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81.
喷雾机器人试验中喷雾幅宽、喷幅边缘的实际轨迹以及重喷漏喷面域不易获得,而且作业时机组的运动状况事后不能重新显示.为此,利用ADAMS软件的动画仿真功能,在ADAMS下使用样条编辑器将试验过程中采集到的机器人和喷雾小车位置数据生成运动轨迹线,让机器人与小车沿此轨迹线运动,显现喷杆运动状况以及喷雾幅宽重喷漏喷区域;同时,利用其后处理模块来获得相邻两喷幅边缘轨迹间距离等参数,便于对其进行定量计算,以此来对作业效果进行评价,并以图形方式输出或以文件形式保存. 相似文献
82.
针对北邮二版(MELINETSⅡ)采访子系统中文图书采购查重存在的问题提出相应的应对技巧与解决策略。 相似文献
83.
Summary Principles of duplication within and between genebank collections have been explored, terminology is proposed and the difficulties
in identifying probable duplication are discussed.
Identical duplication concerns genetically identical accessions, whereas common duplication refers to accessions derived from
the same original population that are mixtures of lines with differing genotype frequencies, or random mating populations
with the same alleles but differing allele frequencies. Partial and compound duplication are types of incomplete duplication.
An additional type of duplication is the relation between the parents in a cross and their offspring, i.e. parental duplication.
Identifying probable duplication on the basis of passport data is often hindered by their incompleteness or poor quality.
The genetic identity of accessions is also subject to changes during maintenance in genebanks. Therefore, probable duplicates
will often not be true duplicates.
Examples from the European Barley Database illustrate the problems. 相似文献
84.
Objective – To describe and review both traditional and newer diagnostic and therapeutic options for canine and feline ureteral obstructions currently being performed clinically in veterinary medicine. Data Sources – A Medline search with no date restrictions was used for this review. Human Data Synthesis – The human literature would support the use of minimally invasive endourological techniques for the treatment of nearly all causes of ureteral obstructions, whenever possible. This typically includes extracorporeal shockwave lithotripsy, intracorporeal lithotripsy via retrograde ureteroscopy or antegrade percutaneous nephroureterolithotomy, ureteral stenting, percutaneous nephrostomy tube placement, and laparoscopic endopyelotomy. Typically open surgery is only suggested in cases of ureteral or gynecological malignancy when en bloc resection is considered a good option, or when various methods of endourological techniques have failed. Veterinary Data Synthesis – The veterinary literature is scarce on the use of interventional endourological techniques for the treatment of ureteral obstructions and has been growing over the last 5 years. The current literature reports the use of extracorporeal shockwave lithotripsy for ureteral stones, as well as the use of ureteral stents for the treatment of trigonal obstructive transitional cell carcinoma, ureterolithiasis, and ureteral strictures. Traditional surgical interventions, like ureterotomy, ureteronephrectomy, and ureteral reimplantation is more vastly reported and accepted. This review will focus on new clinical data using interventional endourological techniques for ureteral obstructions. Conclusions – Various treatment options for ureteral obstructions are now available for veterinary patients, and the trend away from traditional surgical techniques will hopefully be followed now that they are technically and clinically available for dogs and cats. 相似文献
85.
2岁公猫,尿道堵塞排不出尿,造成膀胱及双侧输尿管破裂、尿腹。手术将右肾切除,左侧输尿管与膀胱吻合,同时做尿道造口,输液调节体液平衡、酸碱平衡、离子平衡、控制感染而治愈。目前完全正常,恢复良好。 相似文献
86.
A 12‐year‐old spayed female standard Poodle was presented for investigation of severe hematuria. Abdominal ultrasound and thoracic and abdominal computed tomography identified severe hydronephrosis due to an obstructive ureteral mass with no evidence of metastasis. Histological examination after nephrectomy and ureterectomy confirmed an obstructive ureteral hemangiosarcoma. Forty days after surgery, the dog was presented with severe dyspnea. Survey radiographs of the thorax revealed a severe diffuse nodular interstitial pattern. Postmortem histological examination revealed pulmonary metastasis of hemangiosarcoma. 相似文献
87.
88.
