首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 359 毫秒
1.
“对立统一规律是宇宙的根本规律。”动物体是完整统一的有机体,其各系统、各器官的机能活动是矛盾的,对立的,同时又是统一的。心脏的跳动,肺脏的呼吸,肌肉的伸缩,胃肠的蠕动等,都是由相互联系、相互制约的对立统一的活动完成的。在这些活动当中,神经系统起着主要的调节作用。中枢神经系统是支配全身活动的中枢,而内脏器官的活动是由相对自主的植  相似文献   

2.
生理生态学的原则是随着纬度的升高,物种分布的海拔高度将随之降低。但是,云南一些植物特征成分的分布却与之相反,它们的分布与云南残留的古夷平面的分布相似,即随着纬度的升高,其分布的海拔高度也随之升高。二者的区别是云南古夷平面分布的趋势线的仰角大于那些特征成分分布的趋势线的仰角。可能的原因是:相对于剧烈的地质运动,物种的适应能力总是相对滞后的,并且物种的分布也受到其生长特性的制约;根据分布区形成的原则,这些成分的发生应早于夷平面的隆起。  相似文献   

3.
制作学案的过程,就是老师理解通透所传授的知识的前提下,阅读大量的相关的资料,根据学生的认知水平与知识的积累能力,为指导学生进行主动的知识建构而编制的学习方案,以便积极引导和帮助学生的自主学习的能力进行探究思索的方案。高中生物的教学研究问题,通过学案的方式向学生传授知识,是教师在教学理论与学习标准的指导下对高中生物的教学所提高的一个新层次。  相似文献   

4.
浅谈果树病虫害综合防治技术研究   总被引:2,自引:0,他引:2  
在我国的农业生产的过程中,对于果树的病虫害综合防治是农业生产效益的根本保障,我国是一个农业大国,尤其是在我国的北方,果树的栽培更是有着悠久的历史,在近些年中由于技术的进步果树的品种更新的速度也在不断的加快,但是随之而来的就是果树的病虫害的问题,它对于果树的影响非常的大,直接在经济上给果农带来严重的损失,为了能够让果农的经济效益得到保障,对于果树的病虫害防治就显得极为重要。本文主要是对东北地区的果树病虫害的现状进行简要的分析,并对果树病虫害的综合防治技术进行研究找出适当的对策,希望能有所裨益。  相似文献   

5.
随着社会的发展经济的进步我国在各个领域的发展上都得到了相应的提升,从农业的发展情况来看,由于我国在科学技术上进步故此在农业的发展上也取得了重大的成效,但是在农业发展的过程中也出现了一些严重的问题,就是对于化学药品的使用所造成的农产品的污染以及环境的污染。本文主要针对当前的一些植物保护的现状进行阐述,并对植物保护和农业的可持续发展间的关系进行了详细的分析探究,希望能够在此领域的学术发展起到一定的参考作用。  相似文献   

6.
本文采用双积分球测量系统和Inverse Add ing-Doub ling方法,研究了自然和热凝固的人肝组织对532nm的KTP激光和1 064 nm的Nd:YAG激光的光学特性。结果表明:热凝固的人肝组织对532 nm的KTP激光的吸收系数较自然的肝组织的吸收系数增大了23.5%(P<0.05),热凝固的肝组织对1 064 nm的Nd:YAG激光的吸收系数较自然的肝组织的吸收系数减小了34.3%(P<0.05)。热凝固的人肝组织对532 nm的KTP激光的散射系数较自然的肝组织的散射系数增大了4.50倍(P<0.05),热凝固的肝组织对1 064 nm的Nd:YAG激光的散射系数较自然的肝组织的散射系数增大了6.41倍(P<0.05)。热凝固的人肝组织对532 nm的KTP激光的各向异性因子较自然的肝组织的各向异性因子减小了5.47%,热凝固的肝组织对1 064 nm的Nd:YAG激光的各向异性因子较自然的肝组织的各向异性因子减小了1.95%。  相似文献   

