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901.
Five young Shiloh Shepherd Dogs (4 males and 1 female) related by a common sire were studied because of progressive pelvic limb weakness and incoordination. All dogs had a spastic paraparesis and pelvic limb ataxia consistent with an upper motor neuron and general proprioceptive lesion between spinal cord segments T3 and L3. Proliferative lesions involving one or more of the articular processes from the 11th thoracic vertebrae to the 2nd lumbar vertebra were observed on radiographs of the thoracolumbar vertebrae. Dorsal compression of the spinal cord was identified during imaging studies at these sites. Abnormalities of the synovial joints and bony proliferation of the involved articular processes were identified at postmortem examination in 2 dogs. The articular processes and associated vertebral arches protruded into the vertebral canal, indenting the dorsal surface of the spinalcord. Degenerative joint disease (DJD) was identified histologically. A compressive myelopathy was diagnosed in the spinal cord. These dogs were affected by a compressive myelopathy as a consequence of vertebral process DJD that likely has a geneticcomponent. The DJD could have been caused by a primary vertebral malformation or an injury to the processes at a young age causing malarticulation.  相似文献   
902.
蜂胶对糖尿病大鼠肾脏的影响   总被引:3,自引:0,他引:3  
将复制糖尿病模型的72只SD大鼠随机分为模型组、蜂胶水提液低剂量组(WSP1),蜂胶水提液高剂量组(WSP2)、蜂胶醇提液低剂量组(EEP1)、蜂胶醇提液高剂量组(EEP2)和阳性对照组,另取12只为正常组.除正常组和模型组外,各组分别给予不同的试验药物.给药7周后,抽血测生化指标,同时取肾脏,计算肾脏/体重.结果发现蜂胶能降低糖尿病大鼠的尿酸、尿素、肌酐水平,并且蜂胶给药组大鼠的肾重/体重均比模型组低,表明蜂胶对糖尿病机体内的肾脏组织具有保护作用.  相似文献   
903.
AIM: To investigate the change of Cpn60 content, the alterations of pancreatic enzymes and lysosome, in order to better understand the mechanism of intrapancreatic enzyme activation in acute pancreatitis(AP). METHODS: The AP model was replicated by retrograde infusion of 4% sodium-deoxycholate in the choledocus of SD rats. The levels of amylase in plasma and TNF-α in pancreatic tissue were measured by biochemical technique at 5 h and 10 h after AP induction. The content of Cpn60 and pancreatic enzymes in different compartments of the acinar cells were tested by quantitative protein A-gold immunocytochemistry technique. The change of lysosome in the acinar cells was observed under the electronic microscope. RESULTS: After AP was induced, the levels of amylase in the plasma and TNF-α in the pancreatic tissue increased significantly. Lysosomes with different forms were found inside the acinar cells, and some of them located in the Golgi apparatus. Cpn60 content decreased, which was accompanied by an increase of lipase or chymotrypsinogen content in the pancreatic secretory pathway. CONCLUSION:In the pancreatic acinarcells of AP rats,Cpn60 content decreased,suggesting an insufficient chaperone capacity,and combining with the change of lysosome both in its amount and locat ion,which may take part in the intrapancreatic enzyme activation and the development of AP.  相似文献   
904.
AIM: To observe free radicals (MDA, NO) and iNOS of patients with severe acute respiratory syndrome (SARS) and to explore its significance. METHODS: MDA, NO2-/NO3- and iNOS were determined in SARS patients during the early, recovery and follow-up stage, front doctors and nurses (contact group) and health people (health control). RESULTS: The level of MDA during first stage was higher than that of recovery stage and the MDA level of recovery stage was higher than that of follow-up stage, contact group, and health control group (P<0.01). The content of NO2-/NO3- during early stage was higher than that of other groups, and the NO2-/NO3- contents of recovery stage, follow-up stage were higher than that of contact group and health control group (P<0.01), respectively. The mean of iNOS during early stage was highest than that of other stages (P<0.01) and the mean of recovery stage was higher than that of contact group (P<0.05), there were no difference in iNOS activity among any other groups (P>0.05). CONCLUSION: The pathological injury in pathogenesis of SARS is related to free radicals.  相似文献   
905.
