Immunohistochemical study on changes in gill Na+/K+-ATPase α-subunit during smoltification in the wild masu salmon, Oncorhynchus masou

Changes in immunoreactivity of Na⁺/K⁺-ATPase -subunit in gill sections of wild masu salmon (Oncorhynchus masou) during the parr-smolt transformation (smoltification) were compared with changes in gill Na⁺/K⁺-ATPase specific activity. Gill Na⁺/K⁺-ATPase specific activity increased from April and peaked in May. Immunohistochemical analysis, using an antiserum against a synthetic oligopeptide based on the conserved region of the Na⁺/K⁺-ATPase -subunit, revealed that immunoreactivity was confined to chloride cells in the surface layer of primary lamellae and the proximal end of secondary lamellae. The size and number of these cells increased gradually from February to May; however, the number of chloride cells of the secondary lamellae decreased in May. These data suggest that the synthesis of Na⁺/K⁺-ATPase and the proliferation of chloride cells occur prior to the elevation of enzyme activity. Moreover, it is likely the proliferation and hypertrophy of chloride cells on primary lamellae prepare smolts for entry into seawater and migration in the ocean.     

不同形态钾肥对马铃薯产量及品质的影响

采用随机区组设计,研究了在施入等量钾肥的前提下,硫酸钾及氯化钾配施对马铃薯植株生育性状、氨基酸、钾含量等品质和产量及商品薯率的影响.结果表明,等量不同形态钾肥对植株株高和主茎数有一定的影响,对其他生育性状基本无影响;对块茎中蛋氨酸含量无显著影响,对其他类型氨基酸、总氨基酸、还原糖和钾含量有一定影响;对马铃薯产量、经济效...     

Organic chlorine and chloride in submerged paddy soil: a case study in Anhui province, southeast China

Abstract. Efforts to understand the fate of organochlorine compounds in arable soil have concentrated on anthropogenic compounds, in spite of the fact that organochlorine compounds are both produced and mineralized in soil through natural processes. In order to understand the fate of chlorinated pesticides, it is necessary to take account of the natural chlorine cycle. The present study is a first attempt to illuminate the relationship between the natural chlorine cycle and agricultural practices. The concentration and storage of organic chlorine (Cl_org) and chloride (Cl_inorg) were determined in topsoil of a paddy field compared to an adjacent afforested hill at a sampling site in the Meicun area, Anhui Province, China. The concentration of Cl_org, as well as the chlorine-to-carbon ratio, was significantly lower in the paddy field samples than in the forest soil samples. A weak relationship between the concentration of Cl_org and the organic carbon content was observed in the paddy field, in contrast to the observations made in the adjacent forest soil as well as those made in previous studies, which have suggested a positive correlation between organic carbon content and Cl_org. The similarity between our results at the forest site and the previous studies, which have been carried out in temperate regions, suggests that it is the land use rather than the climate that makes the current paddy soil results different. Our results suggest that the contribution of Cl_org to the paddy soil from above-ground litter and from production within the soil are small or negligible compared with the contribution from pesticide application and wet and dry deposition.     

氯化钙对甘薯蛋白乳化特性的影响

【目的】研究不同氯化钙浓度（0.05、0.10、0.15、0.20、0.25 mol?L-1,pH 7.0）对甘薯蛋白乳化特性的影响。【方法】分别对甘薯蛋白乳化液的乳化颗粒平均粒径（d4,3）、乳化活性指数、乳析指数、界面性质（界面吸附蛋白浓度及组成）和流变性质进行测定。【结果】添加0.05 mol?L-1氯化钙后甘薯蛋白乳化活性指数由未添加氯化钙的30.3 m2?g-1显著降低为27.6 m2?g-1,d4,3从4.2 μm增大至4.42 μm（P＜0.05）。然而,随着氯化钙浓度进一步升高（0.10—0.25 mol?L-1）,d4,3显著增大（P＜0.05）而甘薯蛋白乳化活性指数变化不显著（P＞0.05）。此外,添加较高浓度的氯化钙能显著地增加乳化液的乳析指数和初始表观黏度,且界面吸附蛋白的浓度也显著提高（P＜0.05）。SDS-PAGE分析发现,Sporamin A不易被甘薯蛋白乳化界面吸附,且乳化界面和乳化液中均存在＞66 kD的S-S键高分子聚合物。【结论】 钙离子与甘薯蛋白结合能改变其结构,进而影响甘薯蛋白的乳化特性。     