7.
在当前的形势下,我国的林业建设工作也是需要及时的调整发展方案,以此来适应新时代的发展的,要由传统的林业建设模式逐渐的向现代化的方向发展。从某种程度上来说,基层林业站的微观变化也会对林业建设的发展方向的宏观调整产生直接的影响,因此,要结合科学发展的建设理念,来指导林业站的工作,以此来促进林业的健康建设。文章主要阐述基层林业站的作用,主要是为更好的发挥基层林业站的效用服务的。  相似文献   

8.
一、植物生理学面临的挑战作为植物学的一个重要分支的植物生理学经过百余年的发展对植物生命活动的基本规律及其与环境的关系的了解取得了长足的进展,也对人类的生产活动起了巨大的促进作用。例如化学肥料及生长调节剂与除草剂的大规模应用,细胞全能性的发现及利用等。但与现代自然科学体系日新月异的进步相比植物生理学则象百舸竞渡中的一叶扁舟,面临着严峻的挑战。近年分子生物学和遗传学的飞速进步,各种物理化学检测手段的应用及检测精度的提高,使植物生理学的机理的探索必须建立在分子生物学的基础上并相应地使用精确的检测手段,例如植物激素乙烯的发现及其生物合成与作用机理的研究,就是建  相似文献   

9.
绪言自从1950年召开的研究巴甫洛夫生理学说问题的苏联科学院及苏联医学科学院的科学会议以后,则产生了根据巴甫洛夫学说讲授中学的人体解剖生理学的必要性. 巴甫洛夫的高级神经活动学说是他的生理学说的顶峰,是中学学生所必需获得的,巴甫洛夫有关高级神经活动的概念,可以在人体解剖生理课程中阐明,但是它的形成在动物学的课程中就应当开始.高级神经活动的概念,在说明关于有机体为统一的整体的较为总括性的概念中,是起一个主导作用的.学生自觉的掌握巴甫洛夫的“高级神经活动”概念,将会有助于学生树立辩证唯物主义的、无神论的世界观.学生具备了高级神经活动的概念,则给中学10年级学习心理学打下了良好的基础.一直到现在为止,在学校的人体解剖生理学课程中树立高级神经活动概念的方法的问题,尚未得到必要的解决.  相似文献   

10.
对于罗红来说,热爱自然始于被自然的征服,始于非洲的原野上“生命就在你身边奔流”的时候,发现了“那么多的生命可以跟人类如此之近,有多美好”。同时也始于被蹂躏的自然的伤痛。于是他的镜头,才可能在动物的世界里,创造出“那么多让人热血沸腾的故事”。从一个旁观者的角度,进入到撼人心魄的生物圈,然后又选择了从数千米的高空,俯瞰这个世界的美丽。距离的远近不是心灵远近的同义词,罗红大气、美丽的自然,说出了一个普通而又意味深长的哲理。以一种爱的力量在很近的心灵的距离俯瞰宏大的自然,世界才会呈现出完全不同的意味。当然,这样的一个过程,是漫长而艰巨的,也是值得的。[编者按]  相似文献   

11.
A tabular synopsis is presented for articles concerned with the effects of peptides on the central nervous system that appeared in the journal Peptides from 1980-1985. A table arranged alphabetically by peptide and one arranged by effects, both listing routes of injection, species, direction of change, and qualifying notes, provides easy cross-referencing of peptides and their effects. Over 80 peptides and over 135 effects are listed. The list of peptides includes, but is not limited to: ACTH, angiotensin, bombesin, bradykinin, calcitonin, casomorphin, CCK, ceruletide, CGRP, CRF, dermorphin, DSIP, dynorphin, endorphins, enkephalins, GRF, gastrin, LHRH, litorin, metkephamid, MIF-l, motilin, MSH, NPY, NT, oxytocin, ranatensin, sauvagine, substances P and K, somatostatin, TRH, VIP, vasopressin, and vasotocin. The list of effects includes, but is not limited to: aggression, alcohol, analgesia, attention, avoidance, behavior, cardiovascular regulation, catalepsy, conditioned behavior, convulsions, dopamine binding and metabolism, discrimination, drinking, EEG, exploration, feeding, fever, gastric secretion, GI motility, grooming, learning, locomotor behavior, mating, memory, neuronal activity, open field, operant behavior, rearing, respiration, satiety, scratching, seizure, sleep, stereotypy, temperature, thermoregulation and tolerance.  相似文献   

