高山植物花形态特征对花温度积累的影响

高山生态系统的低温环境不利于植物繁殖器官的发育和传粉过程,因此能改善花内或花序温度的结构对植物繁殖具有积极意义。该研究利用红外测温仪测量了高寒草甸中64种植物的花温度和叶温度以计算花温度积累,并检测了系统发育、花大小、花对称方式和花大小对花温度积累的影响。结果表明:所测量的64种植物种类,花部温度均高于叶部温度。花温度积累的系统发育信号较弱,表明物种间花温度积累的差异可能主要与不同物种对温度的需求有关。花温度积累与花大小存在显著的正相关关系,且两侧对称花的温度积累比辐射对称花更为迅速,但花对称方式和花颜色对花温度积累并没有显著的影响。该研究结果表明花温度积累在不同植物间存在很大的差异,但这些差异对植物繁殖的实际贡献和意义仍需要进一步验证。     

植物花发育的分子机理研究进展

花的发育分为开花决定、花的发端和花器官的发育三个阶段。植物开花由多条途径诱导,包括光周期和光质诱导、春化作用、自主途径、赤霉素诱导、碳水化合物诱导等;植物体本身也存在着开花抑制途径。各种开花诱导途径能激活花分生组织特性基因,使茎端分生组织转变为花分生组织。花器官的发育由器官特性基因决定,这些基因的精确表达需要花分生组织特性基因的激活和多个正、负调节因子的调控;另有一类基因控制着花发育的对称性。花发育机理的研究具有重要的理论意义和广泛的应用前景。     

五福花科花部形态的变异式样及其系统学意义

由于四福花Ｔｅｔｒａｄｏｘａ顶花、侧花均为典型的４数花,并被认为是科内最原始的属,因而长期以来关于五福花Ａｄｏｘａ“总苞一萼”还是“萼一花冠”的争议得到了彻底解决。根据本研究,五福花顶花和侧花的变异痃较五福花科另外３个分类群要高得多。五福花顶花和侧花的变异率分别为２０％和３６１％。通过后位雄蕊的退化和两则相邻花瓣的融合,雄蕊和花瓣从６数至３数的减少系列仅存在于五福花中。本文假设五福花科顶花和侧花的     

植物成花分子机理研究的进展

植物在成花诱导结束后,转变为花分生组织,而后分化产生花器官。文中着重介绍了花器官形成分化ABC模型及基因调控的分子机理。     

中国叉柱花属(爵床科)二新记录种————中越叉柱花、密花叉柱花

确定爵床科Acanthaceae叉柱花属Staurogyne的中越叉柱花S. petelotii Benoist和密花叉柱花S. vicina Benoist为中国新记录。     

藏药椭圆叶花锚中抗肝炎有效成分的含量测定

运用RP-HPLC建立了花锚中青兰苷、去甲氧基花锚苷和花锚苷的含量分析方法,为栽培花锚替代野生花锚入药提供一定的科学依据。花锚苷、去甲氧基花锚苷和青兰苷分别在0．68～3．40μg(r=0．9998)、0．36～1．80μg(r=0．9990)和0．80～4．00μg(r=0．9979)有良好线性关系,平均回收率分别为100．39％(RSD=2．60％)、99．79％(RSD=3．55％)和100．71％(RSD=2．19％)。栽培花锚中花锚苷和去甲氧基花锚苷的含量(抗肝炎活性成分)和在野生花锚中的含量相比无明显差别,可以初步证明栽培花锚可以替代野生花锚入药。     

中国囊萼花属一新记录种——茎花囊萼花

首次报道了囊萼花属(Cyrtandromoea Zoll.)的1个中国新记录种——茎花囊萼花(Cyrtandromoea grandis Ridl.),该种原记载产于泰国、马来半岛和苏门答腊岛,2019年在中国云南省勐海县布朗山地区发现有分布。茎花囊萼花与囊萼花(Cyrtandromoea grandiflora C.B.Clarke)最为相似,但前者聚伞花序生于老茎上,每一花序3～18朵花,二者容易区别。     

黄瓜花原基的形成及与Ca~(2+)的关系

以黄瓜为试验材料研究了肉眼可见的花原基突起之前 ,花原基早期的分化过程。结果显示花原基分化和开花的起始节位是第一真叶节 ;肉眼可见花原基突起前早期的分化是在叶腋亚表皮部位形成一个球形的花原基起始细胞团 ,此细胞团进一步分裂、扩大形成肉眼可见的花原基突起 ;第一真叶节的花原基起始细胞团分化集中发生于 6～ 7d苗龄时期 ;Ca2 + 在花原基起始细胞团细胞中主要分布在细胞壁和细胞间隙 ,而在非起始细胞团的叶腋亚表皮细胞则主要分布在液泡中 ,并对Ca2 + 在花原基起始细胞团分化中的作用进行了讨论。     

