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101.
Five isonitrogenous and isoenergetic diets with soybean oil (SO), linseed oil (LO), algae oil from Schizochytrium sp. (AO), mixed oil (MO, SO:LO:AO = 1:1:1) and fish oil (FO; control group) were selected to feed juvenile Onychostoma macrolepis (initial weight 1.86 ± 0.07 g) for eight weeks. The results showed that in the LO and FO groups fish grew best. There was no significant difference in specific growth rate (SGR) and feed efficiency (FE) between the MO and FO groups (p > .05). The highest contents of 18:2n‐6, 18:3n‐3 and 22:6n‐3 in liver and muscle were found with the SO, LO and AO groups, respectively (p < .05). There appeared the highest malondialdehyde (MDA) content and the lowest superoxide dismutase (SOD) activity in the fish liver of the AO group. There appeared the highest concentrations of serum glucose (GLU), cholesterol (CHOL) and triglycerides (TG) in the SO group. The expressions of lipid anabolism genes were significantly up‐regulated by dietary SO and LO (p < .05). The expressions of lipid catabolism genes were significantly higher with the AO, MO and FO groups (p < .05). This study recommended that LO or MO as a better vegetable oil source for juvenile O. macrolepis.  相似文献   
102.
AIM:To investigate the effect of 17β-estradiol (E2) on myocardial hypertrophy induced by endothelin-1(ET-1) and the related mechanism. METHODS:Myocardial cells from neonate rats were cultured in vitro and myocardial hypertrophy model was established with ET-1.The effects of 17β-estradiol on myocardial hypertrophy were observed. The role of ERK1/2 in the effects of 17β-estradiol was also detected. RESULTS:Compared with control group,ET-1 increased cell protein content,cell surface area and [3H]-Leucine [3H]-Leu) incorporation. Pretreatment with E2 for 24 h could inhibit the increase in cell protein content,cell surface area and [3H]-Leu incorporation induced by ET-1.ET-1 significantly stimulated ERK1/2 activity,which was prevented by pretreatment with E2.Tamoxifen,estradiol receptor antagonist,partially inhibited the effect of E2. The ability of ET-1 to stimulate [3H]-Leu incorporation was significantly blocked by PD98059,which could enhance the inhibitory effect of E2 on the increase of [3H]-Leu incorporation in cardiomyocytes induced by ET-1.CONCLUSION:E2 can inhibit cardiomyocyte hypertrophy induced by ET-1. This effect is mediated by estrogen receptor. ERK1/2 signal pathway is closely correlated with the inhibitory effect of E2 on cardiomyocyte hypertrophy induced by ET-1.  相似文献   
103.
刘亮  王丹  王诚  陈红  胡国宇  黎青 《核农学报》2021,35(5):1009-1019
为研究60Co-γ射线对栀子插条的辐射诱变作用及3种保护剂的保护效应,采用不同辐射剂量(5、10、20、40 Gy)辐射栀子插条,运用氯化钠(NaCl)、半胱氨酸(Cys)及维生素C(Vc)3种保护剂,分别设置4种不同浓度浸泡辐射后插条,分析不同辐射剂量及保护剂处理栀子插条的生根率、存活率、根长、根数、成株率、节间长度、分枝数、叶片数、叶长、叶宽等指标。结果表明,随着辐射剂量的增加,栀子插条的损伤逐渐增大。栀子插条60Co-γ射线半生根剂量为21.22 Gy,半致死剂量为81.65 Gy,半成株剂量为20.30 Gy。3种保护剂在较高剂量辐射下具有显著的保护效应。在20 Gy辐射剂量下,3.00 g·L-1 NaCl处理对栀子插条生根、生长保护效果较好。40 Gy辐射剂量下,0.12 g·L-1 Cys和0.08 g·L-1 Vc处理对栀子插条生根、生长保护效果较好。综上所述,3种保护剂均对较高剂量60Co-γ射线损伤具有较好的保护作用,且保护效果与辐射剂量、保护剂浓度相关。本研究为栀子的辐射诱变育种及保护剂应用提供了技术参考。  相似文献   
104.
以5个杂交中稻组合为材料,在智能人工气候室条件下,研究了极端高温对杂交中稻结实率的影响与肥水调控效果.结果 表明,孕穗期和抽穗期日均温33℃以上对结实率的影响显著,38℃以上时结实率急剧下降,抽穗期遇38℃高温,参试品种的结实率均在10%以下;孕穗期受高温影响明显比抽穗期小,33℃条件下,孕穗期高温产量损失在10%以内...  相似文献   
105.