12.
13.
油菜(Brassica campestrisLinn.var.oleifera DC.)花粉含有七种可溶性糖和一个中性多糖;十七种游离氨基酸和十八种水解氨基酸;十一种维生素;四种黄酮类化合物;九种脂肪酸;五种有机酸和廿二种矿质元素。因此,油菜花粉是一种营养与有效成份极其丰富的营养品。  相似文献   

14.
Chromosome counts are presented for 217 species of 103 genera of grasses from Costa Rica. Four of the genera and 90 of the species are reported for the first time. In addition, 26 counts differ from previous records for the same taxon. The generaGynerium, Lithachne, Luziola, andThrasya were heretofore unknown cytologically. First counts are also given for the following species:Agrostis bacillata, A. pittieri, A. sub patens, Andropogon angustatus, A. bicornis, A. virgatus, Aristida capillacea, A. jorullensis, Arundinella berteroniana, A. deppeana, Axonopus aureus, A. capillaris, A. chrysoblepharis, Bouteloua americana, B. disticha, Bromus exaltatus, Calamagrostis intermedia, C. nuda, C. pittieri, Chusquea lehmannii, C. tonduzii, Cinna poaeformis, Deschampsia pringlei, Digitaria panicea, Echinochloa polystachya, Echinolaena gracilis, Eragrostis simplicijlora, Eriochloa distachya, E. polystachya, Eriochrysis cayennensis, Festuca dolichophylla, Gymnopogon fastigiatus, Gynerium sagittatum, Hymenachne amplexicaulis, Imperata contracta, Isachne polygonoides, Ischaemum latijolium, Lithachne pauciflora, Luziola fragilis, Manisuris aurita, Panicum aquaticum, P. arundinariae, P. boliviense, P. cordovense, P. grande, P. haenkeanum, P. milleflorum, P. parviglume, P. pilosum, P. polygonatum, P. rudgei, P. stenodes, P. trichanthum, P. trichoides, P. viscidellum, Paspalum candidum, P. centrale, P. decumbens, P. fasciculatum, P. jimenezii, P. microstachyum, P. multicaule, P. nutans, P. parviflorum, P. pilosum, P. prostratum, P. pumilum, P. reclinatum, P. saccharoides, P. scabrum, P. serratum, P. squamulatum, P. standleyi, Pennisetum bambusiforme, P. distachyum, Pereilema beyrichianum, Pharus parvifolius, Sacciolepis myuros, Schizachyrium condensatum, Sorghastrum incompletum, Sporobolus ciliatus, S. purpurascens, Streptochaeta sodiroana, Thrasya gracilis, T. petrosa, T. robusta, Trisetum pringlei, T. tonduzii, Uniola pittieri, and Zeugites pittieri. In addition, the following counts are different from previous records for the same taxon:Aegopogon cenchroides, Axonopus poiophyllus, Bouteloua media, Brachiaria plantaginea, Chusquea subtessellata, Digitaria adscendens, Homolepis aturensis, Hymenachne donacifolia, Ichnanthus axillaris, I. pallens, I. tenuis, Ischaemum ciliare, Ixophorus unisetus, Oplismenus burmannii, O. hirtellus, Panicum geminatum, P. glutinosum, P. mertensii, P. parvifolium, P. sellowii, Paspalum convexum, Pennisetum nervosum, P. setosum, Polypogon elongalus, Raddia costaricensis, Schizachyrium hirtijlorum.  相似文献   

