海南省瓜菜农药残留监控模式探讨

海南省是我国重要的商品蔬菜生产基地之一,是冬季"菜篮子"最大的生产基地,2007年反季节瓜菜种植面积154万hm2,总产量330万t,出岛量221.17万t,产值62.73亿元.因此,提高海南瓜菜质量安全水平,对蔬菜实行"从农田到餐桌"全程监控,生产优质蔬菜,不仅可以提高蔬菜的竞争力,增加农民收入,更重要的是能确保城乡居民食用瓜菜安全.本文就海南省瓜菜农药残留监控模式,提出了几点思考.     

不同药物及给药途径对仔猪白痢治疗效果的影响

选择自然感染大肠杆菌、拉白色或灰白色稀粪的哺乳仔猪(要求无弱仔和其他疾病)195头为试验动物,以每窝仔猪为单位,随机分成两大组(每组设5个试验组),给药途径选用肌肉注射和后海穴注射药物;观测三九克痢注射液、氟哌酸注射液、恩诺沙星注射液、痢菌净、链霉素等5种药物对仔猪白痢治疗效果的影响。结果表明,肌注的5个实验组即Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ组总有效率分别是75.0%、72.7%、58.8%、68.4%和52.9%(P﹤0.05),穴注的五个实验组即Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ组总有效率分别是77.3%、72.0%、66.7%、73.7%和62.5%(P﹤0.05);肌注组的总有效率66.3%、穴注组的总有效率71.0%。结果表明,三九克痢的疗效与安全性都是最好的;其次是恩诺沙星;后海穴注射药物的疗效更好。     

Effects of noninvasive delayed limb ischemic preconditioning on prognosis of myocardial infarction

AIM: To study the effects of noninvasive delayed limb ischemia preconditioning (NDLIP) on animal cardiac function, myocardial morphology and myocardial apoptosis after myocardial infarction (MI). METHODS: Healthy SD male rats[n=45, weighing (250±10) g] were randomly divided into 3 groups:MI group:the animal model of MI was established by surgical ligation of left anterior descending artery (LAD) after 2 weeks; NDLIP group:after the success of the MI animal model, NDLIP was carried out every other day until the 4th, 6th and 8th weeks; sham group:as the negative control group, the animals were taken heart LAD threading but no ligation. All rats were fed conventionally. At the end of the 4th, 6th and 8th weeks, all rats were made ventricular intubation, and then the hemodynamic parameters were recorded. The blood samples were withdrawn from the abdominal aorta and the serum was separated via centrifugation. The serum contents of Bcl-2 and Bax were measured by ELISA. Left ventricular anterior wall was homogenized. The mitochondrial respiratory chain complexes Ⅰ, Ⅱ, Ⅲ and Ⅳ in the myocardial tissues were detected by ELISA. RESULTS: At the end of the 4th, 6th and 8th weeks, compared with MI group, left ventricular systolic pressure in NDLIP group was significantly increased, while left ventricular end-diastolic pressure in NDLIP group was significantly decreased (both P<0.05). Mitochondrial respiratory chain complexesⅠ, Ⅱ, Ⅲ and Ⅳ in NDLIP group were significantly increased (P<0.05). The serum level of Bcl-2 in NDLIP group was significantly increased and Bax level was reduced remarkably (both P<0.01). CONCLUSION: NDLIP improves the hemodynamic indexes, promotes the mitochondrial respiratory function and inhibits cell apoptosis, thus improving the prognosis of MI.     

不同灌溉方式对北京春茬露地生菜的影响

为了探索适宜于北京春茬露地生菜的灌溉方式,以生菜品种"雷达"为研究对象,设置3个灌溉处理,以常规灌溉为对照,研究不同灌溉方式对生菜生长、品质和产量的影响。结果表明:常规灌溉处理的株高和叶片数显著低于微喷带和边缝式滴灌带处理;边缝式滴灌带处理的单方水产出最高,且其植株硝酸盐显著低于微喷带处理,维生素C含量要显著高于微喷带处理和常规灌溉处理,果实营养价值和安全性相对较高。综合考虑植株生长、品质、产量和单方水产出率等要素,边缝式滴灌带相对适宜春茬露地生菜的生产,其产量667m~2达到了2 797kg,单方水产出率达到31.3kg·m~(-3),单方水产出率比微喷带处理和常规处理分别高20.8%和233.0%。试验还得出了春茬露地生菜各生育时期的作物系数,能够为实现春茬露地生菜的高效生产提供一定的参考依据。     

