欧洲鹅耳枥光响应曲线模型拟合与应用

为筛选出欧洲鹅耳枥(Carpinus betulus)及其4个品种(Carpinus betulus‘Albert Beekman’、Carpinus betulus‘Frans Fontaine’、Carpinus betulus‘Lucas’、Carpinus betulus‘Fastigiata’)光响应曲线拟合的最优模型,并找出北京和南京两地光合能力较强的品种,采用直角双曲线模型、非直角双曲线模型及直角双曲线修正模型对欧洲鹅耳枥及其4个品种在北京和南京两地的光响应曲线进行拟合。研究发现,(1)欧洲鹅耳枥及其4个品种光响应模型拟合效果依次为直角双曲线修正模型非直角双曲线模型直角双曲线模型;(2)北京地区欧洲鹅耳枥及其4个品种的光合能力由强到弱依次为C.betulus‘Fastigiata’C.betulus‘Albert Beekman’C.betulus‘Lucas’C.betulus‘Frans Fontaine’C.betulus,南京地区光合能力由强到弱依次为C.betulus‘Fastigiata’C.betulusC.betulus‘Lucas’C.betulus‘Albert Beekman’C.betulus‘Frans Fontaine’。(3)C.betulus‘Lucas’、C.betulus‘Fastigiata’和C.betulus更适宜在南京地区生长,而C.betulus‘Albert Beekman’、C.betulus‘Frans Fontaine’更适宜在北京地区生长。     

试析我国农业机械化发展应对措施

农业机械是农业生产力的重要内容,也是解放生产力的重要途径,根据多年的工作经验,文章详细分析了我国机械化发展的现状,并论述了我国机械化遇到的制约因素,最后提出相应的措施.     

富硒双歧杆菌南瓜菌粉的研制

为研制成本低且具有合生元效果的富硒双歧杆菌制剂,以南瓜为主要原料,通过响应面法优化最佳培养基配方,考察多种双歧杆菌在最优培养基中的生长情况及富硒能力。研究结果表明,当培养基组成为：南瓜汁浓度16.09%、大豆蛋白胨3.24%、半胱氨酸盐酸盐0.28‰时,动物双歧杆菌01的活菌数可以达到9.37±008 lgCFU/mL,高于在MRS、GMRS、PYG和TPY培养该菌所得的活菌数量。在上述优化南瓜汁培养基中培养,动物双歧杆菌01、婴儿双歧杆菌、长双歧杆菌、青春双歧杆菌、短双歧杆菌、假小链双歧杆菌和动物双歧杆菌BB12的有机硒含量可以达到(13.20±0.39)~(78.11±0.42) μg/g菌体,有机硒转化率为1.76%~6.41%。培养获得的双歧杆菌以南瓜汁和脱脂乳为保护剂,冻干存活率可以达到70.8%±0.5%。研究证明了南瓜果肉作为双歧杆菌增殖和保护基质的潜质,并为富硒双歧杆菌南瓜粉制剂的研制提供了理论依据。     

菜籽粕对异育银鲫免疫应答能力的影响

试验鱼以投喂饲料的不同和是否注射抗原共分为10组,即免疫组:A、B、C、D、E组,免疫对照组:a、b、c、d、e组,饲料对照组:A、a组.饲料试验组B、C、D、b、c、d、e组.其中,饲料对照组以豆粕和鱼粉为基础蛋白源,饲料试验组分别以双低菜籽粕和普通菜籽粕等氮替代对照组中50%(B、b;D、d)和100%(C、c;E、e)的豆粕蛋白,测定异育银鲫血液白细胞和头肾吞噬细胞的吞噬活性、血清溶菌酶活性、血清补体(C3,C4)含量、血清凝集抗体效价及免疫保护率.结果表明:从免疫后21 d开始,饲料试验组E、e、C、c组的各项免疫指标都显著低于相应饲料对照组;在49 d,D、d组的部分免疫指标也显著低于相应饲料对照组;B、b组和相应饲料对照组之间没有显著的变化.免疫组的各项免疫指标均显著高于相对应的投喂相同饲料的免疫对照组.     

GPX4失活通过JNK通路缓解LPS诱导巨噬细胞炎症反应

【目的】研究硒蛋白谷胱甘肽过氧化物酶4(glutathione peroxidases 4,GPX4)失活如何参与调控脂多糖(lipopolysaccharide, LPS)诱导的RAW264.7巨噬细胞炎症反应及其潜在的分子机制。【方法】体外培养RAW264.7巨噬细胞,以DMSO为对照,使用0.1～5.0μmol/L GPX4抑制剂FIN56处理,通过CCK-8法检测细胞活力和Western blotting检测GPX4蛋白表达水平,确定抑制剂最适浓度。将RAW264.7巨噬细胞分为4组：对照组,添加DMSO培养24 h; FIN56(GPX4抑制剂)组,添加0.5μmol/L FIN56培养24 h; DMSO-LPS组,DMSO培养24 h后使用LPS(100 ng/mL)刺激3 h; FIN56-LPS组,FIN56培养24 h后使用LPS刺激3 h。各组细胞经培养后,利用荧光探针2′,7′-二氯二氢荧光素二乙酸酯(2′,7′-dichlorodi-hydrofluorescein diacetate, H₂DCFDA)检测细胞内活性氧(reactive...     

