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191.
本文通过对厦门海水养殖鱼虾病害的病原、流行情况、危害程度等的调查和研究,分析海水养殖鱼虾病害流行的主要特点以及病毒病、细菌病和寄生虫病的发病规律,从病害的检疫防疫,养殖模式,健康抗病苗种的培育,宏观调控和健康养殖,渔药的使用和管理,技术培训等方面提出海水养殖鱼虾病害控制对策。 相似文献
192.
Christopher Beckingham Janet PhillipsMark Gill Andrew J. Crossthwaite 《Pesticide biochemistry and physiology》2013
The peach–potato aphid Myzus persicae is a pest of many commercial crops due to its polyphagous nature of feeding and has a well-documented history of acquiring resistance to insecticides. In 2009 a strain (M. persicae FRC) emerged in southern France with a point mutation (R81T) at the nicotinic acetylcholine receptor (nAChR), the target site for neonicotinoids such as imidacloprid. This point mutation was associated with the loss of the high affinity imidacloprid binding site (pM Kd), with the single remaining binding site (low nM Kd) highly overexpressed compared to laboratory controls (Bass et al., 2011 [1]). Here we report that after 2 years of continuous selection in the glass house environment with neonicotinoids, the total level of IMD-sensitive nAChRs (low nM Kd) in M. persicae FRC is now comparable to laboratory controls (pM and low nM Kd). Interestingly, despite this large reduction in IMD-sensitive nAChRs, this was not associated with any significant alteration in NNIC-lethality. Additionally, sustained absence of neonicotinoid-selection did not alter nAChR protein levels. We suggest that alterations in nAChR protein expression level described in the original characterisation of the field-isolated M. persicae FRC is unlikely to have been a direct consequence of the R81T mutation. Rather, we speculate that nAChR expression in aphids is likely influenced by as yet unknown conditions in the natural field environment that are absent in the laboratory setting. 相似文献
193.
Coz-Rakovac R Strunjak-Perovic I Hacmanjek M Popovic NT Lipej Z Sostaric B 《Veterinary research communications》2005,29(8):677-687
Histological and biochemical procedures were employed to study liver histomorphology and plasma levels of aspartate aminotransferases
(AST), alanine aminotransferase (ALT), triglyceride (TRIG), cholesterol (CHOL), glucose (GLU) and total protein (TP) in cultured
(CSB) and wild sea bass (WSB) (Dicentrarchus labrax) from the northern part of the Adriatic Sea. Histopathological changes in liver included varying degrees of infiltration
and lipid degeneration of hepatocytes in examined cultured fish. No significant differences between median AST values of CSB
(44 IU) and WSB (45 IU) were observed. Values of ALT were <5 IU in both groups. TRIG, CHOL, GLU and TP levels were higher
in CSB (2.08 mmol/L, 3.67 mmol/L, 10.66 mmol/L and 49 g/L, respectively) than in WSB (0.67 mmol/L, 2.74 mmol/L, 3.68 mmol/L
and 36 g/L, respectively). The study showed differences between plasma biochemical parameters and liver histomorphology of
CSB and WSB. This can be explained as a consequence of different diets (artificial in contrast to natural foods), which influence
energy metabolism. 相似文献
194.
Application of a radioimmunoassay for detection of the major internal antigen (p24) of bovine leukemia virus from cultured lymphocytes of cattle 总被引:1,自引:0,他引:1
M J Schmerr M J van der Maaten J M Miller 《Comparative immunology, microbiology and infectious diseases》1980,3(3):327-336
A sensitive and specific radioimmunoassay for the major internal antigen of bovine leukemia virus has been applied to detecting this protein in cultured lymphocytes of infected cattle. The specificity inherent in this assay offers obvious advantages over a previously described syncytium induction assay for infectious bovine leukemia virus, because false positive reactions due to other viruses such as bovine syncytial virus are avoided. Investigations of various culture conditions indicated that maximal amounts of antigen had been produced after incubation for 72 hr at 37°C. Lymphocyte concentrations of 106?5×107 cells/ml gave satisfactory results. Tests of cultured lymphocytes from bovine leukemia virus infected or bovine leukemia virus-free cattle indicated a comparable sensitivity between the radioimmunoassay and syncytium induction assay in the detection of bovine leukemia virus infections. 相似文献
195.
