二甲亚砜对几种淡水鱼精子渗透压及成活率影响的研究

本文研究了淡水鱼类精子在低温冷冻保存时,其渗透压在抗冻ＤＭＳＯ作用下的变化规律,冷冻前精子的渗透压在ＤＭＳＯ作用下最高可达１５３８ｍＯｓｍ／Ｌ与４．５％ＮａＣｌ溶液相等渗,是自然条件下的５倍,解冻后最高仍保持在１３６７ｍＯｓｍ／Ｌ与４．０％ＮａＣｌ溶液相等渗,是自然条件下的４．５倍,渗透压变化（Ｙ）与二甲亚砜浓度（Ｘ）的关系式为Ｙ＝０．１４８Ｘ＋１．２４５,ｒ＝０．８９８（冻前）和Ｙ＝０．１３６Ｘ     

胆酸盐和十六烷基三甲基溴化铵混合胶束形成

实验结果表明,在０．０５ｍＮａＣｌ水溶液中,胆酸钠,ＮａＣ（或脱氧胆酸钠,ＮａＤＯＣ）和十六烷基三甲基溴化铵,ＣＴＡＢ形成了混合胶束。对这两种混合体系,最强的胶束化作用均发生在αＢｉｌｅ＝０．３。水溶液介质中的ＮａＣｌ降低了胆酸盐分子甾环上羟基的亲水性,从而破坏了亲水面结构,ＮａＣｌ还同时促进了两亲分子碳氢组份间的疏水相互作用,因而在０．０５ｍＮａＣｌ水溶液中胆酸盐分子以垂直于胶束表面,将羧基朝向水溶液的方式与ＣＴＡＢ组成混合胶束。由于胆酸盐分子的体积位阻,在它与ＣＴＡＢ的１：１体相溶液中未能生成等比例混合胶束。     

酿酒酵母3——磷酸甘油脱氢酶的诱导,提纯和性质

在ＹＥＰＤ培养中添加ＮａＣｌ,可以诱导酿酒酵母细胞内３－磷酸甘油脱氢酶的形成,当ＮａＣｌ浓度达５％时,酶比活从０．０５Ｕ／ｍｇ提高到０．５Ｕ／ｍｇ;若再限制培养基中葡萄糖浓度在１００ｍｇ／Ｌ以下,酶比活可达到０．８９Ｕ／ｍｇ。酶比活与培养基中的ＮａＣｌ浓度的函数关系式为：Ｓａ＝０．１２９Ｃ＾３－０．０３８Ｃ＾２＋０．０３４Ｃ＋０．０６３。粗酶液经Ｓｅｐｈａｄｅｘ Ｇ－２５凝胶过滤,Ｂｌｕｅ Ｓｅｐ     

非OI群霍乱弧菌在不同理化环境中产生色素的研究

本文报道了理化因素对非ＯＩ群霍乱弧菌的生长及产生色素的影响。实验结果表明,２５℃～３６℃、０％－３％ＮａＣｌ、ｐＨ７．４～９．０;４２℃、１％～３％ＮａＣｌ、ｐＨ５．０—１０．０为最佳生长环境,适宜生长,并有利于色素的产生。     

小麦与高冰草（长穗偃麦草）体细胞杂种株系与其亲本幼苗抗盐 …

利用不同浓度ＮａＣｌ处理高冰草、小麦、小麦和高冰草体细胞杂种Ｆ３代Ⅲ－１、Ⅱ－２的幼苗,５ｄ后观察其形态,计算耐盐系数,测定生长量脯按酸含量,Ｎａ＾＋、Ｋ＾＋、Ｃａ＾＋等生理指标。结果表明,高冰草具有典型耐盐单子叶植物的特征,。亲本小麦属非生植物,抗盐能力较弱,当ＮａＣｌ浓度达０．５％时已有盐害影响,超过后迅速加重甚至死亡,而杂 受害的盐度比小麦高。１．０％以上ＮａＣｌ浓度达０．５％时已有盐害影     

