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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.
Hao Wenkang Lang Kuijian Zhang Yanli Li Longchang Weng Guoqing Huang Mingquan Wang Xiangguo 《林业研究》1993,4(2):33-42
Site quality of larch (Larix gmelinii Rupr.) in Da Xingan Mountain in Inner Mongolia was studied systematically with about 1000 temporary plots and computer software.
The nature of site class and site index curve was discussed in view of general mathematical model of height growth. The height
growth of dominant tree of four divisions of forest stands were studied and site index tables were constructed respectively.
In order to unify the comparing standard and convenience for management in this region, site index table was constucted too.
Based on discussing the action and accuracy of forest type, a series of site quality evaluation (forest type-site index class-site
index) was suggested.
This subject of study is supported by the National Natural Scientific Fund (No. 39270549). 相似文献
4.
非公有制林业主体融资问题的思考 总被引:4,自引:0,他引:4
针对不同层次的个体林业,设计了民间融资、"报账制"式银行信贷等方式以求解决个体林农融资困难问题. 相似文献
5.
6.
基于SDAE-BP的联合收割机作业故障监测 总被引:1,自引:0,他引:1
为了解决联合收割机作业故障的非线性特征信号难以提取的问题,该研究提出了一种基于堆叠去噪自动编码器(Stack Denoising Auto Encoder, SDAE)和BP神经网络(Back Propagation,BP)融合的联合收割机作业故障监测及诊断的方法(SDAE-BP)。以转速传感器采集联合收割机脱粒滚筒转速、籽粒搅龙转速、喂入搅龙转速、杂余搅龙转速、风机转速、输送链耙转速、割刀频率以及逐稿器振动频率,并将采集的数据集作为系统的输入。利用SDAE提取输入信号的深层次特征,并由BP神经网络辨识收割机作业状态,实现联合收割机故障监测。在SDAE-BP模型训练过程中,去噪自动编码器(Denoising Auto Encode, DAE)依次经带有不同分布中心噪声的原始数据进行训练,然后将其堆叠,并通过误差反向传播算法对模型参数进行优化,以提升模型识别故障性能和泛化能力。试验结果表明,对于2018年联合收割机田间试验数据,模型的故障诊断准确率达到99.00%,与SDAE和BP神经网络相比,分别提高了1.5和4.5个百分点。将SDAE-BP故障诊断模型用2019年的试验数据进行更新,并用2018年和2019年试验数据进行测试,结果表明,更新后的模型对2018年试验数据的故障识别准确率为99.25%,对2019年试验数据的故障识别准确率为98.74%,更新后模型在2019试验数据集上的故障识别准确率较未更新模型提高了6.52个百分点。该文所建模型能够准确识别联合收割机的故障类型,且具有较好的鲁棒性,对旋转型机械故障监测及预警具有参考价值。 相似文献
7.
Previous studies showed that the yellow seed color gene of a yellow mustard was located on the A09 chromosome. In this study, the sequences of the molecular markers linked to the yellow seed color gene were analyzed, the gene was primarily mapped to an interval of 23.304 to 29.402M. Twenty genes and eight markers’ sequences in this region were selected to design the IP and SCAR primers. These primers were used to screen a BC8S1 population consisting of 1256 individuals. As a result, five IP and five SCAR markers were successfully developed. IP4 and Y1 were located on either side of the yellow seed color gene at a distance of 0.1 and 0.3 cM, respectively. IP1, IP2 and IP3 derived from Bra036827, Bra036828, Bra036829 separately, co-segregated with the target gene. BLAST analysis indicated that the sequences of newly developed markers showed good collinearity with those of the A09 chromosome, and that the target gene might exist between 27.079 and 27.616M. In light of annotations of the genes in this region, only Bra036828 is associated with flavonoid biosynthesis. This gene has high similarity with the TRANSPARENT TESTA6 gene, Bra036828 was hence identified as being the gene possibly responsible for yellow seed color, in our research. 相似文献
8.
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
9.
10.
Santana Pedro Henrique Lopes Burak Diego Lang Thiengo Cássio Carlette Peçanha Anderson Lopes Neves Mirna Aparecida Mendonça Eduardo de Sá 《Journal of Soils and Sediments》2020,20(11):4103-4110
Journal of Soils and Sediments - After the greatest environmental disaster in the history of Brazil and the deposition of the iron ore tailings in alluvial regions, the process of revegetation for... 相似文献