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1.
In his two-volume monograph Untersuchungen über thierische Elektricit?t, the Berlin physiologist Emil du Bois-Reymond described the relation between nervous electricity and muscle mechanics by way of a long series of experiments. This work is a key text in the history of the experimental life sciences. But it not only contains new findings about the functioning of muscles and its nerves. Du Bois-Reymond practiced an art of experimentation in which aesthetics of mechanical craftsmanship allied itself with the science of physiology. Experimentation, as du Bois-Reymond understood it, was simultaneously an epistemic and an aesthetic practice. The goal of his science was thus producing both knowledge and aesthetic success.  相似文献   

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The torpedo effect was known long before electricity was discovered. How was it explained? In early accounts on the subject, Emil du Bois-Reymond found remarkable observations and hypotheses. In Antiquity, zoological interest is illustrated by Aristotle and followers, who were intrigued by torpedo's behaviour and capacity to act from a distance. Alexandrian physicists were more interested in the propagation, as for light, of its effect in matter, conceived as either corpuscular or continuous. The theory of nervous action is linked to these conceptions and separated in various hypotheses among which that on qualitative alteration. However, the medical approach of toxicology takes over this debate and brings back torpedo's property in the frame of pathology.  相似文献   

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At the first International Congress of Physiologists in Basel, Switzerland, the Italian physiologist Angelo Mosso (1846-1910) discussed his findings on muscular fatigue while demonstrating the functioning of an ergograph (work recorder). One hundred sixteen years later, Mosso's career, scientific accomplishments, and legacy in the study of muscular fatigue were commemorated at the 2005 International Congress of Physiological Sciences. After receiving his degree in Medicine and Surgery from Turin, Italy, in 1870, Mosso was able to study and interact with renowned physiologists as Wilhelm Ludwig, Du Bois-Reymond, Hugo Kronecker, and Etienne Marey. By 1879, he was Professor of Physiology at the University in Turin, where he conducted research pertaining to blood circulation, respiration, physical education, high-altitude physiology, and muscular fatigue. Using tracings from the ergograph (concentric contractions of the flexor muscles of the middle finger that were volitionally or electrically stimulated), he was able to characterize muscle fatigue and to associate its occurrence with central or peripheral influences. He demonstrated that exercise would increase muscular strength and endurance while prolonging the occurrence of fatigue, which he postulated was a chemical process that involved the production of toxic substances such as carbonic acid. The phenomenon of contracture was described, and his collective studies led to the formulation of laws pertaining to exhaustion and to the 1891 publication of La Fatica (Fatigue). Besides La Fatica, Mosso will be remembered as a scientist with a love for physiology, a concern for the social welfare of his countrymen, and as one who sought to integrate physiological, philosophical, and psychological concepts in his experimental studies.  相似文献   

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The most important and best-known merit of Hermann Schaaffhausen is the correct explanation of the Neanderthal man as a fossil human being. Considering his work in the field of paleoanthropology one can designate him as the founder of this anthropological discipline in Germany. Beyond that he was also very active in the "Deutsche Anthropologische Gesellschaft" of the 19th century and played an important role as an editor of the journal "Archiv für Anthropologie". Thus, Hermann Schaaffhausen can be considered as one of the most important founders of Physical Anthropology in Germany. He belongs to those persons to whom German Anthropology owes its acknowledgement as an academic subject in German universities.  相似文献   

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This essay is dedicated to the proposition that Hermann Joseph Muller, widely regarded as the greatest geneticist of the first half-century of the subject, was also one of the greatest evolutionists of this period. His Nobel Prize-winning work, which showed that radiation increases the mutation rate, is in every genetics textbook, and his prescient ideas have influenced almost every aspect of the discipline. Here I emphasize his less well-known contribution to the neo-Darwinian theory of evolution.  相似文献   

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During a scientific examination in July 1999 both crypts below the St. Martin's Church in Grünstadt, Germany, were opened and 9 coffins from the county family of Leiningen examined. This paper is concentrating on one of these persons: Georg Hermann (1679-1751), count of Leiningen-Westerburg-Altleiningen, who gave during the 18. century the city its barock character. He was also responsible for the rebuilding of the church. His skeleton revealed interesting pathological changes. Few years before his death the count had the accident to get run over by a heavy wagon which crushed the distal part of his legs. The fractures healed, but gave him an ancylotic and shortened left leg, which must have caused him a lot of suffering in his last years.  相似文献   

