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1.
The taxonomic, trophic, and quantitative structures of the macrozoobenthos in the deepwater part of the Gorky Reservoir were studied in autumn 2005. A total of 51 species of bottom macroinvertebrates were revealed, most of which were represented by chironomids, oligochaetes, and mollusks. The detriti-vores—swallowers dominated in number; phytodetritivores—filtrators + gatherers dominated in biomass. An analysis of the long-term dynamics of the macrozoob enthos structure in the Gorky Reservoir revealed that the average abundance and biomass decreased at the beginning of the XXI century.  相似文献   

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The latest analysis of the state of dendrological studies in Russia was carried out by V. N. Sukachev in 1921 and published in the Proceedings of the All-Russian Forest Conference. Over the past 83 years, many new botanic gardens have been created (in Russia they are over 80), and dendrological studies in many biological institutes and universities have been enlarged. Dendrologists have been faced with new challenges related to the development of eastern regions of Russia and the need for a comprehensive study and conservation of the gene pool of woody plants in nature and culture. The present paper deals with problems that should be addressed in the first place and in the longer term. Particular attention is paid to the introduction of woody plants from different botanical-geographical areas of Eurasia and North America to Russia, and modern notions of the state of the native woody flora of Siberia and the Far East are analyzed in connection with the solution of the global problem of studying and conserving the vegetation biodiversity of Russia. The paper is concluded with a list of the main challenges facing dendrologists which, in the author’s opinion, should be taken into account when planning dendrological studies in various regions of Russia.  相似文献   

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A new definition of sexual dimorphism is required. The divergent biology of the sexes is still largely ignored, overshadowed by sociocultural considerations and confined to its hormonal organizational and activational effects, while the genes unequally expressed by the sex chromosomes play an important role much earlier, after conception, to set the stage and throughout life. These different components have independent and parallel effects that can interact in a synergistic or antagonistic manner on differentiation and response processes to trigger or erase sex-specific differences. The epigenetic marks and machinery represent the perfect tools to keep the memory of which sex is ours from the very beginning of life. Within the context of the developmental origin of adult health and diseases (DOHaD), owing to their flexibility to the environment, epigenetic marks also represent a support to archive the effects of environments during development, according to the sex of the parent, in a sex-specific mode. In all tissues, including gonads and brain, different trajectories of genes and pathways are used at the basal levels and to modulate/dictate responses according to sex and gender. It is urgent to emphasize the need to take into consideration this new knowledge and to apply less sex-biased approaches in research, medicine and society, to enhance women health and well-being. A critical review and realization of gender-specific social constraints, an indeniably but slowly on-going process, should allow us to "set free our sex biology" while detracting the delusion of hierarchy of the complex mechanisms involved.  相似文献   

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The remarkable anthropological series formed by E. Tamagnini at the Universidade de Coimbra consists of the exhumed human remains from “La Conchada” cemetery, in Coimbra (Northern Portugal). From this collection, only those individuals coming from the different districts of Coimbra, where they also lived and died, were selected for study. The resulting series was made of by 483 individuals: 234 women and 249 men. The personal data sheets indicate that these people died between 1910 and 1938; their professions, age at death and its cause are also noted. They can be considered as a relatively homogeneous group of low socioeconomical level. The study of the three oraltori demonstrated the high frequencies of all of them, the absence of sexual dimorphism and only a few statistically significant differences between some of the age classes considered. The possible etiological factors (genetical and/or environmental) are also discussed.  相似文献   

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In many developed countries, isolation of human pharmaceutical proteins from milk of genetically modified animals is currently a priority. One of the first commercial pharmaceuticals obtained from the milk of transgenic goats, an anticoagulant antithrombin III, developed by Genzyme Transgenic Corporation, an American biotechnological company, will appear on the pharmaceutical market in the nearest future. In this review, we discuss the role of fundamental science in the development of this field of the pharmaceutical industry.  相似文献   

