低温预处理对水曲柳体细胞胚胎发生的影响

用4℃低温预处理未成熟的水曲柳种子0-30d,取出种子内的合子胚为外植体诱导体胚发生,研究低温预处理影响体胚发生的结果表明：低温预处理过的外植体其体胚发生总数和子叶胚发生数均低于未作低温预处理的;随着预处理时间的延长,畸形胚发生数和发生比率与总的体胚发生数和发生率的变化趋势基本相同;处理20d的正常胚发生数和发生比率的绝对数虽然很低,但远高于不作低温预处理的。说明4℃低温预处理对水曲柳体胚发生没有促进作用,对畸形胚的发生也不能控制,总的来讲,适当的低温处理有一定的改善正常体胚发生的潜力。     

雪花梨和鸭梨果实贮藏特性比较（简报）

采后雪花梨和鸭梨果实于20±1℃下均具典型的呼吸跃变过程。后者采后初期对低温敏感,降温过快,导致早期黑心病.12C 下,一周后每 3d降1C 缓慢降温,直至0±0.5C 可控制早期黑心病的发生。前者直接于0C下贮藏效果好。后者对CO_2也敏感,尤其是果心组织,5％～10％的CO_2处理两周,即可导致严重的果心组织褐变,但小于10％的CO_2对前者较安全,且能获得较好的贮藏品质。     

甘露醇预处理对大麦雄核发育的影响李文泽等:甘露醇预处理对大麦雄核发育的影响

研究了甘露醇预处理对大麦（Ｈｏｒｄｅｕｍ ｖｕｌｇａｒｅ Ｌ．）雄核发育的影响。结果发现,第一,甘露醇预处理比低温预处理和对照能明显地提高花粉存活频率,三者在接种后第８ 天分别为１９．０％ 、８．４％ 和６．６％ 。第二,甘露醇预处理能提高小孢子的质量,抑制淀粉积累,有利于小孢子分裂发育,使发育进度比低温预处理和对照提早２—３ ｄ,而对照和低温预处理的小孢子都不同程度出现淀粉积累,它对发育不利。第三,甘露醇预处理后小孢子的发育途径主要是Ｂ途径,Ａ途径较少。大多数小孢子的细胞核为二倍体,而低温预处理大多数小孢子的染色体数目较少,为单倍体     

低温贮藏过程中溶质和硬质桃冷害发生的生理差异

该试验以溶质型桃品种(中油桃13号、春美和中油桃4号)和硬质型桃品种(中油桃18号、中桃9号和白如玉)为试材,分析桃果实在4℃低温贮藏过程中的品质变化以及乙烯释放规律,探索不同肉质桃果实冷害的发生机制。结果表明:(1)硬质型桃果实的冷害症状主要表现形式是果肉发生褐变,而溶质型桃的冷害症状以果肉木质化和絮败为主。(2)相对室温贮藏而言,短时间冷藏可以抑制溶质型桃果实内源乙烯的释放,但长时间低温冷藏会导致冷害发生,刺激乙烯释放量迅猛攀升;长时间的低温贮藏也会诱导硬质型桃内源乙烯的释放;在低温贮藏期间,毛桃品种果实乙烯释放高峰会比同种肉质类型的油桃品种推迟5～10 d,毛桃相较于油桃对低温的耐受性更强。(3)溶质型桃果实采后软化迅速,但其果实硬度下降速率在低温下受到明显抑制,在冷藏后期还维持在15N上下,而硬质型桃果实硬度在低温和常温贮藏期间受影响较小。(4)不同肉质类型桃果实的可溶性固形物含量在贮藏期间变化幅度均不大。研究发现,不同肉质型桃受到冷害的症状和乙烯释放的模式均不相同,该结果为不同质地的桃果实合理低温贮藏提了供理论依据。     

热激处理对冷藏枇杷果实冷害的生理作用

枇杷(Eriobotrya japonica Lindl.)果实采后经48～52℃、10 min的热激处理,然后2～5℃贮藏,通过对贮藏期间果实冷害级别、呼吸速率、过氧化物酶、过氧化氢酶、苯丙氨酸解氨酶活性和质膜相对透性变化的分析,研究贮前热激处理对冷藏枇杷果实冷害的生理作用.结果表明,2～5℃低温可诱导枇杷果实呼吸速率和苯丙氨酸解氨酶活性异常升高,果实冷害程度与苯丙氨酸解氨酶活性之间呈正相关,相关系数r=0.926.热激处理能降低冷藏条件下(2～5℃)枇杷果实呼吸速率的异常升高,减轻由于低温胁迫造成的果肉细胞膜损伤,提高枇杷果实的过氧化物酶和过氧化氢酶活性,降低苯丙氨酸解氨酶的活性.贮前热激处理有推迟和减轻枇杷果实冷害症状发生、降低果肉低温劣变的作用.贮前热激处理结合低温冷藏是延长枇杷果实贮藏寿命的有效措施之一.     

