植酸对稻米品质影响的研究（Ⅰ）

本文报道在水稻生长的抽穗期、齐穗期、灌浆期和蜡熟期喷施不同浓度植酸改良稻米品质的研究。结果表明,在水稻生长的不同阶段,控制喷施植酸浓度可提高糙米率,降低稻米垩白。     

中国蚌螨属1新种及1新纪录种记述（蜱螨亚纲：水螨群：蚌螨科）

记述采自江西的蚌螨属1新种,定名为丰城蚌螨Unionicola(Parasitatax)fengchengensis sp.nov.和1个中国新纪录种。     

双功能抗体介导的胃癌杀伤效应

将诱变的αＣＤ３杂交瘤（ＴＫ~－）与ＰＤ４杂交瘤（ＨＧＰＲＴ~－）融合,获得分泌双功能抗体（ＢｓＡｂ）的四体杂交瘤Ｃ３．ＢｓＡｂＣ３可分别与ＣＤ３分子及胃癌相关抗原Ｐ４０反应．体外杀伤试验证实,当效靶比为４０：１,ＢｓＡｂＣ３浓度为１ｍｇ／Ｌ时,其杀伤效应可达７７．６％．该杀伤效应具有明显的特异性,仅Ｐ４０阳性表达的靶细胞可被溶解,体内杀伤试验证实,裸鼠接种胃癌细胞后５ｄ,以ＢｓＡｂＣ３活化的外周血淋巴细胞（ＰＢＬｓ）经局部皮下注射处理,可使移植胃癌完全消退（５／５）．这一明显的治疗作用可能与局部注射途径有关,可供临床应用参考．     

稻茎毛眼水蝇幼虫田间分布型及抽样技术

根据14丘稻田稻茎毛眼水蝇幼虫调查资料．对其幼虫分布型进行了分析。结果表明;用I、CAm／m、Iσ四种聚集指标法测定,64．3％的田块呈随机分布．28．4%为均匀分布．7．3%为聚集分布。用Iwao平均拥挤度和Taylor幂法则测定．其田间分布型符合随机分布。用频次拟合法测验,50%的田块同时符合渡松、奈曼和负二项分布三种分布型;35．7%的田块同时符合2种分布型。根据该虫田间分布型的特点．制定了相应的序贯抽样技术。     

长果秤锤树保护现状的初步研究

本文从自然环境、种群分布、数量、种群结构、人为破坏、保护及管理等方面分析了湖南石门长果秤锤树的就地保护现状,并从种子繁殖、扦插繁殖、栽培、试管保存及开发利用潜力等方面总结了武汉植物所近年来对长果秤锤树进行迁地保护研究的初步成果,并提出了相应的保护措施。     

乳链菌肽的分离纯化和部分生物学性质

用乳酸链球菌ＳＭ５２６进行乳链菌肽的发酵生产,产量为４０～５０ｍｇ／ｌ．经中空纤维超滤器超滤,非极性大孔吸附树脂ＸＡＤ－２层析,ＣＭ－ＳｅｐｈａｄｅｘＣ－２５层析和ＳｅｐｈａｄｅｘＧ－５０层析纯化了该肽。ＳＤＳ－ＰＡＧＥ表明达均一,ＲＰ－ＨＰＬＣ表明其纯度不低于９５％。ＳＤＳ－ＰＡＧＥ测其Ｍｒ约为３６００,用ＩＥＦ测其等电点为９．５．酸性条件下稳定且抗热;对胰蛋白酶、胃蛋白酶和木瓜蛋白酶不敏感,但对α－胰凝乳酶和蛋白酶Ｋ敏感。乳链菌肽对多种革兰氏阳性菌有强烈的抑制作用;以枯草杆菌和金黄色葡萄球菌为指示菌,其作用方式是杀菌。     

Multiplicity of brain cysteine sulfinic acid decarboxylase — Purification,characterization and subunit structure