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The situation of cervical cancer prevention in South-East Europe is hardly documented, in spite of the fact that it encloses the most affected countries of Europe. We estimated the number of cases of cervical cancer, the number of deaths from this malignancy and the corresponding rates for 11 countries located in South-East Europe, in the period 2002-2004. Each year, approximately 9,000 women develop cervical cancer and about 4,600 die from the disease in this subcontinent. The most affected country is Romania with almost 3,500 cases and more than 2,000 deaths per year High world-age standardised mortality rates (> 7.5 [expressed per 100,000 women-years]) are observed in 7 countries: FYROM (7.6), Moldova (7.8), Bulgaria (8.0), Bosnia & Herzegovina (8.0), Albania (9.8), Serbia & Montenegro (10.1) and Romania (13.0). A matter of concern is the increasing mortality rate, in younger women, in the countries with the highest burden of cervical cancer. Thus, appropriate cervical cancer prevention programmes should be set up without delay in this part of Europe.  相似文献   

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Traditionally, studies of scientific productivity are biased in two ways: they are based on Current Contents, an index centered in British and American journals, and they seldom correct for population size, ignoring the relative effort that each society places in research. We studied national productivity for biology using a more representative index, the Biological Abstracts, and analyzed both total and relative productivity. English dominates biological publications with 87% (no other individual language reaches 2%). If the USA is considered a region by itself, it occupies the first place in per capita production of biology papers, with at least twice the productivity of either Asia or Europe. Canada, Oceania and Latin America occupy an intermediate position. The global output of scientific papers is dominated by Europe, USA. Japan, Canada, China and India. When corrected for population size, the countries with the greatest productivity of biology papers are the Nordic nations, Israel, Switzerland, Netherlands, Australia, Saint Lucia and Montserrat. The predominance of English as the language of biological research found in this study shows a continuation of the trend initiated around the year 1900. The large relative productivity of the USA reflects the importance that American society gives to science as the basis for technological and economic development, but the USA's share of total scientific output has decreased from 44% in 1983 to 34% in 2002, while there is a greater growth of science in India, Japan and Latin America, among others. The increasing share obtained by China and India may reflect a recent change in attitude towards funding science. The leadership of Nordic nations, Israel, Switzerland, Netherlands and Australia can be explained by cultural attitude. Apparently, a positive trend is emerging in Latin America, where Chile improved its ranking in per capita productivity but Argentina, Costa Rica, Uruguay, Brazil and Cuba fell. Nevertheless, the most productive countries in total number of papers are Brazil, Mexico and Argentina: large countries with a long tradition of funding scientific research.  相似文献   

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Progress of physiology is closely connected with achievements of the adjacent sciences that developed particularly intensively at the end of the XX century. The key role in strategy of physiological investigations is played by study of the nature of regulation of individual processes providing activity of the organism as a whole. By the example of study of renal function there are discussed the issue of integration of its incretory and secretory functions, elucidation of the mechanism of activity of regulatory systems with taking into account the wide diversity of types and subtypes of receptors, interaction of numerous variants of cotransporters, pumps, water and ion channels, which eventually provides the amazing efficiency of the coordinated work of several organs and systems for stabilization of physical-chemical parameters of the internal environment. Development of physiology is of importance for progress of natural science and clinical medicine, as its achievements facilitate discovery of mechanisms of physiological functions, elucidation of defect of the locus underlying dysfunction.  相似文献   

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Twenty-five introduced fish species are established in Spanish fresh waters. Most of the introductions took place after 1900, with a significant exponential increase during the second half of the 20th century (15 species introduced from 1949). Major stocking efforts in Spanish waters have been suspended, but recently some species have been released by anglers or are suspected to be escapes from fish farms. Stream regulation is considered to be one of the main negative factors affecting river ecosystems in Spain, but many of the aliens adapt well to these altered habitats. Competition between native and exotic fishes is certain to occur to some degree, but there is little quantitative information. Fish conservation and fishery management must not be based on the 'introduce anything' sentiment that has developed over more than a century. Information, education and public awareness are critical components of any effort to prevent the spread of introduced fish species.  相似文献   

