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2.
A 20-year-old pony mare with persistent ventricular tachycardia (VT) was examined cardiopathologically. At necropsy, the heart was enlarged and rounded with both ventricular dilatation. In a longitudinal section of the ventricular septum, a large grayish white patchy lesion (5 x 25 mm) was detected in the relatively higher portion. Microscopically, the lesion was extensive myocardial fibrosis located in the vicinity of the proximal part of the left bundle branch. Partially the fibrotic lesion was in contact with the branch. Such a lesion might play an important role in creating a suitable background for the development of VT via automaticity or reentry mechanism.  相似文献   
3.
ABSTRACT: To clarify the quantitative changes in the transport of orally intubated protein into the blood circulation as macromolecules in development, immunoglobulin Y (IgY) extracted from chicken eggs was administered orally to juvenile Japanese eel, Anguilla japonica . For the first experiment, which was performed before the commencement of artificial feeding, the oral delivery of 2.0 μg/0.1 g bodyweight of IgY resulted in a rapid increase in plasma IgY to a maximum of 2.30 μg/mL. However, the transport of IgY into the blood decreased significantly in the experiments that followed, which were performed after 12, 25 and 42 days. During this period, bodyweight increased approximately by a factor of eight, and rapid growth of the stomach was observed histologically. Possible contributions for the development of the alimentary canal to the diminishment of intestinal protein assimilation are discussed.  相似文献   
4.
Kano  R.  Kubota  A.  Nakamura  Y.  Watanabe  S.  Hasegawa  A. 《Veterinary research communications》2001,25(8):615-622
Using cDNA from a CRFK cell line as a template, PCR amplification was performed with the Ub1S and poly(dT) primers to isolate feline ubiquitin genes. Sequencing of the 495 bp PCR fragment revealed that the putative amino acids induced by this fragment gave a fusion protein consisting of a ubiquitin polypeptide (76 amino acids) and an extension protein of ribosomal proteins L40 (52 amino acids). The putative amino acid sequence of ubiquitin was identical to those of humans, rats and pigs.The recombinant glutathione S-transferase (GST)–feline ubiquitin fusion proteins were produced in Escherichia coli and purified. The fusion proteins had a molecular weight of about 42 kDa and were detected by immunoblot assay with rabbit anti-ubiquitin antiserum.The mRNAs from heat-shocked and non-heat-shocked cells were subjected to RT-PCR (Ub1S and poly(dT) primers) analysis. The molecular weights of the ubiquitinated proteins in heat-shocked CFRK cells were between 18 kDa and 24 kDa by immunoblot assay.These results suggested that there were more ubiquinated proteins in the heat-shocked CRFK cells than in the pre-heat-shocked cells.  相似文献   
5.
It was recently reported that canine parvoviruses (CPV) had entered cat populations and induced disease in infected cats, while they had affected only dogs in the past. It is important to determine whether conventional feline panleukopenia virus (FPLV) vaccines protect against recent CPV infections. In this study, the cross-reactivity of virus-neutralising (VN) and haemagglutinin-inhibition (HI) antibodies in cats induced by FPLV and CPV s were examined. Lower cross-reactivities of VN and HI antibodies against each CPV strain were observed in cats experimentally inoculated with FPLV or vaccinated with an inactivated FPLV vaccine. In addition, we revealed the existence of a novel type of FPLV, which reacted weakly with antibodies induced by the conventional FPLV vaccine.  相似文献   
6.
ABSTRACT: Chub mackerel (34–35 cm, approximately 500 g), which were caught by fishing with a rod and line at the Bungo Channel, Oita prefecture, were rested overnight in a fish preserve and either killed by decapitation (control group) or allowed to struggle in air for 30 min (struggled group). Muscle samples were excised every 4 h, and measurements on breaking strength and histological observations were done for both groups. The breaking strength of muscle in the control group was significantly higher than that in the struggled group, whereby a decrease in breaking strength was delayed for 12 h compared to the struggled group. Light microscopy showed space extension among muscle cells in association with a decrease in breaking strength. Especially in the struggled group, the extended area was larger and the difference in area was significant at the time when breaking strength showed a significant difference. Using electron microscopy, the extended area showed cut and/or disappeared collagen fibrils. From these results, it was demonstrated that struggling to death promoted the degradation of collagen fibrils and the weakening of connective tissue and, resultantly, led to the faster softening of muscle of chub mackerel.  相似文献   
7.
