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1.
The late 19th century was the beginning of bacterial taxonomy and bacteria were classified on the basis of phenotypic markers. The distinction of prokaryotes and eukaryotes was introduced in the 1960s. Numerical taxonomy improved phenotypic identification but provided little information on the phylogenetic relationships of prokaryotes. Later on, chemotaxonomic and genotypic methods were widely used for a more satisfactory classification. Archaea were first classified as a separate group of prokaryotes in 1977. The current classification of Bacteria and Archaea is based on an operational-based model, the so-called polyphasic approach, comprised of phenotypic, chemotaxonomic and genotypic data, as well as phylogenetic information. The provisional status Candidatus has been established for describing uncultured prokaryotic cells for which their phylogenetic relationship has been determined and their authenticity revealed by in situ probing. 相似文献
2.
Bérangère Tissot Alessio Ceroni Maria Panico Antonietta Capone Anne Dell Howard R. Morris 《FEBS letters》2009,583(11):1728-8262
This invited paper reviews the study of protein glycosylation, commonly known as glycoproteomics, beginning with the origins of the subject area in the early 1970s shortly after mass spectrometry was first applied to protein sequencing. We go on to describe current analytical approaches to glycoproteomic analyses, with exemplar projects presented in the form of the complex story of human glycodelin and the characterisation of blood group H eptitopes on the O-glycans of gp273 from Unio elongatulus. Finally, we present an update on the latest progress in the field of automated and semi-automated interpretation and annotation of these data in the form of GlycoWorkBench, a powerful informatics tool that provides valuable assistance in unravelling the complexities of glycoproteomic studies. 相似文献
3.
Michael J. A. Simpson Donald F. Macintosh John B. Cloughley Angus E. Stuart 《Economic botany》1996,50(1):122-129
The development ofM. gale oil as an insect repellent has created a requirement for cultivation of the plant. Botanical evidence indicates thatM. gale is likely to thrive on well—aerated acid peatland and could become a valuable crop on land of low agricultural value. Plant growth would be enhanced by the prevention of grazing and could be combined with softwood forestry since the trees would benefit from soil nitrogen enrichment thanks to the symbiotic association ofM. gale andFrankia. The economics of oil production would be improved if additional compounds of value such as pharmacologically active fiavonoids could be extracted from the by-products. 相似文献
4.
Dennis Christensen Else Marie Agger Lars Vibe Andreasen Daniel Kirby Peter Andersen 《Journal of liposome research》2013,23(1):2-11
The use of liposomes as vaccine adjuvants has been investigated extensively over the last few decades. In particular, cationic liposomal adjuvants have drawn attention, with dimethyldioctadecylammonium (DDA) liposomes as a prominent candidate. However, cationic liposomes are, in general, not sufficiently immunostimulatory, which is why the combination of liposomes with immunostimulators has arisen as a strategy in the development of novel adjuvant systems in recent years. One such adjuvant system is CAF01. In this review, we summarize the immunological properties making CAF01 a promising versatile adjuvant system, which was developed to mediate protection against tuberculosis (TB) but, in addition, has shown promising protective efficacy against other infectious diseases requiring different immunological profiles. Further, we describe the stabilization properties that make CAF01 suitable in vaccine formulation for the developing world, which in addition to vaccine efficacy, are important prerequisites for any novel TB vaccine to reach global implementation. The encouraging nonclinical data led to a preclinical vaccine toxicology study of the TB model vaccine, Ag85B-ESAT-6/CAF01, that concluded that CAF01 has a satisfactory safety profile to advance the vaccine into phase I clinical trials, which are scheduled to start in 2009. 相似文献
5.
Wei Wang Mary Ann Knovich Lan G. Coffman Frank M. Torti Suzy V. Torti 《Biochimica et Biophysica Acta (BBA)/General Subjects》2010
Background
Serum ferritin was discovered in the 1930s, and was developed as a clinical test in the 1970s. Many diseases are associated with iron overload or iron deficiency. Serum ferritin is widely used in diagnosing and monitoring these diseases.Scope of review
In this chapter, we discuss the role of serum ferritin in physiological and pathological processes and its use as a clinical tool.Major conclusions
Although many aspects of the fundamental biology of serum ferritin remain surprisingly unclear, a growing number of roles have been attributed to extracellular ferritin, including newly described roles in iron delivery, angiogenesis, inflammation, immunity, signaling and cancer.General significance
Serum ferritin remains a clinically useful tool. Further studies on the biology of this protein may provide new biological insights. 相似文献6.
