双低优质油菜应用硒矿粉对富硒效果的影响

对中油杂2号、中双9号两个双低优质油菜品种施用3种不同含硒量的富硒矿粉,结果表明:①应用富硒矿粉能够提高双低优质油菜的植株含硒量,3种硒矿粉处理的油菜植株含硒量为0.1137～0.1352mg·kg-1,比对照增加0.0600～0.0815mg·kg-1,平均增128.68%;②高含硒量富硒矿粉的效果优于低含硒量的矿粉,但施用含量为1494mg·kg-1矿粉的油菜植株含硒量仅比含量为104mg·kg-1矿粉高18.91%,这说明较低含量的矿粉同样具有应用价值;③油菜不同时期的含硒量不同,苗期最少、后期较高,这说明硒元素在油菜中也存在着一个积累过程;④不同遗传基础油菜品种的聚硒效果不同,中油杂2号富硒效果优于中双9号,两者在苗期的差别较大,花期、成熟期的差别较小。     

富硒水溶肥对猕猴桃增硒及增产的效果

为探索硒肥对猕猴桃的增硒及增产效果,于2016年选用"康熙宝"富硒水溶肥在湘西自治州凤凰县"红心猕猴桃"品种上进行了叶面喷施试验。结果表明,喷施康熙宝富硒水溶肥(幼果期和壮果期2次喷施,每次用水溶肥100 m L对水100 kg/667m~2)的处理比对照(只喷等量清水和不喷硒肥及清水)平均增硒0.026 mg/kg,含糖量降低0.4~0.5个百分点,含酸量比对照下降0.03个百分点,糖酸比提高了0.8~1.0,可溶性固形物提高0.9%;平均增产6.8%~8.6%,增产效果达到极显著水平。经农业部检测,猕猴桃含硒量达到湖南省地方标准《富硒产品硒含量标准》。说明施用康熙宝富硒水溶肥对红心猕猴桃的增硒和增产效果显著,可大面积推广应用。     

不同高粱品种对硒的响应

为明确不同高粱品种富硒能力的差异,筛选富硒能力较强的优质高粱品种,以山西省主栽的7个高粱品种为材料,在田间试验条件下,在高粱开花期通过叶面喷施硒肥,研究不同施硒量对高粱籽粒产量和富硒能力的影响。结果表明,开花期叶面喷施外源硒能够显著提高各高粱品种籽粒硒含量,且随着喷施硒剂量的增大高粱籽粒硒含量增加;无论喷硒与否,各高粱品种籽粒硒含量均存在显著性差异,其中,不喷硒条件下,7个高粱品种中以晋糯3号、晋杂22号籽粒硒含量较高,分别为0.160,0.142 mg/kg;在摄入硒的安全范围内,开花期亚硒酸钠喷施剂量以80 mg/kg最适宜,品种中晋糯3号富硒效果最好,籽粒硒含量达0.296 mg/kg,晋杂22号次之,籽粒硒含量达0.277 mg/kg,晋糯3号和晋杂2号籽粒硒含量约为对照的2倍,均达到谷物富硒标准。高粱开花期叶面喷施亚硒酸钠对各品种产量及其构成因子影响不大。因此,建议在山西省的土壤和气候条件下,选择晋糯3号和晋杂22号进行富硒高粱的生产。     

Polychlorinated biphenyls: toxicity to certain phytoplankters

The growth rates of two species of marine diatoms were reduced by polychlorinated biphenyls (PCB's), widespread pollutants of the marine environment, at concentrations as low as 10 to 25 parts per billion. In contrast, a marine green alga and two species of freshwater algae were not inhibited at these or higher concentrations. The sensitivity of these species to PCB's paralleled their sensitivity to DDT [1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane].     