席藻盐适应培养的研究

用０．２ｍｏｌ／Ｌ ＮａＣｌ作选择因子,可直接筛选得到耐０．２ｍｏｌ／Ｌ ＮａＣｌ席藻。在０．２ｍｏｌ／Ｌ ＮａＣｌ培养液中,席藻细胞逐日降解,到第３ｄ达最低点,３ｄ后细胞数上升。细胞降解随ＮａＣｌ浓度提高而加剧。在等渗浓度或等渗浓度以下,席藻能保持慢速增殖。维生素Ｂ１、吲哚乙酸、玉米素、赤霉素都未能提高席藻对盐类的培养适应能力。席藻对不同的盐溶液培养适应性有差异,而对多种盐复合溶液最能适应。     

红豆草耐盐愈伤组织的筛选及植株再生

将红豆草种子在含１．２％ＮａＣｌ的ＭＳ培养基上萌发以消除盐敏感的幼苗,把存活的幼苗下胚轴切段在含１ｍｇ／Ｌ２,４－Ｄ、０．５ｍｇ／Ｌ６－ＢＡ及１．２％ＮａＣｌ的ＭＳ培养基上诱导愈伤组织,通过连续筛选得到可耐受１．８％ＮａＣｌ的愈伤组织,在有０．２ｍｇ／Ｌ ＮＡＡ和１ｍｇ／Ｌ ＩＡＡ存在下该愈伤组织分化出芽,待幼,待幼苗长至３ｃｍ左右时转至含２ｍｇ／ＬＮＡＡ和或ＩＢＡ的１／２ＭＳ培养基上生根。对对照     

大鼠前列腺甾体结合蛋白C3基因CAAT区核内结合蛋白…

为了解结合在大鼠前列腺甾体蛋白Ｃ３基因ＣＡＡＴ区的核区结合蛋白在此基因表达活跃的前列腺中和不表达的肝脏中的异同;我们用肝素琼脂糖柱层析将两种组织的核抽提液分别进行分级分离,用ＤＮａｓｅＩ足迹法和凝胶阻滞法分析表明：（１）所有ＣＡＡＴ区结合蛋白被富集在０．２－０．５ｍｏｌ／Ｌ ＮａＣｌ洗脱液中;（２）在凝胶阻滞谱上的各种蛋白组分能按迁移率的大小分布在不同浓度的ＮａＣｌ洗脱液中;（３）竞争分析表明：在     

乙烯消减盐渍胁迫对苜蓿种子萌发的抑制作用

在无盐条件下,外源乙烯对苜蓿种子萌发有促进作用,但对最终发芽率无影响。盐渍严重抑制苜蓿种子萌发,加入１～５０μｌ／Ｌ（ｖ／ｖ）外源乙烯或０．１～５．０ｍｍｏｌ／Ｌ１－氨基环丙烷－１－羧酸（ＡＣＣ）或５～１００ｍｇ／Ｌ（ｗ／ｖ）乙烯利（ＥＴＨ）均能极显著地减轻ＮａＣｌ对苜蓿种子萌发的抑制作用。激动素（ＫＴ）也有类似作用,并能促进萌发种子的乙烯产生,它与ＡＣＣ一起使用,则对种子萌发和乙烯产生均显示加成作用。在ＮａＣｌ胁迫下,应用乙烯和乙烯利虽有利萌发,但幼芽鲜重和下胚轴长度明显低于无盐对照。     

黑曲霉产木聚糖酶发酵条件的研究

正交设计试验结果表明,黑曲霉（Ａｓｐｅｒｇｉｌｌｕｓ ｎｉｇｅｒ ｍ１２）产木聚糖酶活力达７６．６０ｕ／ｍｌ,合适的产酶发酵条件如下,培养基（ｇ／Ｌ）：麸皮４０,尿素６．６７,ＫＨ２ＰＯ４ １．０,ＭｇＳＯ４．７Ｈ２Ｏ０．５,ＮａＣｌ０．３,Ｔｗｅｅｎ－８０ ３．０,ＣａＣＯ３ ２．０,２８℃,１２０ｒ／ｍｉｎ水浴振荡培养５．５ｄ。     

