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91.
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Objective —To describe the tenoscopic anatomy of the carpal sheath of the flexor tendons (carpal sheath) viewed from a lateral approach.
Study Design —Tenoscopic observation of structures within the carpal sheath subsequently confirmed by dissection.
Animals or Sample Population—12 equine cadaveric forelimbs.
Methods —The limbs were positioned lateral side up with the carpus slightly flexed. After distention of the carpal sheath, a portal for the arthroscope was made approximately 3 cm proximal to the distal radial physis and 2.5 cm caudal to the radius between the tendons of the ulnaris lateralis and lateral digital extensor muscles.
Results —A lateral tenoscopic approach was adequate to identify all structures within the carpal sheath. From proximal to distal, structures identified using this approach were the radial head of the deep digital flexor muscle, accessory ligament of the tendon of the superficial digital flexor muscle, distal radial physis, tendons of the superficial and deep digital flexor muscles, accessory carpal bone, antebrachiocarpal and middle carpal joints, and vincula of the tendon of the deep digital flexor muscle.
Conclusions —A lateral tenoscopic approach offered an easy, repeatable entry into the carpal sheath and allowed good observation of all structures within the sheath except for the medial borders of the tendons of the deep and superficial digital flexor muscles.
Clinical Relevance —Applications of a lateral tenoscopic approach to the carpal sheath include diagnostic procedures, lavage and synovial resection for septic tenosynovitis, desmotomy of the accessory ligament of the tendon of the superficial digital flexor muscle for flexural deformity or tendinitis, and removal of osteochondromas from the distal radial metaphysis.  相似文献   
94.
FLUORIDE ADSORPTION BY ILLINOIS SOILS   总被引:8,自引:0,他引:8  
Fourteen surface and 6 subsurface horizons of Illinois soils adsorbed significant amounts of F? with release of OH?. At low concentrations, adsorption was described by both Langmuir and Freundlich isotherms. The calculated Langmuir adsorption capacities were related to pH, clay, organic carbon, and amorphous aluminum contents. Two soils with different gross chemical properties behaved in essentially the same manner, with adsorption maxima occuring between pH 5.5 and 6.5. The similarity between adsorption at different pH values for the soils and those for bauxite, allophane and synthesized ‘soil chlorite’, and the lack of adsorption maxima between pH 5.5 and 6.5 for pure kaolinite and montmorillonite, suggest that F? adsorption in the soils is due primarily to the presence of amorphous aluminum oxyhydroxides which are common weathering products in these soils.  相似文献   
95.
Reduced herbicide doses in field crops: A review   总被引:2,自引:1,他引:2  
Farmers are becoming increasingly interested in more comprehensive weed management programs that reduce weed populations over time and in the use of reduced herbicide doses that lower their production costs. Research indicates that there is good potential to reduce the number of herbicide applications and utilize lower herbicide doses within competitive cropping systems. Diverse crop rotations, competitive cultivars, higher crop seed rates, reduced row spacing, specific fertilizer placement, and cover crops have been identified as integral components of competitive cropping systems. This review paper explores the potential for successful use of reduced herbicide doses within competitive cropping systems that have a multiyear approach to weed management. The utilization of decision support systems or new methods of assessing active weed growth are discussed in light of further enhancing the successful use of reduced herbicide doses and advising farmers on when (and when not) they might be a viable option.  相似文献   
96.