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Constantin von Monakow (1853-1930), director of the Brain Anatomy Institute in Zurich, was a pioneer in the early history of interdisciplinary brain sciences. The elucidation of connectivity in sensory and motor pathways was richly illustrated in two landmark monographs: Pathologie du cerveau (1897) and La localisation de l'encephale et la dégradation fonctionelle par des lésions circonscrites du cortex cérébral (1914). His special merit was to conceptualize his accumulating results. As to his term 'diaschisis': (1) neurological lesion are rarely restricted to a histologically defined neural structure; (2) any brain focus is interconnected with remote structures - thus, dependent structures are deafferented from the lesioned territory (= 'diaschisis') -; (3) dependent structures, however, gradually regain some autonomy, as reflected in partial behavioral recovery. His term 'chronogenic localization' was used for the brain's fundamental organization in time-dependent network constellations. Monakow attracted many researchers, particularly from Japan. He was an engaged member of the International Brain Commission until its dissolution during World War I.  相似文献   

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It was in the first half of the 18th century when life sciences started to flourish in the independent republic of Geneva. However, it is difficult to identify a genuine school of developmental biologists during that era. Nevertheless, several prominent scientists over the past two and a half centuries have established and maintained a strong tradition of studies in embryological development and reproduction. In this short historical account, we briefly pay tribute to these famous forerunners, by emphasizing both the originality and quality of their work, as well as the many accompanying conceptual and methodological advances. We start with Abraham Trembley (1710-1784) and the discovery of Hydra and of regeneration, and with Charles Bonnet (1720-1793) who, amongst other contributions, first observed parthenogenetic development. In the 19th century, Carl Vogt (1817-1895) and Edouard Claparède (1832-1871) were well-known scientists in this field of research, whereas Hermann Fol (1845-1892) can be considered as one of the pioneers, if not the founder, of causal embryology, through his experiments on lateral asymmetry in manipulated chicken. More recently, Emile Guyénot (1885-1963) and Kitty Ponse (1897-1982) perpetuated this tradition, which is well alive nowadays in the city of Calvin.  相似文献   

10.
New investigations on Otto Hauser's skeleton findings and the excavations of this Swiss citizen in Southwest France from 1906 until 1914 placed the activities of this archaeologist again in the focus of scientific and public interest. This paper describes life and oeuvre of Otto Hauser and discusses the importance of the skeletons found by him and Hermann Klaatsch as well as the consequences of their discovery. The efforts of Otto Hauser to publish his discoveries, to present and spread his view concerning the evolution of man were remarkably manifold as well as the parallels between ancient man and contemporary ethnic groups living on a low technological level drawn by him and to wake and to promote the interest in prehistory. Many books, brochures, articles and public lectures contributed to this intention as well as co-operation with local historians and scientists of other disciplines, and also many films, teaching and illustrative materials. The scientific collection of the authors of this article comprises more than 6,500 written documents and photos.  相似文献   

11.
When observers view a grid of mid-gray lines superimposed on a black background, they report seeing illusory dark gray smudges at the grid intersections, an effect known as the Hermann grid illusion. The strength of the illusion is often measured using the cancellation technique: A white disk is placed over one of these intersections and the luminance of the disk is reduced until the disk disappears. Its luminance at this point, i.e., the disk's detection threshold, is taken to be a measure of the strength of the illusion. Our experiments showed that some distortions of the Hermann grid, which were sufficient to completely disrupt the illusion, did not reduce the disk's detection threshold. This showed that the cancellation technique is not a valid method for measuring the strength of the Hermann grid illusion. Those studies that attempted to use this technique inadvertently studied a different effect known as the blanking phenomenon. We conclude by presenting an explanation for the latter effect.  相似文献   

12.
The Nobel Prize for chemistry of 1955 was awarded to Vincent du Vigneaud. After a brief outline of his career and accomplishments, some archive material related to this decision of the Royal Swedish Academy of Sciences is presented. Other archive studies have shown that du Vigneaud was also considered for the corresponding prize in physiology or medicine.  相似文献   

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We study an algorithm which allows sequences of binary numbers (strings) to interact with each other. The simplest system of this kind with a population of 4-bit sequences is considered here. Previously proposed folding methods are used to generate alternative two-dimensional forms of the binary sequences. The interaction of two-dimensional and one-dimensional forms of strings is simulated in a serial computer. The reaction network for the N = 4 system is established. Development of string populations initially generated randomly is observed. Nonlinear rate equations are proposed which provide a model for this simplest system.Dedicated to Professor Hermann Haken on the occasion of his 65th Birthday  相似文献   