不同动态水压模式下迷宫流道内颗粒物运动特性研究

采用PTV技术,观测三角函数、三角、台阶、矩形波形动态水压模式下迷宫流道内颗粒物的运动情况,分析不同动态水压模式下迷宫流道内单个颗粒物运动轨迹、运动速度及流体流场,揭示动态水压抗堵塞机理。结果表明:相对于三角、台阶及矩形波形动态水压模式,三角函数波形动态水压模式下颗粒物滞留滞止区内的时间最短,颗粒物的沉积概率最小,水流对颗粒物的输移能力最大;三角函数波形动态水压模式下流道内产生的水流波动效应不断冲击流道滞止区内存在的低速漩涡,加剧了滞止区水流紊动,进入滞止区的颗粒物随水流不断运动,并对滞留甚至沉积在滞止区内的颗粒物发生强烈冲击,使得颗粒物离底悬浮,返回主流区,并迅速通过流道,增大了水流对颗粒物的输移能力,增强了流道的抗堵塞性能。     

马铃薯地上部绿色组织中糖苷生物碱合成调控的研究

为提高马铃薯品种(系)地上部分糖苷生物碱(SGAs)的含量,增强其抗逆性并改良块茎的品质。克隆了马铃薯茄啶鼠李糖基转移酶基因(sgt3)cDNA和1,5–二磷酸核酮糖羧化酶小亚基基因启动子(rbcS P);对sgt3亚细胞定位预测显示,该蛋白不具有叶绿体转运肽、线粒体导肽和分泌信号肽序列,推测可能位于细胞质;将克隆的sgt3 cDNA片段及rbcS重组到pCEPSP载体上,构建了具有草甘膦抗性标记的绿色组织特异表达sgt3基因植物表达载体。通过农杆菌介导法对马铃薯品种‘陇薯3号’和‘夏波蒂’进行转化,共获得了12株抗草甘膦的阳性转基因植株。对转基因植株的目的基因表达水平和SGAs含量分析发现,地上部sgt3基因相对表达量较未转化植株提高1.3~3.0倍,SGAs含量增加20%~37%,而转基因植株的块茎中SGAs含量变化不显著。本研究的结果为进一步培育枝、叶中高SGAs而块茎中低SGAs的马铃薯抗性品种提供了理论依据。     

杂交玉米新品种康农20特征特性及配套栽培技术

康农20是湖北康农种业股份有限公司用自交系FL 706作母本,自交系FL 598作父本组配选育而成杂交玉米新品种.贵州友禾种业有限公司引进,2016年通过贵州省农作物品种审定委员会审定(编号:黔审玉2016003号). 1 品种特征特性 康农20全生育期126 d,与对照黔单16相当.幼苗叶鞘紫色,株型半紧凑,株高281 cm,穗位高108cm.雄穗一次分枝10个左右,最低位侧枝以上主轴长32 cm,最高位侧枝以上主轴长22 cm,雄花护颖紫色,颖基紫色,花药紫色,雌穗花丝浅粉红色.穗长18.6 cm,穗行数16.6行,秃尖1 cm,单穗粒重227 g,籽粒黄色,百粒重40.4 g.半马齿型,穗轴白色.     