葡萄苗铝-旱交叉适应对水杨酸的生理响应

以‘玫瑰蜜’葡萄苗为试材,预先用氯化铝和水杨酸处理5周后,再用200g/L聚乙二醇(PEG-6000)模拟干旱处理10d,探讨铝诱导葡萄苗对干旱胁迫的交叉适应及铝-旱交叉适应对水杨酸的生理响应。结果表明,预先铝处理可使葡萄幼苗在干旱胁迫下叶绿素a、叶绿素b、叶绿素a+b、类胡萝卜素的质量分数和相对含水量的降低幅度明显减小,使MDA质量摩尔浓度、相对电导率、氧自由基产生速率和过氧化氢质量摩尔浓度的增加幅度明显减小,使SOD和POD活性、可溶性蛋白质和游离脯氨酸质量分数增加幅度明显增大。添加外源水杨酸后,使这种增减幅度进一步加大。其中,以添加50μmol/L水杨酸后效果最明显,使叶绿素a、叶绿素b、叶绿素a+b和类胡萝卜素的质量摩尔浓度及相对含水量的降低幅度进一步变小,使MDA质量摩尔浓度、相对电导率、氧自由基产生速率和过氧化氢质量摩尔浓度的增加幅度进一步变小,使SOD和POD活性、可溶性蛋白质和游离脯氨酸的质量分数增加幅度进一步变大。可见,预先铝处理可诱导葡萄苗对干旱胁迫的交叉适应性,水杨酸对其有明显的促进作用。     

人工培育牛黄对小白鼠离体小肠运动的解痉作用

本文证明培育牛黄对乙酰胆硷与氯化钡所引起的小白鼠离体小肠痉挛有解痉作用。培育牛黄的成份中去氧胆酸具有较强的抗乙酰胆硷与氯化钡作用,其浓度与效应呈直线相关。其成分中的胆酸仅有较弱的抗乙酰胆硷作用,且浓度与效应不呈直线相关,也无抗氯化钡作用。     

氯化钙处理对菠萝黑腐病的防控效果及机制分析

为了降低采后菠萝果实由黑腐病引起的腐烂损失,本文研究了氯化钙处理对黑腐病的防控效果及相关机制。结果表明,1%氯化钙处理对菠萝黑腐病有最好的抑制作用和防治效果。1%氯化钙处理对病菌菌丝生长影响不大,但可明显抑制病原菌的产孢;氯化钙处理明显降低发病果实中多聚半乳糖醛酸甲酯酶（PMG）、纤维素酶（CX）和β-葡萄糖苷酶（CB）的活性,但对多聚半乳糖醛酸酶（PG）活性变化没有明显影响;氯化钙处理明显提高贮藏中后期菠萝果实中过氧化氢（H₂O₂）的含量,明显提高抗病相关酶苯丙氨酸解氨酶（PAL）、多酚氧化酶（PPO）、几丁质酶（CHI）和β-1,3-葡聚糖酶（GLU）的活性。说明氯化钙处理对黑腐病有较好的防控效果,一方面是由于其降低了病原菌的致病性,另一方面是诱导菠萝果实提高了抗病性。因此,适宜浓度的氯化钙处理为菠萝采后黑腐病的绿色防控提供了一条新的途径。     

采前施用钾肥对菠萝果实贮藏特性的影响

为提高果实的贮藏品质,以菠萝品种巴厘(Ananas comosus cv.Comtede Paris)为试材,采用滴灌形式,研究施钾(硫酸钾和氯化钾)对果实贮藏期间可溶性固形物、可溶性蛋白、维生素C、可滴定酸和可溶性糖的影响.结果表明:适量增施硫酸钾能提高果实采收时可溶性糖、可溶性蛋白、可滴定酸、维生素C的含量;延缓果实贮藏中后期可溶性固形物、维生素C和可滴定酸含量的下降,提高可溶性蛋白含量.而增施氯化钾则显著减少了采收时果实可溶性固形物含量,并且不影响贮藏期间果实维生素C含量.因此,施900 kg/hm2硫酸钾处理果实贮藏品质更好.     

铝盐絮凝天然橡胶制备及其性能表征

采用铝盐絮凝天然胶乳,探讨所得生胶的理化性能、硫化特性及其动态力学性能与传统凝固方法之间的差异.结果表明:通过氯化铝与盐酸溶液的互配,能够获得理化性能指标均达标的生胶产品;氯化铝与盐酸混合溶液凝固胶的拉伸强度较高;铝离子的存在有利于提高天然橡胶的加工安全性,使天然橡胶的损耗因子和损耗模量略有升高,但其储能模量降低.通过红外光谱可以看出,铝盐凝固胶蛋白质的特征吸收峰比酸凝固的弱.