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1.
生态交错带与生态流   总被引:34,自引:2,他引:32  
生态交错带与生态流王庆锁(中国农业科学院畜牧研究所,北京100094)冯宗炜罗菊春(中国科学院生态环境中心,100080)(北京林业大学,100083)EcotonesandEcologicalFlows.WangQingsuo(AnimalHus...  相似文献   

2.
贵州省西北部“百里杜鹃林”的土壤生态条件   总被引:6,自引:0,他引:6  
贵州省西北部“百里杜鹃林”的土壤生态条件庞纯焘,宋铭荷,田光普(贵州教育学院,贵阳550003)(贵州农学院,贵阳550006)SoilEcologicalConditionsinthe"HundredLi(500m)AzaleaForcst"inNorthwestGuizhouProvince¥PangChuntao;SongMinghe(GuizhouEducationCollege,Guiyang550003),TianGuangpu(GuizhouAgriculturalCollege,Guiyang550006).ChineseJournalofEcology,1993,12(1):49-52。Thereisavastareaofazalea(Rhododendronspp.)forestinNorthwestGuizhouProvince,Atfloweringseasoninsummer,itbecomesaregionoftouristattraction.Thisregionissofascinatingthatpeoplecallit"HundredLi(500m)AzaleaFores  相似文献   

3.
FactorsAffectingElectro-FusionandElectro-ActivationInSerialNuclearTransplantationInGoat(Carpahircus)EmbryoWANGYu-ge(王玉阁);ZOUX...  相似文献   

4.
ExpressionofPorcineGrowthHormoneGeneinCHOCellCHENQing-xuan(陈清轩);HEXin(何新);DENGHui-nan(邓辉南)(InstituteofDevelopmentalBiology,Ac...  相似文献   

5.
ExistenceandFunctionsofNeurotensinHumanEarlyPlacentalVilliZHANGChong-li(张崇理);CHENGLi-ren(程丽仁),SHENWei-bin(沈卫斌);YINHong(殷红);HU...  相似文献   

6.
GeneticEngineeringofTobaccowithDoubleResistancetoBothVirusandInsectLIANGXiao-you;(梁晓友)MIJing-jiu;(米景九),PanNai-sui(潘乃隧),CHENzh...  相似文献   

7.
不同生态条件下苹果叶面附生物种群演替的初步研究   总被引:2,自引:0,他引:2  
不同生态条件下苹果叶面附生物种群演替的初步研究陈功友,郑铁民,任国兰,时向阳(河南农业大学,郑州450002)郭艳春,宋爱仙(河南省植保总站,郑州450002)(郑州市园艺场,450002)SuccessionofEpiphyticMicrofloraPopulationsonApplePhylloplaneunderDiffcrentEcologicalCondi-tions¥.ChenGongyou,ZhengTiemin,RenGuolan,ShiXiangyang(Henan,AgriculturalUniuersity,Zhengzhou450002),GuoYanchun(HenanGeneralStationofplantprotection,Zhengzhou450002),SongAixian(HorliculturalFarmofZhengzhouMunicipality,Zhengzhou450002).(ChineseJournalofEcology,1993,12(4):7-13.Seasonalvariationsofepiphyticmicrofloraonapplephyll  相似文献   

8.
PEG-mediatedGeneTransferintoOrychophragmusViolaceusCotyledonProtoplastandRegenerationofTransgenicPlantsZHOUJi-ming(周冀明),WEIZh...  相似文献   

9.
全球温室气体排放概况   总被引:7,自引:0,他引:7  
全球温室气体排放概况曹志平(中国农业大学资源与环境学院生态系,北京100094)IntroductionofGlobalEmissionsofGreenhouseGas.CaoZhiping(ColegeofResourcesandEnvironm...  相似文献   

10.
小分子G蛋白Ras超家庭成员都是通过与鸟苷酸交换因子(guanine nucleotide exchange factors,GEFs)结合而被活化,GEFs能增加这类小分子G蛋白对GTP的摄取,并使之形成有活性的GTP结合构象。Rap1是Ras样的小分子G蛋白。迄今为止,已发现G3G、CalDAG-GEF1、Epac、cAM-GEF1、cAMP-GEFⅡ、nRapGEP、GFR可特异的活化Rap  相似文献   

11.
Four theoretical perspectives about why father involvement could have positive consequences for child development are briefly reviewed: attachment theory, social capital theory, Bronfenbrenner's ecological theory, and "essential father" theory. Strengths and weaknesses of each perspective are discussed, and the prospects for an integrated ecological-parental capital theory of paternal influence on child development are considered.  相似文献   

12.
Based on the theory of relationship between port and city and the theory of life cycle of the interactive development between the port and city,this article analyses the present situation of Qinhuangdao harbor city interactive development,and gives the policy Suggestions aiming at the problems.  相似文献   

