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1.
An examination of Tschermak's two papers of 1900 not only reinforces our conclusion cited in our first paper on Tschermak that he was not a rediscoverer of Mendelism, but also he did not understand Mendel when he had read it. His concept of dominance differed from that of Mendel, and his use of his own concept is inconsistent and contradictory. His discussion of his backcross data indicated that he had no idea of the nature of Mendelian ratios. Nowhere did he develop the ideas of segregation and independent assortment.  相似文献   

2.
The paper reviews the life of Paul Ehrlich and his biomedical accomplishments in immunology, cancer research, and chemotherapy. Ehrlich achieved renown as an organic chemist, histologist, hematologist, immunologist, and pharmacologist. He disliked the formality of school but managed to excel in Latin and mathematics. His role model was an older cousin, Carl Welgert, who became a lifelong friend. Ehrlich studied medicine at Breslau, Strasbourg, Freiburg, and Leipzig, coming under the influence of Wilhelm Waldeyer, Julius Cohnheim, Rudolf Heidenhein, and Ferdinand Cohn. As a medical student, Ehrlich was captivated by structural organic chemistry and dyes. When he was 23, his first paper was published on selective staining. His doctoral thesis, “Contribution to the Theory and Practice of Histological Staining” contained most of the germinal ideas that would guide his future career. Most of his early work was centered in Berlin at Charité Hospital, where he did pioneering studies on blood and intravital staining, and at Robert Koch's Institute for Infectious Diseases, where he undertook important investigations in Immunology. Ehrlich became an authority on antitoxin standardization and developed the “side-chain theory” of antibody formation for which he was later awarded the Nobel Prize. He became director of an Institute for Experimental Therapy in Frankfurt where he continued research in immunology and carried out routine serum testing. He developed new lines of investigation in cancer research and originated the field of chemotherapy. Using principles developed in his early work with dyes, he successfully treated certain experimental trypanosomal infections with azo dyes. His crowning accomplishment was discovering that the compound Salvarsan could control human syphilis. Ehrlich's legacy in immunology and chemotherapy is discussed and an intimate portrait is drawn of Ehrlich the person.  相似文献   

3.
Jonathon Howard.     
Jonathon 'Joe' Howard (Fig. 1) is Group Leader and Director at the Max Planck Institute of Molecular Cell Biology and Genetics; he and his research group moved to Dresden, Germany, in July 2001. Howard received his PhD in neurobiology in 1983 from the Australian National University in Canberra. He did postdoctoral research there and also at the University of Bristol, UK, and at the University of California, San Francisco. In 1989, he joined the faculty at the University of Washington. His book "Mechanics of Motor Proteins and the Cytoskeleton" was published earlier this year. [interview by Mari N. Jensen]  相似文献   

4.
After the Great Northern War in 1721, Sweden ceased to be an important military power. Instead, the kingdom concentrated on developing science. Swedish research got international fame with names as Carolus Linnaeus, Pehr Wargentin and Anders Celsius. Medical research remained limited and malaria was common especially in the coastal area and along the shores of the big lakes.Already in the beginning of the 18th century Swedish physicians recommended Peruvian bark as medication and they also emphasized that bleeding or blood-letting a malaria patient was harmful. Although malaria was a common disease in the kingdom, the situation was worst in the SW-part of Finland which consisted of the town of Turku and a large archipelago in the Baltic. The farmers had no opportunity to get modern healthcare until Johan Haartman was appointed district physician in 1754. To improve the situation he wrote a medical handbook intended for both the farmers and for persons of rank. Haartman's work was first published 1759 and he discussed all the different cures and medications. His aim was to recommend the best ones and warn against the harmful. His first choice was Peruvian bark, but he knew that the farmers could not afford it. Haartman was appointed professor in medicine at the Royal Academy of Turku in 1765. The malaria situation in Finland grew worse in the 1770's and Haartman analysed the situation. He found the connection between the warm summers and the spring epidemics next year.In a later thesis, Haartman analysed the late summer/early autumn malaria epidemics in the archipelago. Althouh Haartman did not know the connection between malaria and the vector, he gave astute advice and encouraged the farmers to build their cottages in windy places away from the shallow bays in which the Anopheles females hatched. Haartman died in 1788. After his death malaria research in Turku declined. His medical handbook would not be replaced until 1844.  相似文献   

