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21.
Zusammenfassung Eine isotopische Methode zur Bestimmung der DH-Aktivität wird beschrieben. Die Methode wurde verwendet zur Bestimmung der DH-Aktivität im menschlichen Serum und in verschiedenen Organen der Ratte. Das sympatische Nervensystem des Menschens kann mit dieser Methode weiter erforscht werden.

This work was supported by USPHS Grant No. 5 R01 MH-02717-12.  相似文献   
22.
This is a contribution towards a history and philosophy of modeling in its early stages in electromagnetism. In 1873, James Clerk Maxwell (1831–1879) hinted at the methodology of modeling at the end of his Treatise on Electricity and Magnetism. We focus on Maxwell's impact on physicists who immediately followed him, specifically Oliver Lodge (1851–1940) and George Francis FitzGerald (1851–1901). We begin with the role that the scientific concept of model played in the late nineteenth century, as assessed by Ludwig Boltzmann (1844–1906). We then discuss the role of hypothesis as a methodology, the appeal to (dynamical) illustration, and the way Maxwell applied model and working model in his studies of electromagnetism. We show that for Maxwell these key terms were kept distinct, but Lodge did not maintain these distinctions and, in this regard, FitzGerald followed Lodge. Notwithstanding Lodge's influence, Fitzgerald modified Maxwell's theory based on the mechanical model he designed, thereby implicitly taking the first step towards modeling. This methodology consists in drawing consequences from the (mechanical) model to the (electrodynamic) theory and modifying the latter in light of the functioning of the former. At the core of our argument is the thesis that it was a methodological novelty to move from the concept of model to the methodology of modeling. The introduction of modeling as a new methodology into physics in the late nineteenth century was a major event which deserves proper recognition.  相似文献   
23.
24.
The focus with which the paper is concerned is the process or task of intervention and, more specifically, the exploration of three (overlapping and interacting) questions pertinent to those who would intervene:
  • What is to be done?
  • How shall we decide what to do?
  • What can guide our actions?
  • In terms of what we will describe as pragmatic pluralism (our response to these questions), we intend this to be read in several different ways and on several different levels. Illustrating the discussion with examples from a number of different case studies, we will talk about pluralism in each of the following features:
  • in the use of specific methods/techniques
  • in the role(s) of the interventionists
  • in the modes of representation employed
  • in the use of different rationalities
  • in the ‘nature’ of the client
  •   相似文献   
    25.
    The known Mountain Plover population breeding on the Myton Bench, Duchesne County, Utah, is small, composed roughly of 30 adults and young after each breeding season. Currently, its location is peripheral to the species main range. This shrub-steppe breeding habitat differs from the shortgrass prairie habitat with which this bird is historically associated. Between 1996 and 1998 we made observations at nesting sites located consistently in 2 concentrated areas surrounded by large tracts of similar habitat. Activity may be focused in these specific areas because of breeding-site fidelity; this behavior is common among most shorebirds and has been documented for the Mountain Plover in Colorado. Also, Mountain Plovers are social and tend to choose nest sites near others. Most nests in Utah were located within close proximity of mounds of white-tailed prairie dogs ( Cynomys leucurus ), and all were situated near roadways or oil well pads. Mountain Plovers were often observed with broods on these bare areas at night. We conclude that Mountain Plovers on the Myton Bench are distributed in clumped breeding colonies within large areas of apparently favorable habitat.  相似文献   
    26.
    E Goldstein  W S Tyler  P D Hoeprich  C Eagle 《Nature》1971,229(5282):262-263
      相似文献   
    27.
    28.
    Summary ß-(p-hydroxyphenyl)ethanol is present in the chest gland secretion of the galago Galago crassicaudatus.  相似文献   
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    30.
    Zusammenfassung Injektion von Sekretin ruft bei normalen Versuchspersonen Diuresis und Vermehrung der Natrium- und Alkali-Ausscheidung hervor. Diese Wirkungen sind vermindert bei Patienten mit chronischer Pankreaserkrankung. Der mögliche Mechanismus und die praktische Bedeutung dieser Beobachtungen werden diskutiert.

    Supported successively by grants from the Royal Free Hospital Endowment Fund.  相似文献   
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