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191.
Reasons for study: Detailed anatomy of the equine cervical articular process joints (APJs) has received little attention in the literature and yet disorders of this joint have been linked to spinal cord compression resulting in severe clinical signs such as ataxia and weakness. This study aimed to describe the 3D anatomy of the APJ in relation to the spinal cord in the horse. Hypothesis: Artificial distension of the APJ causes the joint pouches to extend into the vertebral canal, with the potential for APJ effusion to cause spinal cord compressive disease. Methods: Six cadaveric necks (C1–C7) of clinically normal horses were used in this study. Computed tomography scans of the cervical APJ were acquired after injection of a negative contrast agent to maximal distension. The resulting images were semi‐automatically segmented using greyscale thresholding and reconstructed in 3D by polygonal surface meshing. The 3D reconstructions were used to assess the topographic anatomy of the APJ in relation to the spinal cord and to measure joint volume at each cervical vertebra in relation to vertebrae size. Results: Joint volume varied significantly between joint location (P<0.0001) and was positively correlated to the vertebral site (from cranial to caudal) (r = 0.781, P<0.0001). After distension, the medial outpouch of the APJ extended towards the vertebral canal from a dorsolateral location but in none of the 6 horses was there apparent compression of the dura mater surrounding the spinal cord. There was no significant difference in the extent of medial outpouch at any vertebral level (P = 0.104). Flexion of the neck resulted in minor changes to the shape of the APJ but did not result in the medial outpouch encroaching any closer to the spinal cord. Conclusions: From this study, it appears that in the absence of any other soft tissue or bony changes an effusion of the APJ is unlikely to cause spinal cord compression. However, given that the APJ and spinal cord are in close approximation, in the presence of other anatomical changes, an effusion may have the potential to cause compression. Potential relevance: This study confirms that the APJ extend into the dorsolateral aspect of the vertebral canal in a ventromedial direction, suggesting that oblique myelographic views are recommended for the diagnosis of spinal cord compression when pathology of the APJ is suspected. 相似文献
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194.
Influence of orchard soil management on lumbricids, especially Lumbricus terrestris L. In a long-term soil management experiment (apple orchard treated with cultivation methods such as grass mulch, grass harvest, straw mulch, clean cultivation) 6 plots were selected in order to study the abundance and biomass of earthworm populations. The following results were obtained: In all treatments with the exception of straw mulch L. terrestris represented the majority (60.5% on average) of the lumbricid population. Their share in the biomass amounted to 93.3%. The earthworm biomass was the highest in grass mulch; a close correlation was observed between the litter production (grass and leaves) and the biomass of L. terrestris. Added farm yard-manure on plots with grass mulch had no additional positive effect on earthworms. Although a higher earthworm biomass was found under grass mulch in comparison with straw mulch, the species diversity was higher in the latter. Clean cultivation had a highly detrimental effect on all earthworms, especially on the horizontally burrowing species. The annual nitrogen turnover by L. terrestris in mulched orchards was estimated to approx. 50 kg N/ha. 相似文献
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Multi-drug-resistant Enterococcus spp. as a cause of non-responsive septic synovitis in three horses
CL Herdan E Acke M Dicken RM Archer SF Forsyth EK Gee 《New Zealand veterinary journal》2013,61(5):297-304
Abstract CASE HISTORY: Three Thoroughbred horses, a 6-week-old filly (Case 1), a 15-year-old broodmare (Case 2) and a yearling filly (Case 3), sustained synovial sepsis secondary to trauma. CLINICAL FINDINGS: Case 1 presented with a heel bulb laceration communicating with the distal interphalangeal joint. Arthroscopic lavage was performed and treatment commenced using systemic and local broad spectrum antimicrobial drugs. A pure growth of multi-drug-resistant (MDR) Enterococcus gallinarum was cultured from samples of synovium and joint fluid. Antimicrobial treatment was changed according to the susceptibility results. Response to treatment was poor and despite repeat arthroscopic lavage and intra-osseous regional perfusion of antimicrobials the filly was subject to euthanasia 24 days after the initial injury. Post-mortem examination confirmed septic synovitis, cartilage degeneration and osteomyelitis. Case 2 sustained a full thickness wound to the carpus which was sharply debrided and closed. The wound dehisced with effusion within the tendon sheath. Drainage was established and treatment included systemic broad spectrum antimicrobials, topical lavage with povodine-iodine and manuka honey infusion. A mixed infection including MDR Enterococcus faecalis was cultured from the synovial fluid. Antebrachiocarpal joint effusion developed 21 days after initial injury and joint sepsis was confirmed. Arthroscopic lavage and tendon sheath debridement were performed, followed by treatment with systemic and local antimicrobials. The mare improved and was discharged. Three months later lameness recurred and corticosteroids were administered intra-articularly. The mare became non-weight bearing lame and was subject to euthanasia. Post-mortem examination confirmed joint sepsis of the antebrachiocarpal and intercarpal joint. Case 3 presented with a complete articular open fracture of the tibial crest. Under general anaesthesia the fracture was stabilised and the wounds debrided and closed. Systemic broad-spectrum antimicrobials were administered. Six days later the wound dehisced and a bone fragment was removed. Three weeks post-surgery the wound deteriorated with a purulent discharge. Culture of the discharge revealed a mixed bacterial infection, including a MDR Enterococcus faecalis. Femoropatellar joint involvement was confirmed, and treatment included joint lavage, local and systemic antibiosis, and manuka honey instilled into the wound. The filly initially improved, and then deteriorated such that euthanasia was performed. DIAGNOSIS: All three cases had synovial sepsis with MDR Enterococcus spp. CLINICAL RELEVANCE: Increased awareness of MDR pathogens in equine wound infections is essential. Prompt diagnostic testing, appropriate therapy, infection control strategies and on-going monitoring and management are vital to limit the clinical impact of these organisms. 相似文献
197.