15.
We report the first case of egg isolation of the Asian fish tapeworm Bothriocephalus acheilognathi (Bothriocephalidea) from human stool. A male patient from Saint Laurent du Maroni (French Guiana) presenting abdominal pain was examined in France for the diagnosis of intestinal parasites. Diphyllobothrium-like eggs were observed in his stool. However, molecular phylogenetic analyses based on sequences of rDNA and COI genes showed that the eggs observed belong to a bothriocephalidean cestode B. acheilognathi. The adult life stages of B. acheilognathi cestodes are known as invasive parasites of a wide spectrum of fish; however, they have not been described to parasitize any mammals. This human infection seems to be accidental and represents a parasite passage through human intestine after the consumption of an infected fish host.  相似文献   

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A new species of Batillipedidae, Batillipes spinicauda, has been found in subtidal sand sediments collected in Orosei Gulf (Sardinia, Tyrrhenian Sea). The most important peculiarities of the new species are the shape of the primary clavae, lateral processes and caudal apparatus. In the same samples, B. littoralis Renaud-Debyser, 1959 and Orzeliscus belopus Du Bois-Reymond Marcus, 1952 were found.  相似文献   

18.
Summary Light- and electron-microscopic studies were performed on those tissues that are supposed to deliver the anlagen of the extrinsic ocular muscles. Since the blastemata of the ocular muscles can be traced back into the prechordal mesoderm, it can be concluded that this tissue is the source of these muscles. In embryos from stage 8–10 according to Hamburger and Hamilton (HH) cells are found to detach from the lateral border of the prechordal mesoderm. These cells are assumed to give rise to the trochlearis and abducens musculature. In stage-14 embryos the paired premandibular cavity arises within the lateral wings of the prechordal mesenchyme. In 4-day embryos the lateral wall of each premandibular cavity becomes denser forming a premuscular mass, which is subdivided into the anlagen of the oculomotorius muscles in 5-day embryos. The head cavities are not homologous to somites because their structures, origins and sites are very different.This work was supported by a grant from the Deutsche Forschungsgemeinschaft (CH 44/6-1).This paper is dedicated to Prof. Dr. med. Dr. h.c. Hermann Voss on the occasion of his 90th birthday.  相似文献   

19.
Valentinuzzi ME  Beneke K  González GE 《IEEE pulse》2012,3(4):68-9, 72, 74-5 passim
On the basis of the strict exclusion of the vis vitalis, the demand was raised by Carl Ludwig, Helmholtz, Du Bois-Reymond, and Brucke for a physiology which was causal-analytical and physically and chemically experimental. If, out of these four investigators, we pick Ludwig as the actual founder of modern physiology, the grounds for this must be justified specifically. That modern physiology is not to be contemplated without the works of the three great students of Johannes Muller is explicitly emphasized. However, Carl Ludwig occupies a special position for physiology.  相似文献   

20.
Mucopolysaccharidosis type I (i.e., Hurler, Hurler-Scheie, and Scheie syndromes) and type II (i.e., Hunter syndrome) are lysosomal storage disorders resulting from alpha-L-iduronidase (IDUA) deficiency and iduronate-2-sulfatase (IDS) deficiency, respectively. The a priori probability that both disorders would occur in a single individual is approximately 1 in 5 billion. Nevertheless, such a proband was referred for whom clinical findings (i.e., a male with characteristic facies, dysostosis multiplex, and mental retardation) and biochemical tests indicated these concomitant diagnoses. In repeated studies, leukocyte 4 methylumbelliferyl-alpha-L-iduronidase activities in this kindred were as follows: <1.0 nmol/mg protein/h in the proband and proband's clinically normal sister; 45.3 in mother; and 45.7 in father (normal range 65.0-140). Leukocyte L-O-(alpha-iduronate-2-sulfate)-(1->4)-D-O-2,5-anhydro[1-3H]mannitol-6- sulfate activities were as follows: 0.0 U/mg protein/h in the proband; 5.7 in his sister; 4.9 in mother; and 15.0 in father (normal range 11.0-18.4). Multiple techniques, including automated sequencing of the entire IDS and IDUA coding regions, were employed to unravel the molecular genetic basis of these intriguing observations. The common IDS mutation R468W was identified in the proband, his mother, and his sister, thus explaining their biochemical phenotypes. Additionally, the proband, his sister, and his father were found to be heterozygous for a common IDUA mutation, W402X. Notably, a new IDUA mutation A300T was also identified in the proband, his sister, and his mother, accounting for reduced IDUA activity in these individuals; the asymptomatic sister, whose cells demonstrated normal glycosaminoglycan metabolism, is thus a compound heterozygote for W402X and the new allele. This A300T mutation is the first IDUA pseudodeficiency gene to be elucidated at the molecular level.  相似文献   

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