The paper tries to set right certain ideas about the history of evolutionary developmental biology. The main point is, that
we had to enface the dominance of a comparative approach towards evolutionary developmental biology before 1900, which even
later on was effective in Russia, for example, till the 1930s. The problem of the experimentalist approach set against this
tradition was and is that there is no concept of gestalt that may allow to integrate the former comparative views and the
modern mechanistic interpretations. We argue, that it would be wrong just to describe the comparative tradition as being outdated,
as it may allow to get the framework for a dynamical concept of Gestalt that may integrate the ideas of morphogenesis and pattern formation worked out in evo-devo recently. 相似文献
7.
Classification of vegetation: Past,present and future 总被引:1,自引:0,他引:1
Ladislav Mucina 《植被学杂志》1997,8(6):751-760
Abstract. This paper is a report on the past, status-quo and perspectives of vegetation classification, still a major occupation of many vegetation scientists. The history of vegetation classification is discussed against a background of several controversial issues such as the problem of continuum vs. discontinuum, naturalness vs. arbitrariness of the nature of plant communities, universality vs. ad hoc character of syntaxonomic schemes, as well as classical versus numerical approaches to data analysis for classification purposes. The development of the methodology of vegetation science and the present image of vegetation classification is documented by a bibliometric analysis of the publication record of four majorjournals: Journal of Vegetation Science, Vegetatio, Phytocoenologia and Tuexenia. This analysis revealed a persisting controversy between traditional and numerical approaches to vegetation classification. A series of important changes in vegetation science (foundation of new journals, change of editorial policy by the established, important meetings) punctuate a period called the ‘Innovation period’. Several trends in the development of methods of vegetation systematics are summarized under the headings formalism, pluralism, functionalism, pragmatism and indeterminism. Some new features, such as the development and improvement of numerical tools, use of large data banks and attempts to summarize the theory of vegetation classification are discussed. The new growth-form system of Barkman initiated a revival of physiognomy-based vegetation classification. Within this framework the use of the character-type concept and the development of new numerical methods for studying the hierarchical structure of character-set types seems to be a promising approach. The achievements of population biology and ecophysiology have affected vegetation science by emphasizing the functionality of species within plant communities. The use of guilds and other functional groups has experienced an increasing interest from vegetation scientists. Applied in vegetation science, fuzzy-set theory has bridged the techniques of classification and ordination of plant communities. 相似文献
8.
9.
Testing for genetically modified organisms (GMOs): Past, present and future perspectives 总被引:6,自引:0,他引:6
This paper presents an overview of GMO testing methodologies and how these have evolved and may evolve in the next decade. Challenges and limitations for the application of the test methods as well as to the interpretation of results produced with the methods are highlighted and discussed, bearing in mind the various interests and competences of the involved stakeholders. To better understand the suitability and limitations of detection methodologies the evolution of transformation processes for creation of GMOs is briefly reviewed. 相似文献
10.
Iman F Abou-El-Naga 《Journal of biosciences》2013,38(3):665-672
The African species of Biomphalaria appeared as a result of the relatively recent west-to-east trans-Atlantic dispersal of the Biomphalaria glabrata-like taxon. In Egypt, Biomphalaria alexandrina is the intermediate host for Schistosoma mansoni. Biomphalaria alexandrina originated in the area between Alexandria and Rosetta and has historically been confined to the Nile Delta. Schistosoma mansoni reached Egypt via infected slaves and baboons from the Land of Punt through migrations that occurred as early as the Vth Dynasty. The suggestion of the presence of Schistosoma mansoni infection in Lower Egypt during Pharaonic times is discussed despite the fact that that there is no evidence of such infection in Egyptian mummies. It is only recently that Biomphalaria alexandrina colonized the Egyptian Nile from the Delta to Lake Nasser. This change was likely due to the construction of huge water projects, the development of new water resources essential for land reclamation projects and the movement of refugees from the Suez Canal zone to the Delta and vice versa. The situation with respect to Biomphalaria in Egypt has become complicated in recent years by the detection of Biomphalaria glabrata and a hybrid between both species; however, follow-up studies have demonstrated the disappearance of such species within Egypt. The National Schistosoma Control Program has made great strides with respect to the eradication of schistosoma; however, there has unfortunately been a reemergence of Schistosoma mansoni resistant to praziquantel. There are numerous factors that may influence the prevalence of snails in Egypt, including the construction of water projects, the increase in reclaimed areas, global climate change and pollution. Thus, continued field studies in addition to the cooperation of several scientists are needed to obtain an accurate representation of the status of this species. In addition, the determination of the genome sequence for Biomphalaria alexandrina and the use of modern technology will allow for the study of the host–parasite relationship at a molecular level. 相似文献
11.