13.
The general psychological theory of activity created by L. S. Vygotsky, A. N. Leontev, A. R. Luria, and their disciples has entered a critical phase in its development. An external sign of the advent of this phase is the increased frequency of discussions of the role of the category of activity in building the conceptual apparatus of psychology. One hears ever more insistently the idea that the category of activity is threatening to become a kind of monster, ready to devour all other psychological concepts [4,14,37,45]A.n internal sign of the advent of this critical phase in the development of the theory of activity is the discrepancy between the tremendous amount of factual material accumulated in the various special areas of psychology in which the theory of activity plays a special role and the initial principles of this theory, formulated very early, when it was just being developed. As a result, a paradox has emerged: a theory engendered by the exigencies of practice is beginning to be perceived as a theory independent of practice. A critical phase in the development of any theory, like a crisis in the development of the life of a child, means the beginning of a new stage in its existence. For such a critical phase to occur, at least the following steps are, I think, necessary. The first step is enumerating the original principles of the theory of activity. The second involves an analysis, through the prism of these original principles, of all the factual material accumulated in the special areas of psychology and in general psychology. This analysis will overcome the discrepancy between the key principles of the theory of activity and the factual material, and will also help to refine and modify those principles. Finally, the third stage is the development of prospects for basic and applied research, i.e., defining the area for the most immediate development of a psychology built on the basis of a general psychological theory of activity.  相似文献   

14.
The work of prominent Russian biologist Alexander Gavrilovich Gurwitsch (1874–1954) on the theory of organism development are reviewed. Alexander Gurwitsch introduced the concept of embryonic (morphogenetic, biological, and cellular) field and proposed several revisions of it from 1912 to 1944. Although neither of them can be considered as a final theory of development, his the persistent search for the invariant law that allows the shape (spatial structure) to be proposed for each next developmental stage from the previous shape is of imperishable methodological interest. Alexander Gurwitsch anticipated many ideas of the future theory of self-organization. His theoretical constructions are explicit and experiment-oriented but absolutely not esoteric. They represent a highly important and original contribution to theoretical biology and are an essential step to further development of the ontogenetic theory.  相似文献   

15.
The present state of the theory of activity (by which we mean the concept developed by Leont'ev and his school) undoubtedly deserves serious discussion. Such a discussion must not be reduced, as often happens, to a critique of this theory by representatives of other schools and currents in psychology that are based on different theoretical positions (i.e., to a criticism from without), on the one hand, or to an unconditional acceptance of all of its postulates by proponents of this theory, on the other. In my view, the kind of critique of this theory that is most relevant and acutely necessary in terms of both its prospects of development and the extent to which its perceptions accord with other psychological currents is of another sort, namely, a critique from within, by which I mean analysis of its own laws, of the internal logic of development of the theory, and of its internal contradictions, which define its present status and the dynamics of its development. Such an analysis should enable us to stimulate more effectively the internal mechanism of development and self-development of the theory of activity and ensure a transition from a period of stagnation that has produced nothing of note to a progressive evolution of its content and its explanatory power.  相似文献   

16.
Belousov LV 《Ontogenez》2008,39(5):379-389
The work of prominent Russian biologist Alexander Gavrilovich Gurwitsch (1874-1954) on the theory of organism development are reviewed. Alexander Gurwitsch introduced the concept of embryonic (morphogenetic, biological, and cellular) field and proposed several revisions of it from 1912 to 1944. Although neither of them can be considered as a final theory of development, his the persistent search for the invariant law that allows the shape (spatial structure) to be proposed for each next developmental stage from the previous shape is of imperishable methodological interest. Alexander Gurwitsch anticipated many ideas of the future theory of self-organization. His theoretical constructions are explicit and experiment-oriented but absolutely not esoteric. They represent a highly important and original contribution to theoretical biology and are an essential step to further development of the ontogenetic theory.  相似文献   

17.
Research carried outby the great Russian scholar I. M. Sechenov has significantly contributed to development of aviation physiology, medicine and psychology. His fundamental works consisted of discovery of the constancy of alveolar air composition theory, study of interactions of analyzers systems in solving the problem of human spatial orientation under flight conditions, development of a nervous theory of fatigue. Creative development of ideas by I. M. Sechenov allowed enhancing the efficiency of performing and safety of aviation and space flights.  相似文献   

18.
Fuzzy systems vegetation theory is a comprehensive framework for the expression of vegetation theory and conceptual models, as well as the development of vegetation analyses. It is applicable to vegetation/environment relations, vegetation dynamics, and the effects of environmental dynamics on vegetation composition. Fuzzy systems vegetation theory is a fuzzy set generalization of dynamical systems theory and incorporates a formal logic and mathematics. This paper presents the elements of fuzzy systems vegetation theory and discusses the relationship of the fuzzy systems theory to the geometric concepts generally employed in vegetation theory.  相似文献   

19.
系统总结了城市暴雨灾害的特征和诱因,建立了高密度中心城区暴雨防灾规划体系,根据中心城区特征提出了基于生态安全理念的土地效能优化、基于绿道理论的绿地空间规划、基于低影响理论的暴雨调节系统、结合地下空间开发的暴雨管网建设等常态暴雨防灾策略,探索了基于灾时应急思维的暴雨防灾策略以及法律规范、技术条件、财政投入等暴雨防灾支撑策略,力图有效指导中心城区的生态安全和可持续发展。  相似文献   

20.
That cationic proteins might be factors on the antimicrobial defenses of mammalian hosts and are apparently associated with the cytoplasmic granules of phagocytic leukocytes first became evident on the late nineteenth century. It remained, however, for development of sophisticated microanalytic techniques in microbiology, cell biology and protein biochemistry to place these hypotheses in the realm of established theory. This article is a brief summary of singificant steps in the development of this theory. It also attempts to outline the firmly established scope and significance of these developments both for the theory of immunity to infection in the different phyla and for the now global quest for new antibiotics.  相似文献   

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