The complete nucleotide sequence was determined for genomic RNA of White clover mosaic virus (WClMV-RC) isolated from red clover (Trifolium pratense) in Japan, It is 5843 nucleotides in length, excluding the poly(A) tail at the 3' terminus. Similar to other potexviruses, it contains five open reading frames (ORFs 1 through 5), which putatively encode an RNA-dependent RNA polymerase (RdRp) (147 kDa), a triple gene block (TGB) (26 kDa/13 kDa/7 kDa), and a coat protein (CP) (22 kDa), respectively. The deduced amino acid sequence of the WClMV-RC CP was identical to that of WClMV-O, one of two New Zealand isolates, but only 85% identical to that of WClMV-M, the other New Zealand isolate, because of heterogeneity in the C-termini of CP amino acid sequences. The implication of this CP heterogeneity is discussed. Received 30 August 2001/ Accepted in revised form 11 January 2002  相似文献   
8.
AIM: To study the molecular biological mechanism and signal transduction pathway of interleukin-1β (IL-1β)-induced apoptosis in A375-S2 melanoma cells. METHODS: Photomicrocropy showed typical apoptotic changes. The cytotoxic effect of IL-1β in vitro and influences of caspases in this effect were measured by MTT assay. The cytotoxicity of cells was assessed by LDH-based assay. Degradation of DNA was detected by agarose gel electrophoresis. RESULTS: The inhibitory effect of IL-1β on A375-S2 cell growth was in a dose and time-dependent manner, and cell death rate reached more than 90% at 72 h after treatment with 10-9mol/L IL-1β. The inhibitors of caspase-family, -1, -3, -8, -9, and -10, partially blocked cell death at early stage. LDH assay showed that major IL-1β-induced cell death was apoptosis, and in a dose and time-dependent manner. Typical apoptotic DNA ladder was observed in agarose gel electrophoresis. CONCLUSION: IL-1β induced apoptosis in melanoma A375-S2 cells by activating caspase pathway.  相似文献   
9.
利用Terra/MODIS数据提取冬小麦面积及精度分析   总被引:7,自引:4,他引:3  
利用遥感技术提取作物播种面积是农情监测研究中一种实用而可行的方法。以河北省藁城市为研究区域,研究利用多时相Terra/MODIS数据提取2004年冬小麦播种面积的技术方法。在分析MODIS波谱特性与冬小麦生物学特征,并考虑了有关植被指数图像对面积提取精度的影响基础上,选择将MODIS数据的Red、Blue、NIR和ESWIR波段作为基础工作波段。利用4种方法提取了2004年藁城市各乡镇的冬小麦播种面积,并利用2004年各乡镇统计数据及土地利用数据进行了精度评价。结果表明:4种方法提取的冬小麦播种面积总体上都与参考值比较吻合,总体误差和平均误差均小于5%。可见,利用Terra/MODIS数据提取冬小麦播种面积是完全可行的。研究还发现,最佳的MODIS数据是冬小麦抽穗期的Red、Blue、NIR、ESWIR波段图像和冬小麦播种期与抽穗期EVI差值图像的组合。  相似文献   
10.
We evaluated the completeness of bony fusion of the atlantoaxial joint (AAJ) through polymethylmethacrylate fixation (PMF) and atlantoaxial plate fixation (APF) using six canine models with dens partial resection. In both groups, the hydroxyapatite content at the AAJ was measured up to 7 months postoperatively using quantitative computed tomography. Histological assessment revealed fibrous fusion in the PMF group. Meanwhile, in the APF group, only one dog achieved fibrous fusion, whereas the remaining three showed bony fusion. To our knowledge, this study was the first to evaluate AAJ fusion histologically after PMF and APF. The present study demonstrates that PMF and APF may stabilize the AAJ without clinical complications. Therefore, PMF and APF are clinically useful fixation methods for atlantoaxial instability.  相似文献   
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