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Pineapple guava (Acca sellowiana) syn. Feijoa sellowiana, a Brazilian indigenous Myrtaceae is under domestication in South Brazil. Previous works showed that this species is responsive to somatic embryogenesis and recalcitrant to conventional methods of clonal propagation. In the present work it was evaluated the role of components of culture medium in the induction and development of somatic embryos. The technology of synthetic seeds was also evaluated. Zygotic embryos were inoculated in LPm medium supplemented with 8 mM glutamic acid and 8 mM l-glutamine, 2,4-dichlophenoxiacetic acid (20 μM) and myo-inositol. For conversion of somatic embryos and synthetic seeds it was tested the effect of 6-benzylaminopurine and gibberellic acid combined or not with activated charcoal. The highest values for embryogenetic induction (100%) and number of somatic embryos/explant (113) were observed in the LPm medium supplemented with Glu (8 mM), and 2,4-D. The culture medium supplemented with BA (0.5 μM) and GA3 (1 μM) and activated charcoal (1.5 g L−1) enhanced the conversion of somatic embryos to plantlets. Pre-germinated somatic embryos encapsulated in sodium alginate with BA (0.5 μM) and GA3 (1 μM) developed radicles. The use of synthetic seed was a requisite for the survival of plantlets.  相似文献   
2.
The stability and activity of phytases in the soil environment may be affected by their sorption on soil particle surfaces and by substrate availability with important consequences for P cycling and nutrient bioavailability. This work evaluated the interaction of phytases with goethite, haematite, kaolinite, montmorillonite and two oxisol clays and investigated how this interaction is affected when myo-inositol hexakisphosphate (InsP6) was sorbed on the mineral surfaces. phyA histidine acid phosphatases of fungal origin were used and their ability to release orthophosphate from the InsP6-saturated minerals was evaluated.The phytases showed a high affinity for the mineral surfaces, with a loss of enzyme activity generally being observed over 24 h (up to 95% of the initially added activity). The loss of phytase activity was dependent on the type of mineral, with kaolinite and montmorillonite showing the greatest effect. Retention of enzyme activity was higher with the two oxisol clays, suggesting that the heterogeneous nature of clay surfaces and the presence of endogenous organic matter may limit the inhibition caused by interaction with minerals.In the presence of mineral surfaces saturated with InsP6, the partitioning of enzyme activity between the solution and the solid phase was shifted more towards the solution phase, presumably due to the mineral surfaces being occupied by the substrate. However, phytases were not able to release any orthophosphate directly from InsP6-saturated goethite and haematite, and hydrolysed InsP6 that was desorbed from haematite. Conversely, in the case of kaolinite and of the oxisol clays, where desorption was limited, phytases appeared to be able to hydrolyse a small fraction of the InsP6 adsorbed on the surfaces. These findings suggest that the bioavailability of P from inositol phosphates is governed to a large extent by the mineral composition of soil and by competitive effects for sorption on reactive surfaces among inositol phosphates and phytases.  相似文献   
3.
以龟井(无籽)温州蜜柑和鄂柑1号(有籽)橘为试材,对果实发育成熟过程中果肉游离糖(果糖、葡萄糖和蔗糖)、肌肌醇及钾含量变化进行了测定。结果表明:(1)果实增大初期鄂柑1号果肉果糖和葡萄糖含量明显上升,蔗糖变化小,肌肌醇却趋下降,进入果实增大中后期,蔗糖含量显著上升,其它变化小;而龟井的果糖、葡萄糖和蔗糖均于果实增大初期和中期出现明显积累,肌肌醇除在增大中期出现一峰值外趋于平稳;采前果实发育期两品种总糖含量变化趋势均与各自的蔗糖较一致;(2)采后贮藏期内两品种果肉总糖和肌肌醇含量均趋于稳定,而二者的果糖、葡萄糖和蔗糖含量变化趋势却均趋相反;(3)两品种果肉钾含量均在果实增大期内出现明显上升并居相对较高水平。  相似文献   
4.