Keum T. Hwang Curtis L. Weller Susan L. Cuppett Milford A. Hanna 《Cereal Chemistry》2004,81(3):345-349
Grain sorghum can be a major source of policosanols, long‐chained alcohols, that have beneficial physiological activities. Sorghum dried distillers grains (DDG), a by‐product of ethanol production from grain sorghum, contain a large amount of policosanols. Content and composition of policosanols in long‐chained lipids extracted from grain sorghum kernels and DDG were determined. Long‐chained lipids were extracted using hot hexane or hot ethanol. The major components of the long‐chained lipids extracted from grain sorghum kernels, as determined using HPLC, were policosanols (37–44%), aldehydes (44–55%), and acids (4–5%). Long‐chained lipids from DDG contained 52% policosanols, 23% aldehydes, 6.4% acids, and 17% wax esters/steryl esters. Composition of policosanols in DDG matched the composition in grain sorghum kernels, as determined by gas chromatography, even though the content of policosanols in DDG was greater than the content in grain sorghum kernels. Policosonal composition ranges were 0–1% C22:0, 0–3% C24:0, 6–8% C26:0, 1% C27:0, 43–47% C28:0, 1–2% C29:0, 40–43% C30:0, and 1–4% C32:0. 相似文献
198.
Rheology of zein solutions in aqueous ethanol. 总被引:3,自引:0,他引:3
Aqueous ethanol solutions prepared with commercial zein exhibited Newtonian behavior. Temperature, zein concentration, and ratio of water to ethanol affected viscosity of the zein solutions. The influence of temperature on zein solution viscosity was expressed by an Arrhenius-type equation. As zein concentration increased, solution viscosity exponentially increased. Generally speaking, viscosity decreased when the ethanol concentration increased. Parameters were estimated for an Arrhenius-type equation to describe the viscosity as a function of temperature, zein concentration, and ethanol concentration. 相似文献
199.
Soil Chemical and Physical Properties Associated with Suppression of Take-all of Wheat by Trichoderma koningii 总被引:1,自引:0,他引:1
ABSTRACT Trichoderma koningii, originally isolated from a take-all-suppressive soil in Western Australia, has been shown to protect wheat against take-all disease and increase grain yield in field trials in Australia, China, and the United States. However, within a region, the level of protection provided by T. koningii can dramatically vary between field sites. We evaluated suppression of take-all by this fungus in eight silt loams from the Pacific Northwest of the United States and the influence of 21 abiotic soil parameters on biocontrol activity. While T. koningii significantly increased plant growth and reduced disease severity in all eight silt loams, the level of protection varied significantly among the soils. Disease suppression was not associated with the conduciveness of a soil to take-all, but rather to the supportiveness of a soil to biocontrol activity. Biocontrol activity was positively correlated with iron, nitrate-nitrogen, boron, copper, soluble magnesium, and percent clay, and negatively correlated with soil pH and available phosphorus. Principal component factor analysis using these eight variables resulted in a three-component solution that accounted for 95% of the variation in disease rating. Least squares regression analysis (R(2) = 0.992) identified a model that included nitrate-nitrogen, soil pH, copper, and soluble magnesium, and described the variance in take-all suppression by T. koningii. Potential applications of these results include amending soil or inoculants with beneficial factors that may be lacking in the target soil and customizing biocontrol treatments for sites that have parameters predictive of a favorable environment for disease suppression. 相似文献
200.
R E Weller R R Pool W J Hornof 《Journal of the American Veterinary Medical Association》1979,175(1):56-60
A 9-year-old male German Shepherd Dog with osteogenic sarcoma involving the right humerus was treated by scapulohumeral disarticulation and adjuvant chemotherapy. Doxorubicin was used, at a dosage of 30 mg/m2 of body surface. Chemotherapy was unsuccessful, and 4 months after surgery, the dog developed multiple metastases of osteogenic sarcoma in the appendicular skeleton, a metastatic pattern rarely observed with primary bone tumors. 相似文献