安顺市林木种质资源区系研究

本研究基于野外调查和文献资料整理，摸清了安顺市林木种质资源本底，并对其植物区系特征进行了分析。结果表明：安顺市林木种质资源丰富，共有140科507属1 652种，包括蕨类植物1科1属1种，裸子植物10科22属43种，被子植物129科484属1 608种。优势科属明显，兼有较多的单型科和单型属，其中，优势科40科301属1231种，优势属127属1 070种；单型科6科6属6种，单型属27属27种，体现出安顺市植物区系的古老性质。从区系来看，热带分布72科263属，占总科、属数的57.14%、60.18%，温带分布34科153属，占总科、属数的26.98%、35.01%，该地区热带性质科属明显多于温带性质科属，同时兼有一定的温带特征，呈现出由热带向温带过渡的亚热带植物区系性质。     

秦岭地区苔类植物区系的初步研究

在野外调查和已有资料的基础上,分析了秦岭地区苔类植物区系组成和分布类型.现知秦岭地区苔类、角苔类有35科66属270种.其中指叶苔科、叶苔科、裂叶苔科、合叶苔科、齿萼苔科、羽苔科、光萼苔科、耳叶苔科、细鳞苔科、瘤冠苔科为优势科;指叶苔属、鞭苔属、叶苔属、裂叶苔属、合叶苔属、羽苔属、扁萼苔属、光萼苔属、耳叶苔属、细鳞苔属为优势属.在区系成分上,温带成分最高,东亚、热带亚洲成分次之,中国特有成分也比较高.同时有大量的科中仅一属和属中仅一种的类群存在,说明本地区苔类植物科属结构比较简单,分化程度不高.还分析了秦岭苔类植物区系及我国其他5个地区苔类植物区系之间的关系.     

福建茫荡山黄枝润楠群落植物区系特点研究

采用典型调查与线路调查相结合的方法,对茫荡山自然保护区黄枝润楠群落的植物区系进行调查分析.结果表明,该群落植物种类丰富,区域性单种科和少种科、单种属和少种属、少属科和寡属科占优势;以樟科、山茶科、茜草科、蔷薇科、紫金牛科、桑科等为优势科;以润楠属、山茶属、冬青属、榕属等为优势属,以樟科、山茶科、桑科、紫金牛科、五加科、冬青科等为表征科.体现了该区系组成分散,优势科属明显,区系起源古老,具有华南植物区系的特征.     

山西庞泉沟国家自然保护区种子植物区系研究

庞泉沟自然保护区共有种子植物89科359属809种,其中裸子植物2科6属7种,被子植物87科353属802种。含5属以上的科15科,单、寡种属共330属,这些科、属在植物区系组成中具有重要作用。种子植物科、属、种的区系地理成分复杂多样。科的分布区类型中,世界分布型40科,北温带分布型24科,分别占总科数的44.94%和26.97%。属的分布区类型中,温带成分256属,占总属数的82.05%,反映出该区植物区系的温带性质。种的分布区类型中,中国特有分布种居首位,尤以华北成分占优势,其中华北落叶松、黄刺玫、油松等为该区植被建群种或优势种。科、属、种的特有现象不平衡,没有中国特有科,中国特有属、特有种分别为7属、325种。     

兔子的名片

兔子,俗称兔类,为兔形目兔科动物的通称。兔形目共有2科：兔科和鼠兔科。兔科动物现存9属共50种左右。其中兔属最大,有20多种,林兔属有12种,岩兔属4种,其余6属（山兔属、粗毛兔属、苏门兔属、穴兔属、琉球兔属、火山兔属）各有1种。     

广西花坪国家级自然保护区种子植物区系

广西花坪国家级自然保护区有野生种子植物163科583属1295种,其中裸子植物5科7属10种,被子植物158科576属1285种。本区种子植物区系的地理成分复杂,联系广泛。163科可分为9个分布类型及10个分布变型,其中热带分布科89科,占总科数的66 %;583属可分为13个分布类型及16个分布变型,热带性质属285属、温带性质属235属,两者基本达到平衡。本区系具有古老、孑遗和原始性;少种科、属数量多;特有现象明显,东亚特有科4科,中国特有科1科,中国特有属23属。种子植物区系具有亚热带性质。     

琅琊山蝶类资源调查初报

在安徽省滁州市琅琊山国家级森林公园采集到凤蝶科蝴蝶５属１０种、蛱蝶科１２属１７种、粉蝶科３属５种、眼蝶科３属４种、灰蝶科１０属１２种、喙蝶科１属１种、弄蝶科３属４种。其中,１种为我国特有珍稀蝶类,３１种为安徽省新记录,并记录各种蝴蝶的学名,寄主和区系组成。     

