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11.
CASE DESCRIPTION: A 9-year-old dog was evaluated for traumatic cervical myelopathy after a surgical attempt to realign and stabilize the C2 and C3 vertebrae. CLINICAL FINDINGS: The dog could not ventilate spontaneously and was tetraplegic; positive-pressure ventilation (PPV) was maintained. Myelography and computed tomography revealed spinal cord compression with subluxation of the C2 and C3 vertebrae and extrusion of the C2-3 intervertebral disk. TREATMENT AND OUTCOME: Surgically, the protruding disk material was removed and the vertebrae were realigned with screws and wire. For PPV, assist control ventilation in volume control mode and then in pressure control mode was used in the first 6 days; this was followed by synchronized intermittent mandatory ventilation until 33 days after the injury; then only continuous positive airway pressure was provided until the dog could breathe unassisted, 37 days after the injury. Physical therapy that included passive range of motion exercises, neuromuscular electrical stimulation, and functional weight-bearing positions was administered until the dog was discharged 46 days after injury; the dog was severely ataxic and tetraparetic but could walk. Therapy was continued at home, and 1 year later, the dog could run and had moderate ataxia and tetraparesis. CLINICAL RELEVANCE: Hypoventilation with tetraparesis in traumatic spinal cord injury can be successfully treated with PPV exceeding 30 days, surgery, and physical therapy.  相似文献   
12.

Objective

To compare the effects of MK-467 during isoflurane anaesthesia combined with xylazine or dexmedetomidine on global and gastrointestinal perfusion parameters.

Study design

Prospective, randomized experimental trial.

Animals

A total of 15 warmblood horses.

Methods

Horses were divided into two groups for administration of either dexmedetomidine (D) or xylazine (X) for premedication (D: 3.5 μg kg?1; X: 0.5 mg kg?1) and as constant rate infusion during isoflurane anaesthesia (D: 7 μg kg?1 hour?1; X: 1 mg kg?1 hour?1). During anaesthesia, heart rate, mean arterial blood pressure (MAP), systemic vascular resistance index (SVRI) and cardiac index (CI) were measured. Microperfusion of the colon, jejunum and stomach was measured using laser Doppler flowmetry. After 2 hours of stabilization, MK-467 (250 μg kg?1) was administered, and measurements were continued for another 90 minutes. For statistical analysis, the permutation test and Wilcoxon rank-sum test were used (p < 0.05).

Results

There were no differences in baseline measurements between groups. The MK-467 bolus resulted in a significant decrease in MAP (D: –58%; X: –48%) and SVRI (D: –68%; X: –65%) lasting longer in group D (90 minutes) compared to group X (60 minutes). While CI increased (D: +31%; X: +35%), microperfusion was reduced in the colon (D: –44%; X: –34%), jejunum (D: –26%; X: –33%) and stomach (D: –37%; X: –35%).

Conclusions and clinical relevance

Alpha-2-agonist induced vasoconstriction was reversed by the MK-467 dose used, resulting in hypotension and rise in CI. Gastrointestinal microperfusion decreased, probably as a result of insufficient perfusion pressure. An infusion rate for MK-467 as well as an ideal agonist/antagonist ratio should be determined.  相似文献   
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Since recent studies reveal citric acid to be favorable for estimating plant‐available P in soils, we investigated if it can also be used for assessing other nutrients. According to our results, it provides stronger correlations with the tree nutrition for Mg (beech, spruce), Ca+K (beech) and Fe (spruce) than the standard methods for determining exchangeable cations. Thus, when estimating plant‐available P by citric acid‐extraction, these cations should be additionally measured in ICP analysis.  相似文献   
15.
Use of bone morphogenetic proteins for augmentation of bone regeneration   总被引:1,自引:0,他引:1  
A large body of preclinical and clinical data now documents that recombinant BMPs can be used for skeletal regeneration in humans and animals. Recombinant human BMP-2 and BMP-7 have been approved for use in human patients with long-bone fractures and nonunions and in patients undergoing lumbar fusion or various maxillofacial and dental regenerative procedures. These products have also been made available for veterinary use.  相似文献   
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OBJECTIVE: To evaluate the effect of 2 hydroxyethyl starch (HES) preparations (ie, HES solution with a molecular weight of 600 kd and a degree of substitution of 0.7 [HES 600/0.7] and a calcium-containing polyionic HES solution with a molecular weight of 670 kd and a degree of substitution of 0.75 [HES 670/0.75]) on canine platelet function. SAMPLE POPULATION: Blood samples from 10 healthy adult dogs. PROCEDURES: Dilution of citrated whole blood was performed with saline (0.9% NaCl) solution, HES 600/0.7, and HES 670/0.75 at ratios of 1:9 (ie, 1 part saline solution or colloid to 9 parts whole blood) and 1:3. Measurements of time to platelet plug formation in a capillary tube (ie, closure time) were made by use of a bench-top platelet function analyzer with collagen and ADP platelet agonists. RESULTS: Mean baseline closure time was 68.0 +/- 15.3 seconds. A 1:3 dilution of whole blood with saline solution, HES 600/0.7, and HES 670/0.75 resulted in mean closure times of 85.8 +/- 15.7 seconds, 100.6 +/- 18.6 seconds, and 101.6 +/- 16.2 seconds, respectively. Closure time following 1:3 dilution of whole blood with saline solution was significantly different from baseline and from 1:9 dilution with saline solution. Closure time following 1:3 dilution of whole blood with HES 670/0.75 was significantly different from baseline, 1:3 and 1:9 dilutions with saline solution, and 1:9 dilutions with HES 600/0.7 or HES 670/0.75. CONCLUSIONS AND CLINICAL RELEVANCE: Saline solution, HES 600/0.7, and HES 670/0.75 affect canine platelet function by prolonging closure times; HES solutions prolonged closure time to a greater extent than saline solution.  相似文献   
20.
The objective of this study was to establish a technique for radiographic examination of the coxofemoral joint and adjacent bony structures in standing cattle. Left (or right) 30° dorsal-right (or left) ventral radiographic views of the coxofemoral joint region of standing cattle (n = 10) with hind limb lameness were evaluated retrospectively. In addition, an experimental study of oblique laterolateral views of the coxofemoral joint region of a bovine skeleton at angles of 15-45° was carried out to determine the optimal position for visualization of the hip region. In the 10 clinical patients, the bodies of the ilium and ischium, the acetabulum and proximal third of the femur could be assessed. Six of these cattle had fractures of the body of the ilium and body of the ischium, five with and one without involvement of the acetabulum, two had craniodorsal and one caudoventral luxation of the femur and one had a femoral neck fracture. The described laterodorsal-lateroventral radiographs of the hip region in standing cattle were suitable for assessing the coxofemoral joint, the proximal aspect of the femur and parts of the ischium, ilium and pubis. After testing the optimal angle on the skeleton, it was seen that distortion and superimposition were minimized by positioning the X-ray beam at an angle of 25° to the horizontal plane. It can be concluded that the described technique improves the evaluation of injuries of the coxofemoral region in cattle. With the appropriate angle, the technique can also be applied in recumbent cattle.  相似文献   
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