SO2对葡萄采后呼吸强度及内源激素的影响

采用气相色谱法和改进的高效液相色谱法研究发现：‘无核白’葡萄果粒为非跃变型呼吸类型，其乙烯释放量很低，但释放潜力很高，切伤后乙烯释放速率迅速增高；果梗和穗梗为跃变型呼吸类型，有很高的呼吸高峰和乙烯释放高峰。适量的ＳＯ２保鲜处理对葡萄的呼吸强度、脱落酸（ＡＢＡ）含量及乙烯释放具有明显抑制作用，对生长素（ＩＡＡ）、赤霉素（ＧＡ）有促进作用，既可抑制葡萄生理衰老，又可减轻葡萄的落粒，延长葡萄采后贮藏寿命     

Association of adrenocorticotrophin and cortisol concentrations with peripheral blood leukocyte cytokine gene expression in septic and nonseptic neonatal foals

Background

The hypothalamic‐pituitary‐adrenal (HPA) is influenced by the proinflammatory cytokines IL‐6, IL‐1β, and TNF‐α in critically ill humans. Information about the association of cytokines with the HPA axis in neonatal foals is lacking.

Hypothesis/Objectives

The objectives were to describe for hospitalized septic and nonseptic foals (1) temporal changes in blood concentrations of ACTH, and cortisol, and leukocyte cytokine gene expression, and (2) coassociation of these HPA axis hormones with blood leukocyte cytokine gene expression.

Animals

Hospitalized septic foals (N = 15) and hospitalized nonseptic foals (N = 11).

Methods

Blood samples, obtained from study foals at admission (T = 0), and 24 (T = 1), 48 (T = 2), 72 (T = 3), and 96 (T = 4) hours after admission, were processed to isolate RNA from leukocytes and to harvest plasma and serum for hormone assays. Plasma ACTH and serum cortisol concentrations were determined by radioimmunoassay. Leukocyte mRNA expression of IL‐1β IL‐6, IL‐8, IL‐10, and TNF‐α was determined using RT‐PCR.

Results

Cortisol concentrations were greater (P < .05) in foals at admission than at other time points. The expressions of IL‐8 and IL‐10 mRNA were lower (P < .05) at each time point in septic than in nonseptic foals. Among septic foals, ACTH was positively associated (P = .0026) with IL‐6 mRNA expression.

Conclusions

Sepsis influences secretion of the HPA axis hormones and expression of cytokines in foals. A positive association with the HPA axis and IL‐6 expression was detected. The clinical importance of these findings requires additional study.     

植物生长调节剂对海州常山硬枝扦插生根的影响

以海州常山1a硬枝为试材,研究了不同种类和浓度的植物生长调节剂对海州常山硬枝扦插生根的影响.结果表明:2,4-D、IBA、NAA和ABT1均可以促进海州常山硬枝的生根,以200 mg·L-1的ABT1处理的最好,生根率为93.3％,其次是400 mg·L-1的NAA,生根率为92.0％.方差分析表明:不同生长调节剂种类...     

龙眼生长素受体基因TIR1的克隆及表达分析

为进一步明确龙眼生长素受体基因TIR1的结构和功能,本试验采用RT-PCR和RACE-PCR对龙眼胚性愈伤组织2个TIR1基因(分别命名Dl TIR1-1和Dl TIR1-2)进行克隆,并进行生物信息学和表达分析。研究结果表明:Dl TIR1-1全长4 343 bp,包含ORF 1 755 bp,编码584个氨基酸(Gen Bank登录号:KR558759),而Dl TIR1-2全长2 821 bp,包含ORF 1 926 bp,编码641个氨基酸(Gen Bank登录号:KR558760)。生物信息学分析结果表明,Dl TIR1-1和Dl TIR1-2理化性质较为一致,均属于不稳定蛋白,不含信号肽,具有跨膜螺旋;亚细胞定位于细胞质中,分别含有31个和45个蛋白磷酸化位点;系统进化树分析显示,Dl TIR1-1与十字花科的亚麻荠和甜菜处于同一分支,而Dl TIR1-2与甜橙和胡杨等木本植物保持较近的遗传距离。q PCR结果表明,Dl TIR1-1和Dl TIR1-2在龙眼体胚发生过程中和不同组织器官中的表达模式较为一致,且在非胚性愈伤组织、根和花中表达量最高;此外,在一定的浓度范围内,IAA、ETH、ABA和GA3均能适当提高龙眼TIR1的表达量,而添加Me JA却明显抑制TIR1的转录。上述结果表明,Dl TIR1-1和Dl TIR1-2可能具有相似功能,且均参与龙眼非胚性愈伤组织形成、根系分化以及花器官发育,此外龙眼生长素信号转导途径可能受多种植物激素调控。     

