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1.
It has been and still is commonly believed by geologists and historians of geology alike that geological theory is an extrapolation from the empirical knowledge of the geology of a region. Abraham Gottlob Werner (1749–1817), whose theory concerning the origin of basalt and the minor role of volcanoes and the major role of water in the history of the earth's crust was eventually proven wrong in some respects, is usually cited as the prime example of a geologist who had not ventured beyond the confines of his native region, Saxony, and had developed a universal geological theory based almost entirely on his observations of that region. In this essay I show that the geology of Saxony played a relatively unimportant role in the development of Werner's universal geological theory; that he became a neptunist before he had closely examined the geology of Saxony; and that his explanation of the history of the earth's crust was as reasonable, if not more reasonable, than the explanations brought forth by those of his contemporaries who opposed his views.  相似文献   

2.
Summary The concentration of GABA was determined in each ganglion ofAplysia kurodai by microassay. Highest concentration was observed in buccal ganglia.The authors are indebted to Miss C. Shimada for her skillful assistance and are also grateful to Dr. H. Koike in our institute for his advice to handleAplysia, to Dr. S. Ameniya, Misaki Marine Biology Station, University of Tokyo, for his support to get the animals.  相似文献   

3.
Summary The ultrastructural morphology of the clonal insulin-producing cell line, RINm5F, was investigated. Virus-like particles, probably C type viruses, were identified both intra- and extracellularly. Because these particles could not be found in the original transplantable tumor, it is probable that viruses were induced at some later stage in the development of the RINm5F cell line. All investigators using the RINm5F cells should be aware of the fact that these cells may contain one or several types of viruses, and of the possibility that these particles may interfere with a variety of cellular functions.This work was supported by grants from the Lake County Medical Center Developmental Agency (to VH and PWB) and the American Heart Association, Indiana Affiliate (to PWB,*USA) and by the Swedish Medical Research Council (12X-562), the Swedish Diabetes Association, the Nordic Insulin Foundation and Åke Wibergs Foundation (**Sweden). Per-Olof Berggren is a recipient of a postdoctoral fellowship from the Swedish Medical Research Council.  相似文献   

4.
Zusammenfassung Nach i.p. Injektion von 5-Fluorouracil-3H wurde bei Ratten zu verschiedenen Zeiten die RNS-Neubildung der Leber bestimmt. Die Resultate sprechen dafür, dass Fluorouracil in die ribosomale RNA der Leber eingebaut wird.

This work was supported by grants from the Swedish Medical Research Council (Project No. K68-12X-623-04), the Swedish Cancer Society (Project No. 95-K68-02X), the Faculty of Medicine, University of Uppsala, Sweden, and the Swedish Society for Medical Research.  相似文献   

5.
During the Napoleonic Wars there was a shortage of suitable millstones for the British Ordnance gunpowder mills. John MacCulloch spent five summers searching Western Britain for a source of non-siliceous limestones to be used as gunpowder millstones. His search was authorized by the Board of Ordnance, which also paid all his expenses.

By 1812 MacCulloch had found suitable limestones in Sutherland, Skye, and at Glen Tilt, but the Board of Ordnance were unable to exploit any of the sources until 1815 when unsuccessful quarries were opened on Skye. After the defeat of Napoleon at Waterloo the British millstone project was abandoned. The military objective of the millstone survey was not achieved, but MacCulloch learned much about the geology of the older rocks of Britain and he built a reputation as an expert geologist through the papers he submitted to the Geological Society of London.  相似文献   

6.
A great deal is known about the technical issues surrounding the introduction of Hugo De Vries's mutation theory and the subsequent development of the modern genetical theory of natural selection. But so far little has been done to relate these events to the wider issues of the time. This article suggests that extra-scientific factors played a significant role, and substantiates this by comparing De Vries's respect for the original Darwinian spirit with Thomas Hunt Morgan's use of the mutation theory as part of an attack on the whole philosophy of Darwinism. In particular, it is argued that Morgan's attitude was dictated by his moral objections to the picture of a world dominated by struggle.  相似文献   

7.
Zusammenfassung Die Messung des Denaturationsdunktes als Parameter für die thermale Reaktion des Kollagens in geometrisch komplexen Geweben oder von Kollagenen verschiedener Reifegrade wird beschrieben und Beispiele im Bereich von Altersunterschieden und Wundheilung werden gegeben.

This work was supported by Swedish Medical Research Council (Project No. B70-12X-2883-01) and by Carin Trygger Memorial Fund through the Swedish Society of Medical Sciences and performed at the Department of Anatomy, University of Gothenburg, Sweden.

