担子菌不亲和性因子特性的研究概况

对不亲和性因子的交配特性 ,不亲和性因子的构成 ,不亲和性因子的复等位基因现象等的研究进展进行了综述 ,并提出了不亲和性因子的研究前景     

基于S- 核酸酶的自交不亲和性的分子机制

自交不亲和性是一种广泛存在于显花植物中的种内生殖障碍, 可以抑制近亲繁殖而促进异交。其中, 以茄科、玄参科和蔷薇科为代表的配子体自交不亲和性是最常见的类型。这类自交不亲和性是由单一的多态性S-位点所控制。目前的研究发现这一位点至少包含两个自交不亲和反应特异性决定因子: 花柱中的S-核酸酶和花粉中的SLF(S-Locus F-box)蛋白。该文将主要介绍并讨论基于S-核酸酶的自交不亲和性分子机制的研究进展。     

基于S-核酸酶的自交不亲和性的分子机制

自交不亲和性是一种广泛存在于显花植物中的种内生殖障碍,可以抑制近亲繁殖而促进异交。其中,以茄科、玄参科和蔷薇科为代表的配子体自交不亲和性是最常见的类型。这类自交不亲和性是由单一的多态性S-位点所控制。目前的研究发现这一位点至少包含两个自交不亲和反应特异性决定因子：花柱中的S-核酸酶和花粉中的SLF（S-Locus F-box）蛋白。该文将主要介绍并讨论基于S-核酸酶的自交不亲和性分子机制的研究进展。     

哺乳动物卵母细胞不对称分裂的研究进展

哺乳动物卵母细胞成熟过程需要进行两次连续的不对称分裂,最终形成体积差异巨大的子细胞：大体积的卵母细胞和两种体积较小的极体。不对称分裂现象是哺乳动物卵母细胞减数分裂的典型特征,不对称分裂后的卵母细胞是高度极化的细胞。精卵结合后,细胞重新恢复了对称分裂,但是在卵母细胞减数分裂过程中形成的极性特征却得以保留并影响早期胚胎的极性。本文对近年来在哺乳动物卵母细胞不对称分裂方面的相关研究展开综述,从细胞质不对称分裂和细胞核不对称分裂两个方面对染色体、细胞骨架在哺乳动物卵母细胞不对称分裂中的作用、细胞器在哺乳动物卵母细胞成熟过程中的重组分配、染色体非随机分离等过程进行介绍,旨在从细胞和分子水平阐述哺乳动物卵母细胞不对称分裂的主要机制。     

婴幼儿腹泻与乳糖不耐受关系的研究

目的研究婴幼儿腹泻乳糖不耐受的发生率;轮状病毒肠炎与乳糖不耐受的的关系;婴幼儿腹泻去乳糖饮食的疗效。方法采用醋酸铅法检测粪便乳糖的含量。应用ELISA双抗体夹心法测定粪便轮状病毒抗原抗。分组观察婴幼儿腹泻去乳糖饮食的疗效。结果婴幼儿腹泻乳糖不耐受的发生率为62.5%。其中<1岁乳糖不耐受的发生率为70.59%;>1岁乳糖不耐受的发生率为42.86%,0.010.05。婴幼儿腹泻乳糖不耐受去乳糖饮食有效率93.33%;对照组有效率53.33%,P<0.01。结论(1)婴幼儿腹泻时乳糖不耐受发生率高达62.5%;(2)RV肠炎时可合并继发性乳糖不耐受,继发性乳糖不耐受可能加重腹泻症状,是使腹泻时间延长的重要原因;(3)婴幼儿腹泻时乳糖不耐受给去乳糖饮食疗效肯定。     

乳糖酶治疗小儿腹泻病的临床分析

目的 研究小儿腹泻病继发乳糖不耐受的年龄、病因及乳糖酶治疗继发乳糖不耐受的效果.方法 对382例腹泻继发乳糖不耐受患儿进行年龄、病因分析,同时将患儿分成治疗及对照两组,分析乳糖酶的疗效.结果 小儿腹泻继发乳糖不耐受以婴幼儿多见,轮状病毒感染是继发乳糖不耐受的主要病因,乳糖酶治疗继发乳糖不耐受疗效显著.结论 婴幼儿腹泻常规给予乳糖酶可以缩短病程,减少治疗费用,患儿及家长易于接受.     