5.
In introgressive hybridization (the repeated backcrossing of hybrids with parental populations), Edgar Anderson found a source for variation upon which natural selection could work. In his 1953 review article “Introgressive Hybridization,” he asserted that he was “bringing taxonomy to the service of genetics” whereas distinguished colleagues such as Theodosius Dobzhansky and Ernst Mayr did the precise opposite. His work as a geneticist particularly focused on linkage and recombination and was enriched by collaborations with Missouri Botanical Garden colleagues interested in taxonomy as well as with cytologists C.D. Darlington and Karl Sax. As the culmination of a biosystemtatic research program, Anderson’s views challenged the mainstream of the Evolutionary Synthesis.  相似文献   

6.
Summary Spallanzani might be considered the founder of modern biology. His great success is mainly due to his incomparable ability in observing things and to the methods he utilised. His investigations into the development of microscopic life in nutrient culture solutions may be considered as decisive steps to counteract the leading theory of spontaneous generation and paved the way for the research work of Louis Pasteur.  相似文献   

7.
IRENE SEBASTIAN 《Bioethics》2012,26(9):504-505
Kevin Smith's utilitarian argument against homeopathy 1 is flawed because he did not review and refute the relevant basic science literature on ultra‐high dilutions. He also failed to appreciate that allopathic medicine is based on a deductive‐nomothetic method and that homeopathic medicine is based on an inductive‐idiographic method, and thus that the implications for clinical research are very different. His misunderstanding of provings and of the holism of homeopathic medicine also demonstrated his failure to understand the history, philosophy and method of homeopathy. Finally, I questioned the value of introducing ethical judgment into an ongoing scientific debate.  相似文献   

8.
Roy Walford died on April 27, 2004, at the age of 79. His contributions to gerontological research in such diverse areas as caloric restriction, genetics of lifespan, immunosenescence, DNA repair and replicative senescence were truly remarkable in their depth and innovation. Significantly, most of the areas that he pioneered during his illustrious research career remain the "hot" areas of current gerontological research. In this sense, he has achieved the most important type of immortality. His death was a major personal and professional loss to numerous scientists within the gerontological community. In launching this new journal on Immunity and Ageing, it is highly fitting, therefore, to remember him on the anniversary of his death by briefly reviewing the contributions of Roy Walford to this important facet of gerontology. Indeed, it was Roy who actually first coined the commonly used term "immunosenescence".  相似文献   

9.
We honor here Thomas (Tom) Roosevelt Punnett, Jr. (May 25, 1926–July 4, 2008), who was a pioneer of Biology, particularly of biochemistry of plants and algae, having specialized in photosynthesis under Robert Emerson of the University of Illinois at Urbana-Champaign. He did exciting work on regulation and control of various metabolic reactions. He was an innovator and raconteur par excellence, and he prized critical thinking. His enthusiasm for basic science questions was matched by his grasp of their “real-world” implications. His last project was a patent for anaerobic sewage treatment that he hoped would lead to solution of waste disposal and energy creation world wide, including the clean-up of Lake Erie, where he had sailed as a boy. On the personal side, he had a strong sense of morality and a great wit and humor.  相似文献   

10.
Streptomycin: discovery and resultant controversy   总被引:1,自引:0,他引:1  
The antibiotic streptomycin was discovered soon after penicillin was introduced into medicine. Selman Waksman, who was awarded the Nobel Prize for the discovery, has since generally been credited as streptomycin's sole discoverer. However, one of Waksman's graduate students, Albert Schatz, was legally recognized as streptomycin's co-discoverer and received a share of the royalties from the drug. The aim of this essay is to discuss the streptomycin story, largely using previously unquoted archival material, and in particular to provide further evidence for the important role which Schatz played in the discovery.  相似文献   

