硒拮抗氟对肾脏损害的酶组织化学观察

本实验以酶组织化学方法（ＳＤＨ、ＬＤＨ、ＡＣＰ、ＡＬＰ）探讨硒对氟引起肾脏损害的拮抗作用。大鼠分为六组,Ａ组常规饮水;Ｂ组饮水含亚硒酸钠２ｍｇ／Ｌ;Ｃ组饮水中含氟化钠１５０ｍｇ／Ｌ;Ｄ、Ｅ、Ｆ组饮水中分别含氟化钠１５０ｍｇ／Ｌ,依次含亚硒酸钠０．５ｍｇ／Ｌ、２ｍｇ／Ｌ、４ｍｇ／Ｌ。８周后断头处死,观察肾脏组织中ＳＤＨ、ＬＤＨ、ＡＣＰ、ＡＬＰ的活性。结果表明,与Ａ组相比,Ｃ组近曲小管ＳＤＨ、ＡＬＰ活性减弱,ＬＤＨ、ＡＣＰ活性明显增加;Ｂ组ＳＤＨ、ＡＣＰ活性正常,基底膜清晰;Ｄ、Ｅ、Ｆ组均能提高ＳＤＨ活性,其中Ｅ组较稳定;Ｆ组ＡＣＰ活性较高。结果说明了氟引起肾近曲小管溶酶体的破坏,而硒（２ｍｇ／Ｌ）能稳定溶酶体膜,拮抗氟对肾脏的损害作用     

重组人EPO真核表达质粒在大鼠骨骼肌中的表达及其对贫血的治疗作用

目的和方法构建ＥＰＯ真核细胞表达载体（ｐｃＤ２ＥＰＯ）,用缝线法和注射法将其直接导入肾性贫血大鼠股四头肌,观察ＥＰＯ在骨骼肌细胞中的表达及其对贫血的治疗作用。结果：ｐｃＤ２ＥＰＯ导入股四头肌２周后,骨骼肌细胞内出现ＥＰＯｍＲＮＡ,提示被导入的ＥＰＯ基因在肌细胞内得到表达。贫血动物被治疗１周后,缝线组和注射组动物的ＨＧＢ和ＲＢＣ均显著升高;在第３周,缝线组的ＨＧＢ和ＲＢＣ接近健康大鼠的水平;至第４周,两个治疗组的ＨＧＢ和ＲＢＣ仍显著高于对照组。结论：经缝线法导入的ｐｃＤ２ＥＰＯ在骨骼肌中的表达效率及对贫血的治疗效果明显高于直接注射法,而两种治疗方法对改善肾性贫血动物肾脏清除ＢＵＮ的功能无明显差异     

紫外线B对水稻叶组织中活性氧代谢及膜系统的影响

增强ＵＶ－Ｂ处理下,水稻叶片的Ｏ净产生速率、Ｈ２Ｏ２和ＭＤＡ含量以及膜透性都显著增加,敏感性弱的品种Ｏ２净产生速率和膜伤害程度较低。在ＵＶ－Ｂ处理初期活性氧清除系统的水平增高,但随着处理时间的延长,ＳＯＤ、ＣＡＴ和ＡＰ活性以及ＡＳＡ含量降低,其中ＡＰ和ＳＯＤ活性的下降最为明显,而敏感性弱的品种ＳＯＤ活性始终高于敏感性强的品种。处理１４ｄ后去掉ＵＶ－Ｂ,再经则１４ｄ上述各指标均恢复到与对照相近的水平。根据这些结果推测,水稻的ＵＶ－Ｂ伤害可能主要是由于ＳＯＤ活性的降低而导致Ｏ增生和膜脂过氧化。     