萝卜自交不亲和基因SLG6的CAPS标记的开发

萝卜是我国的主要蔬菜之一,其杂种优势十分明显,培育自交不亲和系是萝卜杂种优势育种的主要途径之一.本研究根据萝卜自交不亲和基因SLG6序列设计特异引物,以8个自交系为材料,其中自交不亲和系和自交亲和系各4个,扩增SLG6基因第232～711bp之间的单拷贝片段,8个材料均获得了一条480bp的特异片段.用限制性内切酶TaqⅠ对该片段进行酶切,自交不亲和系均产生约125bp和244bp的片段,其中,244bp的片段为自交不亲和系所特有,可作为SLG6基因的CAPS标记用于萝卜自交不亲和基因SLG6的检测;而自交亲和系则具有与自交不亲和系相同的125bp的片段和不同的多态性片段.     

来自太空的召唤

没有找到存在的证据，不等于找到了不存在的证据。近些年来，地球生命生存环境极限的拓展、大量地外水存在证据以及太阳系外大量行星系统的发现，都使人类相信生命不应该是地球这颗行星上的偶然神秘事件，我们也许有很多文明的邻居。     

浅析临床输血不规范行为的对策及方法

目的:总结分析出临床输血中不规范的行为,并提出有效的解决对策与方法,从而降低临床输血安全隐患风险。方法:随机抽取我院100份输血病历,查看其护理输血病程及记录,统计分析出临床输血不规范行为。结果:经过统计分析,我院临床护理人员存在查对制度执行不严、血液在室温放置时间过久、不重视输血过程前15分钟观察、不正确的血液加温方法、不正确的加压输血等不规范的输液行为。结论:在临床输血过程中依然存在大量不规范行为,只有对不规范行为进行改正,才能避免临床输血安全隐患,保障患者生命安全,提高护理质量,减少医患纠纷,构建和谐的医患关系。     

HPLC同步测定多种合成色素含量检测结果的不确定度评定

目的：分析高效液相色谱法（HPLC）同步测定多种色素含量的不确定度。方法：通过评定各不确定度分量,计算合成标准不确定度及扩展不确定度。结果：HPLC同步测定多种色素含量的扩展不确定度范围在3.97%~7.13% （k=2）;天平称量和提取回收率对合成色素的测量结果不确定度影响最大。结论：本研究建立了简便易行的HPLC同步测定肉制品中色素含量检测结果的不确定度评定方法。     

THE POWER OF THE " A" -" NOT A" METHOD

The " A" - " Not A" method is a rating method with two categories. It is often treated as a discrimination method. Unlike forced choice procedures, the Thurstonian model for this method involves a choice criterion. In statistical tests, it is treated as a comparison of two proportions. In this paper, the power for hypothesis tests involving the monadic and replicated monadic " A" - " Not A" method is discussed. The power functions and the sample sizes needed for 80% power are given based on Thurstone's δ. Designs with equal and unequal allocations for A and A (Not A) samples are considered. The power of the method is also compared with that of four forced choice methods under the assumption that the perceptual variance is identical among methods. The comparison shows that, in general, the power for the five methods ranks from high to low: the 3-AFC, 2-AFC, " A" - " Not A", triangular and duo-trio. The comparison also shows that, based on the same number of panelists and/or the same sample size for the A and A⁻ samples for the methods, if the panelists are not too discrepant and the choice criterion in the " A" - " Not A" method is not too strict or too lax, the power of the " A" - " Not A" method is very close to that of the 2-AFC method.     

THE EFFECT OF A PARTIAL BARRIER ON THE MOVEMENT OF A HYBRID ZONE

Computer simulations of clines (Brues, 1972; Endler, 1977) as well as theoretical arguments (Nagylaki, 1975), have shown that steps in gene frequencies will be pulled to partial barriers (areas of reduced gene flow) if they form within approximately a cline width of the partial barrier. The behavior of a hybrid zone between two chromosomal taxa (“Moreton” and “Torresian”) of the acridine grasshopper Caledia captiva in southeast Queensland has been analyzed and found to comform qualitatively with a model of altered gene flow patterns. Clines in four enzyme systems were analyzed for 1983 and 1986 along a transect across the hybrid zone. The clines have shifted towards an area of regenerating forest, while homozygote frequencies have increased at this point. This forest barrier has broken the continuity of the spatial distribution of C. captiva, forming population islands in part of the hybrid zone, and thus reducing the amount of gene flow. The distance between the barrier and the original cline is approximately of the order of a cline width, so that they would be expected to interact. Historical information suggests that the secondary contact between the “Moreton” and “Torresian” taxa occurred very recently (1844–1940), due to the intensive land-clearing activities during the European settlement.     