陕西延安北洛河流域蝶类资源调查及区系研究

通过对延安北洛河流域的蝶类资源进行调查,发现该地区共有蝴蝶6科54属75种(凤蝶科2属3种、粉蝶科7属10种、眼蝶科10属13种、蛱蝶科15属25种、灰蝶科11属15种、弄蝶科8属9种),其中34种为单属种,陕西省新纪录5种;区系结构分析表明该地区蝴蝶以古北种为主。标本保存于延安大学生命科学学院标本馆。     

浙江省凤阳山自然保护区蕨类植物区系的研究

经野外调查和资料整理已知凤阳山自然保护区共有蕨类植物37科74属196种和7变种.主要科为鳞毛蕨科、水龙骨科、金星蕨科、蹄盖蕨科、铁角蕨科、卷柏科、膜蕨科,主要属为鳞毛蕨属、铁角蕨属、卷柏属、复叶耳蕨属、瘤足蕨属、凤尾蕨属、瓦苇属.分布区类型以世界分布和泛热带分布科、泛热带分布属、东亚分布种为主,表现出亚热带向暖温带过渡的特点.与邻近6山蕨类植物区系相似性系数的比较表明,与凤阳山蕨类植物区系亲缘关系最近的是浙江九龙山.凤阳山共有57种中国特有蕨类,有较高的保护价值.     

西双版纳片断热带雨林蝶类群落结构与多样性研究

对西双版纳片断热带雨林蝴蝶群落结构和多样性进行了研究。样地内共收集蝴蝶9 204号,隶属于10科,62属,84种。主要成分是：粉蝶科(粉蝶属、迁粉蝶属)、凤蝶科 (凤蝶属、麝凤蝶属)、蛱蝶科(斐豹蛱蝶属、尾蛱蝶属),眼蝶科(幕眼蝶属、矍眼蝶屑)等属的种类。属、种以风蝶科最丰富;个体数量以粉蝶科最多;喙蝶科的属、种和个体数量最少。各样地的多样性指数、均匀度和种类丰富度是：热带原始雨林自然保护区>城子片断热带雨林>植物园片断热带雨林>曼峨片断热带雨林。     

How are tRNAs and mRNA arranged in the ribosome? An attempt to correlate the stereochemistry of the tRNA-mRNA interaction with constraints imposed by the ribosomal topography.

Two tRNA molecules at the ribosomal A- and P-sites, with a relatively small angle between the planes of the L-shaped molecules, can be arranged in two mutually exclusive orientations. In one (the 'R'-configuration), the T-loop of the A-site tRNA faces the D-loop of the P-site tRNA, whereas in the other (the 'S'-configuration) the D-loop of the A-site tRNA faces the T-loop of the P-site tRNA. A number of stereochemical arguments, based on the crystal structure of 'free' tRNA, favour the R-configuration. In the ribosome, the CCA-ends of the tRNA molecules are 'fixed' at the base of the central protuberance (the peptidyl transferase centre) of the 50S subunit, and the anticodon loops lie in the neck region (the decoding site) of the 30S subunit. The translocation step is essentially a rotational movement of the tRNA from the A- to the P-site, and there is convincing evidence that the A-site must be located nearest to the L7/L12 protuberance of the 50S subunit. The mRNA in the two codon-anticodon duplexes lies on the 'inside' of the 'elbows' of the tRNA molecules (in both the S-type and R-type configurations), and runs up between the two molecules from the A- to the P-site in the 3' to 5'-direction. These considerations have the consequence that in the S-configuration the mRNA in the codon-anticodon duplexes is directed towards the 50S subunit, whereas in the R-configuration it is directed towards the 30S subunit. The results of site-directed cross-linking experiments, in particular cross-links to mRNA at positions within or very close to the codons interacting with A- or P-site tRNA, favour the latter situation. This conclusion is in direct contradiction to other current models for the arrangement of mRNA and tRNA on the ribosome.     

Effects of the Activity of the Internal Globus Pallidus-Pedunculopontine Loop on the Transmission of the Subthalamic Nucleus-External Globus Pallidus-Pacemaker Oscillatory Activities to the Cortex

Resting tremor is the most specific sign for idiopathic Parkinson' disease. It has been proposed that parkinsonian tremor results from the activity of the central oscillators. One of the hypotheses, which have been proposed about the possible principles underlying such central oscillations, is the subthalamic nucleus (STN)-external globus pallidus (GPe)-pacemaker hypothesis. Activity from the central oscillator is proposed to be transmitted via trans-cortical pathways to the periphery. A computational model of the basal ganglia (BG) is proposed for simulating the effects of the internal globus pallidus (GPi)-pedunculopontine (PPN) loop activity on the transmission of the STN-GPe-pacemaker oscillatory activities to the cortex, based on known anatomy and physiology of the BG. According to the result of the simulation, the GPi-PPN loop activity can suppress the transmission of the STN-GPe-pacemaker oscillatory activities to the cortex. This suppressive effect is controlled by various factors such as the strength of the synaptic connection from the PPN to the GPi, the strength of the synaptic connection from the GPi to the PPN, the spontaneous tonic activities of the GPi and PPN, the direct excitatory projections from the STN to the PPN, the frequency of the STN oscillatory burst activity, the duration of the STN burst, and the maximum T-type calcium channel conductance in the type-I PPN neurons.     

