排序方式: 共有55条查询结果,搜索用时 15 毫秒
1.
MAYUMI L. ARIMITSU JOHN F. PIATT MICHAEL A. LITZOW ALISA A. ABOOKIRE MARC D. ROMANO and MARTIN D. ROBARDS 《Fisheries Oceanography》2008,17(2):137-146
Pacific capelin (Mallotus villosus) populations declined dramatically in the Northeastern Pacific following ocean warming after the regime shift of 1977, but little is known about the cause of the decline or the functional relationships between capelin and their environment. We assessed the distribution and abundance of spawning, non‐spawning adult and larval capelin in Glacier Bay, an estuarine fjord system in southeastern Alaska. We used principal components analysis to analyze midwater trawl and beach seine data collected between 1999 and 2004 with respect to oceanographic data and other measures of physical habitat including proximity to tidewater glaciers and potential spawning habitat. Both spawning and non‐spawning adult Pacific capelin were more likely to occur in areas closest to tidewater glaciers, and those areas were distinguished by lower temperature, higher turbidity, higher dissolved oxygen and lower chlorophyll a levels when compared with other areas of the bay. The distribution of larval Pacific capelin was not sensitive to glacial influence. Pre‐spawning females collected farther from tidewater glaciers were at a lower maturity state than those sampled closer to tidewater glaciers, and the geographic variation in the onset of spawning is likely the result of differences in the marine habitat among sub‐areas of Glacier Bay. Proximity to cold water in Glacier Bay may have provided a refuge for capelin during the recent warm years in the Gulf of Alaska. 相似文献
2.
3.
A Modified Cloward''s Technique for Arthrodesis of the Normal Metacarpophalangeal Joint in the Horse
GREGORY R. CRAWLEY DVM MS BARRIE D. GRANT DVM MS DipiomateACVs KARL K. WHITE DVM DipiomateACVs DAVID D. BARBEE DVM MS DiplomateACVR ANTHONY M. GALLINA DVM PhD MARC H. RATZLAFF DVM PhD 《Veterinary surgery : VS》1988,17(3):117-127
A modified Cloward's technique was performed for arthrodesis of one metacarpophalangeal (MCP) joint in eight horses. Dorsal arthrotomies were performed medial and lateral to the common digital extensor tendon and two 16 mm holes were drilled through the joint. A perforated cylindrical stainless steel basket filled with cancellous bone was impacted into each hole. The limbs were supported in casts for 8 weeks. The joints were examined and radiographed at 4 weeks, 8 weeks, 6 months, and 10 months. One horse was euthanatized at week 14 to assess the progress of the arthrodesis. In the other seven horses, there was clinical fusion at month 6. Dynamographic evaluations were performed 11 months after surgery at the walk and trot. The maximum vertical forces exerted during weight bearing by treated and control limbs were compared. No difference was detected at the walk; however, a significant difference was present at the trot (p less than 0.05). It was calculated that at the trot the horses placed 90% as much force on the treated limb as on the control limb. Eleven months after surgery, the baskets contained compact and cancellous bone. Ingrowth of bone occurred through all openings, completely filling the baskets and fusing the joints. 相似文献
4.
5.
KENNETH E. BARTELS dvm MS ROGER C. PENWICK VMD LYN J. FREEMAN dvm RICHARD L. LOWERY PhD TOM ALEXANDER BS KENT APPLEMAN BS CATHRYN BLOUNT BS 《Veterinary surgery : VS》1985,14(4):310-318
Eight synthetic casting materials were evaluated with respect to tensile and fatigue strengths, exothermicity (evolution of heat during polymerization), permeability (porosity), radiolucency, and cost. Strength determination for a five-layer sample included measurement of the ultimate load at which a material failed, the ability to absorb energy, and the stiffness a material possessed after application of a cyclic stress. Results indicated that Vet Cast was superior with respect to tensile and fatigue strengths. The exothermic reaction associated with the "curing" or polymerization process was evaluated and not considered excessive although Ultra Cast attained a temperature of 48.0°C and was uncomfortable to handle during application. Permeability was determined. Delta Lite and Hexcelite NS were the most permeable materials and dried more rapidly and thoroughly after immersion than the other casting materials. Hexcelite NS was considered the least radiolucent material and was the most expensive material studied. Each of the synthetic casting materials demonstrated superiority in one or more of the categories tested. No one product demonstrated consistent superiority in criteria appropriate for clinical application. 相似文献
6.
湿地植物具有强大的通气组织和根部渗氧能力特征,使得其根际微环境处于氧化状态从而适应湿地土壤浸水的环境。近年来,湿地植物通气组织和渗氧在重金属吸收和耐性研究方面已引起了人们的关注,并对此进行了相关的研究。本文分别对湿地植物通气组织和渗氧特征,通气组织和渗氧对重金属吸收和耐性影响、对根际微环境影响等方面的研究进展和存在问题进行了综述,并提出了该领域未来可能的研究方向。认为针对从通气组织和渗氧角度出发研究湿地植物重金属耐性机理,应重点对湿地植物根际重金属的环境化学行为展开深入研究,在研究方法和手段上应注重新技术的开发与应用。 相似文献
7.