辽宁省花蝇属一新种（双翅目：花蝇科）

本文记述采自辽宁省西部山区花蝇科花蝇属Ａｎｔｈｏｍｙｉａ Ｍｅｉｇｅｎ,１８０３１新种,中华花蝇,新种Ａｎｔｈｏｍｙｉａ ｓｉｎｅｎｓｉｓ ｓｐ．ｎｏｖ。     

植物花发育的分子机理研究进展

花的发育分为开花决定、花的发端和花器官的发育三个阶段。植物开花由多条途径诱导,包括光周期和光质诱导、春化作用、自主途径、赤霉素诱导、碳水化合物诱导等;植物体本身也存在着开花抑制途径。各种开花诱导途径能激活花分生组织特性基因,使茎端分生组织转变为花分生组织。花器官的发育由器官特性基因决定,这些基因的精确表达需要花分生组织特性基因的激活和多个正、负调节因子的调控;另有一类基因控制着花发育的对称性。花发育机理的研究具有重要的理论意义和广泛的应用前景。     

光照对蕨类植物配子体假根向重力性的影响

对８种蕨类植物配子体假根向重力性反应的研究结果表明,除卷柏Ｓｅｌａｇｉｎｅｌｌａ ｔａｍａｒｉｓｃｉｎａ Ｓｐｒｉｎｇ配子体假根无向重力性反应并且其生长方向与光照方向无关外,其它７种的配子体假根均有向重力性反应,并且假根的向重力性反应在配子体发育初期,因光照的方向不同而异,表现为负向光性。随着配子体发育至片状体阶段,光对其向重力性反应的影响逐渐减弱,而重力的影响增强。在蕨类植物配子体发育初期,光对     

中国鳐类脑颅的研究

作者解剖观察了33种,隶于4目、7亚目、15科、19属的中国鳐类脑颅的形态。研究结果认为:锯鳐目和鳐目是原始类群,它们均具吻软骨,其中圆犂头鳐科和团扇鳐科是特化类群。电鳐目亦具吻软骨,它们是特化和退化类群。在较高等的鲼目则无吻软骨。依据鳐类不同的分类阶元,其脑颅亦各具有不同的式型。     

THE RATE OF DECLINE OF MILK SECRETION WITH THE ADVANCE OF THE PERIOD OF LACTATION

It is shown that the course of decline of milk secretion with the advance of the period of lactation may be expressed by the equation of a monomolecular chemical reaction; that is, the percentage decline of milk secretion with the advance of the stage of lactation is constant. This substantiates the idea that milk secretion is limited by a chemical reaction, and, in general, brings lactation into the class of processes the speed of which is determined by the concentration of a limiting substance.     

蜀龙头骨及脑颅的解剖

本文对蜥脚类蜀龙(Shunosaurus)的脑颅分别从其头骨特征、脑垂体、耳区、视觉系统、脑神经等诸方面进行了较为详细的解剖研究,结果表明 Shunosaurus 内颈动脉不分叉;基蝶骨突强烈收缩;外淋巴囊出现在中耳及 IX、X、XI 孔与颈静脉孔内分外合等现象十分独特.因此,Shunosaurus 应视为一种特化的原始蜥脚类.     

STABILITY OF SUSPENSIONS OF SOLID PARTICLES OF PROTEINS AND PROTECTIVE ACTION OF COLLOIDS

1. It is shown that the concentrations of different salts required to precipitate suspensions of gelatin-coated collodion particles in water are practically identical with the concentrations of the same salts required for the "salting out" of gelatin from aqueous solutions. Neither effect shows any relation to the electrical double layers surrounding the particles. 2. It is shown that at the isoelectric point of gelatin, suspensions of gelatin-coated collodion particles are not stable and it had been shown previously that gelatin is least soluble at the isoelectric point. The addition of salt increases both the solubility of gelatin in water as well as the stability of suspensions of gelatin-coated collodion particles in water, and both effects increase with the valency of one of the ions of the salt. 3. This latter effect is not due to any charges conferred on the gelatin particles by the salts, since the cataphoretic experiments show that salts like NaCl, Na₂SO₄, or CaCl₂, which at the isoelectric point of gelatin increase the solubility of gelatin as well as the stability of suspensions of gelatin-coated collodion particles, leave the particles practically uncharged in the concentrations in which the salts are efficient. 4. It follows from all these facts that the stability of suspensions of gelatin-coated particles in water depends on the solubility of gelatin in water; e.g., on the chemical affinity of certain groups of the gelatin molecule for water. 5. Though crystalline egg albumin is highly soluble in water, the stability of collodion particles coated with crystalline egg albumin does not depend upon the affinity of the albumin molecule for water, but depends practically alone on the electrical double layer surrounding each particle. As soon as the P.D. of this double layer falls below 13 millivolts, the suspension is no longer stable. 6. The critical potential for the stability of suspensions of collodion particles coated with genuine egg albumin is the same as that for particles of boiled (denatured) white of egg. Since through the process of heating, egg albumin loses its solubility in water, it is inferred that egg albumin undergoes the same change when it forms a film around a solid particle like collodion. 7. The influence of electrolytes on the stability of suspensions of collodion particles coated with casein or edestin was similar to that of collodion particles coated with egg albumin. The experiments are, however, complicated by the fact that near the isoelectric point CaCl₂ and even NaCl cause a suspension again at concentrations of about M/2 or 1 M, while still higher concentrations may cause a precipitation again. These latter effects have no connection with double layers, but belong probably in the category of solubility phenomena. 8. These experiments permit us to define more definitely the conditions for a general protective action of colloids. Protective colloids must be capable of forming a durable film on the surface of the suspended particles and the molecules constituting the film must have a higher attraction for the molecules of the solvent than for each other; in other words, they must possess true solubility. Only in this case can they prevent the precipitating action of low concentrations of electrolytes on particles which are kept in suspension solely by the high potentials of an electrical double layer. Thus gelatin films, in which the attraction of the molecules for water is preserved, have a general protective action, while crystalline egg albumin, casein, and edestin, which seem to lose their attraction for water when forming a film, have a protective action only under limited conditions stated in the paper.     