Inositol phosphates are abundant organic phosphates found widely in the environment. The sorption and desorption of organic phosphate (Po) are important processes in controlling the mobility, bioavailability and fate of phosphorus (P) in soil and sediment. The desorption characteristics of myo‐inositol hexakisphosphate (IHP) and inorganic phosphate (Pi) from goethite were studied by pre‐sorption of IHP or Pi followed by desorption by KCl, H2O, and citrate. Batch experiments and in situ attenuated total reflectance Fourier transform infrared (ATR‐FTIR) spectroscopy were used to investigate the desorption of IHP/Pi. The desorption percentage of IHP/Pi by citrate was much higher than that by H2O/KCl. The desorption of P by citrate was mainly achieved through ligand exchange, and the desorption increased with decreasing pH. Desorption by H2O was slightly greater than that by 0.02 M KCl because the electrostatic repulsion between the P molecules is larger in H2O. Due to the higher affinity of IHP for goethite than that of Pi, the maximum desorption of IHP was lower than that of Pi. Desorption curves (desorption concentration in solution vs. sorption density) of IHP or Pi on goethite by KCl or H2O was well fitted by an exponential equation, while those by citrate were well fitted by a linear equation. The desorption amounts of P in the first cycle account for more than 58% of the total desorption followed by substantial decreases in the second and third cycles. There was a re‐sorption of Pi from solution in the late stage of desorption by KCl and H2O, resulting in a sharp decrease in desorption. Re‐sorption of IHP did not occur, which is probably due to its poor diffusion into goethite. The initial desorption rate of Pi with KCl and H2O decreased with increasing pre‐sorption time, whereas that of IHP was opposite. This study indicates that strong sorption on and weak desorption of IHP from iron (hydr)oxides may explain the accumulation of IHP in soils.  相似文献   
5.
以龟井(无籽)温州蜜柑和鄂柑1号(有籽)橘为试材,对果实发育成熟过程中果肉游离糖(果糖、葡萄糖和蔗糖)、肌肌醇及钾含量变化进行了测定。结果表明:(1)果实增大初期鄂柑1号果肉果糖和葡萄糖含量明显上升,蔗糖变化小,肌肌醇却趋下降,进入果实增大中后期,蔗糖含量显著上升,其它变化小;而龟井的果糖、葡萄糖和蔗糖均于果实增大初期和中期出现明显积累,肌肌醇除在增大中期出现一峰值外趋于平稳;采前果实发育期两品种总糖含量变化趋势均与各自的蔗糖较一致;(2)采后贮藏期内两品种果肉总糖和肌肌醇含量均趋于稳定,而二者的果糖、葡萄糖和蔗糖含量变化趋势却均趋相反;(3)两品种果肉钾含量均在果实增大期内出现明显上升并居相对较高水平。  相似文献   
6.
许海娟  王锐  魏世勇  方敦  杨小洪 《土壤学报》2019,56(6):1381-1389
制备了蒙脱石-针铁矿复合体(Mt-Goe)和蒙脱石-非/弱晶质氧化铁复合体(Mt-HFO),研究了它们的结构、表面性质及其对无机磷酸盐(Pi)和植酸(IHP)的吸附特性。结果显示,Mt-Goe中少量羟基铁离子进入了蒙脱石晶层间导致其层间距增大,针铁矿颗粒较好地包被在蒙脱石外表面;Mt-HFO中蒙脱石层间则发生了Fe~(3+)水解,生成了(羟基)铁氧化物,并在蒙脱石表面形成非晶质氧化铁颗粒。蒙脱石、Mt-Goe和Mt-HFO的比表面积分别为258.7、185.4和226.4 m~2·g~(–1),其表面分形度、等电点和表面羟基含量均依次升高,pH5.5时的表面Zeta电位分别为–46.1、–13.6和–19.4 mV。3种样品对Pi和IHP的吸附模式以匀质性表面单层吸附为主,Langmuir饱和吸附量(qmax)和吸附亲和力均表现为由大到小依次为Mt-HFO、Mt-Goe、蒙脱石。3种样品对Pi和IHP的动力学吸附过程适合用准二级动力学模型描述,其速率常数由小到大依次为Mt-HFO、Mt-Goe、蒙脱石。与吸附Pi相比,3种样品吸附IHP的动力学速率常数明显减小,吸附量明显增大;Mt-HFO对IHP的吸附速率尤其缓慢,而吸附量远大于对Pi的吸附量。  相似文献   
7.
