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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
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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
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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
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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
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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
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正常微生物群是一个新的人体生理学系统 总被引:15,自引:4,他引:15
康白 《中国微生态学杂志》2003,15(2):63-65
1 前言微生态学的发展 ,现在已把微生物的作用 ,从主要是致病作用的观点转移到主要是生理作用的观点。这种观点的转变是经过 10 0多年的学术研究和科学发展才取得的。在 2 0世纪经过无菌动物的饲养、厌氧培养技术的进步和现代分子生物学、基因工程学的研究终于完成了微生态学向新的更高阶段的转变。这就是微生物的研究以致病性为主的时代转向以生理性为主的时代。要确定一门新学科的诞生日期是很难的。一门新学科的定义也是逐渐形成的 ,要经过科研成果不断积累才能逐渐完善。正常微生物群的生理作用的提出是很早的 ,至少要推衍到 19世纪的… 相似文献
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Forty-nine methanol extracts of 37 species of Malaysian medicinal plants were investigated for their inhibitory effects on platelet-activating factor (PAF) binding to rabbit platelets, using 3H-PAF as a ligand. Among them, the extracts of six Zingiberaceae species (Alpinia galanga Swartz., Boesenbergia pandurata Roxb., Curcuma ochorrhiza Val., C. aeruginosa Roxb., Zingiber officinale Rosc. and Z. zerumbet Koenig.), two Cinnamomum species (C. altissimum Kosterm. and C. pubescens Kochummen.), Goniothalamus malayanus Hook. f. Momordica charantia Linn. and Piper aduncum L. are potential sources of new PAF antagonists, as they showed significant inhibitory effects with IC50 values ranging from 1.2 to 18.4 microg ml(-1). 相似文献
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报道了中国姜科山姜属植物1新记录种:灰岩山姜(Alpinia calcicola),并提供形态特征描述、地理分布及彩色图片。凭证标本保存在中国科学院华南植物园标本馆(IBSC)。 相似文献
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巴戟天(Morinda officinalis How)系茜草科巴戟天属植物,本文对它作了宏观和微观的形态结构观察及植物学和《本草》重新考察;对三个混淆种亦进行了解剖研究,并根据它们的解剖要征,如同在第326页的分种检索表中一样,彼此间能够加以区别;此外,对二个非常难以区分的种类,即副巴戟和正品巴戟天,在外部形态的研究过程中,发现它们在花冠上的毛状体的分布和特征,彼此间也可以区别。 相似文献
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Supriyo Basak Ramesh Aadi Moolam Ajay Parida Sudip Mitra Latha Rangan 《Plant Diversity》2019,(3):206-211
Accurate detection of unique herbs is crucial for herbal medicine preparation. Zingiberaceae species, which are important in Ayurvedic medicine of India, are often misidentified in Northeast (NE) Indian herbal markets. Kaempferia galanga (Zingiberaceae) is one of the major components of popular Ayurvedic drugs used for rheumatic diseases (i.e.,“Gandha Thailam” and “Rasnairandadi Kashayam”), contusions, fractures, and sprains. In NE India, herbal healers often misidentify plants from the Marantaceae family (e.g., Calathea bachemiana and Maranta leuconeura) as Kaempferia, which leads to adulteration of the medicinal herb. This misidentification of herbs occurs in NE India because Zingiberaceae plant barcoding information is inadequate. As a consequence, herbal medicine is not only therapeutically less effective but may also cause adverse reactions that range from mild to life-threatening. In this study, we used eight barcoding loci to develop “fingerprints” for four Kaempferia species and two species frequently mistaken for Kaempferia. The PCR and sequencing success of the loci matK, rbcL and trnH-psbA were found to be 100%;the combination of matK, rbcL, and trnH-psbA proved to be the ideal locus for discriminating the Kaempferia species from their adulterants because the combined loci showed greater variability than individual loci. This reliable tool was therefore developed in the current study for accurate identification of Kaempferia plants which can effectively resolve identification issues for herbal healers. 相似文献
