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1.
N P Dubinin 《Genetika》1992,28(1):38-51
The paper is devoted to A.S. Serebrovski?'s studies on induced mutagenesis. His first publication on X-ray induction of mutations in Drosophila appeared in 1928; this became a classical work and entered the golden fund of modern radiation genetics. Investigations of the scientists in the A.S. Serebrovski?'s laboratory as will as his own works on the analysis of radiation mutations at the achaete-scute complex have led to the development of the teaching about gene subdivision and made it possible to draw up a linear array of a gene from elementary subgenes, which have laid down the foundations of the modern molecular-genetic theory of gene.  相似文献   

2.
Synthesis and Selection: Wynne-Edwards' Challenge to David Lack   总被引:4,自引:2,他引:2  
David Lack of Oxford Universityand V.C. Wynne-Edwards of Aberdeen Universitywere renowned ornithologists with contrastingviews of the modern synthesis which deeplyinfluenced their interpretation and explanationof bird behavior. In the 1950's and 60's Lackbecame the chief advocate of neo-Darwinism withrespect to avian ecology, while Wynne-Edwardsdeveloped his theory of group selection. Lack's position was consistent with thedeveloping focus on individual leveladaptation, which was a core concept of themodern synthesis. Alternatively, Wynne-Edwardsviewed the emphasis on populations as the mostimportant development provided by the modernsynthesis. In this paper, I present thedevelopment of these two positions and tracetheir roots in the literature of the synthesis.Through an analysis of Lack's 1966 critique ofWynne-Edwards I conclude that Wynne-Edwardswas, in many ways, justified in his pursuit ofgroup level explanations.  相似文献   

3.
This invited presentation is intended to cover clinical developments in the evolution of assisted reproductive technology (ART), a process which was attempted during the 1940's and 50's and culminated in the first fruition in 1978. The first in vitro fertilisation (IVF) child ensued following the partnership by a scientist with a focussed ambition (Nobel laureate Robert Edwards) joining with the gynaecologist who introduced laparoscopy to Britain in the late 60's (Patrick Steptoe). My journey commenced in 1976 as a clinician who became immersed in the embryological and endocrinological science, whence most progress in ART emanates, and continued into a medical directorship position from which this personal view is documented. Several clinical advances have been important developments in the understanding and management of sub-fertile patients. However evolution of the various laboratory sciences has been the major key essential to meeting both the immediate as well as the long-term needs for human reproduction. The future requires a much better understanding and control over gametogenesis and a laboratory process which much more closely duplicates intrinsic reproductive physiology, avoiding gamete and embryo exposure to the atmosphere.This invited presentation is intended to cover clinical developments in the evolution of assisted reproductive technology (ART), a process which was attempted during the 1940's and 50's and culminated in the first fruition in 1978. The first in vitro fertilisation (IVF) child ensued following the partnership by a scientist with a focussed ambition (Nobel laureate Robert Edwards) joining with the gynaecologist who introduced laparoscopy to Britain in the late 60's (Patrick Steptoe). My journey commenced in 1976 as a clinician who became immersed in the embryological and endocrinological science, whence most progress in ART emanates, and continued into a medical directorship position from which this personal view is documented. Several clinical advances have been important developments in the understanding and management of sub-fertile patients. However evolution of the various laboratory sciences has been the major key essential to meeting both the immediate as well as the long-term needs for human reproduction. The future requires a much better understanding and control over gametogenesis and a laboratory process which much more closely duplicates intrinsic reproductive physiology, avoiding gamete and embryo exposure to the atmosphere.  相似文献   

4.
Ingham P 《Current biology : CB》2003,13(15):R583-R584
Philip Ingham grew up in Liverpool and graduated from Cambridge University in 1977. He did his D.Phil in Developmental Genetics at Sussex University and postdoctoral work in Strasbourg, France before joining the laboratory of David Ish-Horowicz at the ICRF Mill Hill Laboratories. Here he applied the emerging technique of tissue in situ hybridisation to the analysis of the Drosophila segmentation genes. After a short spell at the MRC Laboratory of Molecular Biology in Cambridge, he rejoined the ICRF as a Research Scientist at the Developmental Biology Unit in Oxford. His group pioneered the analysis of the Hedgehog signalling pathway in Drosophila and in collaboration with the labs of Andy McMahon and Cliff Tabin at Harvard University, discovered the Hedgehog gene family in vertebrates. In 1996 he was appointed Professor of Developmental Genetics at the University of Sheffield where he has established the Centre for Developmental Genetics.  相似文献   

