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41.
Susan L. Kraft DVM PhD John M. Mussman DVM Thomas Smith DVM MS David S. Biller DVM James J. Hoskinson DVM 《Veterinary radiology & ultrasound》1998,39(1):9-13
A three-year-old male Boxer dog had hyperesthesia, symmetrical epaxial, gluteal and hind limb muscular atrophy and rear limb ataxia. Neurological deficits included decreased conscious proprioception of the left hind limb, decreased withdrawal and increased patellar reflexes of both hind limbs. The dog had a urinary tract infection with positive culture for Staphylococcus intermedius. On survey radiography of the lumbosacral spine there was active bone proliferation spanning the L7 S1 intervertebral disc space with an epidural filling defect at the ventral aspect of the vertebral canal on epidurography, On magnetic resonance imaging (MRI), findings were similar to those described for human diskospondylitis including altered signal intensity and nonuniform contrast enhancement of the L7-S1 intervertebral disc, adjacent vertebral end plates and epidural and sublumbar soft tissues. Although skeletal radiography is usually sufficient to reach a diagnosis of discospondylitis, MRI of this patient made it possible to reach a presumptive diagnosia of discospondyltis prior to development of definitive radiographic abnormalties. 相似文献
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为实现植物生命需水状况的无损检测,通过定量辨识植物叶态萎蔫特征反映植物亏水胁迫状况,基于分形理论"双毯法"定义了萎蔫指数LDBM,利用基于激光三角原理的三维激光扫描仪获取植物叶片表型点云数据,以西葫芦、秋葵、葫芦、南瓜4种植物为研究对象,结合饱和水汽压差与光合有效辐射2种微环境参数,进行了植物叶态萎蔫定量辨识研究。试验分析了4种植物萎蔫指数LDBM的日变化曲线,证明LDBM用于表征叶态萎蔫状况是合理和可行的;分析了萎蔫指数LDBM与微环境参数的相关性,4种植物LDBM与饱和水汽压差相关系数均大于0.81,与光合有效辐射相关系数均大于0.71,与2种参数都有很强的正相关性;并且与基于离散时域傅里叶变换定义的萎蔫指数L2DFT进行了对比,LDBM与L2DFT呈负相关性,4种植物的相关系数均大于0.82,表明LDBM能够准确地定量表征叶态萎蔫。 相似文献
43.
Siegfried Schittenhelm Tina Langkamp-Wedde Martin Kraft Lorenz Kottmann Katja Matschiner 《Journal of Agronomy and Crop Science》2020,206(6):722-733
To examine the extent to which heat stress during grain filling impacts on the development and yield of winter wheat (Triticum aestivum L.), a 3-year field experiment was conducted on a loess soil with high water holding capacity in the North German Plain. Thirty-two mostly European winter wheat cultivars were exposed to heat stress in a mobile foil tunnel with maximum air temperatures of 45.7, 45.4, and 47.2°C in 2015, 2016, and 2017, respectively. The 14-day post-anthesis heat stress treatment caused an average 57.3% grain yield reduction compared to a close-by non-stressed control. The proportion of green crop area after the heat stress phase varied from 7% to 98% in 2016 and from 37% to 94% in 2017. The green crop area percentage did not significantly correlate with grain yield, indicating that the delayed senescence of stay-green phenotypes offers no yield advantage under terminal heat stress. The water soluble carbohydrate (WSC) concentration of the stems at crop maturity varied between 6 and 92 g/kg dry matter, showing that the genotypes differed in their efficiency at using the stem carbohydrate reserves for grain filling under heat stress. The stem WSC concentration correlated positively with the beginning of anthesis (r = 0.704; p < .001) but negatively with the grain yield (r = −0.431; p < .05). For heat tolerance breeding, the stem reserve strategy, i. e. the rapid and full exhaustion of the temporary carbohydrate storage therefore seems more promising than the stay-green strategy. 相似文献
44.
Indications for bronchoscopy, the equipment and technique performance in dogs and cats are presented. The method is invasive, therefore exact indications such as chronic cough of noncardial origin, foreign bodies, parasitic invasion, paralysis of the larynx or tumours are required. Bronchoscopy enables the surgeon to take samples of bronchial discharge. 相似文献
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Tucker DW Olsen D Kraft SL Andrews GA Gray AP 《Journal of the American Animal Hospital Association》2000,36(2):163-167
An eight-year-old, male castrated bullmastiff presented to the Kansas State University Veterinary Medical Teaching Hospital with left hind-limb paralysis. A mass was identified in the left paralumbar soft tissue adjacent to the fourth (L4) to sixth (L6) lumbar vertebrae by magnetic resonance imaging. The iliopsoas muscle contained the mass which was identified as a hemangiosarcoma on histopathological examination. Hemangiosarcoma is rarely reported as a primary tumor arising from muscle vascular endothelium. 相似文献