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1.
江淮丘陵地区下蜀系黄土母质发育的水稻土油2稻轮作试验表明, 油菜种植期间, 耕层土壤硫主要来源于耕层以下土层的补给, 其次是大气干湿沉降;该时期耕层土壤硫输出主要是油菜吸收, 其次是淋失.油菜种植期间耕层土壤硫输入量小于输出, 导致耕层土壤硫库下降8.76kg·hm-2, 22%来自无机硫库的下降.水稻种植期间, 耕层土壤硫输入主要来自灌溉水, 其次是底土层的补给和大气干湿沉降;而硫输出主要是淋失, 其次是水稻吸收.耕层土壤硫输入量大于输出, 导致耕层土壤硫库增加18.69kg·hm-2, 18%来自无机硫库的增加.全年油2稻轮作期间耕层土壤硫输入量大于输出, 导致耕层土壤硫库增加9.93kg·hm-2, 13%来自无机硫库的增加.  相似文献   

2.
Cellobiose dehydrogenase purified from two different fungal sources was assessed for its ability to remove and/or reduce colour from pulp mill bleach plant effluent. Cellobiose dehydrogenase purified from Phanerochaete chrysosporium was shown to prefer acidic conditions and was consequently used to treat the acid effluent stream discharged from a pulp mill bleach plant, while an analogous enzyme originating from Humicola insolens preferred alkaline conditions, and was applied to the effluent discharged from the caustic sewer of the bleach plant. Both enzyme preparations were able to remove colour from their respective effluent sources to a comparable extent. Up to 50% of the effluent colour was removed within 4 days when treated under optimised conditions. Furthermore, it was also shown that this enzymatic approach was effective at removing colour generated by both softwood and hardwood resources. Mechanistically, it was shown that colour was removed from all molecular weight fractions, and the higher molecular weight material (>300 kDa) was concurrently preferentially degraded. Cellobiose dehydrogenase treatment of effluent did not target phenolic, stilbene, or alpha-carbonyl structures, but did affect the quinone content. Further investigations using model compounds confirmed these results, and subsequently showed that only the para-quinones with low substitution were reduced with cellobiose dehydrogenase.  相似文献   

3.
Arginase from rat fibrosarcoma was purified about 1900-fold and its properties were compared with those of the enzyme from liver and kidney. Arginase from fibrosarcoma was a neutral protein of molecular weight 120,000 with a Km value of 11 mM for arginine. The activation energy was 7.2 kcal/mol and the pH optimum was 10. The fibrosarcoma enzyme was immunologically different from that of the liver. The arginase from fibrosarcoma closely resembled the arginase from the kidney in its electrophoretic, kinetic and immunological properties.  相似文献   

4.
采用微量滴定法测定了10种植物乙醇提取物对金银花蚜虫的生物活性.结果表明,10种植物乙醇提取物对金银花蚜虫均有一定的驱避活性和毒杀作用.在10 mg/mL的浓度下,臭椿、曼陀罗和桂花的提取物对金银花蚜虫的驱避作用较强,其在12 h的驱避率分别为78.74%、77.54%、75.11%;夏枯草提取物的驱避效果最弱,12 h的驱避率为58.53%.随着处理时间的延长,各植物提取物的驱避效果均呈下降趋势;印楝提取物的毒杀活性最强,72 h后的校正死亡率达68.30%;曼陀罗和苦瓜的作用次之,72 h后的校正死亡率分别为66.41%和63.70%;夏枯草提取物的作用最低,72 h后的校正死亡率仅为26.47%.进一步的毒力分析表明,印楝提取物对金银花蚜虫的毒力较强,24h的Lc.值为11.0836 mg,/mL.  相似文献   

5.
Vapour emanating from intact turnip and radish plants contained small amounts of only one component, probably hexenyl acetate, distinguishable from background vapours. From disrupted leaf tissues of cauliflower, turnip, radish and wallflower at 30°, the predominant vapour component was cis-hex-3-enyl acetate, whereas allyl isothiocyanate was the chief component from Brassica juncea. Other minor components were also identified. Apart from isothiocyanates, the only sulphur-containing component identified from these crucifers was dimethyl disulphide which was detected only from cauliflower, particularly in vapour from disrupted curd tissue.  相似文献   

6.
首次对安徽省三种产地的竹黄菌进行了组织分离培养和液体发酵,比较了该菌固体生长状况和液体发酵形成的竹红菌素产量。结果显示,广德卢村的菌种平皿生长速度为0.31cm/d,液体发酵产生的竹红菌素吸光度为0.21;宁国板桥菌种平皿生长速度为0.30cm/d,液体发酵产生的竹红菌素吸光度为0.30;休宁武城的竹黄菌平皿生长速度为1.85cm/d,菌株液体发酵产生的竹红菌素吸光度为O.39。结论表明,休宁武城菌种无论是平皿生长速度还是发酵形成的竹红菌素量都明显优于其它两地的菌株。  相似文献   