Devra G. Kleiman 《Zoo biology》1992,11(5):301-312
This paper reviews the historical emphases in zoo behavioral research and the contribution of these studies to animal management and to advancement in the behavioral sciences. Some examples are provided from research conducted at the National Zoological Park and elsewhere. The potential for doing behavior studies of excellence in zoos and aquariums has become more complicated in recent years by 1) changes in the aims and objectives of modern zoological parks, especially the increasing emphasis on conservation, 2) changes in focus in the science of animal behavior itself, and 3) the tendency of trained behaviorists to assume positions as curators and directors without time for research. These issues represent challenges to be overcome so that zoos can continue to be important sites for the study of animal behavior and contribute to the science of animal management and conservation, as well as the advancement of theory in biology. © 1992 Wiley-Liss, Inc. 相似文献
12.
Dyckia pseudococcinea L.B.Sm. is endemic to the restingas of Maricá, State of Rio de Janeiro, in southeastern Brazil. However, since this area is under intense ecological stress, D. pseudococcinea is considered an endangered plant species. An important step toward the conservation of this species is establishing the developmental stage most favorable to in vitro propagation. Accordingly, the present study analyzed the androecium to establish the developmental stages of anthers, emphasizing anther wall development, androsporogenesis and androgametogenesis. The relationships between the size of flowers and anthers were also studied. Anther wall development follows the basic-type, while the tapetum, which is originated from the subepidermal layer (inner secondary parietal layer 2 and archesporial initials), follows the secretory-type. Androsporogenesis is successive and originates isobilateral and decussate tetrads. The oblate and monosulcate pollen grains exhibit microreticulate exine and are dispersed at the bicellular stage. At the vacuolated stage, the androspore (microspore) is still proliferating and not yet completely differentiated. Therefore, since the androspore has not yet lost its embryonic capacity, we suggest the preferential use of this developmental stage, which is present in flower buds 6.4–7.1 mm in length, in conservation protocols focused on the androgenesis of D. pseudococcinea. 相似文献
13.
14.
The global nitrogen cycle: Past, present and future 总被引:3,自引:0,他引:3
James N.Galloway 《中国科学:生命科学英文版》2005,48(Z2)
Food and energy production converts N2 to reactive N species that cascade through environmental reservoirs and in the process impact human and ecosystem health. This presentation will examine the impact of increased N mobilization on the global N cycle by contrasting N distribution in the late-19th century with those of the late-20th century. The presentation will give a general overview of regional differences and will conclude with a projection of the global N cycle for 2050. 相似文献
15.
James N. Galloway 《中国科学C辑(英文版)》2005,48(Z2)
Food and energy production converts N2 to reactive N species that cascade through environmental reservoirs and in the process impact human and ecosystem health. This presentation will examine the impact of increased N mobilization on the global N cycle by contrasting N distribution in the late-19th century with those of the late-20th century. The presentation will give a general overview of regional differences and will conclude with a projection of the global N cycle for 2050. 相似文献
16.
Susanna KP Lau Siddharth Sridhar Chi-Chun Ho Wang-Ngai Chow Kim-Chung Lee Ching-Wan Lam Kwok-Yung Yuen Patrick CY Woo 《Experimental biology and medicine (Maywood, N.J.)》2015,240(6):742-751
Melioidosis is an emerging, potentially fatal disease caused by Burkholderia pseudomallei, which requires prolonged antibiotic treatment to prevent disease relapse. However, difficulties in laboratory diagnosis of melioidosis may delay treatment and affect disease outcomes. Isolation of B. pseudomallei from clinical specimens has been improved with the use of selective media. However, even with positive cultures, identification of B. pseudomallei can be difficult in clinical microbiology laboratories, especially in non-endemic areas where clinical suspicion is low. Commercial identification systems may fail to distinguish between B. pseudomallei and closely related species such as Burkholderia thailandensis. Genotypic identification of suspected isolates can be achieved by sequencing of gene targets such as groEL which offer higher discriminative power than 16S rRNA. Specific PCR-based identification of B. pseudomallei has also been developed using B. pseudomallei-specific gene targets such as Type III secretion system and Tat-domain protein. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry, a revolutionary technique for pathogen identification, has been shown to be potentially useful for rapid identification of B. pseudomallei, although existing databases require optimization by adding reference spectra for B. pseudomallei. Despite these advances in bacterial identification, diagnostic problems encountered in culture-negative cases remain largely unresolved. Although various serological tests have been developed, they are generally unstandardized “in house” assays and have low sensitivities and specificities. Although specific PCR assays have been applied to direct clinical and environmental specimens, the sensitivities for diagnosis remain to be evaluated. Metabolomics is an uprising tool for studying infectious diseases and may offer a novel approach for exploring potential diagnostic biomarkers. The metabolomics profiles of B. pseudomallei culture supernatants can be potentially distinguished from those of related bacterial species including B. thailandensis. Further studies using bacterial cultures and direct patient samples are required to evaluate the potential of metabolomics for improving diagnosis of melioidosis. 相似文献
17.
