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1.
The magnetic resonance (MR) imaging findings of foals with infectious and noninfectious arthritis are described. Six foals with infectious arthritis and three foals with noninfectious arthritis were grouped based on synovial fluid analysis results and examined with radiography and MR imaging. Four out of six foals with infectious arthritis had osseous lesions in MR images indicative of osteomyelitis and only 4/19 lesions were detected on digital radiographs. The three foals with noninfectious arthritis had no osseous lesions in MR images or radiographically. Of the six joints that had osseous lesions detected with MR imaging, three had at least one lytic lesion detected radiographically. Osseous lesions in the epiphysis, metaphysis, and physis appeared in MR images as T2W, short tau inversion recovery, and proton density hyperintense foci with a hypointense halo. The same lesions appeared hyperintense in the 3D RSSG water excitation pulse sequence but lacked a surrounding hypointense halo. Most joints of foals with infectious arthritis had heterogenous signals within the synovial fluid whereas all of the nonseptic joints had homogenous synovial fluid signals. MR imaging appears to be better than radiography in the detection of osseous lesions in foals diagnosed with infectious arthritis and may be a valuable screening test for the presence of osteomyelitis.  相似文献   
2.
Objective— To assess the effect of head position on relative position of the larynx and hyoid apparatus in horses with palatal dysfunction, and to define a standard position for radiographic assessment of laryngeal tie‐forward. Study Design— Prospective clinical study. Animals— Adult horses (n=9) with palatal dysfunction. Methods— Left lateral radiographs of the larynx were obtained pre and postoperatively for 3 different head positions (flexed=90°; neutral=100°; extended=115°). Distance between thyrohyoid bone and thyroid cartilage was measured. Data were analyzed to investigate differences between head positions, and to compare differences between pre‐ and postoperative measurements. Results— Head position had a significant effect on relative position of the larynx and hyoid apparatus preoperatively. There was no significant difference in postoperative measurements of the 3 head positions. A significant difference between pre‐ and postoperative measurements was found with the head in the neutral or extended position whereas there were no significant differences between pre‐ and postoperative measurements using the flexed position. Conclusions— Head position affects the relationship between the hyoid apparatus and larynx preoperatively, with greatest distance occurring when the head is extended. In a flexed position, it is not possible to ascertain whether laryngeal position has changed postoperatively. Clinical Relevance— A standardized head position is necessary when assessing the laryngeal tie‐forward procedure radiographically. An extended head position is most useful for this assessment.  相似文献   
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Invasive species often require mutualistic relationships to successfully invade new environments. Insect pollination is an example of a mutualism that is required for seed-set in the invasive species, Rosa multiflora Thunb. (Rosaceae), an obligate outcrosser. To determine the insect pollinators visiting R. multiflora flowers in Iowa, USA, we collected insects on yellow sticky traps placed on plants during the period of blooming and visually observed insects visiting the flowers. The common insect orders that were collected on the sticky traps included Coleoptera, Diptera, Hemiptera, Hymenoptera, Mecoptera, and Thysanoptera. Many of the insects found on the sticky cards were known to feed on pollen. However, we did not collect Apidae (bumble bees and honey bees) on the sticky cards. We observed Bombus spp. and Apis mellifera foraging on the flowers. Syrphid flies were the most commonly observed taxa visiting the flowers. Our results indicate that R. multiflora is utilizing common generalist insect pollinators in Iowa and that pollination is not a limiting factor for this invasive species.  相似文献   
5.
Rosa multiflora Thunb. (Rosaceae) is an invasive species in the USA, where it grows in pastures and wooded areas. A disease of unknown etiology, rose rosette disease (RRD), infects R. multiflora and other Rosa spp. The goal of this research was to determine the effects of habitat and disease symptoms on the abundance of Phyllocoptes fructiphilus Keifer (Acari: Eriophyidae) , the presumed vector of RRD, and other arthropods on R. multiflora . We collected branch tips from healthy R. multiflora plants growing in the sun and shade, as well as RRD-infected R. multiflora growing in the sun. The samples were collected from June 2002 to April 2004 from three sites in Iowa, USA. The samples were collected approximately every 2 weeks during the summer, monthly during the fall, and once during early spring. The fall samples were only taken from RRD-infected plants because they retain leaves throughout the winter. We found that P. fructiphilus was present on diseased and healthy R. multiflora growing in the sun and on healthy R. multiflora growing as understory plants under a tree canopy (shaded), but the greatest numbers were observed on the diseased plants growing in the sun. Several other mite species, both predatory and phytophagous, Chaetosiphon sp. aphids, and the thrips species, Frankliniella exigua Hood and Neohydatothrips variabilis Beach, occur in the same plant microhabitat as P. fructiphilus . This is the first study to document the presence of additional arthropods in the same microhabitat (branch tips) as P. fructiphilus . Future research needs to isolate and identify the causal agent of RRD so it can be confirmed that, of the many arthropods feeding on R. multiflora , only P. fructiphilus vectors RRD.  相似文献   
6.