7.
The characteristics of C-S lyase in Lentinus edodes (shiitake) were compared with those in Allium sativum (garlic). C-S lyase mRNA from shiitake was hybridized with the garlic C-S lyase cDNA fragment, being almost the same length as that from garlic. The isoelectric point of the C-S lyase from shiitake was between pH 4 and 5, while that from garlic was over a wider range between pH 4 and 8. Different from the C-S lyase from garlic, that from shiitake was not a glycoprotein without being stained by PAS, and was not bound to the anti-garlic C-S lyase antibody. Similar to garlic C-S lyase, shiitake C-S lyase comprised a homodimer, and its molecular mass was 84 kDa. However, the N-terminal amino acid sequences of each subunit of shiitake C-S lyase were totally different from those of garlic C-S lyase.  相似文献   

8.
用超滤、硫酸铵二段盐析法取代等电点沉淀法后,精制破伤风类毒素(精破类)的纯度由807Lf/mgPN提高到1883Lf/mgPN,纯度提高一倍以上。使用双胨培养基取代酪素培养基后,产毒水平由47Lf/ml提高到88Lf/ml(t=6.46,p<0.001);用新法精制后,精破类纯度分别为1949Lf/mgPN及1785Lf/mgPN(t=0.334,p>0.05),引用双胨培养基后可提高产毒水平,但不影响精破类的纯度。  相似文献   

9.
从小麦、油菜、浮萍、番茄、烟草的叶片中分离得到NR-SF。不同植物材料中NR及NR-SF能起交叉反应;不同NR-SF影响NR酶动力学性质相同;不同NR-SF的凝胶电泳谱带显示蛋白和糖蛋白性质。NR-SF广泛存在于植物细胞中。  相似文献   

10.
利用11对多态性ISSR引物对2014-2016年间采自山东、江苏、浙江、河南及海南等5省的60个玉米多堆柄锈菌菌株进行了种群遗传多样性分析。结果表明,分离自山东的玉米多堆柄锈菌菌株的遗传多样性丰富,多态性百分率( P)达96.34%,与江苏、浙江、河南锈菌种群具有较高的相似性,遗传距离相对较近,其中与江苏的群体遗传相似系数最高(GS=0.7829),遗传距离最近(GD=0.2447),而与分离自海南的锈菌种群相似性最低(GS=0.0148),遗传距离最远(GD=4.2999)。在相似性系数0.74水平上,供试60个菌株被划为3个群和多个亚群组,各群和亚群间表现出较明显的年度与地理分布上的差异。2015年采集的菌株之间 Gst值为0.8694,2015与2016年采集的菌株群体间的 Gst值为0.4562,说明病菌的遗传变异不仅表现在地域上,也体现在年度间。基于ISSR标记分析,作者认为发生在山东省的玉米南方锈病其初侵染菌源不是来自我国周年发生玉米南方锈病的海南省,而最有可能来自同样能越冬的菲律宾或我国台湾地区。  相似文献   

11.
The spontaneous and potassium-stimulated release of endogenous taurine and gamma-aminobutyric acid (GABA) from cerebral cortex and cerebellum slices from adult and developing mice was studied in a superfusion system. The spontaneous release of GABA was of the same magnitude in slices from adult and developing mice, but the spontaneous release of taurine was considerably greater in the adults. The potassium-stimulated release of GABA from cerebral cortex slices was about five times greater in adult than in 3-day-old mice, but the potassium-stimulated release of taurine was more than six times greater in 3-day-old than in adult mice. In cerebellar slices from 7-day-old mice, potassium stimulation also evoked a massive release of taurine, whereas the evoked release from slices from adult mice was rather negligible. Also in cerebellar slices the potassium-stimulated release of GABA exhibited the opposite quantitative pattern. The stimulated release of both GABA and taurine was partially calcium dependent. The results suggest that taurine may be an important regulator of excitability in the developing brain.  相似文献   

12.
The pH optimum of the ATPase activity in plasma membranes from Saccharomyces cerevisiae NCYC 431 from 8 h cultures was around 6.5 and that in membranes from organisms from 16 h cultures near 6.0. The Km[ATP] of the enzyme was virtually unaffected by the age of the culture from which organisms were harvested, although the Vmax of the enzyme in membranes from organisms from 8 h cultures was higher than that for organisms from 16 h cultures. Ethanol non-competitively inhibited ATPase activity in membranes, although the inhibition constant for the enzyme from organisms from 8 h cultures was lower than that from organisms from 16 h cultures. Glycine accumulation by the general amino acid permease was non-competitively inhibited by ethanol. Inhibition constants were virtually the same for glycine uptake by deenergized organisms from 8 h and 16 h cultures, but under energized conditions the value was greater for organisms from 16 h rather than 8 h cultures. The data indicate that inhibition of plasma-membrane ATPase activity by ethanol could account, at least in part, for inhibition of glycine accumulation by ethanol.  相似文献   