Since 1928, human fetal tissues and stem cells have been used worldwide to treat various conditions. Although the transplantation of the fetal midbrain substantia nigra and dopaminergic neurons in patients suffering from Parkinson's disease is particularly noteworthy, the history of other types of grafts, such as those of the fetal liver, thymus, and pancreas, should be addressed as there are many lessons to be learnt for future stem cell transplantation. This report describes previous practices and complications that led to current clinical trials of isolated fetal stem cells and embryonic stem(ES) cells. Moreover, strategies for transplantation are considered, with a particular focus on donor cells, cell processing, and the therapeutic cell niche, in addition to ethical issues associated with fetal origin. With the advent of autologous induced pluripotent stem cells and ES cells, clinical dependence on fetal transplantation is expected to gradually decline due to lasting ethical controversies, despite landmark achievements. 相似文献
18.
The brief tenure of environmental enrichment has been influenced both directly and indirectly by the field of psychology, from the work of B.F. Skinner to that of Hal Markowitz. Research on enrichment supports the supposition that an enriched environment does indeed contribute to a captive animal’s well‐being. Critical elements of effective environmental enrichment are 1) assessing the animal’s natural history, individual history, and exhibit constraints and 2) providing species‐appropriate opportunities, i.e., the animal should have some choices within its environment. This paper presents a historic perspective of environmental enrichment, proposes a broader, more holistic approach to the enrichment of animals in captive environments, and describes a framework or process that will ensure a consistent and self‐sustaining enrichment program. Zoo Biol 20:211–226, 2001. © 2001 Wiley‐Liss, Inc. 相似文献
19.
Nitrate reductase activity (NRA) in different compartments (leaves, inflorescence stalks, flowers and tuberous roots) of Asphodelus aestivus Brot. (Liliaceae) and actual mineral nitrogen (NO3−-N and NH4+-N) in soil surrounding the roots were investigated over one year. Although the highest NRA was found in the leaves, the other plant compartments, such as flowers and tuberous roots, also have nitrate assimilation capacity. High nitrate assimilation capacity under suitable conditions is considered to be a good strategy for development and dominance of this species in Mediterranean environments. There was a seasonal variation in nitrate assimilation in leaves and actual NO3−-N content of soils. Depending on actual nitrate content of soils, nitrate assimilation increased in winter. 相似文献
20.
Across the world there is a prevailing view that freshwater algae are cosmopolitan. The notion has seldom been tested and
is unlikely to be true in genetic terms. Nonetheless, some morphospecies of several groups of algae do have a worldwide distribution.
Others have restricted distributions and may be regarded as endemic to a region. However there is always the possibility that
they will be discovered in far away places. Australia has a rather large element of endemicity in its algal flora. From the
early days of Australian phycology many new genera and species of freshwater algae have been described. Some are of such distinctive
appearance or novelty as to be regarded as ‘flagship’ taxa. There is little doubt about their endemicity and their existence
increases the probability of less-distinguished species also being endemic. The degree of endemicity is probably masked by
the ‘force-fitting’ of European names to Australian species.
Some Australian endemics are robust and are widely distributed in a variety of types of water body. Others, the frail endemics,
the ones of greatest novelty and phylogenetic significance, have a very restricted range with their strongholds in dystrophic
coastal lagoons where tracts or remnant patches of native vegetation survive. Their survival and the conservation of their
biodiversity depends on recognition of the significance of coastal lagoons and swamps. 相似文献