越冬期间香蕉果穗套袋的防寒效果及其对产量的影响

冬季香蕉果穗用兰色聚乙烯薄膜套袋之后,可提高袋内温度1～5℃,果实低温伤害卑只有1％左右,而未经套袋的达23％～35％,果指长度和径围增加率分别达12％和9％左右,果实产量比对照增加8％～16％。试验结果表明,兰色聚乙烯薄膜套袋是越冬期间香蕉防寒保果和增产的一项有效措施。     

乙醇对‘木纳格’葡萄采后贮藏期间品质的影响

葡萄采收后分别用不同浓度乙醇处理放在低温下贮藏,测定其品质指标的结果表明：40％的乙醇能有效控制葡萄果实的腐烂,对果实可溶性固形物含量则无影响,还可减缓果实硬度和可滴定酸含量下降,以及抑制细胞膜透性的增加,从而提高果实的贮藏品质。     

枇杷害虫发生与防治技术研究

调查研究结果表明,福建枇杷发生常见害虫约35种。叶部主要害虫有枇杷瘤蛾、苹掌舟蛾,在6-8月份发生为害叶片;果实主要害虫有燕灰蝶、长卷蛾,在3-5月份发生为害果实。研究应用90％万灵WP和10％吡虫灵WP防治低龄瘤蛾幼虫,效果分别为92.61％和90.34％;采用喷5％齐螨素结合套袋（牛皮纸）保果能有效控制果蛀虫的为害,防效为96.5％。     

采前低温诱发菠萝果实黑心病

采前低温可诱发菠萝果实黑心病,发病率变化范围为６０％－１００％,低于２１℃的采前低温影响是诱发菠萝黑心病的重要因子之一。在华南菠萝生产区,不同品种对黑心病敏感性的峭同。因此,培育和栽培抗黑心病的菠萝新品种,将是一个控制黑心病腐烂的重要措施。     

冷藏条件下超低氧处理对樱桃果实中乙醇、乙醛和甲醇含量的影响

０℃低温条件下低氧处理促进果实中乙醇和乙醛含量的增加,特别是贮藏１８ｄ以后,乙醇含量提高１８０～３００多倍,乙配合含量高８～９倍。６℃低氧处理果实中挥发性物质积累加快。在０．３％Ｏ２的低氧条件下贮藏２４ｄ果实的风味仍正常。     

六种藓类植物茎的比较解剖学研究

通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.     

Cause of Senescence of Nine Sorts of Flowers

The levels of endogenous phytohormones and respiratory rate in nine sorts of flowers such as Cymbidium faberi Rolfe, Nopalxochia ackermannii Kunth and others were investigated both at full bloom and senescence and meanwhile the effect of exogenous phytohormones on prolonging the blossoms and promoting ethylene production were tested. There is a high content of endogenous ethylene in all the long-lived flowere, about 3–16 folds higer than the short-lived ones. There is a high level of ABA at full blooming flowers of short-lived flowers, in which there is no or only some cytokinins in it, but the ratio of CTK (6BA+zeatin)/ABA is smaller(l.7). The endogenous ABA reached a much higher level at senescence in all nine sorts of flowers, so it is reasonable to consider that it is ABA which plays an important role of regulation in controlling flower's senescence. There is a much higher level of GA3 and zeatin in the long-lived flowers which is not demonstrated in the shortlived ones. The respiratory rate is one of the factors controtling the longevity of flowers, but it does not play a decided role. Application of 6BA and zeatin prolongs distinctly orchid’s longevity, however exogenous IAA through the promotive action on ethylene production, evidently extends the longevity of the flowers of the Nopalxochia ackermannii Kunth.     