13.
在室内条件下通过将红火蚁Solenopsis invicta Buren异巢不同品级的个体置于同一容器中,对红火蚁的巢间相容性进行研究。结果表明,蚁后与异巢幼蚁共处时,异巢幼蚁的羽化率为33.3%,与对照处理的38.3%(蚁后与同巢幼蚁共处)无显著差异。工蚁与异巢幼蚁共处时,异巢幼蚁的羽化率为53.7%,与对照处理的72.2%(工蚁与同巢幼蚁共处)无显著差异。蚁后与异巢工蚁共处时,异巢蚁后的存活率为45%,与对照处理的61.7%(工蚁与同巢蚁后共处)无显著差异。有翅繁殖雌蚁与异巢工蚁共处时,异巢工蚁的存活率为86.7%与对照处理的99.4%(工蚁与同巢有翅繁殖雌蚁共处)存在显著差异;异巢有翅雌蚁的存活率为22.2%,与对照处理的88.9%(工蚁与同巢有翅繁殖雌蚁共处)存在显著差异。由此可见,同区域内红火蚁异巢各品级间存在一定程度的相容性,并巢行为有可能发生。  相似文献   

14.
采用随机完全区组设计对5年生麻疯树Jatropha curcas种源林进行结实性调查。结果表明,不同种源麻疯树单株产种量有不同程度的差异,云南元阳种源最高,达218.96 g,四川盐边种源最低,仅为48.42 g。不同种源麻疯树种子平均含油率也有所不同,广西隆林种源最高,达42.80%,贵州望谟种源最低,为37.23%。单株产种量与种源地纬度、年均气温显著相关,而与种源地无霜期极显著相关,其中与纬度为负相关,与年均气温、无霜期为正相关,说明纬度较低、气温较高和无霜期较长的种源在福建平和县的单株产种量高。而种子平均含油率与各地理气象因子之间没有显著相关性。根据单株产种量和种子平均含油率聚类分析,分别将9个种源分成优、良、中、差4个不同的类别,综合来看,云南东南部和广西西北部可能是麻疯树的优良种源区,该区域内的5个种源,单株产种量达147.43 g,种子平均含油率达41.07%。  相似文献   

15.
利用6044×01-35构建的重组自交系(RIL)群体为试验材料,对小麦粒重性状进行发育动态QTL分析。结果表明,在小麦花后子粒灌浆的7个不同时期,两个试验点共检测到16个与粒重性状相关的QTL。其中开花后20d检测到的单穗粒重QTL位于2A染色体上,解释率达12%,遗传效应超过10;两环境下控制千粒重QTL在7个时期均被检测到。花后的各个时期均能在Xgwm448-Xgpw7399标记区间定位到千粒重QTL。其中花后10d检测到1个千粒重QTL,位于2A染色体的Xgwm448-Xgpw7399标记区间,解释较大的表型变异,达到18%。Qtl8、Qtl13和Qtl14均定位在Xgwm448-Xgpw7399标记区间的同一位置,共同解释11%的表型变异。花后20d和花后25d均检测到1个QTL,位于2A染色体的Xgwm372-Xgwm95标记区间的不同位点,均能解释4%的表型变异。花后40d检测到1个QTL,位于1D染色体的Xwmc93-Xgpw2224标记区间,解释1%的表型变异。从连锁群的位置上看,控制千粒重的QTL主要集中在2A染色体的Xgwm448-Xgpw7399标记区间,这是一个控制千粒重QTL的富集区域,以期进行精细定位和图位克隆。  相似文献   