瓣结鱼含肉率及肌肉脂肪酸、矿质元素的分析

本文测定和分析了瓣结鱼的含肉率及肌肉中脂肪酸和矿质元素组成。结果表明,瓣结鱼平均含肉率为66．91％。瓣结鱼肌肉中共有14种脂肪酸。其中饱和脂肪酸为5种,平均质量分数为39．49％;不饱和脂肪酸有9种,质量分数平均值为58．83％。瓣结鱼肌肉9种矿质元素中,钙等常量元素的平均含量在116．35mg／100g～1313．33mg／100g之间,而铜等微量元素含量的平均值则在0．19mg／100g～5．20mg／100g之间。瓣结鱼肌肉平均钙磷比为1：4．31。相关分析表明,瓣结鱼的含肉率及肌肉中脂肪酸和矿质元素随其生长变化显著。t-检验表明,瓣结龟肌肉中脂肪酸和矿质元素在清水江标本和都柳江标本之间存在着显著性差异。     

Length–weight relationships of Hara hara (Hamilton, 1822), Pangio pangia (Hamilton, 1822) and Setipinna brevifilis (Valenciennes, 1848) from the lower Brahmaputra River,Northeast India

The present study describes the length–weight relationships (LWRs) for Hara hara, Pangio pangia and Setipinna brevifilis from the lower Brahmaputra River in Assam, Northeast India, collected from June 2016 to May 2017, using fishing gears namely cast nets (9′, 1 ⁄ 2″) and gillnets (30 × 0.9 m). No previous data have ever been recorded on LWR for these three species.     

壳聚糖酶的克隆表达与壳寡糖的制备分析

目的:克隆壳聚糖酶基因于大肠杆菌中实现高表达,制备壳寡糖。方法:以枯草芽孢杆菌总DNA为模板扩增壳聚糖酶基因(CSN),克隆至载体pET23a(+)上,转化菌株BL21(DE3)。重组子经0.5 mmol/L IPTG诱导后,SDS-PAGE和质谱检测与鉴定重组酶。酶纯化后水解壳聚糖,薄层色谱分析其水解产物。结果:质谱证明壳聚糖酶(31.5kDa)成功表达,表达量占菌体总蛋白的45%左右。纯化后重组酶浓度为900 mg/L,纯度95%、回收率85%,酶活力为10 000 U/mg。壳聚糖降解产物为壳二糖至壳四糖。结论:原核表达载体pET23a(+)-CSN构建正确,壳聚糖酶表达量与活性高,适用于水解壳聚糖制备壳寡糖。     

国内外蝗害治理技术现状与展望

本文首先概述了国内外蝗虫发生与为害的态势,总结了现阶段我国蝗虫发生与为害的主要特点:即农田飞蝗暴发频繁而且严重,草原土蝗的发生时常造成严重的经济损失,而且侵入城市干扰市民生活,我国与周边国家之间蝗虫过境迁移频繁,使用化学农药污染环境和农产品;分析了国内外蝗虫防治对策与技术的发展现状,重点介绍了应急防治和可持续治理对策、...     

Comparison of BMI and percentage of body fat of Indian and German children and adolescents

Today, serious health problems as overweight and obesity are not just constricted to the developed world, but also increase in the developing countries (Prentice 2006, Ramachandram et al. 2002). Focusing on this issue, BMI and percentage of body fat were compared in 2094 schoolchildren from two cross-sectional studies from India and Germany investigated in 2008 and 2009. The German children are in all age groups significantly taller, whereas the Indian children show higher values in BMI (e.g. 12 years: Indian: around 22 kg/m2; German: around 19 kg/m2) and in the percentage of body fat (e.g. 12 years: Indian: around 27%; German: around 18-20%) in most of the investigated age groups. The Indian children have significantly higher BMI between 10 and 13 (boys) respectively 14 years (girls). Indian children showed significant higher percentage of body fat between 10 and 15 years (boys) and between 8 and 16 years (girls). The difference in overweight between Indian and German children was strongest at 11 (boys) and 12 (girls) years: 70% of the Indian but 20% of the German children were classified as overweight. In countries such as India that undergo nutritional transition, a rapid increase in obesity and overweight is observed. In contrast to the industrialized countries, the risk of overweight in developing countries is associated with high socioeconomic status. Other reasons of the rapid increase of overweight in the developing countries caused by different environmental or genetic factors are discussed.     

