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41.
Abstract— Following dermal infection of previously sensitized sheep with orf virus, differences in cell phenotype and kinetics are observed in afferent lymph flowing into the local lymph node compared to efferent lymph exiting the node. Afferent lymphocytes in five out of six sheep synthesized IFN-γ (an indicator of T-cell activation) 10–30 h. after challenge, whereas none was synthesised by efferent lymphocytes until 4–11 days after infection when production was intermittent and variable. Both afferent (five out of six) and efferent (six out of seven) lymph plasmas contained IFN-γ at 10–30 h. but none was found in efferent lymph after 30 h. Colony stimulating activity (an indicator of immunoinflammatory responses) in both lymph compartments was biphasic peaking at 10–30 h. with a later peak which coincided with a lymphoblast response. The results are consistent with an early memory T-cell response in the dermis and afferent lymph followed by recruitment of antigen-specific lymphocytes from the blood, and activation within the node. Résumé— Après infection dermique de noutons préalablement sensibilisés ail virus de l'ecthyma contagieux, des differences de phénotype cellulaire et de cinétique ont été observés entre le flux lymphotique afférent au ganglion local et la lymphe quittant le ganglion. Les lymphocytes afférents chez cinq des six moutons synthétisaient de l'IFNγà 10–30 h mais aucun n'a été retrouvé dans la lymphe efférente à 30 h. L'activité de stimulation de colonie (un indicateur des réponses immunoinflammatoires) dans les deux compartiments lymphatiques suivait deux pics à 10 et 30 h avec un dernier pic qui coïncidait avec la réponse lymphoblastique. Les résultats sont compatibles avec une réponse précoce de cellules T mémoire dans le derme et les lymphatiques afférents suivie par le recrutement de lymphocytes spécifiques de l'antigène dans le sang, et leur activation dans les ganglions. Zusammenfassung— Nach einer dermalen Infektion von vorber sensibilisierten Schafen mit Orf Virus konnten Unterschiede im Zell Phänotyp und in der Kinetik der afferenten Lymphe (in den örtlichen Lymphknoten fließend) gegenüber der efferenten Lymphe (aus dem Lymphknoten abfließend) gemessen werden. Die afferenten Lymphozyten synthetisierten bei 5 von 6 Schafen IFN-y (ein Indikator der T-Zell Aktivierung) 10 bis 30 Stunden nach der Infektion, während keines von der efferenten Lymphozyten synthetisiert wurde; erst 4 bis 11 Tage nach der Infektion zeigte sich eine intermittierende und variable Produktion. Sowohl bie 5 von 6 afferenten wie bei 6 von 7 efferenten Proben enthielt das Lymphplasma IFN-y nach 10 bis 30 Studen, aber keines in den efferenten Proben nach 30 Studen. Die “Kolonie-stimulierende Akrivität” als ein Indikator für Immuminflammatorische Reaktionen zeigte in beiden Lympharten einen zweiphasigen Peak nach 10 bis 30 Stunden, wobei der spätere Peak mit der Lymphoblastenreaktion zusdammen fiel. Diese Ergebnisse sprechen für eine frühe Reaktion der Memory-T-Zellen in der Dermis und der afferenten Lymphe mit anschließender Rekrutierung Antigen-spezifischer Lymphozyten aus dem Blut und Aktivierung innerhalb des Lymphknotens. Resumen Después de la infección dérmica de ovejas previamente sensibilizadas con el virus Orf, se obsevaron las diferencias en el fenotipo y quinética celular de de los nódolus aferentes que desembocaban en los nódulos locales, comparados con los de tipo eferente. Los linfocitos aferentes de 5/6 ovejas sintetizaron IFN-y, (un indicador de la activación de los linfocitos T), después de 10–30 horas, pero no se encontró alguno en los linfocitos eferentes hasta los días 4–11 después de la infección, cuando la producción era intermitente y variable. Ambos plasmas linfocíticos, aferente (5/6) y eferente (6/7), contenían IFN-y a las 10–30 horas, pero no se encontró alguno en los eferentes hasta después de las 30 horas. En ambos compartimentos linfáticos la actividad estimulante de la colonia, (un indicador de respuesta inmunoinflamatoria), presentó un máximo de tipo bifásico a las 10–30 horas con otro máximo tardío, que coincidió con la respuesta de tipo linfoblástico. Los resultados corresponden con una respuesta de los linfocitos T de memora temprana en la dermis y los nódulos linfáticos aferentes, seguidos por un flujo de linfocitos antígeno-específicos procedentes de la sangre y activación dentro del nódulo linfático.  相似文献   
42.