16.
Summary Human S-protein is a serum glycoprotein that binds and inhibits the activated complement complex, mediates coagulation through interaction with antithrombin III and plasminogen activator inhibitor I, and also functions as a cell adhesion protein through interactions with extracellular matrix and cell plasma membranes. A full length cDNA clone for human S-protein was isolated from a lambda gt11 cDNA library of mRNA from the HepG2 hepatocellular carcinoma cell line using mixed oligonucleotide sequences predicted from the amino-terminal amino acid sequence of human S-protein. The cDNA clone in lambda was subcloned into pUC18 for Southern and Northern blot experiments. Hybridization with radiolabeled human S-protein cDNA revealed a single copy gene encoding S-protein in human and mouse genomic DNA. In addition, the S-protein gene was detected in monkey, rat, dog, cow and rabbit genomic DNA. A 1.7 Kb mRNA for S-protein was detected in RNA from human liver and from the PLC/PRF5 human hepatoma cell line. No S-protein mRNA was detected in mRNA from human lung, placenta, or leukocytes or in total RNA from cultured human embryonal rhabdomyosarcoma (RD cell line) or cultured human fibroblasts from embryonic lung (IMR90 cell line) and neonatal foreskin. A 1.6 Kb mRNA for S-protein was detected in mRNA from mouse liver and brain. No S-protein mRNA was detected in mRNA from mouse skeletal muscle, kidney, heart or testis.  相似文献   

17.
西藏土壤中铜含是及分布   总被引:2,自引:0,他引:2  
1 引  言目前 ,西藏的生态环境基本保持原生状态 ,是至今地球上受人类活动影响和污染最少的地区之一 .所以 ,西藏是进行生态环境本底调查和表生地球化学研究最为理想的场所 .西藏的土壤中Cu含量数据 ,不但有助于进一步研究西藏高原表生环境中Cu的地球化学特征 ,而且还可以为这一地区环境监测与评价等提供基础信息和依据 ,也可以成为全国乃至全世界土壤生态环境背景的永久性参比资料 .2 材料与方法2 1 供试材料样品采自北起唐古拉山 ,南至亚东、樟木、吉隆、普兰 ,东从金沙江 ,西到班公错—除羌唐高原北部以外的西藏广大地区 ,共计…  相似文献   

18.
本实验取10只Wistar大鼠的睾丸和附睾,睾丸石蜡切片,附睾精子涂片后用苯胺蓝染色显示赖氨酸含量。结果是睾丸生精小管中精原细胞和精母细胞染色较深即赖氨酸含量较高,精子细胞和精子染色渐淡即赖氨酸含量降低,而附睾精子显示,在附睾头部的精子染色较深,附睾尾部的精子几乎不着色,应用显微分光光度计测定附睾精子,计算出头部的精子赖氨酸含量在1左右,尾部的精子赖氨酸含量接近于零。本实验还检测了10例正常人及10例不育者精子的赖氨酸,结果为正常人精子的赖氨酸含量较低,不育者精子赖氨酸含量高且畸形率也高。提示精子赖氨酸含量高是核蛋白转型异常的征象,可能是男性不育的一个重要原因。  相似文献   

19.
多莉,第一例大型克隆哺乳动物,由一只称为FinnDorset的6岁母羊乳腺体细胞的基础生命物质经细胞核转移等操作而产生。成果公布后,持怀疑观点的学者提出,提供体细胞的母羊是否本身处在妊娠状态?推测多莉是由胚胎细胞产生,并非体细胞本身克隆所致。由于6岁的母羊死于1995年,只能用其冷冻保存的乳腺组织在Hannah研究中心进行细胞群体的分析。首先,用微卫星扩增技术,以三套引物进行测定;其次,进行DNA指纹分析来断定供体体细胞起源,以确定多莉的真实性。最后证实多莉来自成年母羊乳腺的体细胞。  相似文献   

20.
Characteristics of membrane-associated ATPase from commercial Hawaiian varieties of sugarcane ( Saccharum spp. hybrids) were investigated in preparations from sugarcane cell suspension culture and from stalk tissues of the intact plant. In order to examine comparable preparations, protoplasts and vacuoles, in turn, were obtained from both sources. ATPase from preparations of crude protoplast membranes and tonoplast had a pH optimum of 6 to 6.5. The relative effectiveness of divalent cations in stimulating ATPase was Mg2+ > Mn2+≥ Co2+ > Ca2+≥ Zn2+. Enzyme activity was not stimulated by K+, nor by other monovalent cations. Protoplasts and vacuoles from both sources showed significant acid phosphatase activity. Acid phosphatase activity was inhibited by molybdate, but ATPase activity was unaffected. Membrane preparations from protoplasts contained inorganic pyrophosphatase, but enzyme activity was low or not present in tonoplast preparations. Cell suspension and stalk tissue preparations hydrolyzed a large number of nucleoside di- and triphosphates. The hydrolysis is most likely due to a series of enzymes rather than a single enzyme. ATPase from protoplast and tonoplast preparations was inhibited 30–50% by diethylstilbestrol and sodium ortho-vanadate and was unaffected by ionophores. This study illustrates the complexity of phosphohydrolase activities in membrane preparations from sugarcane. The study, however, also illustrates substantial similarity in the behavior of these enzymes, whether they are derived from the plant itself or from cell cultures originating from comparable tissues of the plant.  相似文献   

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