Objective— To report clinical signs, diagnostic and surgical or necropsy findings, and outcome in 2 calves with spinal epidural abscess (SEA). Study Design— Clinical report. Animals— Calves (n=2). Methods— Calves had neurologic examination, analysis and antimicrobial culture of cerebrospinal fluid (CSF), vertebral column radiographs, myelography, and in 1 calf, magnetic resonance imaging (MRI). A definitive diagnosis of SEA was confirmed by necropsy in 1 calf and during surgery and histologic examination of vertebral canal tissue in 1 calf. Results— Clinical signs were difficulty in rising, ataxia, fever, apparent spinal pain, hypoesthesia, and paresis/plegia which appeared 15 days before admission. Calf 1 had pelvic limb weakness and difficulty standing and calf 2 had severe ataxia involving both thoracic and pelvic limbs. Extradural spinal cord compression was identified by myelography. SEA suspected in calf 1 with discospondylitis was confirmed at necropsy whereas calf 2 had MRI identification of the lesion and was successfully decompressed by laminectomy and SEA excision. Both calves had peripheral neutrophilia and calf 2 had neutrophilic pleocytosis in CSF. Bacteria were not isolated from CSF, from the surgical site or during necropsy. Calf 2 improved neurologically and had a good long‐term outcome. Conclusion— Good outcome in a calf with SEA was obtained after adequate surgical decompression and antibiotic administration. Clinical Relevance— SEA should be included in the list of possible causes of fever, apparent spinal pain, and signs of myelopathy in calves.  相似文献   
7.
Objective— To determine outcome after medical or surgical treatment of postpartum mares with confirmed or presumptive uterine tears. Study Design— Case series. Methods— Postpartum mares were included if foaling had occurred within 7 days and uterine tear was confirmed surgically or, in medically treated mares, by palpation or presumed based on peritonitis. Information (age, breed; physical examination, laboratory and abdominocentesis findings; treatment, survival rates, length of hospital stay, treatments costs, and breeding performance after discharge) was obtained from the medical records (1990–2007). The influence of variables was compared between medical and surgical treatment, and between survivors and nonsurvivors. Results— For 49 mares, survival was 75%, with no significant difference between medical (11/15; 73%) or surgical (26/34; 76%) treatment. Admission variables, treatment cost, duration of hospital stay, and likelihood of foaling after discharge were not significantly different between treatment groups. Nonsurvivors were significantly more likely to have gastric reflux, higher heart rate, anion gap, lower total CO2, and leukocyte count, compared with survivors. Tears were significantly (P=.018) more likely to occur in the right uterine horn than in other parts of the uterus. Conclusions— Uterine tears occur more commonly in the uterine horns, more so the right horn, and survival is similar with surgical or medical treatment of uterine tears in postpartum mares. Clinical Relevance— Medical treatment may be a reasonable alternative to surgical treatment for uterine tears, although the severity of tear that can resolve with medical treatment is unknown, and medical therapy can be as expensive as surgical treatment.  相似文献   
8.
Surgical management of feline osteoarthritis is currently limited to joint immobilization or amputation. A method of implanting a readily available Swanson Design Silastic finger joint implant in feline stifles was developed and tested in four cats.
The surgical procedure was uncomplicated. The cats ambulated well and resumed normal activities. The joints were stable and retained normal ranges of motion. No undesirable gross pathology resulted from 3 months of implant residence.
We believe that the results of this preliminary study justify investigation of prolonged implant times and clinical trials in arthritic cat stifles.  相似文献   
9.
Biomechanical models that compute the lengths and forces of muscle-tendon units are broadly applicable to the study of factors that promote injury and the planning and effects of orthopedic surgical procedures in equine athletes. A three-dimensional (3D) generic musculoskeletal model of the equine forelimb comprised of bony segment, muscle-tendon, and ligament information, was developed based on high-resolution computed tomographic (CT) and T1-weighted magnetic resonance (MR) images from an isolated forelimb of a Thoroughbred racehorse. Image fusion was achieved through coregistration of CT and MR images with an image analysis program (Analyze) by adjustment of the relative position and orientation of fiducial markers visible in both modalities until the mutual information between the images was maximized. 3D surfaces of the bones and origin/insertion sites, centroid paths and volumes of the muscle-tendon and ligamentous structures were obtained from the multimodal (CT/MR) images using semiautomated and manual segmentation combined with sagittal and transverse color-cryosection anatomic images obtained from three other cadaveric equine forelimbs. Once bony and soft-tissue structures were reconstructed in the same coordinate system, data were imported to a software package for interactive musculoskeletal modeling (SIMM). The combination of integrated CT and MR acquisitions and anatomical images provided an accurate and efficient means of generating a 3D model of the musculoskeletal structures of an average-sized equine adult horse.  相似文献   
10.
Fishery collapses frequently result from combined pressures of the environment and man, which are difficult to discern because of the complexities involved and our limited knowledge. Models to resolve this complexity often become too sophisticated, with too many assumptions and, consequently, with little capacity to predict beyond calibration data. In this paper we implement a different procedure where the model is kept simple and uncertainty accounts for the equation imperfectness to reproduce ecological complexity. Human and environmental forcing on an anchovy ( Engraulis encrasicolus ) stock are simulated with only six parameters plus their error terms, and the uncertainty is computed with Bayesian methods. The simple structure is able to reproduce the major dynamical features of this species in the Gulf of Cádiz, including data on life stages and age structure that had no contact with the model. This is a distinct performance for a frugal approach working on a mid-trophic species and a positive instance where parsimony can simulate the interaction of man, fish and the environment, provided uncertainty is accounted for in the process.  相似文献   
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