The technical assistance of MissUlla-Britt Lindgren in the development of this method is gratefully acknowledged.  相似文献   

8.
Summary Rabbits were subjected to infrared irradiation of the iris 1 month after unilateral cervical sympathectomy. The resulting breakdown of the blood-aqueous barrier was greatly enhanced on the sympathectomized side. In contrast, the response to intravitreally injected substance P (SP) was the same in both eyes. The enhancement of the response to IR irradiation could be abolished by pretreatment with an SP antagonist, (D-Pro2, D-Trp7,9)-SP.This study was supported by grants from the Swedish MRC (04X-1007, 14X-2321), the Medical Faculty of Lund, Ferring Arzneimitel, Kiel (Federal Republic of Germany) and Ferring Pharmaceuticals, Malmö (Sweden).  相似文献   

9.
Zusammenfassung Die isolierte pulsatile Flughaut-Vene der Fledermäuse zeigt mit dem «Sucrose-gap» eine enge elektro-mechanische Korrelation. Das AP ist oft von einem Schrittmacher-Potential eingeleitet. Solche AP sind äusserst selten bei den Gefässmuskeln.

This study was supported by grants from the Swedish Medical Research Council (28-14 x), the G. and A. Claraz-Schenkung and the Swiss National Scientific Research Funds, and was carried out in the Department of Physiology, University of Lund, Sweden.  相似文献   

10.
Scottish publisher and naturalist Robert Chambers pursued an amateur interest in geology through much of his life. His early measurements of raised beaches in Scotland earned him membership in the Geological Society of London in 1844, a recognition much appreciated by the anonymous author of the ‘scandalous’ Vestiges published the same year. Although familiar with emerging ice age theories, Chambers remained with most British geologists a sceptic through the 1840s, even after a trip to the glaciers of the Alps in 1848, which nevertheless prepared him for the turning point, which came in 1849 during an extensive field trip in Norway and Sweden. Here a wealth of observations left him in no doubt that vast glaciers had formerly covered Scandinavia, polishing cliffs, scouring striations, depositing old moraines and erratic boulders. This also led him to a new glacial reading of the British landscape, and with the ardent conviction of a fresh convert he became one of the most vocal supporters of glacial theory in Britain in the 1850s at a time when the iceberg drift theory for boulder transport was still favoured by most prominent British geologists. While Chambers through his popular Chambers’s Edinburgh Journal communicated his travels and ice age vision to a wide audience, and also pointed out ice age evidence on guided excursions around Edinburgh, he did not enter this new vision into subsequent editions of Vestiges, probably in order not to reveal its author. This paper explores Chambers’s contributions to the ice age debate, his field trips and the genesis of his convictions, and evaluates his impact on the scientific debate.  相似文献   

11.
Copernicus’s De revolutionibus (1543) and Girolamo Fracastoro’s Homocentrica (1538) were both addressed to Pope Paul III (1534-1549). Their dedicatory letters represent a rhetorical exercise in advocating an astronomical reform and an attempt to obtain the papal favour. Following on from studies carried out by Westman (1990) and Barker & Goldstein (2003), this paper deals with cultural, intellectual and scientific motives of both texts, and aims at underlining possible relations between them, such as that Copernicus knew of Fracastoro’s Homocentrica, and that at least part of the rhetorical strategy laid out in De revolutionibus’s dedicatory letter can be read as a sophisticated response to Fracastoro’s arguments.  相似文献   

12.
Résumé Avec la méthode à la fluorescence deFalck etHillarp on montre que lors d'une perfusion selonIversen avec haute concentration de noradrenaline il se produit une accumulation d'amine aussi bien intra- qu'extraneuronale. Les varicosités des nerfs sont agrandies et tordues.

This work was supported by grants from the Swedish Medical Research Council (project No. B67-12X-712-02A) and by the Faculty of Medicine, University of Lund, Sweden.  相似文献   

13.
Summary Inhibitory effects on fertilization of the ascidian of three benzyloxycarbonyl(Z)-aminoacyl prolinals and Z-Gly-Pro-chloromethyl ketone added before and after insemination were examined. The results suggest that the prolyl endopeptidase is involved in the process of fertilization, especially in a process taking place between chorion elevation and cell cleavage.Acknowledgment. We are indebted to Dr T. Numakunai of the Marine Biological Station of Tohoku University for collecting the ascidians and to Dr M. Hoshi of the Tokyo Institute of Technology for his helpful discussion. We are also grateful to Dr T. Yoshimoto and Prof. D. Tsuru of Nagasaki University for their generous gift of Z-Gly-Prochloromethyl ketone. This work was supported by a Grant-in-Aid from the Ministry of Education, Science and Culture of Japan.  相似文献   

14.
This paper examines the life and work of T. C. Chamberlin, a prominent glacial geologist who developed an interest in interdisciplinary earth science. His work on the geological agency of the atmosphere informed his understanding of climate change and other terrestrial phenomena and led him to propose a new theory of the formation of the Earth and the solar system.Chamberlin's graduate seminar at the University of Chicago in 1896 contained all the themes that informed his research programme over the next three decades. These included the carbon dioxide theory of climate change in its relationship to diastrophism and oceanic circulation, the role of water vapour feedbacks in the climate system, and the relationship between multiple glaciations, the climate system, and the formation of the planet.  相似文献   