5.
Paul Bert worked with Claude Bernard, one of the leading physiologists of the 19th century. In his laboratory at the Collège de France in Paris, Paul Bert carried out fascinating experiments in particular on respiratory processes, leading him to publish "La pression barométrique" in 1878. In this book are recalled his discovery of oxygen pressure decrease with altitude, divers diseases, the improved safety protocols in hyperbaric conditions, and the first development of gas anaesthetics for surgery. He was the third President of the Société de Biologie. Paul Bert was also a politician with strong convictions. Minister of Education under Gambetta's short term government, he initiated the fight for social equality and secular education and became one of the most prestigious figures of the developing socialist party. He received many distinctions and was given a state funeral.  相似文献   

6.
The Bernard Distinguished Lecturers are individuals who have a history of experience and expertise in teaching that impacts multiple levels of health science education. Dr. Joel Michael more than meets these criteria. Joel earned a BS in biology from CalTech and a PhD in physiology from MIT following which he vigorously pursued his fascination with the mammalian central nervous system under continuous National Institutes of Health funding for a 15-yr period. At the same time, he became increasingly involved in teaching physiology, with the computer being his bridge between laboratory science and classroom teaching. Soon after incorporating computers into his laboratory, he began developing computer-based learning resources for his students. Observing students using these resources to solve problems led to an interest in the learning process itself. This in turn led to a research and development program, funded by the Office of Naval Research (ONR), that applied artificial intelligence to develop smart computer tutors. The impact of problem solving on student learning became the defining theme of National Science Foundation (NSF)-supported research in health science education that gradually moved all of Dr. Michael's academic efforts from neurophysiology to physiology education by the early 1980's. More recently, Joel has been instrumental in developing and maintaining the Physiology Education Research Consortium, a group of physiology teachers from around the nation who collaborate on diverse projects designed to enhance learning of the life sciences. In addition to research in education and learning science, Dr. Michael has devoted much of his time to helping physiology teachers adopt modern approaches to helping students learn. He has organized and presented faculty development workshops at many national and international venues. The topics for these workshops have included computer-based education, active learning, problem-based learning, and the use of general models in teaching physiology.  相似文献   

7.
Pavlov's discovery of experiment neurosis was serendipitous, yet it was made under the influence of Breuer and Freud's case of Anna O. In 1914, Pavlov's disciple N. R. Shenger-Krestovnikova, exploring the limits of visual discrimination in dogs, noticed that when the discrimination was difficult, the dogs' behavior became disorganized. Pavlov drew an analogy between the condition of Shenger-Krestovnikova's dogs and their disorganized behavior with Anna O.'s situation and her neurotic reaction. Pavlov concluded that he had demonstrated in the laboratory the elements of neurosis in animals and human alike. Schilder's criticism of his position, his later study of human neuroses in clinical settings, and the views of Janet may have induced Pavlov to differentiate between animal and human neuroses.  相似文献   

8.
The 2004 Federation of European Biochemical Societies (FEBS) Congress in Warsaw marks the 40th Anniversary of FEBS. To celebrate this event, the Executive Committee decided to publish a memoir, which chronicles the foundation of FEBS and its early development as well as presents an overview of FEBS activities and contributions that support the ever growing disciplines of biochemistry, molecular cell biology and molecular biophysics throughout Europe [Forty Years of FEBS Horst Feldmann (Ed.), Blackwell Publishers, Oxford 2003, on behalf of FEBS]. This paper summarizes some of the most important aspects of this compilation.  相似文献   

9.
In Hb Warsaw Val replaces the Phe normally present at the heme contact position beta 42 (CD1). This variant is unstable, and it readily undergoes methemoglobin formation. In DEAE-cellulose chromatography, the variant hemoglobin co-eluted with Hb A; a partially heme-depleted fraction of the variant, representing 5-6% of the total hemoglobin, eluted separately and in pure form. The heme replete form of Hb Warsaw exhibited decreased oxygen affinity with a normal Bohr effect and normal cooperativity and interaction with 2,3-diphosphoglycerate (DPG). The heme-depleted Hb Warsaw had a higher oxygen affinity than that of Hb A, decreased cooperativity and 2,3-DPG interaction, and a very low alkaline Bohr effect. Gel filtration of the heme-depleted form showed it to exist entirely as alpha beta dimers. Globin chain synthesis by Hb Warsaw-containing reticulocytes followed a balanced alpha/beta ratio. In short-term synthesis experiments, a major portion of incorporated radiolabeled L-leucine was recovered from the dimeric, heme-depleted Hb Warsaw fraction, suggesting that subunit association precedes the incorporation of heme into the beta subunits in the post-synthetic assembly of this hemoglobin. Structural analysis of deoxyhemoglobin containing roughly equal proportions of normal and variant beta chains showed that the replacement leaves a cavity next to the heme that is large enough to hold a water molecule, which may account for the instability of Hb Warsaw. The heme and the pyrrol nearest to ValCD1 tilt into the cavity. The resulting increase in the tilt of the proximal histidine relative to the heme plane, coupled with a possible stretching of the Fe-N epsilon bond may account for the low oxygen affinity.  相似文献   

