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Rupture of the suspensory ligament at the insertions on the proximal sesamoid bones, and of the superficial flexor tendon of the left fore limb, occurred in an adult Angus bull as a result of fighting. There was severe hyperextension of the metacarpophalangeal (MCP) joint with the dewclaws almost touching the ground. Radiographs revealed severe hyper-extension of the MCP joint with the sesamoid bones aligned directly distal to the metacarpus. Initially, a full length fiberglass cast was applied with the limb partially flexed within the cast and the heels elevated. The cast was replaced twice. The cast was removed after 136 days and the bull was bearing full weight on the limb. Prolonged immobilisation of the limb produced new bone in the area (a normal response in cattle) to cause ankylosis of the traumatized MCP joint and partial ankylosis of the carpus. The bull was being used for pasture breeding one year after the injury.  相似文献   
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Objective The mechanical properties of three materials (No. 2 polypropylene, No. 5 polybutilate-coated multifilament polyester and 18, 27 and 36 kg test monofilament nylon leader material) commonly used for extra-capsular stabilisation of the stifle in dogs with cranial cruciate ligament insufficiency were determined. The ability of No. 5 polybutilate-coated multifilament polyester and 36 kg test monofilament nylon leader material, when placed as extra-capsular sutures, to mitigate cranial drawer was evaluated in hindlimbs of cadavers. Design An in vitro mechanical study. Animals Seven pairs of hindlimbs harvested from adult greyhound dogs recently euthanased for other reasons. Procedure Samples of each material, including samples of 27 kg test leader material that had been sterilised by one of three methods (ethylene oxide, one or five cycles in an autoclave), were loaded to determine tensile and stress relaxation properties. The effect of cyclic loading on a No. 5 polybutilate-coated multifilament polyester and 36 kg test leader material was also determined. Using the harvested hindlimbs, cranial drawer was measured before and after transection of the cranial cruciate ligament and on the first and twelfth cycle following extra-capsular stabilisation with either No. 5 polybu-tilate-coated multifilament suture or 36 kg test leader material. Results Leader material was found to have the most suitable mechanical characteristics for use as extracapsular stabilisation of the cranial cruciate ligament deficient stifle. Of the sterilisation methods, ethylene oxide was found to have the least detrimental effects on the handling and material characteristics of the leader material. Stifles stabilised with 36 kg test leader material had significantly less drawer than those stabilised with No. 5 polybutilate-coated multifilament polyester suture. Clinical implications Monofilament nylon leader material would appear to have suitable mechanical properties for extra-capsular stabilisation of the cranial cruciate ligament deficient stifle. If possible the material should be sterilised using ethylene oxide.  相似文献   
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Concentrations of benomyl greater than 10 ng ml?1 inhibited germination and hyphal growth of the vesicular-arbuscular mycorrhizal fungus Glomus caledonicum on water agar. This effect was attributable to only the activity of methyl-2-benzimidazole carbamate, one of the two hydrolysis products of benomyl. Hyphal growth but not germination was affected by the pH of water agar buffered with 10 mm 2-(N-morpholino)ethane sulphonic acid.  相似文献   
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The mechanisms controlling axon guidance are of fundamental importance in understanding brain development. Growing corticospinal and somatosensory axons cross the midline in the medulla to reach their targets and thus form the basis of contralateral motor control and sensory input. The motor and sensory projections appeared uncrossed in patients with horizontal gaze palsy with progressive scoliosis (HGPPS). In patients affected with HGPPS, we identified mutations in the ROBO3 gene, which shares homology with roundabout genes important in axon guidance in developing Drosophila, zebrafish, and mouse. Like its murine homolog Rig1/Robo3, but unlike other Robo proteins, ROBO3 is required for hindbrain axon midline crossing.  相似文献   
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Compounds with strong thermodynamic affinity for carbon dioxide (CO(2)) have been designed and synthesized that dissolve in CO(2), then associate to form gels. Upon removal of the CO(2), these gels produced free-standing foams with cells with an average diameter smaller than 1 micrometer and a bulk density reduction of 97 percent relative to the parent material.  相似文献   
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Norepinephrine: release from brain by d-amphetamine in vivo   总被引:1,自引:0,他引:1  
After injection of H(3)-norepinephrine into the left lateral cerebral ventricle of cats, the lateral and third cerebral ventricles were perfused with an artificial cerebrospinal fluid. Addition of d-amphetamine to the perfusion fluid caused a significant increase in the concentration of H(3)-norepinephrine in the effluent.  相似文献   
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Small doses of endotoxin evoked a dramatic biphasic response of opioid peptide secretion into blood in sheep. The first phase began within minutes and coincided with a brief hypertensive response to endotoxin well before the appearance of fever or hypotension. The ratio of beta-endorphin to beta-lipotropin fell abruptly at the onset of the second phase of release, suggesting early depletion of a pool rich in beta-endorphin and subsequent emergence of a pool rich in unprocessed precursor. The concentration of cerebrospinal fluid opioids increased tenfold during the second phase. Naloxone administration augmented endotoxin-induced opioid secretion in both early and late phases, suggesting a short-loop feedback regulation of stress-induced endorphin secretion.  相似文献   
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