改进微波装置辅助提取猕猴桃根三萜类化合物的研究

应用单因素试验、析因试验和响应面分析法等统计学方法,对自行设计的可以同时控制温度的微波装置辅助提取美味猕猴桃根中具有保肝作用的三萜类化合物的工艺进行了深入研究。试验结果表明：在微波功率一定的情况下,乙醇浓度、提取温度和提取时间的影响最显著,优化得到最佳微波辅助提取工艺参数为乙醇浓度63%,温度47℃,时间为30 min,一次提取率可达85.13%。经验证试验证明,该方法是一种实用的提取方法。     

小麦品种对增强UV-B辐射响应的RAPD分析

在前一研究结果的基础上,选用8个对UV-B辐射耐受性不同的小麦品种(4个耐性品种和4个敏感品种),进一步对其进行RAPD分析。结果表明,8个小麦品种间存在着明显的遗传多态性。聚类分析显示,在遗传距离为0.35的水平上,可将它们明显区分出耐性和敏感两大类,这与其生长响应指数(RI)的判定结果基本一致。4个耐性品种共同具有1500bp(OPA-12)的特征谱带,这一分子标记可能与小麦耐UV-B辐射相关,有待进一步研究。     

Versatile physiological functions of the Nudix hydrolase family in berry development and stress response in grapevine

Nudix hydrolases are widely distributed across all classes of organisms and provide the potential capacity to hydrolyze a wide range of organic pyrophosphates. Although Nudix hydrolases are involved in plant detoxification processes in response to abiotic and biotic stresses, the biological functions of Nudix hydrolases remain largely unclear in grapevine.In the present study, a total of 25 putative grapevine Nudix hydrolases(VvNUDXs) were identified by bioinformatics analysis and classified int...     

响应面法优化灵芝子实体多糖提取工艺及其抗氧化活性研究

为确定灵芝子实体多糖最佳提取工艺,通过单因素实验研究料液比、提取时间、浸提温度及溶剂提取次数对灵芝子实体多糖提取率的影响。在此单因素试验的基础上,采用响应面法对灵芝子实体多糖提取工艺进行了优化。实验结果表明,灵芝子实体多糖浸提的最佳提取条件为液固比50:1,提取时间 60min,提取温度100℃,在此条件下灵芝子实体多糖的提取率为2.96%;体外抗氧化测定结果显示,灵芝子实体多糖对 DPPH、OH自由基的 IC50 分别为 0.67mg/mL和0.46 mg/mL,数据表明灵芝子实体多糖具有极强的抗氧化能力。     

Effect of pidotimod on renal function and inflammatory response in rat IgA nephropathy model

AIM:To explore the effect of pidotimod on the renal function in IgA nephropathy (IgAN) rat model, and to further study whether this effect is related to the inhibition of inflammatory response. METHODS:The SD rats (n=36) were randomly divided into control group, IgAN model group, IgAN with prednisone treatment group and IgAN with pidotimod treatment group, with 9 rats in each group. The IgAN model was induced by consecutive oral administration of bovine gamma globulin (BGG) for 8 weeks followed by injection of BGG through tail vein for 3 d. After the IgAN model was established, the drug was continuously used for 4 weeks. At the end of the treatment, the urine protein, serum creatinine and blood urea nitrogen were examined by an automated analyzer. IgA deposition in the renal tissues was observed by immunofluorescence staining. The mRNA expression levels of renal fibrosis markers transforming growth factor-β1 (TGF-β1) and fibronectin 1 in the renal tissues were detected by RT-qPCR. The mRNA and protein levels of pro-inflammatory cytokines interleukin-1β (IL-1β) and IL-6 in the renal tissues were determined by RT-qPCR and Western blot, respectively. RESULTS:No significant difference of the body weight was observed in different groups. Compared with control group, the content of urine protein, serum creatinine and blood urea nitrogen were significantly increased (P<0.01), whereas those were reversed by pidotimod treatment. The results of immunofluorescence staining showed that pidotimod inhibited IgA deposition in the IgAN rats. Pitomod treatment inhibited the mRNA expression levels of renal fibrosis markers TGF-β1 and fibronectin 1, and the mRNA and protein levels of pro-inflammatory cytokines IL-1β and IL-6 in the renal tissues of IgAN rats. CONCLUSION:Pidotimod alleviates IgAN progression in rats by inhibition of inflammatory response.