香蕉果实贮藏冷害与PAL活性及可溶性蛋白的关系   总被引:8,自引:0,他引:8  
王勇  谢会  张昭其  陆旺金 《果树学报》2004,21(2):149-152
研究了200μmol/L脱落酸(ABA)和5mmol/L腐胺(Put)处理对贮藏于8℃下条件的香蕉果实耐冷性的影响及其与PAL活性及可溶性蛋白的关系。结果表明:与对照果实相比较,ABA和Put两种处理都不同程度地减轻香蕉果实贮于8℃条件下的冷害。具体表现在,两种处理均延缓了果皮颜色变暗与细胞膜透性的升高,提高了果皮可溶性蛋白含量,维持果实果皮较高的PAL活性。本文还讨论了香蕉果实耐冷性与果皮PAL活性的关系。  相似文献   
906.
The case details and outcome after surgical decompression of 46 dogs with thoracolumbar intervertebral disc disease with loss of deep pain perception prior to surgery were reviewed. Nineteen dogs (41.3%) recovered with a median follow-up period of 12.5 months. Recovery was defined as an ambulatory paraparesis, or better, with urinary and fecal continence. There was a better outcome in dogs with loss of deep pain for less than 24 hours prior to surgery (19/41; 46.3% recovered) than in dogs without deep pain perception for more than 24 hours (0/5; 0% recovered). Dogs with deep pain perception present at two weeks postoperatively had significantly higher success rate (8/12; 66.7% recovered) than dogs without deep pain perception at this time period (1/10; 10.0% recovered). The return of deep pain perception by two weeks postoperatively can be a useful positive prognostic indicator.  相似文献   
907.
引种扁桃抗寒力及冻害成因分析   总被引:1,自引:0,他引:1  
通过对两个引种扁桃扶兹(Fritz)和那普瑞尔(Nonpareil)1年生枝条的半致死温度(LT50)拟合、越冬调查、休眠期的含水率及其解刨结构的分析,对扁桃的抗寒力进行了研究,结果表明:Fritz、Nonpareil及CK 1年生休眠枝的半致死温度(LT50)分别为-24.88℃、-20.56℃和-17.15℃;冻害指数分别为10%、45%和87%,抗冻害评级依次为高抗、中抗、易抽。因此,两供试品种都有较强的抗寒能力,而且均强于CK,Fritz的抗寒能力最强。造成1年生枝条冻害的主要原因是生长与休眠临界期枝条的大量失水;其形态解剖学原因是表皮薄,皮层薄壁细胞排列疏松和韧皮薄壁细胞不发达。  相似文献   
908.
AIM: To study the effect of acute renal failure (ARF) on the differentiated frequency of Sca-1+ cells from murine fetal liver in irradiated mice. METHODS: The Sca-1+ cells from murine fetal liver were isolated with magnetic cell sorting (MACS) technique, the sex of which was identified by PCR. The 2×104 Sca-1+ cells were transplanted into a lethally irradiated ([60Co], 8 Gy) inbred female mouse. After 8 weeks, these recipient mice were divided to A, B, and C groups at random (A group: irradiated; B group: ARF; C group: ARF and Sca-1+). The mice in B and C groups were induced to ARF with 50% (V/V) glycerin (11.6 mL/kg). 72 hours later, the mice in C group were injected with the fresh prepared Sca-1+ cells again. 8 weeks later, mice were sacrificed, and their kidneys were taken out, fixed and slices were prepared. Fluorescence in situ hybridization (FISH) of renal slices was performed and the pictures of them were taken and analyzed. RESULTS: The cells containing Y chromosome were found in renal slices from the mice in A, B and C groups, which located in epithelial cells of renal tubules, interstitium, glomeruli, and glomerular margin and increased gradually. The double and encircle zone of Y chromosome cells were found in the slices from the mice in B and C groups separately, which was consist of new renal tubules. The differentiation frequency of Sca-1+ cells in kidney in A, B and C groups were (1.65±0.18)%, (8.58±1.34)% and (18.13±1.91)%, respectively, which showed significant difference between former group and later group (P<0.01). CONCLUSION: The differentiation of Sca-1+ cells from murine fetal liver into renal cells and tissue is promoted by physiological microenvironment of acute damage and regeneration.  相似文献   
909.
红菜薹的抗冻性   总被引:2,自引:0,他引:2  
以19份红菜薹材料为试材,将离体叶片组织经过系列冷冻低温处理后测定电导率,进而计算细胞膜伤害率,然后用Logistic方程拟合细胞膜伤害率与温度的关系,求出拐点温度来估计材料的低温致死温度。结果表明:拐点温度能准确估计红菜薹的抗冻性;红菜薹的低温致死温度因材料而异,在-5~-11℃之间;抗冻性与农艺性状的关系表现为越晚熟抗冻能力越强,总莲座叶数越多抗冻能力也越强,同时也有植株越高大抗冻能力越强的趋势。  相似文献   
910.
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