10.
Percentage of the elderly is higher in the Warsaw metropolitan area than that in other parts of Poland. This difference became more pronounced in the eighties. An analysis has shown that considering changes in the population age structure overall mortality rate in the Warsaw metropolitan area tended to decrease. It resulted from the decrease in mortality rate in the youngest (under 30 years) and the oldest population groups (over 74 years). An increase in mortality rate was noted in some subgroups of middle age and an advanced age (up to 74 years). It did not change the general trend, i.e. decrease in overall mortality rate. Mortality rate of males inhabiting Warsaw metropolitan area was lower in nearly all age groups in comparison with indices for the whole country. The same was seen in the groups of the youngest and oldest women. It may be assumed that health conditions favor men over women inhabiting Warsaw metropolitan area in comparison with the values for the whole country.  相似文献   

11.
Mary Esther Gaulden presents a personal summary of the activities of Alexander Hollaender, from his days at the National Institutes of Health to his becoming Director of the Biology Division of the Oak Ridge National Laboratory in 1947. This appealing story deals with many of her reactions to his personality and organizational style. It reflects the atmosphere of science in those days, and her enthusiasm in this vibrant milieu. Next is a brief account by John Jagger of his first meeting with Dr. Hollaender, arrival in Oak Ridge in April 1956, and wedding to Mary Esther six months later at the house of the Hollaenders in Oak Ridge. The third section is an account by Virginia P. White of how she came to Oak Ridge in 1955 and became Dr. Hollaender's Laboratory Administrator. She gives a personal account of the many facets of his managerial style, as well as of the personality of his wife, Henrietta. She also describes one of Hollaender's many avocations, the collection of fossils on Sunday morning hikes in the Cumberland Mountains, accompanied by lab and visiting personnel, and finally comments on the annual research conferences in Gatlinburg TN, for which Hollaender and the lab became very well known, with some closing vignettes on his leadership style.  相似文献   

12.
Despite the tension between the United States and the Soviet Union in the early 1920's, the Rockefeller Foundation and the Rockefeller Institute for Medical Research found ways to assist I.P. Pavlov. In addition to providing scientific literature and financial aid, these institutions and their officers rendered important moral support to the scientific career of Pavlov during his later years. In 1923, as a guest of the Rockefeller Institute, Pavlov visited American scientific laboratories. In 1924, he requested and received a number of books on physiology, and during the 1930's the Foundation helped him to acquire equipment for his Leningrad laboratory.  相似文献   

13.
Interest in the interaction between proteins and polysaccharides in semidilute systems developed in the late 1950's and early 1960's both in the field of matrix biology and in the construction of new separation techniques. The author gives an account of how his work in the 50's on the characterization of a connective tissue polysaccharide, hyaluronan, led him into studies on polysaccharide networks, sieve effects, molecular exclusion, a theory of gel filtration, solubility of proteins and chemical equilibria in polymer solutions, water and protein homeostatis in vivo, and ordered convectional flow in concentrated polymer systems.  相似文献   

14.
Mitchell's formulation of the chemiosmotic theory of oxidative phosphorylation in 1961 lacked any experimental support for its three central postulates. The path by which Mitchell reached this theory is explored. A major factor was the role of Mitchell's philosophical system conceived in his student days at Cambridge. This system appears to have become a tacit influence on his work in the sense that Polanyi understood all knowledge to be generated by an interaction between tacit and explicit knowing. Early in his life Mitchell had evolved a simple philosophy based on fluctoids, fluctids and statids which was developed in a thesis submitted for the z at the University of Cambridge, England. This aspect of his work was rejected by the examiners and became a tacit element in his intellectual development. It is argued from his various publications that this philosophy can be traced as an underlying theme behind much of Mitchell's theoretical writing in the 50's leading, through his notion of vectorial metabolism, to the formulation and amplification of the chemiosmotic theory in the sixties. This philosophy formed the basis for Mitchell of his understanding of biological systems and gave him his unique approach to cell biology. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