解硒菌9906-5B解硒率的响应面分析

筛选得到一种解硒菌9906-5B,利用含单质硒的煤矸石生产亚硒酸钠,以便有效防止化学法提取硒造成的环境污染。在培养基中加入单质硒,利用解硒菌9906-5B,根据单因素结果设计它的响应面试验。运用SAS软件对解硒因素参数进行统计分析,探讨单因素条件下9906-5B的解硒效果。结果表明,解硒菌9906-5B在pH 6.0温度30℃解硒菌发酵28 h条件下,解硒率达到79.10%。     

Speech: relation of nonfluency to information value

In spontaneous speech and oral reading of stutterers, likelihood of nonfluency occurring on any word is not related to the amount of information carried by that word. The same is true for spontaneous speech of normal speakers. Previous contrary findings can be accounted for by the relationship between information value and word length.     

Metacontrast: its relation to evoked potentials

Electrophysiological correlates of metacontrast were studied by means of averaged evoked potentials recorded from the scalp in man. Under conditions in which the brightness of the first of two successive stimuli appears diminished there is no accompanying attenuation of the evoked potentials to that stimulus. The results suggest that the amplitude and latency of evoked potentials correlate with stimulus intensity but not with brightness.     

不同水平甜菜碱和蛋氨酸对肉鸡生产性能的影响

研究了肉鸡日粮中含不同水平甜菜碱和蛋氨酸组合对肉鸡采食量、增重和胴体性状的影响。试验选用AA肉仔鸡504只,采用单因子试验设计,随机分为7组,每组72只,试验4次重复。分别饲喂对照日粮、不同蛋氨酸和甜菜碱水平组合处理日粮。试验结果未发现甜菜碱对蛋氨酸有替代作用,但不加蛋氨酸或仅加0．05％的甜菜碱导致单位增重的耗料量增高。甜菜碱对蛋氨酸的替代作用可能会受到饲养条件、日粮背景和动物对象等因素影响。     

Obesity: evidence of decreased secretion of glucagon

The increase in concentration of glucagon in plasma caused by infusion of alanine was reduced in obese subjects as compared to that in nonobese control subjects. This was true when the subjects were in the postabsorptive state as well as after an 84-hour fast, at which time the basal glucagon concentration had risen in the nonobese subjects, but remained unaltered in the obese group.     

Moonquakes: mechanisms and relation to tidal stresses

Observed features of moonquakes are combined with theoretical calculations of the tidal stresses to interpret the moonquake mechanisms. Tidal stresses, together with a postulated ambient tectonic stress, are sufficient to explain the depth, periodicity, and polarity reversal of moonquakes. Both of these stresses are small (on the order of 1 bar) and consistent with the small magnitudes of moonquakes.     

Copper: relation to penicillamine-induced defect in collagen

When rats were depleted of copper by administration of a copperdeficient diet, no abnormalities developed in dermal collagen. In contrast, marked changes were produced by penicillamine although the degree of copperdeficiency induced by the drug was less. Large additions of copper to the diet failed to prevent the penicillamine-induced collagen defect when the drug was given parenterally. The effect of penicillamine on soft-tissue collagen appears to be unrelated to its copper-chelating properties.     

硒钴配施对番茄产量、番茄红素及硒、钴含量的影响

采用盆栽试验研究了硒钴配施对番茄产量、番茄红素、番茄果实中硒、钴含量以及土壤中有效硒、钴含量的影响,结果表明,单施硒对番茄产量无明显影响;单一施钴处理时,番茄产量随施钴量的增加而增加;Co2(16 mg/kg)与Se2(0.6 mg/kg)或Se3(3 mg/kg)配施可显著提高番茄的产量,与对照相比,分别提高了14.1%和15.9%。单一施硒和单一施钴以及硒钴配施条件下均可提高番茄中番茄红素的含量。单一施硒和硒钴配施均可明显地提高番茄中硒和土壤中有效硒的含量。单一施钴以及硒钴配施可明显提高番茄中和土壤中有效钴的含量。     