高效氯氰菊酯对小鼠卵巢生殖功能的影响及维生素E的干预作用

为探究高效氯氰菊酯 (beta-cypermethrin, β-CP) 对雌性小鼠卵巢生殖功能的影响及维生素E (vitamin E, VE) 的干预作用,将雌性昆白小鼠随机分为6 组:空白对照组 (花生油处理)、β-CP不同剂量 (10、20、40 mg/kg) 处理组、VE保护组 (20 mg/kg β-CP+20 mg/kg VE) 和VE组 (20 mg/kg VE),连续灌胃10 d。灌胃结束后取小鼠卵巢组织,观察组织结构的病理变化,采用免疫组化法、蛋白免疫印迹试验及RT-PCR方法检测卵巢中StAR蛋白含量及casp-3、casp-8、INHα和INHβB 基因mRNA表达的变化。结果显示:与对照相比,10、20和40 mg/kg的β-CP处理均使小鼠卵巢组织结构发生了损伤,使组织中StAR蛋白的浓度分别降低了18.8%、36.3%和40.3%,casp-3基因的表达分别升高了16.0%、26.7%和52.9%,INHα基因的表达分别升高了34.5%、83.6%和228.7%,INHβB基因的表达分别升高了7.5%、39.2%和52.7%;20和40 mg/kg的β-CP处理使得casp-8基因的表达分别升高了27.1%和36.7%。上述处理组与对照组的差异均达显著水平 (P＜0.05)。与 20 mg/kg β-CP处理组相比,VE 保护组的StAR蛋白含量也显著增多 (P＜0.05)。研究表明,β-CP对小鼠卵巢具有毒性作用,这与β-CP抑制StAR蛋白的合成,上调casp-3、casp-8、INHα及INHβB基因的表达有关;添加VE对小鼠卵巢有一定的保护作用,这与VE可减弱β-CP对StAR蛋白合成的抑制作用有关。     

苹果细胞分裂素氧化酶基因MdCKX7.2的克隆及抗性鉴定

采用同源克隆和PCR技术从‘嘎拉’苹果(Malus×domestica Borkh.)中克隆细胞分裂素氧化酶基因MdCKX7.2(基因序列号:MDP0000279125)。该基因含有1 542 bp的完整开放阅读框,编码513个氨基酸。利用Plant CARE数据库对MdCKX7.2启动子顺式作用元件进行预测分析,发现MdCKX7.2启动子序列中存在光、干旱、脱落酸、水杨酸、茉莉酸甲酯等响应元件。基因表达分析发现,‘嘎拉’幼苗中MdCKX7.2的表达明显受干旱和ABA的诱导。通过农杆菌介导的遗传转化获得MdCKX7.2转基因拟南芥植株。抗性试验表明,异位表达MdCKX7.2基因明显提高了拟南芥对干旱胁迫的抗性。拟南芥种子萌发试验表明,在拟南芥中异位表达MdCKX7.2提高了植株对ABA的敏感性,种子萌发率和幼苗鲜质量明显下降,与种子萌发相关基因的表达量明显上调。以上试验结果表明,MdCKX7.2在植物非生物胁迫响应中发挥重要作用。     

All-trans retinoic acid attenuates blood-brain barrier injury induced by cerebral ischemia-reperfusion in rats through JNK/P38 MAPK signaling pathway

AIM: To investigate the effect of all-trans retinoic acid (ATRA) on blood-brain barrier after cerebral ischemia-reperfusion (CIR) injury in rats and its possible role mechanism.METHODS: Male SD rats were randomly divided into sham group, model (CIR) group and CIR+ATRA (10, 30 and 90 mg/kg) groups. The rat model of CIR injury was established by MCAO thread occlusion method. After ischemia for 1.5 h and reperfusion for 24 h, the neurological functional behavioral score, cerebral infarction volume, brain water content and Evans blue content were determined. The activity of matrix metalloprotein-9 (MMP-9) was measured by gelatin zymography. The protein levels of claudin-5, occludin, ZO-1, JNK, p-JNK, P38, p-P38 and MMP-9 in the brain tissues were determined by Western blot.RESULTS: Compared with CIR model group, ATRA at 30 mg/kg significantly improved neurological function, and decreased cerebral infarction volume, brain water content, Evans blue content and the degradation of tight junction proteins in ischemic area (P<0.01). The activity and protein expression of MMP-9 in ischemic brain tissue were decreased (P<0.01). The phosphorylation of JNK and P38 was inhibited and the protein levels of p-JNK and p-P38 were decreased (P<0.01).CONCLUSION: ATRA reduces the damage of brain tissue and the destruction of blood-brain barrier induced by CIR in rats. The protective effect may be related to inhibiting the activation of JNK/P38 MAPK signaling pathway and MMP-9.