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851.
Upper limb reduction was diagnosed by ultrasound scan at 17 weeks after chorion villus sampling at 9 weeks' gestation. Pregnancy was terminated and necropsy confirmed limb reduction in an otherwise normal fetus. The relationship of limb reduction to amniotic band syndrome is discussed.  相似文献   
852.
Online searching in publically available patent files opens up interesting possibilities to provide a rapid response to critical questions. A computerized analysis of all patents of leading German pharmaceutical companies over the last decade in important indication areas is described. Supported by subsequent manual processing of individual patents it is shown that duplicate experiments on animals practically never occur.  相似文献   
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The excellent technical assistance of H. Führer and I. Leib is appreciated. Part of the work was supported by the Bundesministerium für Forschung und Technologie, the Deutsche Forschungsgemeinschaft, the Fonds der Chemischen Industrie, and from the Leitz and Hoechst companies. This paper is part of the M. D. thesis of Ch.L.  相似文献   
855.

Naturwissenschaften Aktuell

Konzept für konzentrierte Meeresforschung an fünf Orten  相似文献   
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This paper presents a new tool for promoting business sustainability — indicators of sustainable production. It first introduces the concept of sustainable production as defined by the Lowell Center for Sustainable Production, University of Massachusetts Lowell. Indicators of sustainable production are discussed next, including their dimensions and desirable qualities. Based on the Lowell Center Indicator Framework, the authors suggest a new methodology of core and supplemental indicators for raising companies' awareness and measuring their progress toward sustainable production systems. Twenty-two core indicators are proposed and a detailed guidance for their application is included. An eight-step model provides a context for indicator implementation. The paper concludes with a summary of the strengths and weaknesses of the methodology as well as recommendations for testing the indicators.  相似文献   
859.
 This study investigated the influence of cat urine odour in suppressing development and fertility in Campbell's hamster males. Exposure to this odour from postnatal day 11 until day 45 (sexual maturation) resulted in reduced sex organ weights, reduced testosterone levels and in an increase in abnormalities of the synaptonemal complex in both sex chromosomes and autosomes. Subsequent breeding experiments revealed a significant decrease in litter size. All these data indicate a severe effect of predator odour on the breeding success of potential prey species. It is assumed that these effects are caused by the sulphurous compounds in the urine; however, the underlying mechanisms are not yet known. Received: 31 January 2000 / Accepted in revised form: 6 June 2000  相似文献   
860.
 The Australian buprestid beetle Merimna atrata (Coleoptera: Buprestidae) approaches forest fires because its larvae develop in freshly burnt wood. So far nothing is known about possible sensory systems enabling the beetles to detect fires and to cope with the thermal environment close to the flames. We found that M. atrata has two pairs of infrared (IR) organs on the ventrolateral sides of the abdomen. Each IR organ consists of a specialized IR-absorbing area which is innervated by one thermosensitive multipolar neuron. The primary dendritic branches ramify into more than 800 closely packed terminal endings which contain a large number of mitochondria. We called the special morphology of the dendritic region a terminal dendritic mass. The type of IR receptor found in M. atrata is unique in insects and can best be compared with the IR organs of boid snakes. Received: 14 August 2000 / Accepted in revised form: 18 October 2000  相似文献   
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