Horizontal starch-gel electrophoresis was used to study crude enzyme extraction from young leaves of 234 clones of Populus tomentosa Cart. selected from nine provenances in North China. Ten enzyme systems were resolved. One hundred and fifty-six clones showing unusual allozyme band patterns at locus Mdh-Ⅰ were found. Three allozyme bands at locus Mdh-Ⅰ were 9:6:1 in concentration. Further studies on the electrophoretic patterns of ground mixed pollen extraction of 30 male clones selected at random from the 156 clones were conducted and it was found that allozyme bands at locus Mdh-Ⅰ were composed of two dark-stained bands and a weak band. Only one group of the malate dehydrogenase (MDH) zymogram composed of two bands was obtained from the electrophoretic segregation of pollen leachate of the same clones. A comparison of the electrophoretic patterns one another suggested that the locus Mdh-Ⅰ coding malate dehydrogenase in diploid species of P. tomentosa was duplicated. The duplicate gene locus possessed three same alleles and was located in mitochondria. The locus duplication of alleles coding malate dehydrogenase in P.tomentosa was discovered and reported for the first time. 相似文献
89.
高等植物基因组中,大部分序列为非表达序列,基因序列所占的比例很小,了解基因在基因组中的分布是研究基因组结构的一个重要方面。在美国能源部资助下,一个毛果杨无性系的基因组测序已经完成并对公众发布。杨树全基因组序列的完成,为我们了解林木基因组中基因的分布提供了一个特例。在本文中,我们利用泊松分析对杨树基因组中基因在各个染色体上的密度进行了检测,结果表明杨树基因组中各条染色体的基因含量存在显著差异。杨树全基因组测序项目揭示现代杨树基因组起源于一次古全基因组复制事件(称为杨柳科基因组复制),所以杨树基因组不同染色体间存在很大的同源复制片段。但是我们的研究显示,杨树基因组中大多数高度同源的染色体上基因的密度与染色体间的同源性没有明显关系,这说明杨柳科全基因组复制事件后,各个高度同源染色体上的基因发生了流失,且基因流失的速率是不一样的。同时本文还对近九万条毛果杨EST序列进行了比对分析,结果显示这些EST序列覆盖的基因仅占杨树基因组中基因总数的16.8%左右。EST测序虽然是发现基因的一个重要手段,但小规模EST测序对基因的覆盖度很低,所以小规模EST测序的应用价值是有限的。 相似文献
90.
JIN Wen-cheng JIN Jian PIAO Shang-guo LI Hui-ying JIANG Yu-ji XUAN Mei-ying ZHENG Hai-lan JIN Ji-zhe JIN Ying-shun LI Can 《园艺学报》2000,36(9):1616-1624
AIM To assess the beneficial effects of pancreatic kininogenase (PK) on renal fibrosis in rat model of unilateral ureteral obstruction (UUO). METHODS Male Sprague-Dawley rats were randomly assigned to 5 groups and treated daily with PK for 7 d and 14 d. Masson trichrome and HE staining were used to assess the degree of tubulointerstitial fibrosis, and immunohistochemistry and Western blot were employed to evaluate the expression of profibrotic and proinflammatory cytokines, and apoptosis- and autophagy-related proteins. RESULTS PK treatment significantly decreased expression of profibrotic and proinflammatory cytokines, and these were paralleled with attenuation of tubulointerstitial inflammation [monocyte chemoattractant protein-1 (MCP-1) and Toll-like receptor 2 (TLR-2)] and fibrosis [transforming growth factor β1 (TGF-β1) and connective tissue growth factor (CTGF)] in a time-dependent manner. Oxidative stress induced by UUO manifested by augment of oxidant enzymes [NADPH oxidase-2 (NOX-2) and NOX-4] and decrease in antioxidant enzymes [superoxide dismutase 1 (SOD1) and SOD2], which was closely associated with dysregulation of apoptosis- and autophagy-related proteins subsequent excessive apoptotic (Bcl-2/Bax and cleaved caspase-3) and autophagy (LC3B, beclin-1 and P62), and all of these were eliminated by administration of PK. CONCLUSION PK treatment protects against the progression of renal fibrosis in obstructed kidneys probably by interfering oxidative stress and programmed cell death. 相似文献