AIM:To investigate the effects of the juice of fructus hippophae(JFH) on thrombocytopenia in rats.METHODS:Forty-eight wistar rats were divided into control group, model group, Yixuesheng-Jiaonang (YSJN) group and JFH group. Rats were injected intraperitoneally with cyclophosphamide (CTX, 30 mg/kg) or saline once a day for 3 days. And then, Saline, YSJN or JFH was administered (ig) once a day for 11 days. On the second, fouth, sixth and eighth day, the thrombocyte were counted, the mean platelet volume (MPV) and PDW were examined. On the eighth day, the cAMP, cGMP in platelets and platelet aggregation function were also examined.RESULTS:JFH could shorten the time of blood coagulation, increase the count of platelet, and enhance the platelet aggregation function. The experiment also showed that the JFH could decrease cGMP content in platelet.CONCLUSION:JFH could enhance blood coagulation and quality of platelet and prevent thrombocytopenia induced by cyclophosphamide in rats.  相似文献   
106.
用膨化大豆代替豆粕对杂交鲟生长和免疫的影响   总被引:1,自引:0,他引:1  
用膨化大豆分别替代0(G1组)、35%(G2组)、65.8%(G3组)、93.2%(G4组)豆粕,配制成4种等氮等能的饲料,饲喂体重为(75.3±3.8)g的杂交鲟Acipenser schrenckii ♀×Acipenser baeri ♂。6周的试验结果表明:用膨化大豆代替豆粕后,各处理组杂交鲟生长性能差异不显著(P〉0.05);与G1组相比,G3组鱼血浆中SOD和溶菌酶活力分别提高13.6%和59.4%(P〈0.05);G3组和C4组鱼血浆中总蛋白和球蛋白显著增加(P〈0.05),其中总蛋白分别提高9.9%和11.5%,球蛋白分别提高12.0%和14.7%。  相似文献   
107.
A field experiment was conducted to study the effects of combination of straw incorporation and water management on fluxes of CH4, N2O and soil heterotrophic respiration (Rh) in a paddy field in subtropical central China by using a static opaque chamber/gas chromatography method. Four treatments were set up: two rice straw incorporation rates at 0 (S1) and 6 (S2) t ha?1 combined with two water managements of intermittent irrigation (W1, with mid-season drainage) and continuous flooding (W2, without mid-season drainage). The cumulative seasonal CH4 emissions for the treatments of S1W2, S2W1 and S2W2 increased significantly by 1.84, 5.47 and 6.63 times, respectively, while seasonal N2O emissions decreased by 0.67, 0.29 and 1.21 times, respectively, as compared to S1W1 treatment. The significant increase in the cumulative Rh for the treatments S1W1, S2W1 and S2W2 were 0.54, 1.35 and 0.52 times, respectively, in comparison with S1W2. On a seasonal basis, both the CO2-equivalents (CO2e) and yield-scaled CO2e (GHGI) of CH4 and N2O emissions increased with straw incorporation and continuous flooding, following the order: S2W2>S2W1>S1W2>S1W1. Thus, the practices of in season straw incorporation should be discouraged, while mid-season drainage is recommended in paddy rice production from a point view of reducing greenhouse gas emissions.  相似文献   
108.
应用早稻秸秆全量还田和连作晚稻轻简化栽培技术是当前发展新型农作制度和质量效益型农业的重要措施。此研究对早稻秸秆全量还田条件下连作晚稻手移栽、机插和抛秧3种栽培方式进行比较,结果表明,连作晚稻手移栽栽培方式产量最高,机插次之,抛秧的产量最低。但手移栽栽培方式的产量与机插处理的差异不显著,但二者均与抛秧栽培方式的差异达到显著水平。与手移栽处理相比,机插处理抽穗期、成熟期、抽穗至成熟期的干物质含量均相近,且手移栽与机插栽培方式抽穗至成熟期的干物质积累量显著高于抛秧。秸秆还田降低了3种稻作方式的有效分蘖数,抛秧处理的差异最大。此外,与手移栽和抛秧相比,机插栽培方式显著节本省工。综合来看,秸秆全量还田条件下,机插稻表现高产稳产、省工节本,是浙江省双季稻区值得推广的栽培方式,有着广阔的应用前景。  相似文献   
109.
旨在分析母猪的出生年份、出生季节、初生重、开测日龄等固定效应对长白、大白猪主要生长性状的影响,并对目标生长性状进行遗传参数估计(遗传力、遗传方差、表型相关和遗传相关),为猪的遗传改良提供基本依据.本试验利用GLM模型分析试验猪群(398头长白猪和1176头大白猪)的固定效应对猪生长性状的影响,并采用多性状动物模型对目标...  相似文献   
110.
丁红  刘东  李陶 《农业工程》2010,(12):84-88
针对现有的旱情评价方法容易出现评价等级离散和结果不易分辨等问题,提出了基于人工鱼群的投影寻踪旱情评价模型,利用人工鱼群算法优化投影指标函数寻求最佳投影方向,同时采用自适应人工鱼步长和拥挤度因子对人工鱼群算法进行改进,克服其易陷入局部最优等缺点,提高了全局搜索能力和收敛速度。以三江平原红兴隆分局为例,选用降雨距平百分率、Z指标和降水温度均一化指标3个指标综合计算投影值,建立了基于改进人工鱼群算法的三江平原投影寻踪旱情评价模型。结果表明,该模型有效避免了单项指标评价的不相容性,用于区域旱情评价是切实可行的,为旱情评价提供了参考。  相似文献   
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