable time which had elapsed between fracture and diagnosis and an unfavourable prognosis with internal fixation, so conservative therapy was the preferred method of treatment. One horse developed a sequestrum and draining sinus, which was treated surgically under general anaesthesia 3 months after diagnosis of the fracture. Other complications were minimal and transient. Two horses were being used for pleasure riding 12 months after fracture and one horse was pasture sound at 8 months.  相似文献   

Surgical correction of anorectal atresia and rectovaginal fistula in an alpaca cria     

DB CARRARO  AJ DART  NPH HUDSON  CM DART  DR HODGSON 《Australian veterinary journal》1996,74(5):352-354

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Epidemiology theory and disturbance spread on landscapes     

R. V. O’Neill  R. H. Gardner  M. G. Turner  W. H. Romme 《Landscape Ecology》1992,7(1):19-26

Abtract Epidemiology models, modified to include landscape pattern, are used to examine the relative importance of landscape geometry and disturbance dynamics in determining the spatial extent of a disturbance, such as a fire. The models indicate that, except for very small values for the probability of spread, a disturbance tends to propagate to all susceptible sites that can be reached. Therefore, spatial pattern, rather than disturbance dynamic, will ordinarily determine the total extent of a single disturbance event. The models also indicate that a single disturbance will seldom become endemic,i.e., always present on the landscape. However, increasing disturbance frequency can lead to a landscape in which the proportion of susceptible, disturbed, and recovering sites are relatively constant. Research supported by Ecological Research Division, Office of Health and Environmental Research, U.S. Department of Energy under contract No. DE-AC05-840R21400 with Martin Marietta Energy Systems, Inc. Contribution No. 10 to the Sevilleta LTER program. Environmental Sciences Division Publication No. 3812, ORNL.  相似文献   

DOPPLER MEASUREMENT OF SPLANCHNIC BLOOD FLOW DURING DIGESTION IN UNSEDATED NORMAL DOGS     

Sabine  Riesen  DR MED VET  Valerie  Schmid  DR MED VET  Lorrie  Gaschen  DVM  DR MED VET  Andre  Busato  DR MED VET MSC  Johann  Lang PD  DR MED VET 《Veterinary radiology & ultrasound》2002,43(6):554-560

The purpose of this study was to measure splanchnic blood flow during digestion in unsedated dogs by using duplex Doppler sonography. The study population consisted of 12 healthy dogs. Blood flow in the cranial mesenteric artery, the celiac artery, and the aorta was measured before a test meal and at 20, 60, and 90 minutes after eating. The following measurements were made or calculated: vessel diameter, peak systolic velocity, end diastolic velocity, mean velocity, resistive index, pulsatility index, and flow volume. There was a significant postprandial decrease in the resistive and pulsatility indices in both the cranial mesenteric (preprandial RI = 0.867, postprandial RI = 0.796, preprandial PI = 3.033, postprandial PI = 2.173) and the celiac (preprandial RI = 0.854, postprandial RI = 0.769, preprandial PI = 2.639, postprandial PI = 1.930) arteries. In both vessels the end diastolic velocity, the mean velocity, and the flow volume increased significantly postprandially. These changes occurred significantly earlier in the celiac artery than in the cranial mesenteric artery. The findings most likely correspond to postprandial splanchnic vasodilation. Doppler ultrasound provide a good methode of detecting changes in postprandial splanchnic blood flow in the dog.  相似文献