Recruitment fisheries oceanography studies the impact of the environment on the annual production of young to fished populations (finfish as well as invertebrates). Interannual variation in recruitment is the most important source of biological variability facing fisheries managers. Because most variation in recruitment occurs during early, mainly planktonic stages, recruitment fisheries oceanography usually integrates studies of plankton and physical oceanography. The concepts upon which these studies rest were first expressed in the late 1800s by Spencer Fullerton Baird, the first Commissioner of the US Commission of Fish and Fisheries. These concepts appear to have been independently developed by Johan Hjort and others in northern Europe in the early 1900s, and brought back to the United States through contacts between Hjort and Henry Bryant Bigelow, who passed the ideas to his students at Harvard University, including Lionel Albert Walford and Oscar Elton Sette. Although both Walford and Sette did their initial work in recruitment fisheries oceanography off the US east coast, as federal fisheries scientists, they were sent to California in response to the decline of the sardine fishery, where they incorporated the ideas of Hjort into the programme that has become the California Cooperative Oceanic Fisheries Investigations (CalCOFI). The original plan for CalCOFI research was to provide a test of Hjort's ideas. Scientists working with CalCOFI implemented this plan and conducted subsequent research that had its roots in the ideas expressed by Baird. This research was in marked contrast to the fishery-yield orientation of most fisheries research that was being conducted at the time on the west coast of North America, under the dominating influence of William Francis Thompson. In recent years, federal fisheries programmes have investigated recruitment processes of a number of other fish stocks, and considerable effort has been expended toward refining the conceptual framework beyond the hypotheses of Hjort. This paper expands on this history, making note of scientists who were particularly important in the evolution of this discipline. We conclude that although recruitment fisheries oceanography has become a well-established field of study, and many technological advances have been made, the recruitment process is still not well understood and fluctuations in year-class abundance remain a major source of uncertainty in managing marine fisheries.  相似文献   
43.
Partial maxillectomies were performed in 17 dogs and three cats to accomplish wide excision of oral tumors. The extent of the maxillectomy was dependent on tumor type, location, size, and invasiveness as determined by clinical and radiographic examination and incisional biopsy. The tumor and involved portions of adjacent facial bones, most commonly the maxillary and incisive bones, were removed. The resulting oronasal defect was closed by suturing a labial mucosal flap based on the lip margin to the hard palate mucoperiosteum. The major postoperative complication was partial suture line dehiscence, which occurred in three dogs. All four dogs with benign tumors were free of disease 7 to 34 months postoperatively (median 21.5 months). Of the 13 dogs treated for malignant neoplasia, seven were tumor-free at follow-up times ranging from 3 to 31 months (median 12 months). Five dogs with malignant tumors developed local recurrence 1 week to 10 months postoperatively (median 4.5 months). One cat with a benign tumor and two with malignant tumors were tumor-free at follow-up times of 7, 24, and 27 months. Partial maxillectomy can be effective in treating both benign and malignant oral tumors in dogs and cats.  相似文献   
44.
Objectives— To report a technique for arthrodesis of the distal interphalangeal joint (DIPJ) with two 6.5 mm Acutrak Plus (AP) compression screws from a solar approach and outcome in 7 cattle.
Study Design— Case series.
Animals— Cattle (n=7) with DIPJ arthritis.
Methods— Retrieved data from medical records of cattle that had undergone DIPJ arthrodesis using 2 AP screws via a solar approach were signalment, history, clinical signs, preoperative blood work, preoperative radiographs, complications, postoperative radiographs, and postoperative lameness evaluation. Outcomes, assessed by owner interview 6–26 months after surgery, were classified as excellent, good, or poor.
Results— Fusion of the DIPJ was evident by 6 months. All cattle returned to full function with minimal lameness and normal appearance to the distal aspect of the limb. Four thoracic limbs and 3 pelvic limbs were affected; 3 medial and 4 lateral claws. Complications included moderate lameness associated with implants (n=2) that resolved after screw removal.
Clinical Relevance— Use of the AP screw system in cattle is an excellent option for DIPJ arthrodesis with minimal postoperative morbidity and excellent return to function.  相似文献   
45.