不同产奶量和乳蛋白率奶牛的血液生化和激素水平分析

试验旨在探究奶牛自身生理代谢与产奶量(MY)和乳蛋白率(MP)的关系。从饲喂相同日粮的287头经产、泌乳中期荷斯坦奶牛中分别选取高、低MY牛各20头,高、低MP牛各20头,探究血液生化参数和激素水平的差异;结合287头奶牛的MY、MP与血液生化参数、激素的关联结果,挖掘影响MY和MP的关键生理代谢。结果表明:高MY牛血液中总蛋白、白蛋白和总胆固醇浓度高于低MY牛(P<0.05),而血尿素氮、胰高血糖素、胰岛素样生长因子-1和瘦素浓度低于低MY牛(P<0.05);高MP牛的血尿素氮和白蛋白浓度高于低MP牛(P<0.05),高低MP牛的血清激素无显著差异;关联分析显示,上述差异指标中总胆固醇与MY正相关(P<0.01),血尿素氮与MY负相关(P<0.05);血尿素氮与MP正相关(P<0.05),总蛋白与MP负相关(P<0.01)。综上,在相同的日粮和管理条件下,氮代谢在奶牛MY、MP合成中均发挥重要作用,并且MY可能受能量供应和奶牛自身分泌激素的调控。     

植物花药开裂机制研究进展

花药开裂是花药发育后期的一个重要特征。在生产上当作物花药开裂异常时,就会直接影响授粉受精的完成而影响作物的产量。本文结合植物花药发育的过程,从花药的各个组织结构、细胞的分化、植物激素和转录因子等方面对花药开裂的机理进行综述,并提出今后研究的方向。     

几种激素对桑树疏花疏椹的影响

为解决桑树在园林应用中树势衰退和采摘桑椹而破坏桑树及其他园林植物和园林设施的情况,通过三种激素、四种化学药剂对不同时期的桑树进行疏除效果实验,结果显示在盛花期使用300倍-600倍的30%敌百虫对雌花进行疏除,使用300倍-600倍的80%敌敌畏对雄花进行疏除。在幼果期,对疏花效果不好和漏喷而结果的施用200倍-400倍的40%乙烯利进行疏果。可有效疏除花果总量的90%以上,达到疏除园林桑树花椹,利于树势恢复,提高桑树在园林中应用效果。     

芦笋组织培养快繁技术

[目的]探索芦笋的组织培养快繁技术.[方法]利用丰岛芦笋3—4月抽出的嫩茎为外植体,在不同培养基上诱导、增殖和生根.[结果]筛选出芦笋适宜的诱导培养基为MS+1.0 mg/L BA+0.1 mg/L NAA,增殖培养基为MS+0.5 mg/L BA+0.1 mg/L NAA,生根培养基为MS+1.0 mg/L IBA+...     

Postprandial blood hormone and metabolite concentrations influenced by feeding frequency and feeding level in veal calves

This study hypothesized that increased feeding frequency (FF) decreases problems with glucose homeostasis seen at high feeding levels (FL) in heavy veal calves. Effects of FF and FL on hormone and metabolite concentrations were studied in 15 heavy veal calves fed once (FF1; at 12:00), twice (FF2; at 12:00 and 24:00) or four times daily (FF4; at 06:00, 12:00, 18:00 and 24:00). In period 1, all calves were fed at a low FL (FL(low); 1.5 x metabolizable energy requirements for maintenance, ME(m)). In period 2, FF2 and FF4 calves were fed at high FL (FL(high); 2.5 x ME(m)), whereas FF1 calves were still fed at FL(low). Blood was sampled every 30 min from 12:00 to 18:00 and postprandial integrated plasma hormone and metabolite concentrations (AUC(12-18 h)) were calculated. Glucose AUC(12-18 h) increased with increasing FL, but decreased with increasing FF, urea AUC(12-18 h) increased with increasing FL, whereas non-esterified fatty acid AUC(12-18 h) were unaffected by FL and FF. Insulin AUC(12-18 h) decreased with increasing FF and decreasing FL. Glucagon AUC(12-18 h) increased with increasing FL and FF. Growth hormone AUC(12-18 h) decreased, whereas insulin-like growth factor-1 and leptin AUC(12-18 h) increased with increasing FL. Mean thyroxine and 3,5,3'-triiodothyronine concentrations were modified by FF and FL. There were no FF x FL interactions, except for plasma glucose. In conclusion, postprandial hormone and metabolite responses were differentially affected by FF and (or) FL. Glucose and insulin concentrations were maximally increased at high FL and low FF. Hyperglycemia, glucosuria and excessive insulinemia were prevented by increasing FF and decreasing FL.