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61.
Anim Boanyo?DansohEmail author Akio?Koizumi Takuro?Hirai 《Journal of Wood Science》2003,49(5):405-410
A study was undertaken to evaluate the effect of glue application and placement of butt-joints on the compressive and tensile properties in a butt-jointed lamination. The aim was to provide background information for producing butt-jointed, glued, laminated timber. Three butt-jointed lamination models were prepared from spruce-pine-fir (S-P-F) dimension lumber with glued and nonglued butt joints, with different placements of the butt joints in the models. The axial stiffness and strength properties were assessed using both compressive and tensile tests. The results of the study indicated that for the compressive lamination model the application of glue at the butt joint gave more stiffness than the nonglued butt joint. Neither glue application nor placement of the joint had a statistically significant effect on the compressive strength. There were no significant differences between the glued and nonglued butt joint for either tensile strength or stiffness. 相似文献
62.
GROSS AND HISTOPATHOLOGIC CORRELATION OF LOW‐FIELD MAGNETIC RESONANCE IMAGING FINDINGS IN THE STIFLE OF ASYMPTOMATIC HORSES
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Marcos P. Santos Santiago D. Gutierrez‐Nibeyro Alexia L. McKnight Kuldeep Singh 《Veterinary radiology & ultrasound》2015,56(4):407-416
With the recent introduction of a 0.25T rotating MRI system, clinical evaluation of the equine stifle joint is now possible in the average equine athlete. A recent publication described common abnormalities of horses with stifle lameness detected with a low‐field MRI system; however, postmortem corroboration of the lesions detected was not possible. Therefore, our objective was to compare postmortem findings with low‐field MRI findings in equine cadaver stifle joints. Ten fresh cadaver stifle joints from horses without clinical signs of stifle disease were evaluated using low‐field MRI, gross dissection, and histopathology. In eight stifles, either the lateral or medial cranial meniscotibial ligament had an irregular shape, fiber separation, or moderate abnormal signal intensity (SI) on all sequences. In five stifles, the medial femoral condyle had articular cartilage fibrillation with or without an osteochondral defect over the weight bearing surface of the medial femoral condyle. All stifles had abnormal SI on all sequences within the patellar ligaments that corresponded with adipose tissue infiltrating between the collagen bundles. Other abnormalities identified included articular cartilage fibrillation of the tibial condyles in three stifles, and articular cartilage fibrillation with chondral defects in the patella in three stifles. All abnormalities detected with low‐field MRI were corroborated by gross dissection. Findings from the current study supported the use of low‐field MRI for detection of stifle joint lesions in horses and demonstrated that some stifle joint pathologies may be subclinical in horses. 相似文献
63.
为方便监测水质与水下鱼群活动,本研究设计了一款面向全水域实时监测的水产养殖机器鱼,并搭建了机器鱼控制系统,开展了机器鱼三维路径跟踪控制研究。在Serret-Frenet坐标系下建立了机器鱼三维空间路径跟踪误差模型,并基于LOS制导律和李雅普诺夫理论设计了一种模糊滑模控制器,最后利用Matlab仿真对本研究提出的控制算法的有效性进行验证。仿真结果表明:所设计的控制器能使机器鱼在模型参数不确定性、外部干扰未知的情况下实现三维路径跟踪控制,其控制精度和鲁棒性明显优于常规PID与滑模控制器。 相似文献
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67.
