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排序方式: 共有1313条查询结果,搜索用时 15 毫秒
1.
A ten-year-old female poodle was presented for left hindlimb lameness. Radiographically, irregular intramedullary densities of long bones (bone infarcts) and a lytic lesion in the left distal femur were detected. Two years after the first examination, the lesions in the distal femur were definitely identified as osteosarcoma and the dog was euthanized. Pathological and histological changes of the bone infarcts as well as of the osteosarcoma are described. Regarding bibliographical data, occurrence and aetiopathogenesis of osteosarcoma associated with multifocal bone infarction in man and dog are discussed. 相似文献
2.
In order to investigate usefulness of electrodiagnostic methods in Cauda Equina-Compression, 26 dogs with this disease were subjected to electromyography and spinal evoked potentials. 16 normal dogs served as controls. It was found that--after stimulation of the Nn.tibialis, peronaeus, pudendus and coccygeales and recording at the lumbosacral junction--latencies and nerve-conduction velocities were largely normal. However the amplitudes were decreased and--depending on the severity of the compression--the morphology of the potentials was altered although considerable standard deviations were obtained. Electromyographically, increased spontaneous activity with fibrillations and positive sharp waves were found in the myotomes of the lumbosacral nerves. Their number increased according to the severity of the cauda equina compression and they had a centrifugal distribution pattern. Based on these results it appears indicated to perform an electromyographic exam before applying myelography. The technique of spinal evoked potentials will need more refinement and standardisation before being useful in a clinical situation. 相似文献
3.
<正>饲料生产中添加油脂是为了满足生产高浓度能量饲料的要求,同时还可减少氨基酸氧化,提高氨基酸的消化率;抑制葡萄糖和其它前体物质转化为脂肪;促进脂溶性维生素A、D、E、K和某些激素的吸收 相似文献
4.
Steven G. Hall James Finney R. Paul Lang Terrence R. Tiersch 《Aquacultural Engineering》2002,26(4):277-289
A control system was designed to raise and maintain water temperatures within 0.03-ha earthen ponds to a range conducive for spawning (24–30 °C) channel catfish Ictalurus punctatus. Heating was done during February 2001 to April 2001, when temperatures would have otherwise prohibited spawning (<24 °C). Temperature was increased from 10 °C (ambient) by 2 °C per day, and maintained at 27 °C, by the addition of geothermally warmed water (36 °C). The control system substantially increased the controllability and precision of heating ponds compared to manual operation. Systems were designed to control sets of four ponds. In designing this control system, consideration of biological constraints was essential. Reproduction in channel catfish is most strongly influenced by temperature. Because cold fronts are common during the winter and early spring (January–March), it was essential to ensure that pond temperatures did not fall below the range for spawning. Constraints on the heating rate and temperature variability to maintain fish health and stimulate spawning behavior were considered. Components of the control system included temperature measurement devices (type-T thermocouples), a central electronic control unit, electronic switches and electrically actuated ball valves. In response to the temperature sensed by each thermocouple, the controller sent a message to close or open the valve. When the valve was opened, warm water was added to the pond to increase the average pond temperature. Hardware and algorithm design and initial system testing were the major components of this project. The final design incorporated information on relevant biological parameters and safety features including peak pond temperature, independent aeration and water pressure control mechanisms. Initial results indicate successful control of this biological system, and ongoing studies suggest similar mechanisms may be used for additional control objectives. In particular, this system could be used to vary pond temperatures to study biological responses and to cool ponds by addition of well water during summer months. 相似文献
5.
农业高校产学研合作创新的实践与对策建议 总被引:5,自引:3,他引:2
创新是一个民族进步的灵魂,是一个国家和地区兴旺发达的不竭动力。长期以来,农业高校积极利用自身人才与科技优势,主动面向经济建设,把学校优秀的科技成果、充分的人力资源、企业良好的市场运作、雄厚的资金结合起来,开展多种形式的产学研合作创新,推动了农业科技成果向现实生产力的转化,产生了积极的社会效益和经济效益。文章探讨了南京农业大学产学研合作创新的具体实践模式,提出了促进产学研有机结合,加快农业科技创新步伐的对策建议。 相似文献
6.
番茄新品种长丰88是以CT15为母本,CT101-3为父本配制的抗TY、抗线虫杂交一代良种,属无限生长红果类型。生长势强,第7片叶着生第1花穗,每隔2片叶着生一花穗,中早熟。坐果率高、连续结果能力强,春季每穗平均结果 20个,产量59 850 kg/hm~2;果实圆形,无绿色果肩,表面光滑,外形美观。果实硬度大,耐贮运,货架寿命长,单果质量20 g左右,大小均匀。可溶性固形物含量8.9%,VC含量32.43 mg/100 g,总糖3.44%,总酸0.236%。抗病性强,抗番茄黄化曲叶病毒病,根结线虫病发病率为0,灰霉病和早疫病均未见发生。 相似文献
7.
8.
本文用水培方法研究了沙棘短茎段插穗生根的机理。结果表明,在用外源激素处理、控温控湿条件下,沙棘可以用极短的茎段(1~3芽段)插穗产生不定根,进而形成新的植物。沙棘插穗不定根形成有两种方式:一是茎段切面先产生愈伤组织,然后再分化为不定根;二是直接由茎皮层内分生组织产生不定根;且不定根产生具"茎多部位生根效应"。沙棘插穗不定根形成属于"温度敏感型",最适温度为16℃~26℃。外源激素对沙棘短茎段插穗生根表现出良好的诱导效应,而且对插穗苗的生长发育一定的影响,ABT优于GGR;"壮根素"效果优于生根粉,不仅促进发根,而且促进成熟不定根的早期结瘤。 相似文献
9.
Tiphaine Dubos Matias Pasquali Friederike Pogoda Lucien Hoffmann Marco Beyer 《European journal of plant pathology / European Foundation for Plant Pathology》2011,130(2):239-248
A collection of 55 Fusarium graminearum (Gibberella zeae) strains isolated between 1969 and 2009 in Belgium, Canada, Germany, Italy, Luxembourg, or the USA belonging to the three
known chemotypes (3-acetylated deoxynivalenol, 15-acetylated deoxynivalenol and nivalenol) were screened for their sensitivity
towards the fungicide trifloxystrobin using a liquid culture assay. None of the isolates was completely inhibited by trifloxystrobin
concentrations up to 3 mM. For comparison, prothioconazole completely inhibited fungal growth of a standard isolate at concentrations
as low as 0.007 mM. The maximum level of inhibition, which could be obtained by trifloxystrobin, ranged from 14 to 65% among
the strains tested and was not significantly affected by the country of origin or by the chemotype. The absence of significant
differences in resistance levels between the countries of origin and chemotypes as well as the fact that strains isolated
before the market introduction of strobilurins in 1996 also showed a high level of resistance is evidence that this is largely
a case of natural resistance and not primarily related to strobilurin use in agriculture. 相似文献
10.
植物体细胞胚发生与内源激素的关系研究进展 总被引:13,自引:2,他引:13
概述了不同外植体和体胚发生特定部位的内源激素水平、胚性和非胚性愈伤组织的内源激素差异、体胚发生过程中内源激素的变化、内源激素间的平衡等与体胚发生能力的关系以及多胺在植物体胚发生中的作用,并对目前研究中存在的问题进行了讨论。 相似文献