15.
The O-antigenic relationships between Hafnia and Shigellae (S. flexneri and S. boydii) have been studied. For the first time the presence of antigenic relationship between Hafnia O19, O4, O9, O33, O5, O16, O12, O7, O29, O28, O10, O32, O24, O25, O18, O1, O13, O3, O22, O30, O37, O14, O11, O25, O23, O21, O28, O16, O24, O8, O26, O27 and S. flexneri la, lb, 2a, 2b, 4a, 4b, 6, 5a, 5b, as well as between Hafnia O10, O21, O35, O36, O9, O28, O8, O30 and S. boydii 1, 3, 6, 14, 2, 5, 2, 12 have been revealed. The character and degree of manifestation of antigenic relationships between the above-mentioned groups of bacteria have been established.  相似文献   

16.
边禄森  戴玉成 《生态学报》2015,35(5):1554-1563
对东喜马拉雅地区多孔菌区系和生态习性进行了分析,发现该地区多孔菌极为丰富,共有10目19科101属372种,其中优势科为多孔菌科和锈革孔菌科,优势属为木层孔菌属和多孔菌属。种的区系地理成分可以分为8类,其中北温带类型种类最多,表明东喜马拉雅地区多孔菌具有明显的北温带区系特征。该地区的多孔菌有常见种、偶见种、稀有种和濒危种分别为156、141、54和21个;有腐生菌304种、寄生菌49种、菌根菌19种。在寄主方面,能够生长在被子植物上的有256种,裸子植物上的有137种,既能生长在被子植物,也能生长在裸子植物上的有40种,地上生长的有19种。东喜马拉雅地区的裸子植物,特别是云杉属、松属和冷杉属树木对于多孔菌的生长更重要,因为生长在这些属树木上的多孔菌分别有71、68和51种,高于该地区被子植物其他属树木上的多孔菌。  相似文献   

17.
In order to determine any possible relation between chemical composition of a person’s blood to formation of dental caries, whole blood was analyzed for 35 inorganic elements (Si, Al, Fe, Ca, Mg, K, Mn, Ti, P, Li, Be, B, V, Cr, Co, Ni, Cu, Zn, As, Sr, Y, Nb, Mo, Ag, Cd, Sn, Sb, Ba, La, Ce, W, Pb, Bi, Zr, and F) in the 15 people having sound teeth as well as an equal number of those having multiple caries. The results showed the absence of 13 elements (Si, Al, Mn, Ti, Be, Co, As, Y, Cd, Ba, La, Ce, and Zr) in the blood of both groups. Of the remaining 22 elements, the results of only seven elements (Fe, P, B, V, Sr, Sn, and F) were significantly different between the two groups. The most remarkable finding of this study was significantly decreased amount of phosphorus, strontium, and fluorine and perhaps increased boron in the blood of persons with caries.  相似文献   

18.
On the basis of a review of the approximately 4300 species of apicomplexan protozoa, the following new species, new names, new combinations, and emendations are given: NEW GENUS, Erhardovina; NEW SPECIES, Ascogregarina polynesiensis, Eimeria golemanskii, Isospora tamariscini; NEW NAME, Gregarina kazumii; NEW COMBINATIONS, Ascogregarina brachyceri (Purrini, 1980), Erhardovina euzeti (Lipa, 1981), E. scutovertexi (Erhardová, 1955), Haemorhormidium batrachi (Chaudhuri & Choudhury, 1983); EMENDATIONS, Selenidium francianum (Arvy, 1952) Tuzet & Ormières, 1965, Pyxinioides bolitoides D. P. Henry, 1938, P. japonicus H. Hoshide, 1951, P. kamenote H. Hoshide, 1951, P. kurofuji H. Hoshide, 1951, P. oshoroensis H. Hoshide, 1951, P. pugetensis D. P. Henry, 1938, Gregarina levinei Haldar & Sarkar, 1980, Retractocephalus halticae Haldar, Chakraborty & Kundu, 1982, Cnemidospora schizophylli Tuzet & Guerin, 1947, Grebneckiella indica (Merton, 1911) Watson, 1916, Quadruspinospora atractomorphae Haldar & Chakraborty, 1978, Haemogregarina acipenseri Nawrotzky, 1914, H. lobianci Yakimov & Kohl-Yakimov, 1912, H. yakimovikohlae Wladimiroff, 1910, Hepatozoon luehi (Sambon, 1909) Pessoa, Cavalheiro & de Souza, 1970, Eimeria beyerae Ovezmukhammedov, 1977, E. (?) gigantea (Labbé, 1896) Reichenow, 1921, E. (?) labbei Hardcastle, 1943, E. rufi Prasad, 1960, E. (?) scylii (Drago, 1902) Levine & Becker, 1933, Isospora corvi Ray, Shivnani, Oommen & Bhaskaran, 1952, I. melopsittaci Bhatia, Chauhan, Arora & Agrawal, 1973, I. seicerci Ray, Shivnani, Oommen & Bhaskaran, 1952, I. stomatici Chakravarty & Kar, 1944, I. triffitae Nukerbaeva & Svanbaev, 1973, Wenyonella mackinnonae Misra, 1947, Octosporella sanguinolentae Ovezmukhammedov, 1975, Lankesterella millani Alvarez Calvo, 1975, Sarcocystis woodhousei Dogel', 1916, Haemoproteus lari Yakunin, 1972, Babesia ninakohlyakimovae (Yakimoff & Shokhor, 1916), Theileria ninakohlyakimovae (Yakimov, 1916) Krylov, 1974, Haemohormidium batrachi (Chaudhuri & Choudhury, 1983).  相似文献   