Cysteine sulfinic acid decarboxylase (CSAD), the rate-limiting enzyme in taurine biosynthesis, appears to be present in the brain in multiple isoforms. Two distinct forms of CSAD, referred to as CSAD I and CSAD II, were obtained on Sephadex G-100 column. CSAD I and CSAD II differ in (1) the elution profile on Sephadex G-100 column; (2) the sensitivity towards Mn²⁺, methione, and other sulfur-containing amino acids and (3) their immunologic properties. CSAD II has been purified to about 2,500-fold by a combination of column chromatographies and polyacrylamide gel electrophoresis (PAGE). The purity of the enzyme preparation was established as judged from the following observations: (1) a single protein band was observed under various electrophoretic conditions, e.g., 5–20% nondenaturing PAGE, 7% nondenaturing PAGE and 10% SDS-PAGE and (2) in nondenaturing PAGE, the protein band comigrated with CSAD activity. CSAD II has a molecular weight of 90 kDa and is a homodimer consisting of two 43 ± 2 kDa subunits. CSAD appears to require Mn²⁺ for its maximum activity. Other divalent cations fail to replace Mn²⁺ in activation of CSAD activity. However, the precise role of Mn²⁺ in the action of CSAD remains to be determined.     

Cloning, Expression, and Affinity Purification of RecombinantShigella flexneriInvasion Plasmid Antigens IpaB and IpaC

Shigella flexneriand related enteropathogenic bacteria are important agents of bacillary dysentery, a potentially life-threatening illness for children in underdeveloped regions of the world. Onset of shigellosis stems fromS. flexneriinvasion of colonic epithelial cells, leading to localized cell death and inflammation. Invasion plasmid antigens (Ipa) B, C, and D are three secreted proteins encoded by the large virulence plasmid ofS. flexnerithat have been implicated as essential effectors of this cell invasion process. These proteins are expressed as part of theipaoperon and are among the major targets of the host immune response to shigellosis. Biochemical characterization of the Ipa invasins has been complicated by the fact they have not been purified in the quantities needed for detailedin vitroanalysis. Here we describe the first cloning, expression, and extensive purification of IpaB and IpaC fusion proteins fromEscherichia colifor use in dissecting of the protein biochemistry ofS. flexneripathogenesis. A variety of approaches were used to prepare significant quantities of these proteins in their soluble forms, including the use of different host cell lines, modification of bacterial growth conditions, and the use of alternative plasmid expression vectors. Now that these Ipa proteins are available in a highly pure form, it will be possible to initiate studies on their important biological and immunological properties as well as their recruitment into high-molecular-weight protein complexes. Together with IpaD (purified as part of a previous study), these purified proteins will be useful for: (a) exploring properties of the host immune response toS. flexneriinvasion, (b) elucidating the specific biochemical properties that lead to pathogen internalization, (c) analyzing the importance of specific Ipa protein complexes in host cell invasion, and (d) monitoring, or perhaps even augmenting, the efficacy of live oral vaccines in human trials.     

Isolation and characterization of two cDNAs from atlantic cod encoding two distinct psychrophilic elastases

The cDNAs encoding two different Atlantic cod elastases have been isolated and sequenced. The predicted amino acid sequences revealed two preproelastases, consisting of a signal peptide, an activation peptide and a mature enzyme of 242 and 239 amino acids. Amino acid sequence identity between the two cod elastases was 60.1% and identity with mammalian elastases ranged from 50–64%. The two cod elastases contain all the major structural features common to serine proteases, such as the catalytic triad His57, Asp102 and Ser195. Both cod elastases have a high content of methionine, consistent with previous findings in psychrophilic fish enzymes.     

Synaptic effects induced in efferent neurons of the parietal associative cortex of the cat by stimulation of the cerebellar nuclei

Properties of EPSP, evoked in efferent neurons of the parietal associative cortex by stimulation of the cerebellar nuclei, were studied in acute experiments on anesthetized and immobilized cats; intracellular recording was used. The neurons were identified by their antidromic activation after stimulation of the motor cortex, pontinen.n. proprii, or red nucleus. The effects of stimulation of the cerebellar nuclei were of oligo- and polysynaptic nature. The latencies of cerebellofugal EPSP correlated with the latencies of antidromic activation, and correlations were significant both in the cases when the effects of stimulation of separate efferent projections (cortico-cortical, cortico-pontine, or cortico-rubral) and the effects of stimulation of separate cerebellar nuclei were analyzed. The functional role of the efferent systems of the parietal associative cortex and significance of functional parameters of the neurons constituting these systems are discussed.Neirofiziologiya/Neurophysiology, Vol. 27, No. 3, pp. 190–198, May–June, 1995.