黄瓜子房（幼果）中内源激素含量和过氧化物酶活性变化及其单 …

授粉与不授粉的黄爪单性结果品系ＥＰ－６以及授粉的间意志生结果品系ＹＤ－１、ＺＱ－１均能正常结果,不授粉的ＹＤ－１、ＺＱ－１果产不能发育或发育成畸形。从花前２ｄ至开花当天,ＥＰ－６子房中ＩＡＡ、ＡＢＡ含量与过氧化物酶（ＰＯＤ）活性均高于ＹＤ－１、ＺＱ－１。从开花当天至花后４ｄ的幼果,４个能单性结果的ＩＡＡ、ＡＢＡ含量均上升而ＰＯＤ活性下降,不授粉ＹＤ－１、ＺＱ－１的ＩＡＡ、ＡＢＡ含量花后仍维持低水平     

丙型肝炎病毒E2基因DNA免疫实验动物研究

将编码丙型肝炎病毒（ＨＣＶ）Ｅ２蛋白４１７～７５０位氨基酸的ＤＮＡ片段　克隆到真核表达载体ｐｃＤＮＡ　３．１（－）中的ＣＭＶ　ＩＥ启动子下游,构建成ＨＣＶ　Ｅ２重组真核表达质粒　ｐｃＥ２。ＥＬＩＳＡ法检测ｐｃＥ２　ＤＮＡ免疫兔血清中的Ｅ２抗体变化和维持规律,结果显示免疫２０ｄ已有　抗体产生,３０ｄ后开始进入高峰,４０ｄ时达到最高值,至第９０ｄ抗体水平保持平稳,抗体滴度　达到１∶１６００左右。流式细胞计数仪（ＦＡＣＳ）检测ｐｃＥ２　ＤＮＡ免疫鼠ＣＤ４＋、ＣＤ８＋Ｔ淋巴细胞变　化情况,与注射空载体ｐＣＤＮＡ３．１（－）的阴性鼠相比,ＣＤ４＋淋巴细胞水平略有上升,ＣＤ８＋　细胞水平有较大升高,增幅达３５．４６％。免疫组化检测结果显示注射ｐｃＥ２的小鼠组织中有明显　的阳性着色,而注射ｐｃＤＮＡ３．１（－）的对照组小鼠免疫组化结果为阴性。以上结果表明：ｐｃＥ２　在实验动物内表达出的ＨＣＶ　Ｅ２蛋白可以引起免疫动物的体液免疫应答和细胞免疫应答,尤其　是ＭＨＣ－１限制性杀伤性ＣＤ８＋Ｔ淋巴细胞水平的提高对清除　病毒是十分有利的,因此ＨＣＶ　Ｅ２　ＤＮＡ免疫有可能成为预防和治疗ＨＣＶ感染的一条新途径。     

P物质对GABAA和GABAB受体介导的DRG神经元膜反应的调制作用

实验在幼年大鼠ＤＲＧ标本上进行。应用细胞内记录观察了ＳＰ对ＧＡＢＡ反应的调制作用。结果证明：（１）单独滴加ＳＰ（５×１０（－６）－４×１０（－５）ｍｏｌ／Ｌ）或浴槽灌流ＳＰ（１０（－６）－５×１０（－６）ｍｏｌ／Ｌ）不引起膜电位的改变或仅有轻微的去极化,但却能使ＧＡＢＡ引起的去极化反应减小５０．８±２０．２％（±ＳＤ）（２０／３０）;（２）单独滴加ＳＰ可使多数受检细胞ＡＰＤ５０延长２８．７±９．１％（±ＳＤ）（１０／１８）;（３）在预加ＳＰ后,能使ｂａｃｌｏｆｅｎ所引起的ＡＰＤ５０缩短效应（２０．６±２．９％,±ＳＤ）完全消除（４／１２）或翻转成ＡＰＤ（５０）延长１９．３±８．９％（±ＳＤ）（８／１２）;（４）预加ＧＡＢＡＢ受体激动剂ｂａｃｌｏｆｅｎ（１０（－４）－１０（－３）ｍｏｌ／Ｌ）３０—９０ｓ后明显地抑制ｍｕｓｃｉｍｏｌ（１０－４－１０－３ｍｏｌ／Ｌ）引起的去极化反应,其抑制效应达５４．４±１８．８％（±ＳＤ）（１７／２０）。由于ＤＲＧ神经元的胞体通常可用来作为研究初级传入终末的模型,因而本文实验结果提示：介导伤害性刺激信息的Ｐ物质在背角的释放,可能作用于初级传入终末,从而产生对抗ＧＡＢＡ介导的突触     