利用半定量RT-PCR法分析比较了甘油三酯水解酶(Triacylglycerol hydrolase,TGH)和激素敏感脂酶(Hormone-sensitive lipase,HSL)基因在不同猪种、不同发育阶段及不同部位脂肪组织中转录表达的差异,探讨其在猪脂肪组织的表达规律。结果显示,脂肪型个体TGHmRNA表达丰度显著低于瘦肉型和杂交型个体,成年猪较初生仔猪低,皮下、腹膜和内脏脂肪组织中TGH表达量依次递增;其变化规律与HSL相同。此外,对分离培养的原代前体脂肪细胞通过诱导分化和油红O染色区分分化状态,分析TGHmRNA表达的时序变化,发现TGH在前脂肪细胞中不转录表达,诱导分化后开始表达,且在诱导分化第4天表达量最高,分化第10天表达量下降,达到峰值的时间较HSL早。结果表明,TGH的表达与个体肥胖程度、年龄、脂肪组织部位以及脂肪细胞分化程度相关,同时,在脂肪细胞分化过程中,TGH表达峰值早于HSL,提示TGH在脂肪细胞发育过程中可能较早承担基础脂解作用。 相似文献
196.
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198.
LI Rong-fu LI Yang-qiu CHEN Shao-hua YANG Li-jian ZHANG Tao ZHONG Jun ZHANG Yu-ping 《园艺学报》2002,18(10):1196-1200
AIM: To investigate clonal expansion and specific cytotoxicity of TCR Vβ subfamily T cells from acute myelogenous leukemia M2a subtype (AML-M2a)patients and normal individuals induced by AML-M2a cells, respectively. METHODS: Complementarity determining region 3(CDR3) of TCR β with variable region genes was amplified in autologous or allogeneic T cells from mixed lymphocyte and tumor culture (MLTC) using RT-PCR. The positive products were further analyzed to identify the clonality of T cells by genescan. The specific cytotoxicity of T cells was analyzed by MTT. RESULTS: T cells from both M2a patients and normal individuals after MLTC showed high response to M2a cells with 4-17 TCR Vβ subfamily dominant utilization, one or two clonal expansion of T cells were identified in some predominant TCR Vβ subfamilies. Difference of distribution and clonal expansion of TCR Vβ subfamily T cells were related to source of T cells and the phase during MLTC. Compared with LAK cell, most of T cells from MLTC were CD3+CD8+T cells with higher and more specific cytoxicity to the induced cells, M2a cells, but not HL60 or K562 cell line. CONCLUSION: Clonal expansion of TCR Vβ subfamily T cells stimulated selectively by M2a cells may be a specific immune response of autologous and allogeneic T cells to M2a cells associated antigen. The T cells induced by M2a cells have the ability of specific cytoxicity to the AML-M2a cells. 相似文献
199.
野生与人工养殖牙鲆亲鱼不同组织脂肪酸的比较 总被引:5,自引:1,他引:5
为研究脂肪酸对牙鲆繁育性能的影响, 采用生物化学方法, 对野生和养殖牙鲆亲鱼肌肉、肝脏及卵中脂肪酸组成分别进行测定。结果表明: (1) 牙鲆肌肉、肝脏和卵中脂肪含量大小关系为肝脏>卵>肌肉。野生亲鱼肌肉和卵中脂肪含量显著低于养殖亲鱼(P<0.05), 肝脏脂肪含量与养殖亲鱼无显著差异; (2) 牙鲆亲鱼3种组织中均检测出21种脂肪酸。野生亲鱼肌肉中饱和脂肪酸(SFA)与养殖亲鱼无显著差异, 单不饱和脂肪酸(MUFA)显著低于养殖亲鱼(P<0.05)。肝脏和卵中SFA显著高于养殖亲鱼(P<0.05), MUFA与养殖亲鱼无显著差异; (3) 野生亲鱼肌肉、肝脏和卵中高不饱和脂肪酸(PUFA)的含量, 尤其是肝脏和卵中C20:5n-3(EPA)、C22:6n-3(DHA)的含量均显著低于养殖亲鱼(P<0.05), 但肌肉和卵中的C20:4n-6(ARA)含量明显高于养殖亲鱼(P<0.05); (4) 野生牙鲆亲鱼肌肉、肝脏和卵中n-3/n-6 PUFA及EPA/ARA显著低于养殖亲鱼(P<0.05), 肝脏中DHA/EPA显著高于养殖亲鱼(P<0.05), 但野生亲鱼肌肉和卵中的DHA/EPA与养殖亲鱼无显著差异。比较结果说明, DHA、EPA和ARA等PUFA是与牙鲆繁殖性能密切相关的重要脂肪酸。在牙鲆亲鱼养殖过程中, 除了提供牙鲆亲鱼足够的脂肪酸营养外, 也应注意各种脂肪酸, 尤其是PUFA中各种脂肪酸之间的添加比例, 从而保证亲鱼的繁殖性能及卵和仔鱼的质量。 相似文献
200.