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The structure of macrozoobenthos has been studied in the deep-water part of the Rybinsk Reservoir. A total of 73 species of bottom macroinvertebrates have been recorded, the majority of which are mollusks, oligochaetes, and chironomids. The macrozoobenthos on gray silts of channel parts of the reservoir was the richest in taxonomic composition and quantitative abundance. The maximum number of species has been recorded in the former mouth of the Mologa River, and the highest abundance of macrozoobenthos has been recorded near the village of Breitovo in June. Most of the macrozoobenthos is made up of oligochaetes and chironomid larvae; midge larvae dominate by biomass. Compared to the end of the 20th century, changes in the taxonomic composition and in dominating species of macrozoobenthos are observed.  相似文献   

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The biological standard of living in Central Italy at the beginning of the 19th century is analyzed using newly collected data on the height of recruits in the army of the Papal States. The results reveal a decline in height for the cohorts born under French rule (1796–1815). Although this trend was common to many parts of Europe, the estimated magnitude of the decline suggests a worsening of the biological standard of living of the working classes in the Papal States even relative to that of other countries. Despite the differences in the economic systems within the Papal States, no significant geographical variation in height has been found: even the most dynamic and advanced regions experienced a dramatic height decline. Mortality also increased during the period under consideration.  相似文献   

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Systematics as regarded is a purely theoretical domain of biology, and its product, system, as a specific biological theory, or a topologo-genetic model of the biota. Linnaeus was the first to introduce the idea of system and the systematic approach into the natural history. The advent of evolutionism brought new meaning to the old term "affinity", so Linnaeus' slogan of natural system got new life, and Linnaeus taxonomy assimilated the evolutionary ideology quite naturally and much easier than many other departments of biology. The difference between natural and artificial systems is remaining, and it is in their goals, as formulated by Linnaeus: heuristic of the former and cataloguing of the latter. Linnaeus' clairvoyance discovered the existence of an infrageneric level of genetic integration provable by naturalists' experience. He chose for it the designation of "species" and laid it down as primary, basic unit of his system. This is plainly evident from his own writings; the story about Linnaean species being products of a logical division of genera is a pure fiction. Modern populational model of species, by 3 important criteria, appears to be more akin to the Linneaean one than to the ideas of Lamarckism and early Darwinism. Systematic approach focuses rather on the interrelations among elements and their relative position, then on the properties and qualities of separately treated individual elements. In the development of systematics the aspect of "nexification" (study of connections) has been continuously gaining attention especially regarding the nomenclature where connotation has been totally forced out by denotation.  相似文献   

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Human reproduction is a biological phenomenon, however, sociocultural factors such as marital status influence pregnancy outcome and reproductive success. In the present study the impact of maternal marital status on pregnancy outcome was tested for all births, which had taken place in Austria between 1999 and 2004, which met the following criteria: single births, nulliparity, mothers older than 19 years (n = 179 830). The rate of preterm delivery (< 37 beginning weeks of gestation) and rate of low birth weight (< 2500 g) among term births were significantly higher among unmarried mothers in comparison to married mothers. Additionally the newborns of unmarried mothers were significantly lighter and shorter than those of married mothers. This was especially true of immigrant mothers. No significant differences between married and unmarried mothers were found regarding mode of delivery. Even at the beginning of the 21st century unmarried status represents an important stress factor for pregnant women.  相似文献   

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The analysis of the geographical distribution of surnames (whose transmission in the European societies is similar to that of the Y chromosome) allows to study in an exhaustive way the spatial and temporal human population structure and the influence of environmental variations on this structure. The genetic structure of the Ardèche county was analysed through a study of the surname characteristics (diversity, frequency, geographical dispersion, etc.) of individuals born between 1891 and 1915. The estimation of the intra-community average consanguinity and the inter-district genetic relationships reveals a clear differentiation between populations of the mountainous part (geographically isolated, highly inbred) and those of the Rh?ne valley (less isolated, weakly inbred). As predicted by the isolation by distance model, inter-population coefficients of kinship decreases as distance increases, confirming the presence of a spatial structure, characterized by neighborhood exchange and resulting from former migratory flow.  相似文献   

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