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为探讨水温对不同规格细鳞鲑(Brachymystax lenok)摄食和生长的影响,采用自制饲料在不同温度(6℃、10℃、14℃、18℃和22℃)下对小(7 g)、中(68 g)、大(169 g)三种规格的细鳞鲑进行饲养实验。研究结果表明,小规格细鳞鲑在18℃时获得最大摄食率,中规格细鳞鲑在14℃和18℃获得最大摄食率,而大规格细鳞鲑在14℃时获得最大摄食率(P0.05)。小、中规格细鳞鲑在14℃和18℃时的特定生长率最高,而大规格细鳞鲑特定生长率在14℃时有最大值(P0.05)。相同水温条件下,细鳞鲑的最大摄食率随体重的增加而增加,特定生长率随体重的增加而降低,鱼体能值随体重的增加而升高。多元回归分析显示,水温和体重对细鳞鲑最大摄食率(C_(max))的影响可以用下式模拟:lnC_(max)=–6.8282+1.1603ln W+0.3729T–0.0095T~2–0.0157Tln W;水温和体重对细鳞鲑湿重特定生长率(SGR_w,%/d)的影响可用下式拟合:ln SGRw=–1.9390–0.2184ln W+0.4376T–0.0147T~2,水温和体重对细鳞鲑能值E_t(k J/fish)的影响可用如下方程进行较好拟合:ln Et=1.0012+1.2070ln W–0.0002T~2–0.0021Tln W。逐步回归分析表明,水温和体重对细鳞鲑最大摄食率和鱼体能值的影响存在显著的交互作用(P0.05),而对湿重特定生长率的影响不存在交互作用(P0.05)。综合上述研究结果可以认为细鳞鲑养殖的适宜水温范围是14~18℃。 相似文献
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为探究黑素皮质素受体1基因(MC1R)在橘色双冠丽鱼胚胎发育和体色形成过程中的表达定位及功能,本研究首先制备了MC1R基因的RNA正反义探针,T7方向转录的正义RNA探针质量浓度为447.529 ng/μL,SP6方向转录的反义RNA探针质量浓度为342.698 ng/μL。经10～20倍稀释后的探针用于原位杂交,MC1R基因探针表达定位显示,随橘色双冠丽鱼胚胎的发育杂交信号总体呈逐渐减弱趋势,原肠期和视泡期其卵黄和胚体侧卧部分有杂交信号分布;出膜期其脊柱、卵黄囊及其内容物和色素细胞内出现杂交信号;出膜期第1天,卵黄表面有信号分布。总体来看,杂交信号在脊索、卵黄囊、卵黄囊内容物质及色素细胞有特异表达,而以正义探针作为阴性对照组在5个胚胎阶段均无任何信号,杂交信号显现的MC1R表达定位说明其在橘色双冠丽鱼色素细胞的分化、迁移中起到重要调控作用,也与神经、营养、免疫功能相关,初步建立了鱼类体色相关基因功能和定位研究的整胚原位杂交方法。 相似文献
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AIM: To investigate the effects of transforming growth factor β1 (TGF-β1) on murine-derived dendritic cells (DC). METHODS: Murine bone marrow cells were cultured with GM-CSF and TGF-β1 to develop TGF β-DC. Then they were stimulated by lipopolysaccharide (LPS). Their phenotypes were assessed by flow cytometry (FCM). The allogeneic stimulating capacity of DC was measured by mixed lymphocyte reaction (MLR) using BrdU ELISA method. IL-12 p70 protein was detected by ELISA and the expressions of Toll like receptor 4 (TLR4) on DCs were measured by semi-quantitative RT-PCR and FCM. RESULTS: Compared to immature DC (imDC) cultured with GM-CSF alone, the expressions of CD80, CD86, I-Ab and CD40 in TGF β-DC were lower. The TGF β-DC was resistant to maturation by LPS. Maturation resistance was evident from a failure to up-regulate CMs, to stimulate larger T cell proliferation and to increase secretion of IL-12 p70. Down-regulation of TLR4 expression on TGF β-DC was also found. CONCLUSION: TGF-β1 inhibits the expression of co-stimulatory molecules on DC. It is resistant to maturation stimulus (LPS) and might be linked with TLR4 down-regulation. 相似文献
