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21.
医学院校生物类专业人才培养模式探讨 总被引:2,自引:0,他引:2
目前全国年产值过亿元的生物技术企业已蓬勃发展起来,未来一段时期我国对生物技术人才仍有极大需求,具有中医药背景的生物类专业人才培养是生物科技经济发展的需要。为此,结合实际对中医药背景生物类专业需求、现状和在该类人才培养过程中的经验体会进行初步探讨。 相似文献
22.
安梅 《上海师范大学学报(哲学社会科学版)》2008,37(3):122-127
实验教学是高中生命科学教学中的重要环节,合理运用显微数码互动系统能在一定程度上克服传统生物实验教学的局限性。研究表明,运用该系统在提高课堂效率,增加师生沟通、实现资源共享,推动高中生命科学基础型、拓展型、研究型三类课程发展等方面发挥了积极的作用,提升了高中生命科学实验教学的质量,并带来实验教学观念上的更新。 相似文献
23.
本文就我国具有代表性的草型湖泊——东太湖的生物资源和环境状况进行了分析,在此基础上探讨了生物资源的开发,同时根据东太湖生态特点提出了切实可行的生态环境保护对策,以期为草型湖泊的开发和保护提供参考。 相似文献
24.
25.
运用人体生物钟节律把握教育时机 总被引:5,自引:0,他引:5
对于人体生物钟的研究已经有一个世纪了。虽然人们对于它的评价褒贬不一,在争论中也有人说它是伪科学,但人体生物钟节律理论在人们的日常生活和产生中起着重要作用,应用广泛。而它应用于教与学的研究目前尚少。教师和学生了解并运用自身的生物钟规律,有利于把握教与学的时机,提高教学的效率。 相似文献
26.
INTRODUCTIONCiliaryneurotrophicfactor (CNTF)isanat urallyoccurringproteinwithamolecularmassofapproximately 2 2kDa .Itisexpressedinglialcellswithinthecentralandperipheralnervoussystems.CNTFstimulatesgeneexpression ,cellsurvivalordifferentiationinavarietyof… 相似文献
27.
基于ECOPATH模型的东海区生物资源能量流动规律的初步研究 总被引:3,自引:1,他引:2
本文根据国际水生资源管理中心网站的东海区生物资源数据和历史资料数据,利用Ecopath模型对东海区生物资源能量流动规律进行了初步研究。东海生态系统存在4个营养级,第一营养级是碎屑和浮游植物;第二营养级是一些草食性的动物;第三营养级为第一级肉食动物;第四营养级为第二级肉食动物,并且大多为杂食性鱼类。东海区生态系统分为32个功能组。东海区Ecopath模型基本参数主要有:生物量(B)、生产量与生物量的比值(P/B)、消耗量与生物量的比值(Q/B)和生态转移效率(EE)。Ecopath模型分析结果显示,总捕获为5.761t(/km2·a)、总消耗量为2621.630t/(km2·a)、总输出为106.339t/(km2·a)、流向碎屑总量为1303.487t(/km2·a),总生物量(不包含碎屑)为73.478t/km2,系统总流量为5393t(/km2·a),数据表明东海区的营养水平、生产力水平和饵料生物水平都处于一个良好的状态;初级生产力与呼吸量的比值为0.825,说明东海区生物资源栖息环境质量处于较好的水平;生态系统连接指数和系统杂合度分别为0.172和0.199,表明东海区生态系统不同营养级之间的捕食活动复杂性还比较低;捕获平均营养级为3.1,较往年有所降低,说明东海区的生物资源处于退化状态。 相似文献
28.
Ross H. Sanders 《Journal of sports sciences》2013,31(2):213-227
Abstract The purpose of this study was to establish the characteristics of the movement patterns common to flutter kicking of skilled swimmers and to determine how the movement patterns of swimmers at different levels of a “learn-to-swim” programme differ from those of skilled swimmers. Also, the nature of the skill afforded the opportunity to investigate learning of a cyclical multi-joint task from a motor control perspective. The underwater motion of nine children representing three levels of a “learn-to-swim” programme and 10 skilled swimmers were video-recorded while performing nine cycles of prone flutter kicking. Kinematics including joint angular motion and coordination of joint actions were calculated. Fourier analysis was applied to determine the frequency composition of the vertical undulations of the hip, knee, and ankle and to calculate the velocity of the body wave travelling caudally from hip to ankle. Fourier analysis also enabled investigation of biological noise, as distinct from variability. The results indicated the desired joint angles and coordination towards which learners could be guided. An index based on the ratio of hip – knee and knee – ankle body wave velocities showed that the inter-joint coordination of most learners was not appropriate for effective flutter kicking. There was strong evidence to suggest that skilled performance in flutter kicking is characterized by sequencing of joint actions to produce a single sinusoidal body wave moving caudally with not decreasing and preferably increasing velocity, low biological noise, and small variability. 相似文献
29.
Ciliary neurotrophic factor (CNTF) has pleiotropic actions on many neuronal populations as well as on glia. Signal transduction
by CNTF requires that it bind first to CNTF-R, permitting the recruitment of gp130 and LIF-R, forming a tripartite receptor
complex. Cells that only express gp130 and LIF-R, but not CNTF-R are refractory to stimulation by CNTF. On many target cells
CNTF only acts in the presence of its specific agonistic soluble receptors. We engineered a soluble fusion protein by linking
the COOH-terminus of sCNTF-R to the NH2-terminus of CNTF. Recombinant CNTF/sCNTF-R fusion protein (Hyper-CNTF) was successfully expressed in COS-7 cells. The apparent
molecular mass of the Hyper-CNTF protein was estimated from western blots to be 75 kDa. Proliferation assays of transfected
BAF/3 cells in response to CNTF and Hyper-CNTF were used to verify the activity of the cytokines. The proliferative results
confirmed that CNTF required homodimerization of the gp130, CNTF-R and LIF-R receptor subunit whereas Hyper-CNTF required
heterodimerization of the gp130 and LIF-R receptor subunit. We concluded that the fusion protein Hyper-CNTF had superagonistic
activity on target cells expressing gp130 and LIF-R, but lacking membrane-bound CNTF-R.
Project supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholar, Zhejiang Province, China
and SFB415, TP B5, Germany. 相似文献
30.
Scrubbing of NO
x
from the gas phase with Fe(II)EDTA has been shown to be highly effective. A new biological method can be used to convert
NO to N2 and regenerate the chelating agent Fe(II)EDTA for continuous NO absorption. The core of this biological regeneration is how
to effectively simultaneous reduce Fe(III)EDTA and Fe(II)EDTA-NO, two mainly products in the ferrous chelate absorption solution.
The biological reduction rate of Fe(III)EDTA plays a main role for the NO
x
removal efficiency. In this paper, a bacterial strain identified asKlebsiella Trevisan sp. was used to demonstrate an inhibition of Fe(III)EDTA reduction in the presence of Fe(II)EDTA-NO. The competitive inhibition
experiments indicted that Fe(II)EDTA-NO inhibited not only the growth rate of the iron-reduction bacterial strain but also
the Fe(III)EDTA reduction rate. Cell growth rate and Fe(III)EDTA reduction rate decreased with increasing Fe(II)EDTA-NO concentration
in the solution.
Project (No. 20176052) supported by the National Natural Science Foundation of China and the Scientific Research Foundation
for Returned Overseas Chinese Scholars, Ministry of Education 相似文献