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1.
This paper traces the reception of Babylonian astronomy into the history of science, beginning in early to mid twentieth century when cuneiform astronomical sources became available to the scholarly public. The dominant positivism in philosophy of science of this time influenced criteria employed in defining and demarcating science by historians, resulting in a persistently negative assessment of the nature of knowledge evidenced in cuneiform sources. Ancient Near Eastern astronomy (and astrology) was deemed pre- or non-scientific, and even taken to reflect a stage in the evolution of thought before the emergence of science (in ancient Greece). Two principal objections are examined: first, that the Near East produced merely practical as opposed to theoretical knowledge and, second, that astronomy was in the service of astrology and religion. As the notion of a universal scientific method has been dismantled by post-positivists and constructivists of the second half of the twentieth century, an interest in varieties of intellectual and cultural contexts for science has provided a new ground for the re-consideration of Babylonian astronomical texts as science developed here.  相似文献   

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Summary In this study we have analyzed the sterol compositions of two continental shelf species of crustacea, the lobster (Homarus americanus) and the shrimp (Pandalus borealis). Cholesterol was found to be the most abundant sterol in these two species with smaller amounts of desmosterol, 24-methylcholesterol, 24-ethylcholesterol, 24-methylenecholesterol and 22-dehydrocholesterol. Woods Hole Oceanographic Institution Contribution Number 3494. This work was supported by the Office of Sea Grant of the National Oceanic and Atmospheric Administration, U.S. Department of Commerce. Special thanks are extended to Ms.R. Beebe-Center, who was responsible for a large part of the isolation work described here.  相似文献   

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Zusammenfassung In dieser Arbeit ist eine Theorie der Nierenfunktion entwickelt worden, welche eine Wechselbeziehung zwischen den antidiuretischen und natriumretendierenden Hormonen aufzeigt. Durch diese Theorie werden einige bisher nicht verständliche Phänomene der Nierenphysiologie erklärt.  相似文献   

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In this paper,the effects of Si and Ce on the microstructure and hydrogen storage property of Ti26.5 Cr20V45Fe8.5Ce0.5 alloy were studied,respectively.First of all,effects of Si on the microstructure and hydrogen storage properties of Ti26.5Cr20(V45Fe8.5)1-xSixCe0.5(x=0,0.5,1.0,1.5 and 2.0 at%)alloys were studied by X-ray diffraction,scanning electron microscopy and P-C isotherm measurements.As the Si addition increases,the hydrogen absorption capacities of alloys decrease but the equilibrium pressure incre...  相似文献   

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Riassunto Il Crostaceo AnfipodeTalitrus saltator (Montagu) possiede un meccanismo di orientamento solare che gli permette, mediante una variazione regolare e continua dell'angolo di orientamento nel corso del giorno, di mantenere una direzione di fuga praticamente costante. Esemplari del litorale tirrenico, trasportati in Argentina, hanno assunto un angolo di orientamento col sole conforme all'ora italiana nel momento della esperienza. Ciò dimostra che la regolazione dell'angolo di orientamento è dovuta ad un fattore endogeno e cioè che esiste inTalitrus un senso del tempo.  相似文献   

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Zusammenfassung Vasopressin in den Blutdruck nicht erhöhenden geringen Dosen (0.01 E/kg i.p.) verringert die Hautdurchblutung der Ratte und erhöht die zirkulatorische Resistenz. In höheren Dosen von sogar 1.0, 0.1 E/kg beeinflusst Vasopressin Minutenvolumen und Zirkulation anderer Organe nicht.  相似文献   

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用原位聚合法制备了Sr0.7La0.15Ce0.15Fe11.7Zn0.3O19铁氧体/聚苯胺(PAn)复合材料。采用X射线衍射(XRD)、扫描电子显微镜(SEM)对样品的结构、微观表面形貌和粒子大小进行了表征,用微波矢量网络分析仪测量样品在2~12.4GHZ频率范围内复介电常数和复磁导率,根据测量数据计算微波反射率R与频率f的关系。研究结果表明:PAn包覆于掺杂锶铁氧体表面,PAn/Sr0.7La0.15Ce0.15Fe11.7Zn0.3O19复合材料具有良好的吸波性能,随着掺杂锶铁氧体含量的增加,微波吸收匹配厚度和吸收带宽发生变化:当Sr0.7La0.15Ce0.15Fe11.7Zn0.3O19聚合质量比为40%时,最佳匹配厚度为2.6mm,吸收峰值接近-40dB,峰值频率高于12.4GHz,大于10dB吸收带宽预计达到55GHz。  相似文献   

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Summary I.p. (±)N-n-propyl-nor-apomorphine HCl (NPA) influences copulatory behavior of vigorous adult male rats in the same ways as apomorphine, i.e., it reduces the latency to ejaculation as well as mount and intromission frequency. Furthermore, NPA administered to impotent male rats restores normal mating behavior in some of them.  相似文献   

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Zusammenfassung Der histologische Bau der Netzhaut vonPomatoschistus microps, insbesondere der Sehzellen in Hell- und Dunkelstellung, wurde untersucht. Die Zapfen sind gestaffelt und bilden ein regelmässiges Mosaik: Reihen von Zwillingszapfen alternieren mit Reihen von Einzelzapfen. Die Aussenglieder der Zwillingszapfen unterscheiden sich färberisch voneinander und sind ihrerseits regelmässig in das Mosaik eingeordnet.  相似文献   

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Riassunto Gli estratti metanolici di organo ipobranchiale diThais (purpura)haemastoma contengono cospicui quantitativi di un nuovo estere della colina, la diidromurexina o imidazolpropionilcolina. La base è localizzata esclusivamente nella striscia mediana giallastra dell'organo ipobranchiale, ove può raggiungere concentrazioni dell'ordine di 15–17 mg per g di tessuto fresco.

Supported by grants from the Consiglio Nazionale delle Ricerche, Roma.  相似文献   

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Zusammenfassung Saccharose und Glucose unterbinden die von schwachem Licht erzeugte negativ geotropische Kurvatur von Bermudagrasausläufern. Gibberellinsäure erzeugt eine Umkehrung dieses hemmenden Effekts.  相似文献   

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