精氨酸加压素对大鼠抗体产生和淋巴细胞增殖的上调作用

大鼠侧脑室注射１００ｎｇ精氨酸加压素（ＡＶＰ）,用ＥＬＩＳＡ法检测血中对鸡卵白 白抗原产生的ＩｇＧ抗体水平。结果显示,ＩｇＧ水平高于对照,而ＡＶＰ的Ｖ１受体阻断剂ＤＰＡＶＰ则可阻断此作用;ｉｃｖ８００ｎｇＡＶＰ,大鼠的ＳＲＢＣ溶血素 水平高于对照;ｉｃｖ１００ｎｇ、８００ｎｇＡＶＰ２ｈ后,脾淋巴细胞对ＭＴＴ产生的颜色反应均比对照增加,而ＤＰＡＶＰ可阻断之;ｉｃｖ８００ＡＶＰ２ｈ后,脾淋巴细胞对ＭＴ     

荔枝和龙眼种子发育过程中ABA含量及对源ABA敏感性的变化

在荔枝和龙眼种子发育过程中,内源ＡＢＡ水平先是上升,至大约７８－８０ＤＰＡ时出现高峰,之后两者ＡＢＡ含量均不断下降。果实成熟时采收的种子,ＡＢＡ含量比高峰时分别下降近６倍。另外,随着种子的发育,种子及其胚轴对外源ＡＢＡ的敏感性亦持续下降,１０＾－４ｍｏｌ／ＬＡＢＡ可以完全抑制９０ＤＰＡ前的荔枝和龙眼种子的萌发,但对成熟种子１０＾－２ｍｏｌ／ＬＡＢＡ亦不能抑制萌发。龙眼种子离体胚轴的ＳＡＢＡ高于荔枝     

传染性法氏囊病病毒VP3结构蛋白基因在大肠杆菌中的高效表达

传染性法氏囊病病毒（ＩＢＤＶ）是危害养鸡业的重要病原之一,属双股双节段ＲＮＡ病毒科成员,由Ａ和Ｂ两个片段的ｄｓＲＮＡ构成,大小分别约３３００－３４００ｂｐ和２８００－２９００ｂｐ。基因片段Ａ首先编码ＶＰ２－ＶＰ４－ＶＰ３聚合蛋白,然后再断裂成ＶＰ３、...     

维生素A缺乏胎鼠作为先天性心脏病动物模型的实验研究

目的　探讨将维生素Ａ缺乏（ＶＡＤ）胎鼠作为先天性心脏病动物模型的可行性。方法取１１－１９ｄ不同胎龄正常及ＶＡＤ胎鼠心脏经石蜡包埋、切片及 ＨＥ染色观察其发育情况。结果 １．实验组饲料含维生素Ａ（ＶＡ）７μｇ／１００ｇ,经ＶＡＤ饮食喂养后实验组大鼠血清ＶＡ水平明显低于对照组［（０．１６８±０．０５９）μｍｏｌ／Ｌ Ｖｓ（２．１８±０．２３）μｍｏｌ／Ｌ,ｔ＝３２．８８, Ｐ＜０．００１］。 ２．大鼠死亡百分比：饲养于屏障系统的ＶＡＤ大鼠死亡百分比较饲养于开放系统中的要低４．６倍（１０％ Ｖｓ ４５．８３％．ｘ ２＝１６．６４, Ｐ＜０．００１）,对照组为０。 ３．实验组大鼠受孕百分比及每只孕鼠产仔数均低于对照组［５８．３３％ Ｖｓ ８１．５％, ｘ ２＝４．３７,Ｐ＜０．０５：（６．９７±２．７９） Ｖｓ（１３ ±１．０５）,ｔ＝７．１６, Ｐ＜０．００１］。 ４．经切片观察１１～１５ ｄ胎龄胎鼠实验组心脏出现明显发育延迟的占３６．６７％, １６～１９ ｄ胎龄胎鼠实验组心脏畸形占４１．４３％,血管异常占１８．５７％。结论ＶＡＤ胎鼠可用来作为先天性心脏病动物模型,但需改进饲养环境以减少异常死亡。     

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.     

