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1.
Paddy and Water Environment - Leakage of agricultural pipes has been increasingly frequent problems due to corrosion, loosening of joints, and cracks, which result in the subsidence of peripheral...  相似文献   
2.
Ghrelin, a novel 28-amino acid peptide with an n-octanoyl modification at Ser3, has been isolated from rat and human stomach as an endogenous ligand for the growth hormone secretagogue receptor. Here, we purified feline ghrelin and examined its possible physiological role in cats. The major active form of feline ghrelin is a 28-amino acid peptide octanoylated (C8:0) at Ser3; except for one amino acid residue replacement, this structure is identical to those of rat and human ghrelins. However, much structural divergence in peptide length and fatty acid modification was observed in feline ghrelin: peptides consisting of 27 or 26 amino acids lacking Gln14 and/or Arg28 were found, and the third serine residue was modified by octanoic acid (C8:0), decanoic acid (10:0), or unsaturated fatty acids (C8:1, C10:1 and C10:2). In agreement with the structural divergence, two kinds of cDNA with different lengths were isolated. Administration of synthetic rat ghrelin increased plasma growth hormone levels in cats, with a potency similar to that in rat or human. Plasma levels of ghrelin in cats increased approximately 2.5-fold after fasting. The present study indicates the existence of structural divergence in feline ghrelin and suggests that, as in other animals, ghrelin may play important roles in GH release and feeding in cats.  相似文献   
3.
A 6-month-old barrow presented with lethargy, inappetence and dysstasia. At necropsy, multiple coalescing hemorrhagic foci were detected in the margins of the spleen. Gram-positive bacilli were isolated from the spleen, kidney, muscle and liver. Comparative 16S rDNA gene sequencing analysis of the isolates (TO16177) revealed that they would be the same species of unpublished Arcanobacterium species strain HJ57-14E (accession no. gi 18873551) (99.7% similarity based on a comparison of 675 bp). Histologic examination of the splenic tissue sections revealed extensive necrosis and inflammation, and gram-positive bacilli were discernible. Multifocal necrosis was also detected in the liver. Immunohistochemically, the isolates were cross-reacted with polyclonal antibodies against Arcanobacterium pyogenes and Actinomyces naeslundii, and the reaction was strong for the latter. Similar reactions were found in the suppurative lesions of the tonsil, and occasionally in the spleen and lymph nodes. The present results indicate that the unpublished Arcanobacterium species induced multiple organ failure accompanied by acute hemorrhagic necrotizing splenitis in this growing-finishing pig.  相似文献   
4.
One hundred dogs that were positive for canine distemper virus antigen and inclusion bodies in the tonsils were examined for the distribution of inclusion bodies in various tissues. Inclusion bodies were found in the lungs (70 dogs), brains (20 dogs), urinary bladders (73 dogs), stomachs (78 dogs), spleens (77 dogs), and lymph nodes (81 dogs) of the dogs. Based on these results, the tonsils may be the most suitable tissue for detection of inclusion bodies in canine distemper.  相似文献   
5.
Ethylene biosynthesis in kiwifruit, Actinidia chinensis ‘Sanuki Gold’ was characterized using propylene, an ethylene analog, and 1-methylcyclopropene (1-MCP), an inhibitor of ethylene perception. In fruit harvested between a young stage (66 days after pollination) (DAP) and an early commercial harvesting stage (143 DAP), 2 days of exposure to propylene were sufficient to initiate ethylene biosynthesis while in fruit harvested at commercial harvesting stage (154 DAP), 4 days of propylene treatment were required. This observation suggests that response of ethylene biosynthesis to propylene treatment in kiwifruit declined with fruit maturity. Propylene treatment resulted in up-regulated expression of AC-ACO1, AC-ACO2, AC-SAM1 and AC-SAM2, prior to the induction of AC-ACS1 and ethylene production, confirming that AC-ACS1 is the rate limiting step in ethylene biosynthesis in kiwifruit. Treatment of fruit with more than 5 μL L?1 of 1-MCP after the induction of ethylene production subsequently suppressed ethylene production and expression of ethylene biosynthesis genes. Treatment of fruit with 1-MCP at harvest followed with propylene treatment delayed the induction of ethylene production and AC-ACS1 expression for 5 days. These observations suggest that in ripening kiwifruit, ethylene biosynthesis is regulated by positive feedback mechanism and that 1-MCP treatment at harvest effectively delays ethylene production by 5 days.  相似文献   
6.