11.
During the 1840s and the 1850s botanist Joseph Hooker developeddistinct notions about the proper characteristics of aprofessional man of science. While he never articulated theseideas publicly as a coherent agenda, he did share his opinionsopenly in letters to family and colleagues; this privatecommunication gives essential insight into his and his X-Clubcolleagues' public activities. The core aspiration of Hooker'sprofessionalization was to consolidate men of science into adutiful and centralized community dedicated to nationalwell-being. The nation in turn owed the scientific community forits ministration. When the government bestowed funds and statuson men of science it was rewarding science – not purchasing it. His proposed reforms were piecemeal, immediate, and above allpractical. He harbored no taste for vast millenariantransformation, and rested his conception of scientificprofessionalism upon a respectable High Victorian foundation ofpatronage and pillars of duty, reciprocity, intimacy, andinequality. The process of professionalization he envisioned wasas much shrewd compromise between existing interests as avindication of principle. His power and prestige from themid-1850s onward gave him considerable ability to carry out hisreform program, although his general success did occasion someundesired consequences for the status of natural-historypursuits. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

12.
The author discusses, on the evidence of some typical examples, some problems in the assessment of homologies which have surfaced by the integration of ultrastructural and genetic evidences in the assessment of the morphologic and evolutionary significance of structures. He thence considers problems of correct assessment of homologies as true apomorphic rather than homoplastic traits and which are often overlooked in the construction of cladistic matrixes. His conclusions are that a more comprehensive approach in morphological research should be stressed and that a strong effort is badly needed for the development of classical comparative anatomy versus the present trend towards ultra specialized studies; moreover, at the present stage of research, the available evidence is generally quite insufficient for the development of reliable matrixes of data, so that a more empirical and pragmatic approach is much safer.  相似文献   

13.
A 7-year-old mentally retarded child was found to be the carrier of a de novo inversion-duplication of 2q35-2qter. His phenotype corresponded to that which is classically described in cases of partial trisomy of the long arm of chromosome 2; however, he did not show the growth retardation which usually characterizes this and other aneuploidy syndromes.  相似文献   

14.
Bibliometric studies have found that male researchers have their greatest productivity around the age of 40, that female researchers produce less than their male colleagues, that incentives for collaboration are slow to affect productivity and that, just like humans, research institutes become larger, less productive, more expensive to maintain and less able to raise money as they grow old. Almost invariably, these conclusions come from statistical studies of large numbers of European and American scientists, and there are practically no studies about tropical researchers. We present an in-depth analysis of the productivity of an internationally recognized tropical botanist and conservationist, Luis Diego Gómez Pignataro, based on the totality of his published work and on our own knowledge, as co-workers and friends, of the life frame in which that scientific output was produced. His life output departs from the expected pattern in that he had the highest productivity before reaching the expected peak productivity age, and that when he reached it his productivity fell and never recovered. Furthermore, marriage did not produce the expected fall in productivity. A close analysis of his life indicates that in the middle of his career he switched to intense teaching and conservation activities, and this better explains why his output of scientific research articles was low afterwards. This switch may occur in other tropical scientists.  相似文献   

15.
In the early 19th century Karl Ernst von Baer initiated a new research program searching for the mechanisms by which an egg transforms itself into an embryo. August Rauber (1841-1917) took up this challenge. He considered the phylogenetic principle as the right tool to explain the similitude of embryogenetic processes. In extending Baer's approach, he combined comparative embryology and histology in his studies of avian and mammalian embryos. His earlier work demonstrated that the two-layered chick embryo is a modified gastrula and not a "disc" as Wilhelm His had claimed. From the 1880s onwards, he concentrated on the issue of how the development of germ layers is related to tissue differentiation. To address this, he studied the blastopore, epiblast, primitive streak, teratology and the relative importance of nucleus and cytoplasm in heredity. This paper reconstructs some of Rauber's work and concludes that his observations and reflections constituted a new approach combining embryology and histology with "phylogenetic" reasoning.  相似文献   

16.
In 1890, Sergei Nikolaevich Vinogradskii (Winogradsky) proposed a novel life process called chemosynthesis. His discovery that some microbes could live solely on inorganic matter emerged during his physiological research in 1880s in Strassburg and Zurich on sulfur, iron, and nitrogen bacteria. In his nitrification research, Vinogradskii first embraced the idea that microbiology could have great bearing on agricultural problems. His critique of agricultural chemists and Kochian-style bacteriologists brought this message to the broader agricultural community, resulting in an heightened interest in biological, rather than chemical methods to investigate soil processes. From 1891 to 1910, he directed the microbiological laboratory at the Imperial Institute of Experimental Medicine in St. Petersburg, Russia, where he expanded his chemosynthesis research to a broad investigation of the manifold significance of autotrophic organisms in soil processes. This work and that of his students attracted the serious attention of agricultural chemists and soil scientists in Russia and abroad, changing essentially the way they understood and investigated the role of microbes in the soil. His student, Vasilii Omelianskii, effectively integrated Vinogradskii’s approach into Russian and Soviet, and international agricultural microbiology. Vinogradskii’s activities in the late 19th century reflect the changes occurring more broadly in science. At that time, microbiologists such as Louis Pasteur, Eugenius Warming, and Martianus Beijerinck were contributing new laboratory methods and theoretical perspectives to incipient disciplines closely related to agriculture: ecology, soil science, and soil microbiology.  相似文献   