为研究植酸(IHP)对绿锈转化过程及机制的影响,通过空气氧化法合成碳酸盐绿锈[GR1 (CO32-)],并利用X射线衍射、衰减全反射-傅里叶变换红外光谱、高分辨透射电子显微镜、扫描电子显微镜和能量色散X射线能谱对体系中的固体产物进行分析表征。研究表明:不存在IHP时GR1(CO32-)在5 h左右完全转化为针铁矿,而存在IHP时GR1(CO32-)的转化会受到抑制。在0~0.5mmol·L-1的IHP浓度范围内,GR1 (CO32-)的转化产物为针铁矿,而当IHP浓度高于1.0 mmol·L-1时,GR1 (CO32-)的转化产物为针铁矿和高铁绿锈。IHP对GR1(CO32-)转化机制的影响与其浓度有直接关系,在低浓度IHP(0~0.5 mmol·L-1)条件下,GR1(CO32-)转化过程只涉及溶解-氧化-沉淀(DOP)机制;而高浓度IHP(1.0~5.0 mmol·L-1)体系中,固态氧化(SSO)机制占主导地位,在其转化过程中,一部分GR1(CO32-)通过溶解再沉淀机制转化为针铁矿,一部分GR1(CO32-)通过原位脱质子反应转化为高铁绿锈。此外,在GR1 (CO32-)转化过程中,IHP在GR1 (CO32-)及其转化产物表面会形成内圈络合物和植酸(亚)铁沉淀。总体而言,IHP会抑制GR1 (CO32-)的溶解再沉淀转化机制,阻碍针铁矿的结晶和晶体生长,且抑制作用与IHP浓度呈正相关。  相似文献   
8.
罗晨皓  缪凌鸿  林艳  刘波  戈贤平 《水产学报》2023,47(6):069605-069605
为了探讨不同方法制备的肌醇及其添加量对建鲤生长性能、生理生化以及抗氧化能力的影响,实验以蛋白含量34.64%和脂肪含量7.86%制备基础日粮(C),通过在基础日粮中分别添加400 mg/kg酶促法肌醇(C+400E-MI)和400 mg/kg化工法肌醇(C+400C-MI)配制3种实验日粮,选取当年繁育的健康的建鲤幼鱼[(1.5±0.01) g]进行为期10周的养殖实验。养殖结束后,测定其生长性能、肝脏抗氧化酶活性和炎症相关基因的表达。结果显示,与对照组相比,基础日粮中添加不同制备方法的肌醇均具有提高建鲤幼鱼的特定生长率、蛋白质效率和蛋白质沉积率的作用;能降低血浆中乳酸脱氢酶的含量,有效保护肝细胞。与对照组相比,添加400 mg/kg酶促法肌醇可以显著提高建鲤幼鱼肝脏总超氧化物歧化酶(T-SOD)和谷胱甘肽过氧化物酶(GPX)活性,增加谷胱甘肽(GSH)的含量。添加400mg/kg化工法肌醇能够显著提高建鲤幼鱼肝脏GPX的活性,但同时也显著提高了丙二醛(MDA)的含量。进一步对基因表达的分析发现,2种肌醇的添加均显著降低了建鲤幼鱼肠道中促炎因子IL-6、TNF-α和IL-12在mRNA...  相似文献   
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