The effects of surgical and nonsurgical therapy on the development of osteoarthritis were compared in 12 dogs with bilateral medial patellar luxation and unilateral surgical repair. Evaluations included severity of lameness and patellar luxation, ligamentous stability, range of motion, and radiographic evidence of osteoarthritis before surgery and at a mean of 33 months after surgery. Stifles without surgical treatment served as controls for the contralateral stifles with surgery. All stifles treated surgically had reduced patellofemoral joints, normal range of motion, and improved limb use. Osteoarthritis progressed significantly and comparably in both groups of stifles. Progression of osteoarthritis was not correlated with luxation grade, body weight, or interval from surgery to follow-up. Age at surgery was correlated positively with severity of osteoarthritis in the stifles treated surgically.  相似文献   
46.
The biomechanical characteristics of a 4-ring circular multiplanar fixator applied to equine third metacarpal bones with a 5 mm mid-diaphyseal osteotomy gap were studied. Smooth Steinmann pins, either 1/8 inch, 3/16 inch, or 1/4 inch, were driven through pilot holes in the bone in a crossed configuration and full pin fashion and fastened to the fixator rings using cannulated fixation bolts. The third metacarpal bone fixator constructs were tested in three different modes (cranial-caudal four-point bending, axial compression, and torsion). Loads of 2,000 N were applied in bending and axial compression tests and a load of 50 N ± m was applied during testing in torsion. Fixator stiffness was determined by the slope of the load displacement curves. Three constructs for each pin size were tested in each mode. Comparisons between axial stiffness, bending stiffness, and torsional stiffness for each of the three different pin sizes were made using one-way analysis of variance. There was no visually apparent deformation or permanent damage to the fixator frame, and no third metacarpal bone failure in any of the tests. Plastic deformation occurred in the 1/8 inch pins during bending, compression, and torsion testing. The 3/16 inch and 1/4 inch pins elastically deformed in all testing modes. Mean (±SE) axial compressive stiffness for the 1/8 inch, 3/16 inch, and 1/4 inch pin fixator constructs was: 182 ± 16 N/mm, 397 ± 21 N/mm, and 566 ± 8.7 N/mm; bending stiffness was 106 ± 3.3 N/mm, 410 ± 21 N/mm, and 548 ± 12 N/mm; and torsional stiffness was 6.15 ± 0.82 N.m/degree, 7.14 ± 0.0 N±m/degree, and 11.9 ± 1.0 N.m/degree respectively. For statically applied loads our results would indicate that a 4-ring fixator using two 1/4 inch pins per ring may not be stiff enough for repair of an unstable third metacarpal bone fracture in a 450 kg horse.  相似文献   
47.
Percutaneous nephrostomies (PN) were created with teflon fascial dilators under fluoroscopic guidance, to implant stones bilaterally into the renal pelves of five dogs weighing 7 to 35 kg. Between one and seven stones of 0.25 to 1.00 cm diameter were implanted into each renal pelvis. Two to 4 weeks later, PN tracts were recreated, and the implanted renal stones were successfully removed under fluoroscopic and endoscopic visualization. Results of gross and histopathologic evaluation of the kidneys 2, 7, 14, 30, and 90 days after stone removal showed minimal, localized renal parenchymal trauma. Complications, although infrequent, included proximal ureteral tears and hemorrhage. Difficulty was encountered in maneuvering equipment around large or numerous stones. Canine percutaneous nephrolithotomy was successful despite great variation in kidney size, as well as variations in the number, size, and shape of stones in the upper urinary tract.  相似文献   
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50.
Gastric dilatation-volvulus (GDV) was created experimentally and maintained for 90 minutes in 16 anesthetized, mixed-breed dogs. After the GDV was corrected, normal saline solution (0.044 mL/kg intravenously [IV]) was administered to eight dogs (controls), and flunixin meglumine (2.2 mg/kg IV) was administered to eight dogs. Microspheres labeled with radioactive cobalt, scandium, tin, or niobium were injected intravenously at baseline (before GDV) and minutes 90, 100, and 270, respectively, to determine tissue blood flows. Plasma endotoxin and prostacyclin were measured at the same intervals. Electrocardiogram, mean arterial pressure, portal pressure, and cardiac output were recorded continuously. Dogs were euthanatized at minute 270 and necropsied. There was no significant difference between treatment groups for any measured variable at any time. Endotoxin levels increased significantly during GDV. Prostacyclin levels were lower in dogs treated with flunixin meglumine than in controls at minutes 210 and 270. Histopathologic findings were similar for all dogs and consistent with those associated with endotoxemia. Flunixin meglumine treatment did not alter cardiac indices or tissue blood flows significantly. However, elevation of prostacyclin was inhibited by flunixin meglumine, which suggested that continued effects of endotoxic damage might be attenuated or inhibited.  相似文献   
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