猕猴桃嫁接试验

本文报道猕猴桃不同嫁接时期、嫁接方法和不同分类群的砧木试验结果,猕猴桃最适宜的嫁接时期是落叶后至翌年萌芽前,嫁接方法以切接为好,嫁接成活率均在90％以上。同种和同一分类群的砧穗间有良好的亲和力,嫁接均有较高的成活率。不同分类群间嫁接效果较差,如中华猕猴桃桂海4号嫁接于中华猕猴桃砧木上的成活率,生长情况均比嫁接其它分类群为砧的有显著差异。     

重楼属两种植物种子及其附属结构的发育

重楼属两种植物(五指莲Paris axialis和滇重楼Paris polyphylla var.yunnanensis)种子发育的过程基本一致。双受精发生于授粉后10—15天。胚乳为沼生目型。种子发育延续的时间约为150—170天。胚胎发育终止于球形或稍有分化的阶段。种子具二层种皮。 二种重楼种子成熟时的外部形态显著不同。五指莲Paris axialis的种子呈浅棕黄色,长椭圆形,部分为绿白色海绵质假种皮所包裹。假种皮由珠柄发育而来,呈楔形。滇重楼Parispolyphylla var.yunnanensis的种子鲜红色,不规则圆形,外种皮肉质多浆。无假种皮。珠柄橙黄色,短而纤细。     

合浦珠母贝珍珠的生物学性能初步检测

本研究报道了合浦珠母贝珍珠的生物学性能初步检测结果。珍珠作为—种天然的生物材料。在医药、化妆品工业等领域中的应用已很广泛。本研究对合浦珠母贝珍珠进行了体外细胞毒性试验、溶血试验和经静脉全身急性毒性试验的研究。实验结果表明,合浦珠母贝珍珠具有较好的细胞相容性,其浸提液对实验动物无明显毒性。在本研究中,合浦珠母贝珍珠的浸提液对兔血红细胞的溶血指数高于对照组。     

不同年龄蝾螈肢体再生速度的比较

1.根据外形与组织学的观察,比较了不同年龄的东方蝾螈(Cynops orientalis)肢体的再生速度。我们发现再生速度随年龄增加而降低。幼虫的再生速度最高,变态以后再生速度显著地下降,但幼体(一岁、尚未达性成熟)仍比成体(性成熟)快得多。2.幼虫肢体再生之一切组织学过程均比变态后的动物进行快。幼体和成体的前二再生时期(组织去分化期和再生芽基形成期)进行速度相差不大,它们之间的差别主要在于分化期中再生体之生长和分化速度。3.再生初期速度(即组织去分化速度)依赖于断切时肢体组织的分化程度。变态前后组织分化程度的巨大差异造成了幼虫和幼体、成体之间组织去分速度的巨大差别。幼虫肢体组织分化程度低,去分化比变态后进行快得多;幼体和成体肢体所有组织的分化均接近或已达到完成,形态上彼此没有显著差异,这可能解释为什么它们的去分速度都减慢而且彼此大约相等。4.实验期中幼体体长仍继续增加,而成体生长几已陷于停顿,这可能是它们的再生体生长速度的差别的原因。此外,也应考虑到性成熟过程中组织生理的变化可能对再生体的生长和分化发生影响。5.我们讨论了内分泌和再生的关系并认为变态和性成熟过程中内分泌变化所引起的组织生理和组织分化程度的差...     

THE EFFECT OF GESTATION ON THE RATE OF DECLINE OF MILK SECRETION WITH THE ADVANCE OF THE PERIOD OF LACTATION

1. Data are presented showing that the course of decline of milk secretion with the advance of the period of lactation in farrow cows follows the course of decline of a monomolecular chemical reaction, that is each month''s milk production is a constant percentage of the production of the preceding month (94.77 per cent in the case of the cow under consideration), from which it is inferred that milk secretion is limited by a chemical reaction initiated at parturition, and declining with the decrease of the concentration of the limiting substance as it is transformed into milk. 2. Data are presented showing that the decline in milk secretion due to pregnancy is related to the increase in weight of gestating animals, from which it is inferred that growth of the fetus is in part, at least, responsible for the decline in the milk flow due to the demand of the fetus for nutrients to support its life processes.