禄丰大猿化石分类的修订

本文将禄丰西瓦古猿与巴基斯坦和土耳其的标本进行了对比,认为前者与后者有明显的不同。提出把禄丰的标本修订为禄丰古猿属同名种(Lufengpithecus lufengensis)。     

A STUDY ON THE ESTRADIOL-INDUCED AUGMENTATION OF A SPECIFIC CELL PRODUCT IN THE VAGINAL EPITHELIUM OF THE NEONATAL MOUSE

The epithelial content of an estradiol-sensitive immunological marker (CVA) has been quantified by mixed haemagglutination on tissue sections from the vagina of neonatal mice exposed to different schedules of estradiol treatment.
Daily administration of estradiol-17β (5 μg/day) was especially efficient in elevating the CVA content when the hormone was administered during the first four days after birth.
Following a single injection of estradiol-17β (5 μg in aqueous suspension) on one of the first five days of life, the vaginal epithelium reacted with a more vigourous CVA accumulation when challenged with estradiol at a later time. The effect was most pronounced for days 2 and 3. The possibility that this early effect of estradiol may involve other mechanisms than those operative in the estradiol action at later stages, is discussed.     

A FIBER APPARATUS IN THE NUCLEUS OF THE YEAST CELL

The structure and mode of division of the nucleus of budding yeast cells have been studied by phase-contrast microscopy during life and by ordinary microscopy after Helly fixation. The components of the nucleus were differentially stained by the Feulgen procedure, with Giemsa solution after hydrolysis, and with iron alum haematoxylin. New information was obtained in cells fixed in Helly's by directly staining them with 0.005% acid fuchsin in 1% acetic acid in water. Electron micrographs have been made of sections of cells that were first fixed with 3% glutaraldehyde, then divested of their walls with snail juice, and postfixed with osmium tetroxide. Light and electron microscopy have given concordant information about the organization of the yeast nucleus. A peripheral segment of the nucleus is occupied by relatively dense matter (the "peripheral cluster" of Mundkur) which is Feulgen negative. The greater part of the nucleus is filled with fine-grained Feulgen-positive matter of low density in which chromosomes could not be identified. Chromosomes become visible in this region under the light microscope at meiosis. In the chromatin lies a short fiber with strong affinity for acid fuchsin. The nucleus divides by elongation and constriction, and during this process the fiber becomes long and thin. Electron microscopy has resolved it into a bundle of dark-edged 150 to 180 A filaments which extends between "centriolar plaques" that are attached to the nuclear envelope.     

A DISCUSSION AND PROPOSAL CONCERNING THE USE OF THE TERM CALCISPHERES

Abstract:  The terminology and grouping of spherical, calcareous microfossils of unknown biological affinity, usually referred to as calcispheres, are diffuse. The term calcispheres is inconsistently used, the morphological and taxonomical concepts are mostly ill-defined and a formal definition is lacking. To resolve this issue, we propose, in analogy with the erection of the Acritarcha for organic microfossils of unknown origin, a new group called Calcitarcha, including all calcareous microfossils with a central cavity for which the biological affinities remain unknown.     

A THEORY ON THE EVOLUTION OF THE EXINE IN ORCHIDACEAE

The development of secondarily derived features in orchid pollen precludes the possibility of applying evolutionary trends hypothesized for dicot pollen to orchid pollen and perhaps even monocot pollen. There are three lines of pollen wall development, all secondarily derived from a possible tectate-perforate ancestral type, i.e., tectate-imperforate with incipient columellae (Cypripedioideae), intectate lacking a foot layer (Orchidoideae), and tectate-imperforate with globular masses of sporopollenin (Vandoid Epidendroideae).     

THE DEVELOPMENT OF A COMPARATIVE METHOD FOR THE EVALUATION OF THE MOTH-PROOFNESS OF WOOL SERGE

Existing test methods for the moth-proofness of wool were compared in inter-laboratory experiments and found to be lacking in accuracy and agreement between laboratories.
Several factors influencing the usefulness of such a test method were investigated, and it was found that a considerable gain in accuracy could be reached if weight loss due to larval attack on test samples was referred to weight loss obtained with a standard wool serge impregnated with a standard moth-proofing substance. Apart from this principle, improvements in the general testing procedure, including the number of test samples and test animals used, the definition of weight loss and the introduction of strict randomization procedures proved to be valuable.
As a provisional reference standard, wool serge impregnated with dinitro-α-naphthol was adopted. A tolerance level for the moth-proofness of wool serge was laid down.     

几种不同条件下竹红菌甲素的光谱特性

本文报道了不同浓度竹红菌甲素的吸收光谱.甲素在不同比例的二甲基亚砜与HEPES溶液中的荧光光谱,试验了甲素与几种生物物质的结合,说明脂溶性的甲素能与类脂很好的结合,甲素光照后对红细胞膜的损伤大于白蛋白和色氨酸,说明生物膜是甲素光敏作用较好的靶.