19.
Little is known about the link between metals accumulated in human and asbestos fiber contamination in the environment. Therefore, hair samples of 368 subjects (128 males and 240 females) from a rural area contaminated by crocidolite asbestos fibers were collected to investigate the distributions of 17 metals accumulated in human. The results showed that the mean concentrations of As, Al, Ba, Cd, Co, Cr, Cu, Fe, Hg, Mg, Mn, Mo, Na, Ni, Pb, Sr, and Zn in hair of the total subjects were 0.23, 23.36, 4.33, 0.11, 0.05, 0.70, 10.53, 29.74, 0.37, 241.57, 3.52, 0.08, 153.21, 0.72, 4.26, 10.96, and 113.35 mg/kg, respectively. Moreover, approximately 86.14, 52.17, 73.91, 85.05, 80.98, 74.46, and 53.80 % of the hair samples of the total subjects contained much higher concentrations of Al, Ba, Fe, Mg, Mn, Na, and Sr compared with the highest reference values, respectively. The mean concentrations of the determined metals (except for As, Co, Cr, Hg, and Mo) significantly varied among different age groups for both male and females. The results of correlation analysis and cluster analysis revealed that strong correlations were found between Al, Fe, Zn, Mg, and Na accumulated in human from the study area. These might suggest that Al, Ba, Fe, Mg, Mn, Na, and Sr were significantly derived from contamination of crocidolite asbestos fibers. Zn, Mg, and Na might also originate from diet. However, Cd, Mo, Co, As, Cr, Hg, Ni, Mn, Pb, and Ba accumulated in human seemed to be mainly derived from soil. It can be concluded that metals accumulated in human hair have a link with asbestos fiber contamination in the environment.  相似文献   

20.
To estimate the applicability of yeastSaccharomyces cerevisiae as a radioisotope accumulator, biosorption of 18 radionuclides (isotopes of Be, Na, Sc, V, Cr, Mn, Fe, Co, Zn, As, Se, Rb, Sr, Y, Zr, Tc, Ru, and Rh) by the cells was tested using a multitracer technique. This technique enables us to examine the uptake of various elements under an identical condition. We showed that the yeast has ability to take up radioactive tracers of Be, Sc, V, Cr, Mn, Fe, Co, Zn, As, Se, Sr, Y, Zr, Ru, and Rh from an aqueous environment. Tracers of Be, Sc, Mn, Co, Zn, Se, Sr, Y, and Zr were distributed in both cell walls and other cell parts. Moreover, tracers of Sc, Mn, Co, Zn, Se, Sr, and Y were present as soluble and insoluble forms, and most of the Be and Zr were present as an insoluble form in the cells.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号