15.
We review a model-based approach to estimate local population F(ST) 's that is based on the multinomial-Dirichlet distribution, the so-called F-model. As opposed to the standard method of estimating a single F(ST) value, this approach takes into account the fact that in most if not all realistic situations, local populations differ in their effective sizes and migration rates. Therefore, the use of this approach can help better describe the genetic structure of populations. Despite this obvious advantage, this method has remained largely underutilized by molecular ecologists. Thus, the objective of this review is to foster its use for studying the genetic structure of metapopulations. We present the derivation of the Bayesian formulation for the estimation of population-specific F(ST) 's based on the multinomial-Dirichlet distribution. We describe several recent applications of the F-model and present the results of a small simulation study that explains how the F-model can help better describe the genetic structure of populations.  相似文献   

16.
《Comptes Rendus Palevol》2002,1(7):649-656
Born on 16 March 1794 in Hamburg as a son of a Huguenot family whose members made big fortune as ship-owners, Ami Boué took his doctor’s degree in medicine in 1817 at the University of Edinburgh. During the following years, he completed his knowledge in the field of natural sciences, especially in Geoscience. In 1830, after having founded, with other scientists, among whom Constant Prévost and Gérard-Paul Deshayes, the Geological Society of France, in which Boué became the first president, he left Paris in 1835 and settled in Vienna. In 1836, 1837 and 1838 he crossed the Balkans. In his masterpiece La Turquie d’Europe (Paris, 1840, four volumes), he published the results of this research. In his study, Ami Boué intended to join the Austrian empire with Turkey by railways. Anyway, Boué’s works concerning the Balkans were fundamental for the future generations of Austrian geoscientists.  相似文献   

17.
The performance of four commercial media, polymyxin-acriflavine-LiCl-ceftazidime-aesculin-mannitol (PALCAM), Oxford, Rapid'L.mono (Bio-Rad, Marne la Coquette, France) and Agar Listeria according to Ottaviani and Agosti (ALOA: AES Laboratoire, Combourg, France; Biolife, Milan, Italy), used to detect and enumerate 176 Belgian strains of Listeria monocytogenes of human and food origin, was evaluated. Four strains showed a low recovery and/or atypical colonies on one or more media. These results showed that a combination of these media, especially alternative media (Rapid'L.mono and/or ALOA) with esculin-containing media (PALCAM and/or Oxford), should therefore be recommended to detect or enumerate atypical strains of L. monocytogenes. In outbreak case investigation for example, incubation of plates should be extended to at least 96 h if no colonies are typical or growth does not appear after 48 h. This is a cost/benefit calculation that should be done in the context of recent listeriosis risk assessments.  相似文献   

18.
A brief account is given of the research that D.I. Arnon did before he ventured into the field of photosynthesis, viz. his work on inorganic plant nutrition in the laboratory of D.R. Hoagland. The connection between the two areas is indicated. In his work on plant nutrition Dr Arnon emphasized the role of specific nutrients and, with P.R. Stout, formulated a definition of essentiality that is used to this day. It is now necessary, however, to take into account elements not meeting their criteria of essentiality, as shown by a consideration of the element silicon.  相似文献   

19.
Summary The contact potential difference at the cell membranein vitro-air interface was measured using the dynamic oondensator method. The potential differences were found to be different for various types of living and dead cells.The authors are indebted to Professor Dr. Kazimierz Dux from the Laboratory of Tumor Biology, M. Sklodowska-Curie Institute of Oncology, Warsaw, for his interest in this work.  相似文献   

20.
Changes in Hickling Broad, since its creation in the 14th or 15th centuries by the flooding of peat diggings, have been deduced from dating and analysis of a sediment core, historical information and current limnological studies. Until the 1930's there was little major change. Increased agricultural land fertilization led to markedly increased organic sedimentation from the 1930's onwards, due to increased growth of submerged macrophytes. Inorganic sedimentation increased concurrently as more powerful pumps were installed to help drain the adjacent fens and marshes.There was no evidence of increased plankton populations during this phase, but epiphytic diatom populations increased. In the mid 1960's the current period of hypereutrophication began. Epiphytic diatom numbers increased markedly and in the early 1970's the previous luxuriant macrophytes became sparse and the water became turbid with phytoplankton. These changes are attributable mainly to increases in the size of a roost of migratory black headed gulls (Larus ridibundus L.) on the lake in autumn and winter.  相似文献   

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