17.
Genes encoding the C- and N-terminal regions of SecE were constructed and placed under the control of the tac promoter on plasmids. The C-terminal region of SecE (SecE-C) was sufficient for suppression of the secEcs phenotype, confirming the results of Schatz et al. (Schatz, P. J., Bieker, K. L., Ottemann, K. M., Silhavy, T. J., and Beckwith, J. (1991) EMBO J. 10, 1749-1757). SecE-C allowed the overproduction of SecY, and its overproduction was achieved when the tac-secY gene, on a plasmid, was induced, indicating that the C-terminal region is the site of interaction of SecE with SecY and that the interaction makes the two Sec proteins stable. SecE-C was purified and used with SecY for the reconstitution of protein translocation activity. SecE-C was active in the functional reconstitution. The SecE-C/SecY-dependent protein translocation absolutely required SecA and ATP as the native translocation reaction did. Quantitative analysis revealed that SecE-C was 50% as active as intact SecE. The N-terminal region of SecE (SecE-N) also suppressed in vivo the defect caused by the secEcs mutation. SecE-N was, however, inactive in the overproduction of SecY. A possible oligomeric structure of SecE is discussed.  相似文献   

18.
A new field of gene expression regulation research is emerging that has previously been overlooked. This new area is concerned with distinguishing the expression of a single gene from the averaged expression of many gene copies within the cell population. This paper reviews research focused on individual genes in inducible gene expression systems. The main experimental strategy is to measure the gene expression level of a single cell containing a single reporter gene molecule. In contrast to the commonly held belief, gene induction is found to be stochastic under certain conditions. The possible mechanisms and implications are discussed.  相似文献   

19.
Paolo Sassone-Corsi graduated in genetics at the University of Naples, Italy, and then conducted post-doctoral studies at the CNRS in Strasbourg, France, and at The Salk Institute, San Diego California. After being Directeur de Recherche at the CNRS in France from 1990 to 2006, he moved to the University of California, Irvine, where he is Distinguished Professor and Chair of the Department of Pharmacology. His research focuses on the mechanisms of gene expression, including chromatin remodeling, circadian rhythms and germ cells.  相似文献   

20.
One of the central, unresolved controversies in biology concerns the distribution of primitive versus advanced characters at different stages of vertebrate development. This controversy has major implications for evolutionary developmental biology and phylogenetics. Ernst Haeckel addressed the issue with his Biogenetic Law, and his embryo drawings functioned as supporting data. We re-examine Haeckel's work and its significance for modern efforts to develop a rigorous comparative framework for developmental studies. Haeckel's comparative embryology was evolutionary but non-quantitative. It was based on developmental sequences, and treated heterochrony as a sequence change. It is not always clear whether he believed in recapitulation of single characters or entire stages. The Biogenetic Law is supported by several recent studies -- if applied to single characters only. Haeckel's important but overlooked alphabetical analogy of evolution and development is an advance on von Baer. Haeckel recognized the evolutionary diversity in early embryonic stages, in line with modern thinking. He did not necessarily advocate the strict form of recapitulation and terminal addition commonly attributed to him. Haeckel's much-criticized embryo drawings are important as phylogenetic hypotheses, teaching aids, and evidence for evolution. While some criticisms of the drawings are legitimate, others are more tendentious. In opposition to Haeckel and his embryo drawings, Wilhelm His made major advances towards developing a quantitative comparative embryology based on morphometrics. Unfortunately His's work in this area is largely forgotten. Despite his obvious flaws, Haeckel can be seen as the father of a sequence-based phylogenetic embryology.  相似文献   

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