Gene expression was compared under favorable germination conditions between dormant and non-dormant seeds of rice paddy Echinochloa weeds and a domesticated Echinochloa species lacking dormancy. Two dormancy-specific cDNAs, Ecd1 and Ecd2 , were identified by differential display. Northern blot analysis revealed that these genes were more strongly expressed in dormant seeds than in non-dormant seeds. A database search for the Ecd1 sequence revealed no significant homology with any known proteins, but the Ecd2 sequence was highly homologous with the α-chain of mitochondrial H+-transporting adenosine triphosphate (ATP) synthase in rice ( Oryza sativa L.). These findings indicate that the gene encoding the enzyme associated with conventional aerobic respiration is more abundantly transcribed in dormant seeds. The results reported in the present study suggest that dormant seeds of paddy Echinochloa weeds, which appear during the period when paddy soil becomes aerobic by drainage, may maintain viability primarily by efficient conventional aerobic respiration, including ATP synthesis catalyzed by the mitochondrial H+-transporting ATP synthase.  相似文献   
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Abstract— Culture supernatants from six Staphylococcus hyicus isolates were concentrated by ultrafiltration and were injected intradermally into the abdominal skin of 2-week-old piglets. Two distinct types of reaction were observed; (1) a focal erythema and (2) an exfoliative reaction with crusting. The severity of these reactions and the number of animals affected differed between isolates. The exfoliative reaction observed in these skin tests may be a good indicator of virulence. Résumé— Les surnageants de six souches de Staphylococcus hyicus ont été concentrés par ultrafiltration et furent injectés par voie intradermique dans la peau de l'abdomen de porcelets ägés de deux semaines. Deux types distincts de réactions furent observés: (1) un éryhème focal et (2) une réaction d'exfoliation avec apparition de croûtes. L'intensité de ces réactions et le nombre d'animaux atteints différaient selon les souches. La réaction d'exfoliation observée lors de ces tests pourrait être un bon indicateur de virulence. Zusammenfassung— Überstände der Kultur von sechs Staphylococcus hyicus-Isolaten wurden durch Ultra-zentrifugieren konzentriert und bei 2 Wochen alten Ferkeln intradermal in die Abdominalhaut injiziert. Es konnten zwei deutlich unterscheidbare Reaktionen beobachtet werden: (1) ein fokales Erythem und (2) eine exfoliative Reaktion mit Krustenbildung. Die Schwere dieser Reaktionen und die Zahl der betroffenen Tiere war je nach Isolat unterscheidlich. Die exfoliative Reaktion bei diesen Hauttests könnte ein guter Indikator für die Virulenz sein. Resumen Los sobrenadantes de 6 cultivos diferentes de Staphylococcus hyicus se concentraron mediante ultrafiltración y se inyectaron via intradérmica en la piel abdominal de lechones de dos semanas de edad. Se observaron dos tipos de reacción: (1) un eritem focal y (2) una reacción exfoliativa y costrosa. La gravedad de las reacciones y el nümero de animales afectados variaba en functión del cultivo utilizado. La reacción exfoliativa que se observó en estos tests intradérmicos puede ser un buen indicador de virulencia.  相似文献   
99.
Résumé— Une dermite s'est développé subitement dans un chenil de 30 chiens courants chez 12 d'entre eux. A la fois des males et des femelles étaient atteints et les lésions étaient limitées aux régions non pigmentées, principalement la face, les membres et la région inguinale. Initiallement les lésions étaient un érythème, un ?déme et une exsudation. Des croutes brunes se sont ensuite formées, et chez la plupart des animaux trés atteints, la peau a laissé la place à un escarre brun agglutiné dans les poils. Un pus malodorant était accumulé sous l'escarre. Les chiens moyennement atteints ont guerie sans traitement et les plus atteints ont guerie après exérèse des escarres et antibiothérapie. Aucun des chiens n'est mort et la plupart ont retrouvé une peau normale au bout de 3 mois. Cliniquement et histologiquement, ces lésions étaient compatibles avec une photosensibilisation, mais il a été impossible de retrouver l'agent causal. [Fairley, R. A., MacKenzie, I. S. Photosensitivity in a kennel of harrier hounds (Photosensibilisation dans un chenil de chiens courants). Resumen— Una condición de la piel se desarrolló de repente en 12 de 30 perros harrier. Afectó a machos y hembras y las lesiones se limitaban a areas de piel sin pigmento, principalmente la cara, patas e ingle. Inicialmente, la piel afectada estaba eritematosa, edematosa y húmeda. Entonces se formaban costras marrones y, en los perros más gravemente afectados, la piel se desprendia dejando una costra marrón seca enredada en el pelo. Debajo de la costra se acumulaba un exudado purulento maloliente. Los perros levemente afectados mejoraron sin tratamiento y los más gravemente afectados lo hicieron despues de tratamiento antibiotico y extirpación de la costra y el pus acumulado. Ninguno de los perros murió y la piel de la mayoria de ellos era normal en 3 meses. Clinica e histologicamente, las lesiones eran compatibles con una condición de fotosensibilidad de la piel, pero las investigaciones no lograron encontrar ningún agenté fotodinámico responsable. [Fairley, R. A., Mackenzie, I. S. Photosensitivity in a kennel of harrier hounds (Fotosensibilidad en una perrera de perros harrier). Abstract— A skin condition developed suddenly in 12 out of 30 harrier hounds. Both males and females were affected and lesions were confined to areas of unpigmented skin, mainly on the face, legs and groin. Initially the affected skin was erythematous, edematous and moist. Brown crusts then formed, and in the most severely affected dogs the skin sloughed leaving a dry brown eschar matted in the hair. A foul-smelling purulent exudate accumulated under the eschar. The mildly affected dogs improved without treatment and the most severely affected dogs improved following antibiotic treatment and the removal of the eschar and the accumulated pus. None of the dogs died and the skin of most dogs was normal within 3 months. Clinically and histologically, the lesions were compatible with a photosensitive skin condition, but investigations failed to find any responsible photodynamic agent.  相似文献   
100.
Abstract— The effects of an inhibitor-producing strain of Staphylococcus chromogenes on the colonisation and disease produced by virulent and avirulent strains of Staphylococcus hyicus were examined. In the presence of S. chromogenes the colonisation of the virulent strain was reduced one thousand fold and the onset of lesions was delayed by 7 days. The ability of the avirulent strain of S. hyicus to colonise skin was greatly reduced and populations became almost undetectable within 6 days of inoculation. Résumeé— Les effets d'une souche de Staphylococcus chromogenes, productrice d'un facteur d'inhibition, ont été examinés sur la colonisation et la maladie produites par des souches non virulentes et virulentes de Staphylococcus hyicus. En présence de S. chromogenes, la colonisation de la souche virulente a été réduite de 1000 fois, et l'apparition des lésions a été retardée de 7 jours. La faculté pour la souche non virulente de S. hyicus de coloniser la peau a été considérablement réduite et les populations sont devenues à peu près introuvables 6 jours après l'inoculation. Zusammenfassung— Die Wirkungen Inhibitor-produzierenden Art von Staphylococcus chromogenes auf die Kolonisierung und Erkrankung der Haut durch virulente und avirulente Arten von Staphylococcus hyicus wurden untersucht. In Gegenwart von S. chromogenes wurde die Kolonisierung der virulenten Art um den Faktor 1000 verringert und des Auftreten der Hautveränderungen um 7 Tage verzögert. Die Fähigkeit zur Kolonisierung der Haut durch die avirulente 5. hyicus-Art wurde sehr stark verringert, ihre Population konnte innerhalb von 6 Tagen nach Inokulation nicht mehr nachgewiesen werden. Resumen Se estudian los efectos de una cepa de Staphylococcus chromogenes productora de un inhibidor sobre la colonización y la enfermedad producida por cepas virulentas y avirulentas de Staphylococcus hyicus. En presencia de S. chromogenes la colonización de cepas virulentas se redujo a una milésima parte y la aparición de lesiones se retrasó 7 días. La capacidad de cepas avirulentas de S. hyicus para colonizar la piel se vió fuertemente reducida y las poblaciones bacterianas eran prácticamente no detectables a los 6 días de la inoculación.  相似文献   
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