7.
New strains of Melon necrotic spot virus (MNSV), designated MNSV-YS and MNSV-KS, caused much more severe growth retardation on melon plants than MNSV-NH, which was previously reported as the most severe strain of MNSV in Japan. MNSV-YS spread much more quickly than MNSV-NH in infected plants, and induced more severe growth retardation, even though the appearance of necrotic lesions on inoculated cotyledons was much slower. MNSV-KS had properties intermediate between those of the other two strains. The results suggest that faster-spreading strains can multiply more rapidly as a result of lower levels of activity in inducing necrotic lesions in melon plants. The complete sequences of MNSV-YS and MNSV-KS were determined, and an RT–PCR–RFLP method based on these sequences was successfully developed to detect and discriminate between the three strains.  相似文献   
8.
Sarcocystis sp. was detected from cattle slaughtered in Saitama Prefecture, Japan. The cysts were 3,400-4,400 x 198-238 microm in size and had the thick cyst wall which was 7 to 10 microm thick and provided with finger-like villar protrusions. The protrusions were 8-9.5 x 2-2.5 microm in size and had microtubules in the core.  相似文献   
9.
The cell wall constituents of feces from three faunated and three defaunated (without ruminal ciliate protozoa) cattle fed on a Sudangrass hay and concentrate mixture (8:5) were analyzed. There was little difference in digestibility of dry matter between the faunated and defaunated cattle. Analysis of the fecal sugar residues revealed that the digestibilities of arabinose and galactose, derived from pectic and hemicellulosic substances located within the compound middle lamella, were higher in the defaunated cattle than the faunated cattle (P < 0.05), whereas the digestibilities of glucose and xylose, derived mainly from cellulose and xylan, were unchanged by the removal of protozoa. The digestibility of lignin was not different between the faunated and defaunated cattle, but those of mannose and p‐coumaric acid were lower in the defaunated than in the faunated animals (P < 0.05). The ratio of primary cell wall to secondary cell wall in fecal plant materials was lower for the defaunated than for the faunated cattle. The results in this study suggested that the defaunation enhanced the microbial degradation of the thin cell walls, but depressed the degradation of developed cell walls.  相似文献   
10.
六月龄去势公猪表现昏睡、食欲不振、站立困难。尸检发现脾脏边缘呈多重出血灶。从脾脏、肾脏、肌肉和肝脏中分离出革兰氏阳性杆菌,对分离株(TO16177)的16S rDNA基因序列比较分析发现,其可能与未发表过的隐秘杆菌属HJ57-14E菌株(登记号:gi18873551)(比较675bp个碱基,相似性达99.7%)为同一个属。脾脏组织切片的组织学检查发现呈广泛性坏死和炎症,其中革兰氏阳性杆菌显而易见。肝脏中可见多病灶的坏死斑。免疫组织化学检测发现,分离株与抗化脓性隐秘杆菌属(Arcanobacterium pyogenes)和内氏放线菌(Actinomyces naeslundii)的多克隆抗体具有交叉反应,且与后者的交叉反应更强烈。相似的反应也见于扁桃体的化脓灶中分离株,偶尔也见于脾脏和淋巴结中的分离株。本研究结果表明,这种未公开发布的隐秘杆菌属的细菌会引起生长肥育猪多器官功能衰竭,而后继发急性出血性坏死性脾炎。  相似文献   
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