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Autonomous self pollination is considered to be a reproductive assurance mechanism for plants when facing extreme environments that scarce in pollinators, and it also has disadvantages like inbreeding depression and pollen/ovule discounting. In several genera of Zingiberaceae like Alpinia and Amomum, a specialized mechanism named flexistyly exists, precedent studies consider its significance as preventing unnecessary self pollination and sexual interference. However according to our field observation, if pollen grains on cataflexistylous (CATA) flowers remain on the anther when the style curves downwardly, potential exists that the stigma contacts the pollen, thus autonomous self pollination occurs. Here, we studied the breeding system of Alpinia galanga, the results show that (1) Alpinia galanga is self compatible in which inbreeding depression occurs to some degree; (2) The anaflexistylous (ANA) morph of Alpinia galanga allocates more resource into outcrossing than the CATA morph; (3) The P/O ratio of the ANA morph is significantly lower than that of the CATA morph, as Alpinia galanga has constant six ovules in each ovary, the significant difference in P/O value reflects the contrast in pollen production. This phenomenon may be interpreted as the ANA morph provides pollen exclusively for the CATA morph. But the CATA morph, despite delivers pollen to the ANA morph, also need its own pollen for potential autonomous self pollination. In summary, autonomous self pollination exists in Alpinia galanga, and while flexistyly functions to avoid unnecessary self pollination and sexual interference, it also provides advantages for delayed autonomous self pollination as a necessary reproductive assurance and preventing conflict among these three major features by controlling the time of autonomous self pollination. This peculiar mechanism in Alpinia galanga thoroughly demonstrates its adaptation to unfavorable surrounding during the evolutionary process. 相似文献
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Palynology of South Indian Zingiberaceae 总被引:1,自引:0,他引:1
JOSE K. MANGALY JYOTHI NAYAR 《Botanical journal of the Linnean Society. Linnean Society of London》1990,103(4):351-366
MANGALY, J. K. & NAYAR, J. 1990. Palynology of South Indian Zingiberaceae. Light microscope studies on pollen morphology of 21 Old World, tropical taxa of Zingiberaceae reveal that an exine is absent only in Kaempferia . A discontinuous exine layer consisting of circular plates joined together at margins occurs in Alpinia galanga and Amomum hypoleucum while all other taxa possess an uninterrupted exine layer which is commonly 0.7 μm to less than 2.0 μrn thick (3.2 μm in Zingiber zerumbet , 2.5 μm in Amomum hypoleucum ). Exine is spinose in Alpinia (smooth in Alpinia sanderae ), Amomum and Boesenbergia , verrucose in Eleltaria , tuberculate to areolate or striate in Zingiber , papillose in Globba and smooth or nearly so in Curcuma, Costus and Hedychiurn . Pollen grains are spheroidal, 50–90 μm in size (35 μm in Globba ophioglossa ), and inaparturate (foraminate in Costus ), except in Curcuma and Zingiber where they are ovoid to ellipsoidal, 70–135 times 60–80 μm in size and sulcate. A lamellated intine, much thicker than the exine, occurs in all, and it is thinner at the apertural region in Curcuma, Costus and Zingiber; in Elettaria and Hedychiurn it is thinner in one or few large scattered circular areas, and in Boesenbergia and Alpinia zerumbet on one side of the grains. Palynologirally Alpinia, Amomum, Boesenbergia, Kaempferia and Zingiber constitute one group while Elettaria, Hedychiurn and Costus constitute another. 相似文献
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益智(Alpinia oxyphylla)的花期从2月底至4月下旬;单株花期(花序)约为16~26 d,通常为23~26 d;单花花期一般为1 d。正常情况下,益智和其它山姜属植物一样,具有花柱卷曲性促进异花授粉的机制,表现出两种类型:花柱上举型和花柱下垂型,其花柱卷曲运动的节律与其它已报道的山姜属植物基本一致。但观察发现,当遭遇低温天气时(日最高气温<18℃),单花花期延长为2 d,无论是上举型个体还是下垂型个体,均只表现出一种花型——下垂型:上午开花时花柱弯向上,柱头位于已开裂散发出花粉的花药上方,直到第二天上午6∶30~11∶00间,花柱才陆续地慢慢向下运动,柱头下降至与花药等高或位于花药下方。益智的主要传粉昆虫是蜜蜂(Apidae sp.)、木蜂(Xylocopa sp.),绝大多数的访花者的访花目的是吸蜜。益智的花蜜分泌量(8.37~15.79 μl)和花蜜含糖量(30.12%~32.83%)较高,花蜜是益智作为传粉者访花的最主要的报酬。实验结果还表明,益智花部中唇瓣对昆虫访花有显著的招引作用;益智的花蜜对蜜蜂的访花频率有显著的影响,对木蜂有一定的招引作用,但并不显著。而花粉(花药)则对昆虫的访花频率影响不大。人工授粉实验结果表明益智存在自交亲和性,无论是上举型或下垂型个体自交和异交均有较高的结实率;人工自交和异交的结实率在上举型植株中存在较大的差异,而在下垂型个体中则差异不明显;去雄套袋、去柱头套袋和完全套袋不授粉等处理均不结实,表明益智不存在无融合生殖现象和自动自花授粉现象。益智的繁育系统是异花授粉交配系统。 相似文献