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AIM: To analyze and identify the phosphoproteins associated with diazoxide preconditioning. METHODS: Proteomics technique was used to investigate the changes of phosphoprotein after diazoxide preconditioning. Adult rat ventricular myocytes were pretreated in the presence and absence of 200 μmol/L diazoxide for 10 min. Phosphoproteins prepared and enriched respectively from control and diazoxide pretreated groups were then separated by two-dimensional (2D) gel electrophoresis and stained with sliver staining kit. Phosphoproteins of interest were further identified by mass spectrometry. RESULTS: Associated with diazoxide preconditioning, the proteins of chaperonin containing TCP-1 and hypothetical protein XP_346548 were phosphorylated significantly. The proteins of 94 kD glucose-regulated protein, calpactin I heavy chain and ferritin were dephosphorylated markedly (P<0.05). CONCLUSION: These findings suggest that cardiomyocytes undergo significant posttranslational modification via phosphorylation in a multitude of proteins in response to diazoxide preconditioned signaling, which may mediate myocardioprotection signaling downstream mitochondrial staining dish KATP channel induced by ischemic preconditioning. 相似文献
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MOU Bo YANG Zhi-hong ZHAO Jia-wei WANG Xuan-chun DONG Xue-hong LIU Yu HU Ren-ming 《园艺学报》2007,23(5):888-892
AIM: To verify and localize the expression of nicotinamide N-methyltransferase (NNMT) in pancreas of streptozotocin(STZ)-induced diabetic monkeys and understand its important role in β-cell destruction in the pathogenesis of diabetes. METHODS: Through an olig-microarray gene chip, NNMT was identified as the most obviously up-regulated genes in pancreas of STZ-induced diabetic monkeys versus controls. Semiquantitative RT-PCR and Western blotting were performed to verify the differential expression at mRNA and protein level respectively. Then the cellular localization of NNMT expression within pancreas was identified by immunohistochemical(IHC) staining.RESULTS: An obvious high expression of NNMT at both mRNA and protein levels was shown in pancreas of STZ-induced diabetic monkeys compared to that of controls. Further localization of the protein by IHC staining in pancreas specimens showed that its altered expression was restricted to central islets, most of which were β cells.CONCLUSION: Expression of NNMT is increased in islets of STZ- induced diabetic monkeys, which infers that NNMT might participate in the process of β cell damage in diabetes probably through the mechanism of energy metabolism disturbance. 相似文献
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为了研究猪囊尾蚴乳酸脱氢酶(LDH)的表达,试验选择四川省雅江县呷拉乡猪带绦虫病患者,给其口服槟榔-南瓜子驱虫,收集、制备虫卵悬液(8万个/mL),再给3头20日龄三元杂交乳猪猪灌胃虫卵悬液,每头1 mL,40 d后收集、制备猪囊尾蚴蛋白,进行双向电泳(2-DE)分析,将凝胶蛋白斑点转移至聚偏氟乙烯膜(PVDF膜),用自制的大鼠抗猪带绦虫LDH血清作为一抗、健康大鼠血清作为阴性对照进行蛋白质印迹(Western-blotting)分析。结果表明:双向电泳凝胶共检测到(207±9)个蛋白质斑点,相对分子质量(Mr)为14 400～94 000,等电点(pI)为3.0～10.0;试验组特异性抗原抗体阳性杂交斑点为1个,阴性对照未见阳性杂交斑点;将Western-blotting检测的抗原抗体阳性杂交斑点与原双向电泳凝胶斑点进行比对,找到对应蛋白斑点,经ImageMaster 2D Platinum 5.0软件分析后初步确定该蛋白斑点的pI/Mr为7.03/35 368,与猪带绦虫LDH的pI/Mr理论推导值接近,说明猪囊尾蚴表达LDH。 相似文献
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