龙胆科药用植物化学成分的研究现状

龙胆科植物在我国的分布范围很广,且多数为药用植物,其多数种属的药用植物,至今其化学成分尚未被系统研究。综述了目前龙胆科药用植物的化学成分的研究现状及一般提取方法,对近年来发现的环烯醚萜及裂环烯醚萜类化合物进行了总结,为本科药用植物的更深入研究提供了参考。     

The effects of glutamine of the maintenance of embryogenic cultures of Cryptomeria japonica

Summary Embryogenic tissues of sugi (Cryptomeria japonica) were induced on a modified Campbell and Durzan (CD) medium containing 1 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 600 mg l⁻¹ glutamine, and subcultured in the medium of the same composition for over 1 yr. This resulted in a mixed culture of embryogenic and non-embryogenic cells. When embryogenic cells were isolated and cultured independently, their capacity to form embryogenic aggregates was lost. Thus, the non-embryogenic cells present within a mixed culture system were essential to the formation of embryogenic aggregates. When embryogenic tissues were isolated and cultured independently on a high glutamine-containing (2400 mg l⁻¹) medium, dry weights and endogenous levels of glutamine increased, and the tissue could generate a large number of embryogenic aggregates. Amino acid analysis of embryogenic and non-embryogenic cells from the maintenance culture indicated a higher level of glutamine was present in the latter. The high endogenous level of glutamine in the non-embryogenic portion of mixed cell masses may be the supplier of glutamine for maintaining the embryogenic property of the tissues.     

Specificity of action of piperidylcholine derivatives as substrates of cholinesterases of various origin

The review deals with study of enzymologic properties of a novel highly specific acetylcholinesterase substrate, N-(β-acetoxyethyl) piperidinium iodomethylate (“piperidylcholine”), and its 30 derivatives that were tested as effectors of cholinesterases of mammals and various species of Pacific squids. It was proven for the first time that responsible for specificity of action was structure of cyclic ammonium grouping of the alcohol part of molecule of the ester substrate. Analysis of specificity is performed based on enzymatic hydrolysis parameters—activity of catalytic center of cholinesterases and bimolecular constant of the reaction rate that are determined at optimal and low substrate concentrations. Among the specially synthesized group of thioester compounds there is revealed one more highly specific acetylcholinesterase substrate—N-(β-acetoxyethyl) piperidinium.     

真菌类遗传学分析的知识结构教学

本文以认知结构理论为指导,讨论了真菌类遗传分析与高等动植物遗传分析的内在联系,认为利用这种内在联系进行教学可收到好的效果并说明了作者的具体教学过程。 Abstract:In the paper, the relationship between genetic analysis of Fungi and genetic analysis of high animal and plant was discussed.A good results were obtained when we adopted this method in the teaching.     

医疗机构合理用药评价模型的构建研究

目的 针对医疗机构的合理用药水平进行评价研究。方法 根据医疗机构合理用药的具体要求,构建医疗机构合理用药评价指标体系,采用基于模糊群决策的方法和多指标评价分析法构建医疗机构合理用药评价模型。结果 构建了基于模糊群决策的医疗机构合理用药评价模型,并通过实例分析证明了评价模型的可行性。结论 建立的基于模糊群决策的医疗机构合理用药评价模型能够对医疗机构的合理用药水平进行科学评价,为提高医疗机构合理用药水平奠定基础。     

The mechanism of hatching of eggs of Haemonchus contortus

Fluid collected from hatching eggs of Haemonchus contortus contained a lipase which hydrolysed 2-naphthyl laurate (about 0·7 μmol naphthol freed /h/10⁶ eggs). The fluid also hydrolysed l-leucinamide (about 2·3 μmol leucine freed/h/10⁶ eggs). The fluid when added to normal or heated eggs caused ‘hatching’. ‘Hatching’ also occurred in exsheathing fluid from infective juveniles and in a preparation of pancreatic lipase containing leucine aminopeptidase. A purified mammalian leucine aminopeptidase in combination with several different lipases did not attack egg shells.The ‘spontaneous’ hatching of eggs of H. contortus was strongly inhibited by 1,10-phenanthroline, 10^?3M, and this inhibition was reversed by Zn²⁺. However, the inhibition of ‘hatching’ of eggs in externally applied hatching fluid, or the hydrolysis of leucinamide in hatching fluid was generally less marked.