Synthesis and turnover of cerebrosides and phosphatidylserine of myelin and microsomal fractions of adult and developing rat brain.

The synthesis and turnover of cerebrosides and phospholipids was followed in microsomal and myelin fractions of developing and adult rat brains after an intracerebral injection of [U-14C]serine. The kinetics of incorporation of radioactivity into microsomal and myelin cerebrosides indicate the possibility of a precursor-product relationship between cerebrosides of these membranes. The specific radioactivity of myelin cerebrosides was corrected for the deposition of newly formed cerebrosides in myelin. Multiphasic curves were obtained for the decline in specific radioactivity of myelin and microsomal cerebrosides, suggesting different cerebroside pools in these membranes. The half-life of the fast turning-over pool of cerebrosides of myelin was 7 and 22 days for the developing and adult rat brain respectively. The half-life of the slowly turning-over pool of myelin cerebrosides was about 145 days for both groups of animals. The half-life of the rapidly turning-over microsomal cerebrosides was calculated to be 20 and 40 h for the developing and adult animals respectively. The half-life of the intermediate and slowly turning-over microsomal cerebrosides was 11 and 60 days respectively, for both groups of animals. The amount of incorporation of radioactivity into microsomal cerebrosides from L-serine was greatly decreased in the adult animals, and greater amounts of the precursor were directed towards the synthesis of phosphatidylserine. In the developing animals, considerable amounts of cerebrosides were synthesized from L-serine, besides phosphatidylserine. The time-course of incorporation indicated that a precursor-product relationship exists between microsomal and myelin phosphatidylserine. The half-life of microsomal phosphatidylserine was calculated to be about 8 h for the fast turning-over pool in both groups of animals.     

Identification and composition of the tonsillar and anal enterococcal and streptococcal flora of dogs and cats

Enterococcus faecalis was the most frequently isolated enterococcal species from anal swabs and tonsils of dogs and cats, although in the anal samples from dogs Ent. hirae was found almost as often as Ent. faecalis. Most Ent.faecium strains from dog tonsils differed from those associated with humans and other animals in that they fermented sorbitol. Typical Ent. avium as well as atypical Ent. avium -like strains were seen in dogs, while the related species Ent. raffinosus was associated with cat tonsils. Enterococcus cecorum also occurred mainly in cats. Certain atypical strains, presumptively identified as Ent. cecorum , shared characteristics with Ent. columbae.
The most frequent streptococcal species in tonsils of cats and dogs were Streptococcus suis and Strep. canis. Streptococcus canis and Strep. bovis predominated in anal swabs. The canine Strep. suis differed from the common porcine strains in fermenting mannitol.
Forty-seven of the 288 isolates examined could not be identified or related to known species. The characteristics of two groups of these bacteria, provisionally called 'Ton 31 group' and 'O7 group' are described.     

白术同源四倍体的诱导和鉴定及其与二倍体过氧化物酶的比较

以白术（Atractylodes macrooephala Koidz.）二倍体组培苗为材料,对其四倍体诱导方法进行研究,共获得45个白术同源四倍体株系,为优良株系的选育提供了材料。此外,还分析比较了其中8个白术四倍体株系与二倍体的过氧化物酶同工酶（POD）的酶谱差异,发现四倍体各株系过氧化物酶同工酶谱比二倍体的均多了Rf0.310的谱带,且总过氧化物酶比活力也发生了很大改变,对探讨白术四倍体优良株系的生理生化机理具有一定的参考价值。