学前教育专业《人体解剖生理学》教学改革探索

文章分析了学前教育专业《人体解剖生理学》教学中存在的问题,提出人体解剖生理学教学改革对策.笔者结合多年的教学实践,根据学前教育专业学科特点,主要采用课件教学实施教学过程,取得较好教学效果.     

Soil properties and herbaceous characteristics in an age sequence of Haloxylon ammodendron plantations in an oasis-desert ecotone of northwestern China

Haloxylon ammodendron,a typical desert shrub with C4 pathway of photosynthesis,possessing a strong ability to adapt to an extreme drought environment,has a rapid growth rate in sandy lands and is widely used in sand-fixing shelter-forest systems in oasis-desert ecotones.To assess the effects of H.ammodendron plantation on the soil,we measured soil properties and herbaceous characteristics along a nearly 40-year chronosequence after H.ammodendron was planted in shifting sand dunes in an oasis-desert ecotone.Results showed that silt and clay fractions increased significantly in the topsoil.The accumulation rates of soil organic carbon(SOC),total nitrogen(TN) and total phosphorus(TP) were faster in the early stages(0–9 years) and slower in the late stages(9–39 years).The soil p H and electrical conductivity(EC) were higher than those in the non-vegetation dunes.Moreover,the soil properties in the topsoil(0–5 cm) showed larger variation scope than those in the deeper soil layers(5–20 cm).The significant relationships of the soil silt+clay content with the chemical properties mainly appeared in the topsoil.The wind erosion susceptibility of the soil,evaluated by erodible fraction(EF),decreased significantly with increasing H.ammodendron plantation age.Additionally,the annual pioneer herb,Agriophyllum squarrosum,was gradually substituted by the annual salt-tolerant herb,Bassia dasyphylla,with increasing plantation age.These results showed beneficial effects of H.ammodendron plantation on improving soil conditions.However,the dynamics of the herbaceous species also reminded us that the longterm effects of H.ammodendron plantation,especially on changes in vegetation composition,still need further evaluation.     

黄河鲤肾脏的显微和亚显微结构观察

应用常规解剖学和组织学方法在光镜和电镜下观察成体黄河鲤肾脏的显微和亚显微结构.试验结果显示,黄河鲤的肾脏包括头肾和中肾两部分.头肾实质中没有肾单位,主要由造血组织和淋巴组织构成,可观察到黑色素巨噬细胞中心和甲状腺滤泡;中肾实质中包含有肾小体、肾小管和拟淋巴组织,肾小体由鲍曼氏囊和与其相接触的血管球组成.肾小管由颈段、第...     

不同光照条件对大花萱草叶片解剖结构的影响

对黄色、金黄色和红色3个品系大花萱草进行不同的光照处理,对其叶片解剖结构进行分析研究.结果表明:不同光强对3种大花萱草叶片上、下表皮的厚度影响均不显著,叶片上、下表皮的细胞大小及叶主脉导管直径在不同处理下不存在显著差异;气孔密度的排序为T1＞T2＞T3,净光合速率可能与气孔密度呈正相关,气孔指数随光强的减弱而降低.大花萱草叶片解剖结构受不同光照条件的影响较小.     

Influence of the pore structure of wood on moisture desorption at high relative humidities

Abstract

The influence of the porous structure on moisture desorption of two temperate and five tropical hardwoods was studied. Two experimental techniques were used to perform moisture desorption tests from full saturation at 25°C. The first one was the saturated salt solutions [between 33% and 90% relative humidity (RH)] and the second one was the pressure membrane method (above 96% RH). More emphasis was given to results obtained at high RH, given that sorption in that case is mainly governed by the capillary forces. The porous structure of these hardwoods was characterized by mercury intrusion porosimetry (MIP) and by quantitative anatomical analysis. The results showed that desorption of liquid water was very different among the hardwood species. The MIP technique appeared as an important tool to evaluate the fluid paths within wood, which permitted the prediction of water behavior in wood during drainage from full saturation at high RH. Quantitative anatomical results were very useful for explaining the first steps of drainage and mercury penetration in wood.     

玉米果穗顶部籽粒败育的形态解剖观察

通过对正常粒和败育粒胚胎发育的形态解剖观察,明确了凡是能抽出花丝的各部位小花,在授粉前基本上均可发育成完整的成熟胚囊,仅在胚囊大小上有所差别。授粉后不同位势间胚乳和胚的分化发育存有一定差异,开始表现在时间早晚、数量多少、形态及大小不同等方面,最终导致劣势位粒（穗顶部）的败育。发生粒败育的重要原因是在发育过程中籽粒间的营养竞争和物质分配不均衡、穗顶部籽粒缺乏足够的养分所致。籽粒败育首先是胚乳发生败育,使胚的分化发育失去了物质供应来源,胚的分化发育受阻。籽粒败育的决定时期以胚乳败育为转折点,早者在授粉后8-12天,晚者在授粉后16-21天。     

双峰驼的下颌神经

运用大体解剖学方法对5例骆驼头左右两侧进行详细的解剖,以研究双峰驼的下颌神经。双峰驼的下颌神经的主要分支有颞深神经、咬肌神经、颊神经、舌神经、下齿槽神经、下颌舌骨肌神经、翼内侧肌神经、翼外侧肌神经和耳颞神经。颊神经在其起始部有较粗的交通支与上颌神经和腭大神经相连;在颊后部外侧面分为7～8条小支,形成颊神经丛。双峰驼有1～2个颏副孔,下齿槽神经在下颌管内分出1～2条颏副神经,穿经颏副孔,分布于颊及下唇。     

西瓜营养器官解剖学研究

西瓜的营养器官结构如下：（１）幼根由表皮、皮层和维管柱三部分组成，初生木质部为四原型；成熟根具有一定的次生结构，维管束为外韧型。（２）下胚轴的初生结构由表皮、皮层、维管束、髓和髓射线等构成，维管束为双韧型；次生生长时形成层主要存在于外韧皮部和木质部之间，为有限的次生生长。（３）地上茎的结构较复杂，初生结构中维管束排列近两轮；次生生长与下胚轴大致相似。（４）卷须的结构与茎的基本相似。（５）子叶与叶片均由表皮、皮层和叶脉三部分构成，叶片为典型的异面叶。     

紫杉种子形态解剖的初步研究

该文借助于立体解剖镜、显微镜对紫杉种子的形态及构造进行了观察和描述，同时，利用扫描电子显微镜拍摄了种子外形、种子纵切面和种皮层次的电镜照片，初步摸清了紫杉种子的外部形态和内部构造，目的为紫杉资源的开发、利用及遗传育种方面提供理论上的依据。