硒在畜禽营养中的应用及发展前景

硒是谷胱甘肽过氧化物酶（GPH～Px）活性成分，是人类必需的微量元素。它能调节机体免疫功能，提高动物的繁殖性能，并具有抗氧化作用。     

硒对油菜镉中毒缓解作用的研究

采用盆栽试验模拟污水灌溉的方式,研究了油菜在镉污染情况下,施用硒做缓解剂对油菜生物量、镉蓄积量及土壤滞留量的影响。结果表明:硒对油菜镉污染具有一定的缓解作用。对照空白试验组,低浓度镉浇灌的油菜生长情况较好,高浓度镉浇灌油菜生长情况较差;随着镉溶液浓度的增大,土壤及油菜中镉含量均随之增大;在一定范围内,随着缓解剂硒浓度的增大,油菜镉中毒的减缓效果逐渐提高,而土壤中镉积蓄程度变化不明显,当硒的浓度为0.5 mg/L时,油菜体内镉含量较对照分别下降28.05%(低镉)和31.09%(高镉)。     

敌敌畏对蚯蚓的急性毒性试验

采用滤纸接触法和自然土壤法研究了有机磷农药敌敌畏对蚯蚓的急性毒性效应,结果显示,用滤纸接触法测得敌敌畏对蚯蚓的LD50为0.14g/L,自然土壤法测得敌敌畏对蚯蚓的LD50为1.11g/L,自然土壤法中敌敌畏对蚯蚓的毒性相对较低,原因可能是自然土壤中成分复杂,敌敌畏或其降解产物与其中某些成分结合,从而降低了敌敌畏的毒性所至。     

Optomotor responses to monocular stimulation: relation to visual system organization

Results of tests on 4 mammalian, 19 reptilian, and 17 avian species confirmed the prediction that lack of optomotor response to monocular optokinetic stimulation in one of the two horizontal directions would correlate with afoveate retinal organization, whereas consistent optomotor responses to monocular stimulation in either horizontal direction would correlate with foveate organization.     

Electrical output of lizard ear: relation to hair-cell population

Cochlear potentials measured in several species of lizard show a close correlation between maximum electrical output and number of hair cells, whereas there is no uniform relation to sensitivity. These results are interpreted as indicating structural differentiation and frequency discrimination in spatial terms in the more advanced lizard ears.     

高温胁迫下萝卜幼苗对硒的生理响应分析

高温胁迫下硒对优白1号和白玉春萝卜幼苗生理生化特征影响的盆栽试验结果表明:低浓度硒(≤0.9 mg/kg)提高了叶片总叶绿素、可溶性蛋白、可溶性糖以及丙二醛(MDA)含量,这说明在一定浓度范围内的硒可以缓解高温胁迫对萝卜幼苗的伤害作用,促进幼苗的生长和耐热性的提高。     

硒对日本沼虾耐受亚硝酸钠胁迫的作用

[目的]研究亚硝酸钠胁迫下饲料中添加适量的有机硒（富硒酵母）对日本沼虾抗氧化酶活性的影响。[方法]在饲料中添加适量的有机硒,测定虾体肌肉中超氧化物歧化酶（SOD）活性。[结果]SOD活性随着亚硝酸钠浓度的增加先升高后降低,试验组沼虾的SOD活性高于无硒对照组。[结论]在饲料中添加适量浓度的有机硒后能够增强SOD活性,而且有助于增强日本沼虾机体的抗氧化能力。     

Selenium: biochemical role as a component of glutathione peroxidase

When hemolyzates from erythrocytes of selenium-deficient rats were incubated in vitro in the presence of ascorbate or H(2)O(2), added glutathione failed to protect the hemoglobin from oxidative damage. This occurred because the erythrocytes were practically devoid of glutathione-peroxidase activity. Extensively purified preparations of glutathione peroxidase contained a large part of the (75)Se of erythrocytes labeled in vivo. Many of the nutritional effects of selenium can be explained by its role in glutathione peroxidase.