15.
Bailey Willis was the second major American geologist to undertake reconnaissance research in China--in the years 1903-04. Together with the stratigrapher Eliot Blackwelder, topographer Harvey Sargent, and guide Li Shan, he travelled first in Shandong Province, then from Peking to Xian, thence across the mountains into Sichuan, and then by river via the Yangzi Gorges to Shanghai. It was hoped that they would discover the primeval ancestor of trilobites in China, but the search proved unsuccessful. Willis's stratigraphic findings are described, as are his structural interpretations of what he observed in China. His work in China gave rise to some unfounded speculations about the possible causes of lateral Earth movements, due to rocks of different densities being adjacent to one another in the Earth's crust. These ideas were followed by several other 'theories of the Earth' during Willis's later career, some of which were also probably related to his experiences in China. He seemingly practised the formulation of 'multiple working hypotheses'. The paper also discusses the influence of Willis's survey and stratigraphic work on the subsequent development of Chinese geology, with particular attention given to the various meanings of the term 'Sinian System'. Mention is made of later work in China on Lower Cambrian stratigraphy.  相似文献   

16.
Zusammenfassung An narkotisierten Katzen wurden der arterielle Blutdruck und der venöse Ausfluss aus der Vorderpfote oder aus dem Hinterbein registriert. Injektionen von Histamin in die Hirnventrikel bewirkten Erhöhung des Blutdruckes und Vasokonstriktion in der Vorderpfote. Im Hinterbein war die Vasokonstriktion weniger ausgesprochen. Auch nach Entfernung der Nebennieren war der Pressoreffekt vorhanden, woraus folgt, dass die periphere Vasokonstriktion für den durch intraventrikuläres Histamin hervorgerufenen Pressoreffekt verantwortlich ist.

This work was supported by the Swedish Medical Research Council (Project No. W 349). Rheomacrodex was kindly supplied by Pharmacia, Uppsala (Sweden).  相似文献   

17.
Following demands to regulate biomedicine in the post-war period, Sweden saw several political debates about research ethics in the 1970s. Many of the debates centered on fetal research and animal experiments. At stake were questions of moral permissibility, public transparency, and scientific freedom. However, these debates did not only reveal ethical disagreement—they also contributed to constructing new boundaries between life-forms. Taking a post-Marxist approach to discursive policy analysis, we argue that the meaning of both the “human” and the “animal” in these debates was shaped by a need to manage a legitimacy crisis for medical science. By analyzing Swedish government bills, motions, parliamentary debates, and committee memorials from the 1970s, we map out how fetal and animal research were constituted as policy problems. We place particular emphasis on the problematization of fetal and animal vulnerability. By comparing the debates, we trace out how a particular vision of the ideal life defined the human-animal distinction.  相似文献   

18.
The revolution in geology, initiated with Alfred Wegener’s theory of continental drift, has been the subject of many philosophical discussions aiming at resolving the problem of rationality underlying this historical episode. Even though the debate included analyses in terms of scientific methodology, applications of concrete accounts of epistemic justification to this case study have been rare. In particular, the question as to whether Wegener’s theory was epistemically worthy of pursuit in the first half of the twentieth century, that is, in its early development, remained open or inadequately addressed. The aim of this paper is to offer an answer to this question. The evaluation of Drift will be done by means of an account of theory evaluation suitable for the context of pursuit, developed in ?e?elja and Straßer (accepted for publication). We will argue that pursuing the theory of continental drift was rational, i.e., that it was irrational to reject its pursuit as unworthy.  相似文献   

19.
Summary A single i.p. injection of lithium chloride (5–7.5 moles/g b.wt) in mice caused a 70–80% decrease in renal, cardiac and splenic ornithine decarboxylase (ODC) activity within 1 h, whereas pulmonary ODC activity was unaffected. Lithium chloride did not have any effect on ODC activity in vitro when added to homogenates of the tissues studied. We suggest that the effect of lithium on ODC activity is not direct, but mediated via e.g. hormonal or nervous influence.This study was supported by grants from the Swedish Medical Research Council (04X-02212, 14X-00028), and the Faculty of Medicine, University of Lund (Sweden).  相似文献   

20.
Summary VIP-containing nerve fibers as well as cholinergic nerve fibers have a ubiquitous distribution in the body and both types of nerves have been demonstrated to innervate the pancreatic islets. The present study shows, in the intact, conscious mouse, that VIP and the cholinergic agonist carbachol stimulate glucagon secretion in a dose-dependent manner. Furthermore VIP and carbachol were found to exert potentiating interactions on glucagon secretion. These results suggest the existence of an interactive neural regulation of glucagon secretion, exerted by acetylcholine and VIP.We thank Professor V. Mutt, Karolinska Institutet, Stockholm, for giving us VIP. The skilful technical assistance of Lena K vist and Peter Okmark is gratefully acknowledged. This study was supported by grants from the Swedish Medical Research Council (14P-4289, 14X-4286) and the Medical Faculty, University of Lund, Sweden.  相似文献   

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