Detection of Clinically Relevant Pain Relief in Cats with Degenerative Joint Disease Associated Pain
M.E. Gruen E. Griffith A. Thomson W. Simpson B.D.X. Lascelles 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2014,28(2):346-350
Background
Detection of clinically relevant pain relief in cats with degenerative joint disease (DJD) is complicated by a lack of validated outcome measures and a placebo effect.Hypothesis/Objectives
To evaluate a novel approach for detection of pain relief in cats with DJD.Animals
Fifty‐eight client‐owned cats.Methods
Prospective, double‐masked, placebo‐controlled, stratified, randomized, clinical study. Enrolled cats were 6–21 years of age, with owner‐observed mobility impairment, evidence of pain in at least 2 joints during orthopedic examination, and overlapping radiographic evidence of DJD, and underwent a 2‐week baseline period, 3‐week treatment period with placebo or meloxicam, and 3‐week masked washout period. Outcome measures were evaluated at days 0, 15, 36, and 57.Results
Both groups significantly improved after the treatment period (day 36) on client‐specific outcome measures (CSOM) and feline musculoskeletal pain index (FMPI) (P < .0001 for both); there was no difference between the groups on CSOM or FMPI score improvement. After the masked washout period, more cats that received meloxicam during the treatment period had a clinically relevant decrease in CSOM score (P = .048) and FMPI score (P = .021) than cats that received placebo.Conclusions and Clinical Importance
Using both a client‐specific and a general clinical metrology instrument, owners of cats with DJD were able to detect evident recurrence of clinical signs after withdrawal of active medication than after withdrawal of placebo, and that this study design might be a novel and useful way to circumvent the placebo effect and detect the efficacy of pain‐relieving medications. 相似文献68.
69.
为了探索人工圆韧带植入术治疗犬髋关节脱位远期疗效降低的解决办法,选择体重6.5 kg~7.5 kg、年龄1岁左右的3只本地家犬,在使用外科丝线替代圆韧带植入髋关节后,使用医用骨水泥填充和封闭髋臼和股骨孔道,术后通过运动姿态观察、负重力测试、常规 X 线摄片、血清生化项目检测和病理剖检几个方面,分析评估人工圆韧带植入术使用医用骨水泥的效果。结果显示,随着犬肢运动状态逐渐改善,术肢负重力增加;但随着丝线断开或出现退行性关节病,术肢运动肢势改变和负重力降低;骨水泥填充、封闭人工圆韧带孔道效果可靠,关节滑液保持良好,血清重要生化指标均在参考范围。在动物试验基础上,选择医用人工韧带植入和将骨水泥用于犬髋关节脱位临床病例1例,经过9个月的动态观察,术肢运动状态、负重力和髋关节 X 线影像与健肢相比无任何异常。动物试验与临床疗效表明,联合使用医用骨水泥和人工韧带能够很好地重建髋关节结构和功能,维持人工圆韧带植入术治疗犬髋关节脱位的远期疗效。 相似文献
70.
J.F. Hawkins L. Couetil M.A. Miller 《Veterinary journal (London, England : 1997)》2014,199(2):275-280
The objective was to evaluate CO2 laser debridement of the cricoarytenoid joint (CAJ) combined with prosthetic laryngoplasty to prevent post-operative loss of arytenoid abduction in seven horses. Horses were assigned to either laser debridement of the left CAJ and laryngoplasty (laser treated, n = 5) or control laryngoplasty (sham, n = 2), and were evaluated with endoscopic examinations and measurement of right to left angle quotients (RLQ) to assess maintenance of arytenoid abduction. The animals were euthanased at intervals after surgery and larynges were harvested for post-mortem testing, including determination of translaryngeal flow, pressure, impedance and RLQ. Measurements were obtained under increasing vacuum-generated negative pressure with laryngoplasty sutures intact and with the knot/crimp of the laryngoplasty sutures removed. Following post-mortem testing the cricoarytenoid joints were examined histologically.Post-operative endoscopic examinations revealed no significant differences between RLQ measurements calculated for day 1 following surgery to the termination date of the study for the seven horses. Post-mortem RLQ at airflows of 10 and 60 L/s was significantly higher in sham than in laser treated horses both before and after knot/crimp removal. Translaryngeal impedance at 10 and 60 L/s was not statistically different between groups. Histopathology revealed necrosis and loss of articular cartilage in the laser treated horses. The lymphoid cell infiltration subsided but joint capsule and periarticular fibrosis increased over the course of the study. Post-operative loss of arytenoid abduction after laryngoplasty can be minimized with CO2 laser debridement of the CAJ joint. 相似文献