四膜虫S1有性生殖的电镜观察Ⅱ.接合区的形态与配子核的交换

四膜虫接合膜上的小孔是两接合体细胞质相连的通道。配子核形成后,按合膜由于增生而出现装有细胞器等的囊状折叠,并可脱离下来而落入另一细胞中,这可能是胞质交流的又一途径。配子核的交换不是从膜上原有小孔通过的,而是在溶酶体等作用下、使膜破裂,由核后方的微管推动进入对侧细胞中。 本文记述了四膜虫S1有性生殖过程中接合区的形态和配子核的交换。     

State of the hypothalamo-hypophyseal neurosecretory system of rabbits in anaphylactic shock]

With the aid of morphometric and histochemical methods a study was made of the hypothalamo-hypophyseal neurosecretory system of rabbits in anaphylactic shock. The following occurred in rabbits which survived the shock: an enlargement of the perikarions and reduction in the size of the nuclei and nucleoli of the neurosecretory cells; the content of the neurosecretory substance was increased in the whole neurosecretory system. In rabbits which perished from shock the nuclei and the nucleoli of the neurosecretory cells diminished to a lesser extent, perikarion measurements remained unchanged and the content of the neurosecretory substance in the posterior lobe of the hypophysis fell. Thus, in the animals which survived the shock the processes of synthesis of the neurohormones by the neurosecretory cells were sharply activated, but the secretion of the neurohormones from the posterior lobe of the hypophysis was inhibited; in animals which perished from shock the activation of the hormone formation in the neurosecretory cells was less pronounced, but the processes of the secretion of the neurohormones from the posterior lobe were apparently intensified.     

保护区周边居民薪柴采集对乔木分布的影响——以四川王朗大熊猫自然保护区为例

保护区内周边地区的自然村庄中人们的日常生活对于村庄附近的森林群落结构有着重要的影响。通过分析乔木蓄积量和“乔木-灌木”复合系统中乔木的相对密度随着距离村落中心远近变化的函数关系,揭示当地居民薪柴采集活动对于乔木分布影响的规律。首先对于四川省平武县木座乡、木皮乡和白马乡里10个村庄进行随机入户农村家庭经济调查,掌握基本经济条件;然后对于调查结果进行聚类分析,选定小河、厄里和详述加3个典型村庄作为研究对象。按照距村落中心距离远近作梯度样带调查,计算出各个样带中的木材蓄积量和“乔木一灌木”复合系统中乔木的相对密度,利用数理统计方法进行模型拟合。拟合结果显示：（1）贫富差距对于乔木分布规律没有明显的影响,3个村落的数据分析结果类似。说明这3个村落的贫富差距还没有足以影响村落周围乔木分布。（2）木材蓄积量和“乔木．灌木”复合系统中乔木的相对密度与距村落中心位置距离的函数关系分别符合Logistic模型和Growth模型。在距离小于第1域值（3,4km）的时候,因变量随着自变量——距离的增加而缓慢增加。这说明这一区域内乔木分布受到薪柴采集活动影响很大,虽然也有所增加但是趋势不明显。当距离在第1域值（3～4km）至第2域值（7—8km）的时候,曲线切线斜率突然增大。这说明薪柴采集活动频率和强度迅速增加,因而导致乔木的蓄积量和密度都快速恢复。当距离继续增大的时候,因变量增长速率又逐渐回落,乔木分布也已经与原始林中的状态相似。     

New findings concerning the spread of natural foci of infection in the transpolar region of eastern Siberia]

New materials are presented on the presence of the foci of anthropozoonozes in the Extreme North. For the first time there was established the existence in the subarctic tundra of the Taimyr peninsula of the arbovirus foci of the tick-borne encephalitis complex. A virus of the tick-borne encephalitis complex was isolated in 1973 from the gamasida ticks Haemogamasus ambulans Thorel. and Hirstionyssus isabellinus Oudms. and the nests of the Siberian lemming Lemmus lemmus L. This pointed to the existence in the Transpolar region of the foci or arboviruses in the nest-hole biocenoses of the lemmings outside the bird colonies. Cultures of tularemia bacilli (which proved the etiology of the epizootic among the lemmings observed in 1973 and also the presence of the lemming natural foci of tularemia and their combination with the arbovirus foci) were isolated from the lemmings at the same territory. The results of serological examination of the local population and of the animals pointed to the circulation in the Transpolar region of the causative agents of leptospirosis, toxoplasmosis, Q-fever and of the Asian tick-borne rickettsiosis.     