MARIE DE SWARTE KATE ALEXANDER BENOIT RANNOU MARC‐ANDRE D'ANJOU LAURENT BLOND GUY BEAUCHAMP 《Veterinary radiology & ultrasound》2011,52(4):451-456
The differentiation of benign vs. neoplastic lymph nodes impacts patient management. Specific sonographic features are typically considered when assessing lymph nodes in dogs. However, the usefulness of these criteria in distinguishing benign vs. malignant lymph nodes remains largely unknown, especially for deep lymph nodes. Our aim was to compare sonographic features in benign and neoplastic deep lymph nodes with the hope of identifying predictive criteria. Thirty‐one deep lymph nodes (16 mesenteric, 10 medial iliac, three hepatic, one sternal, and one cranial mediastinal) in 31 dogs were examined prospectively with B‐mode and Color flow Doppler. Lymph nodes were aspirated using ultrasound‐guidance and final diagnosis were established based on cytologic and/or histopathologic interpretation. Prevalence of each sonographic feature and combinations of two features was calculated for each group and compared using a χ2‐test or Student's t‐test for unequal variances. Ten lymph nodes were benign (hyperplastic and/or inflammatory) and 21 were neoplastic. All were hypoechoic, except for one neoplastic lymph node. Maximal short‐axis diameter (P=0.0006) and long‐axis diameter (P=0.01), and SA/LA ratio (P=0.008) were increased significantly for neoplastic (2.8, 5.5 cm, and 0.50, respectively) vs. benign (1.2, 3.8 cm, and 0.34, respectively) lymph nodes. The prevalence of other features was similar between groups. Doppler evaluation was possible in 77% of lymph nodes, but there was no significant difference between groups. When any two ultrasound features were combined, the only difference between benign and neoplastic lymph nodes was for the combination of contour regularity and appearance of the perinodal fat (P=0.03). 相似文献
8.
A. B. LLOYD B.Sc. Ph.D. R. B. CUMMING B.V.Sc. Ph.D. R. D. KENT 《Australian veterinary journal》1977,53(2):82-87
Day-old chickens or turkey poults when pretreated with an oral dose of intestinal fluid froma healthy adult bird, were considerably more resistant to the subsequent establishment of Salmonella typhimurium in their intestinal tract than were non-treated chickens or turkey poults. Caecal fluid was more effective as a pretreatment than were washings taken from other parts of the gastro-intestinal tract of a healthy adult bird. This increased resistance of pretreated chickens or poults is thought to result from the rapid establishment of a conventional indigenous microflora which inhabits establishment and growth by the invading enteric pathogen. 相似文献
9.
PAMELA C. WAGNER M.S. D.V.M. GEORGE W. BAGBY M.D. § BARRIE D. GRANT D.V.M. M.S. ANTHONY GALLINA D.V.M. PH.D. † MARC RATZLAFF D.V.M. PH.D. ‡ RON SANDE D.V.M. PH.D. 《Veterinary surgery : VS》1979,8(1):7-12
The Cloward technique for intervertebral fusion was utilized on 12 horses ranging from 3 months to 2 years of age. Of the 12 horses, 9 had been diagnosed as having equine cervical vertebral malformation (CVM) or "wobbles," and 3 were normal controls. A large hole was drilled from the ventral border of the vertebral bodies spanning the intervertebral disc and the vertebral end plates of the 2 articulating vertebrae. Frozen homologous bone dowels of slightly larger diameter from equine cadaver ilia were inserted in the holes. No adverse postoperative complication arose. Clinical improvement was seen in all horses with CVM. Three months postoperatively, partial or complete fusion was evident radiographically in 11 of the 12 horses. Necropsies were performed 3–6 months postoperatively to evaluate the quality of the fusion. Cadaver manipulation demonstrated reduced intervertebral movement at the operative site in all cases. The articulations of the equine cervical spine can be operatively fused by the Cloward technique, and surgically induced trauma is minimal. This technique can be used for stabilizing subluxations and may be applicable for treating fractures and osteolytic processes that have weakened vertebrae. 相似文献
10.
ANNE CAROLE DUCONSEILLE ARNAUD LOUVET PATRICK LAZARD SUZY VALENTIN MARC MOLHO 《Veterinary radiology & ultrasound》2010,51(1):52-56
Retrocaval ureter and transposition of the caudal vena cava are each, rare developmental anomalies. We describe the usefulness of static fluid magnetic resonance urography and dynamic contrast-enhanced magnetic resonance urography in the diagnosis of these anomalies. Basic techniques, benefits, and drawbacks of magnetic resonance urography are presented. 相似文献