Photoregulation of seed germination of wild-type and of an aurea-mutant of tomato

Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m⁻² s⁻¹. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to P_fr.     

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。     

Interconnection of parameters of regulation system of lipid peroxidation and of morphophysiological parameters of mouse liver

A complex analysis of seasonal fluctuations of the mean group parameters of the system of regulation of lipid peroxidation has been performed in liver of Balb/c mice. Association of lipid characteristics and morphophysiological parameters is studied in the Balb/c mouse liver. An inter-connection is revealed between the liver index and the amount of lysoforms of phospholipids, the scale and character of the interconnection differing essentially depending on proportion of phos-phatidylcholine in mouse liver phospholipids.     

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.     

Physiological characteristics of various species of strains of carboxydobacteria

Seven strains of aerobic carbon monoxide-oxidizing bacteria (carboxydebacteria) when growing on CO as sole source of carbon and energy had doubling times which ranged from 12–42 h. The activity profiles obtained after discontinuous sucrose density gradient centrifugation indicated that the CO-oxidizing enzymes are soluble and the hydrogenases are membrane-bound in all strains examined. The CO-oxidizing enzymes of Pseudomonas carboxydohydrogena, Pseudomonas carboxydoflava, Comamonas compransoris, and the so far unidentified strains OM2, OM3, and OM4 had a molecular weight of 230,000; that of Achromobacter carboxydus amounted to 170,000. The molecular weights of the CO-oxidizing and H₂-oxidizing enzymes turned out to be identical. The cell sonicates were shown to catalyze the oxidation of both CO and H₂ with methylene blue, thionine, phenazine methosulfate, toluylene blue, dichlorophenolindophenol, cytochrome c or ferricyanide as electron acceptors. Methyl viologen, benzyl viologen, FAD⁺, FMN⁺, and NAD(P)⁺ were not reduced. The spectrum of electron acceptors was identical for all strains tested. Neither free formate, hydrogen nor oxygen gas were involved in the CO-oxidation reaction. Methylene blue was reduced by CO at a 1:1 molar ratio. The results indicate that CO-oxidation by carboxydobacteria is catalyzed by identical or similar enzymes and that the reaction obeys the equation CO+H₂OCO₂+2H⁺+2e^- as previously shown for Pseudomonas carboxydovorans.Dedicated to Otto Kandler remembering almost three decades of enjoyable cooperation     

Modulation of allostery of pyruvate kinase by shifting of an ensemble of microstates

Since the introduction of the concepts of allostery about four decades ago, much advancement has been made in elucidating the structure-function correlation in allostery. However, there are still a number of issues that remain unresolved. In this review we used mammalian pyruvate kinase (PK) as a model system to understand the role of protein dynamics in modulating cooperativity. PK has a triosephosphate isomerase (TIM)(α/β)₈ barrel structural motif. PK is an ideal system to address basic questions regarding regulatory mechanisms about this common (α/β)₈ structural motif. The simplest model accounting for all of the solution thermodynamic and kinetic data on ligand-enzyme interactions involves two conformational states, inactive E^T and active E^R. These conformational states are represented by domain movements. Further studies provide the first evidence for a differential effect of ligand binding on the dynamics of the structural elements, not major secondary structural changes. These data are consistent with our model that allosteric regulation of PK is the consequence of perturbation of the distribution of an ensemble of states in which the inactive E^T and active E^R represent the two extreme end states. Sequence differences and ligands can modulate the distribution of states leading to alterations of functions. The future work includes: defining the network of functionally connected residues; elucidating the chemical principles governing the sequence differences which affect functions; and probing the nature of mutations on the stability of the secondary structural elements, which in turn modulate allostery.