Mechanism of the electric response of lipid bilayers to bitter substances.

In order to clarify by what mechanism the lipid bilayer membrane changes its potential under the stimulation of bitter substances, a microscopic model for the effects of the substances on the membrane is presented and studied theoretically. It is assumed that the substances are adsorbed on the membrane and change the partition coefficients of ions between the membrane and the stimulation solution, the dipole orientation in the polar head, and the diffusion constants of ions in the membrane. It is shown, based on the comparison of the calculated results with the experimental ones, that the response arises mainly from a change in the partition coefficients. Protons play an essential role in the membrane potential variation due to the change in their partition coefficients. The present model reproduces the following observed unique properties in the response of lipid bilayers to bitter substances, which cannot be accounted for by the usual channel model for the membrane potential: 1) the response of the membrane potential appears even under the condition that there is no ion gradient across the membrane, 2) the response remains even when the salt in the stimulating solution is replaced with the salt made of an impermeable cation, and 3) the direction of the polarization of the potential is not reversed, even when the ion gradient across the bilayer is reversed.     

Prediction of the loading along the leg during snow skiing.

The complete force and moment of each cross section of the leg between the ski boot top and the knee during normal skiing were predicted from measurements of the force and moment under the toe and heel of the boot and the flexion of the ankle. The force and moment components predicted at the base of the boot were significantly different from those predicted at sites of potential injury at the boot top and the knee. The maximum torsional and maximum varus-valgus moments predicted at the knee over all subjects tested were 70 Nm and 149 Nm, which are within the estimated range of the ultimate strength of the knee without support from contracted muscles crossing the knee. Regression analyses were used to find the force components at the base of the boot that best predict the bending and torsional moments at the boot top and knee. The torsional moments at the boot top and knee are best predicted by the medial-lateral force at the toe. The varus-valgus moment at the boot top and knee are best predicted by the resultant medial-lateral force component at the base of the boot. The set of best predictors of the anterior-posterior bending moments at the boot top and knee includes the vertical force at the toe, the vertical force at the heel and the component of the total vertical force directed perpendicular to the leg.     

L’industrie en calcaire du site Paléolithique d’Isernia la Pineta : un modèle interprétatif de stratégie comportementale

The studies and the researches carried out in the last years on the Palaeolithic site of Isernia La Pineta have brought to consider in new way the activities realized by the human group that lived the basin of Isernia during the Middle Pleistocene offering an important key of interpretation of the behavioural strategies of the prehistoric man. The analysis of the exploitation of the raw material has confirmed the presence on the site of two different lithotypes: flint and limestone; the lithological dichotomy is related to the functional dichotomy of the raw material that seems to have conditioned the activities of the human group in different areas of the site. The necessity to deepen the study on the limestone has derived from the evidence brought to light in the last excavation campaigns of a remarkable concentration of the flaked limestone pebbles and the flake scars in some areas of the explored archeosurfaces, particularly on the 3a and on the overlooking layers. The present study has the purpose to explain the characteristics of the limestone finds both in reference to the raw material and to its state of preservation both to the technotypological evidences and its spatial distribution with the purpose to better understand the modalities of the exploitation of the raw material. The information collected until today have permitted to obtain a precise knowledge of the environmental context and the territorial resources exploited by the human group showing an opportunistic capability to find the most advantageous behavioural solution for the necessities of subsistence.     

Behavior of the cell center during epithelial cell spreading

In the epithelial cells of mouse embryo renal channels, centrioles are located near the plasma membrane of the apical part of the cell. In most of the cells an active centriole carries a cilium, which comes out into the channel lumen. In the epithelial cells, suspended after trypsinisation and in single cells adhering to the substrate, the centrioles are located near the nucleus, and the outcoming cilia are not observed. In the spread cells of epithelial islets, the centrioles are also found near the nucleus, and in most cases an active centriole carries a cilium, which comes out of the cytoplasm at the upper side of the cell. In the peripheral cells of the islet, centrioles are positioned between the nucleus and the active edge of the cell. In the epithelial cells in situ, a relatively small number of microtubules radiate from the active centrioles. In the suspended cells, the activation of microtubule formation is observed in the cell center. In the spread cells of the epithelial islets there occurs a further increase in the number of microtubules radiating from the active centrioles. In the peripheral cells which cause translocation of the epithelial islet in the culture, the number of microtubules, radiating from the centrioles does not differ significantly from that of the inner cells of the islet. The cell center of the epithelial cells does not seem to be actively involved in the locomotion of the epithelial cells in the culture.