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1.
DAX-1, an ‘antitestis’gene   总被引:2,自引:0,他引:2  
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2.
In Of Quadrature by Ordinates (1695), Isaac Newton tried two methods for obtaining the Newton–Cotes formulae. The first method is extrapolation and the second one is the method of undetermined coefficients using the quadrature of monomials. The first method provides $n$ -ordinate Newton–Cotes formulae only for cases in which $n=3,4$ and 5. However this method provides another important formulae if the ratios of errors are corrected. It is proved that the second method is correct and provides the Newton–Cotes formulae. Present significance of each of the methods is given.  相似文献   

3.
Summary The activity of D-lactate dehydrogenase in the foot of the snail,Helix pomatia, is closely correlated with time of year and mean daily temperature, and increases strikingly after the animals have been exposed to a nitrogen atmosphere for 24 h.I thank U. Platzer for technical assistance and D. Frank for help with the statistics. The investigation was supported by the Fonds zur Förderung der wissenschaftlichen Forschung in Österreich, project No. 1257 and 2919.  相似文献   

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Riassunto Gli autori hanno dimostrato che alcuni farmaci (p.e. la clorciclizina, la glutetimide, il fenaglicodolo, il fenobarbital, la clorpromazina, il cloretone ed altri), che posseggono una tardiva attività «inducente» di stimolo su enzimi microsomici epatici, attivi nel metabolismo di svariati farmaci, determinano invece una inibizione degli enzimi stessi quando vengano fatti agire direttamente.  相似文献   

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The near consensus in the secondary literature on Feyerabend is that his epistemological anarchism, characterized by the slogan ‘anything goes’, was not a positive proposal but the conclusion of a reductio argument against his opponents (Lloyd 1997; Staley 1999; Munévar 2000; Farrell 2003; Tsou 2003; Oberheim 2006; Roe 2009). This makes anarchism a mere criticism rather than a substantive position in its own right. In this paper, I argue that Feyerabend held anarchism as a positive thesis. Specifically, I present two possible interpretations of anarchism: one where anarchism is entailed by Feyerabend's radical view of pluralism and another where scientists must be ‘methodological opportunists’, which Feyerabend held simultaneously from at least 1970. I then consider how these positions fare against the more influential criticisms of anarchism (Nagel 1977; Worrall 1978; Godfrey-Smith 2003). I conclude by suggesting two avenues to constraining a literal interpretation of ‘anything goes’ on Feyerabendian grounds.  相似文献   

7.
Zusammenfassung Experimentell wurde die Wirkung von Prednison und Hydrocortisonacetat auf die Entwicklung des Fremdk?rpergranuloms an intakten und an thyreoid- und parathyreoidektomierten Tieren untersucht. Nach beidseitiger Thyreoidektomie konnte keine Unterdrückung der entwicklungshemmenden Effekte der Corticoide festgestellt werden.   相似文献   

8.
Summary By means of closed-loop-stripping and subsequent GC analyses the diel periodicity of release of (Z)-11-hexadecenyl acetate, (E)-8-dodecenyl acetate, and (Z)-9-tetradecenyl acetate, the main constituents of the respective sex pheromone blends ofMamestra brassicae, Cryptophlebia leucotreta andSpodoptera sunia females, was determined.Pheromones, 64. For the 63rd contribution we have taken from: Szöcs, G., Toth, M., Bestmann, H. J., Vostrowsky, O., Heath, R. R., and Tumlinson, J. H., Z. Naturforsch.42c (1987) 165; Pheromones, 62: Bestmann et al.13.  相似文献   

9.
The generation of reactive free radicals byChattonella antiqua (Red Tide), which may be a causative factor in fish death, has been demonstrated by electron spin resonance spectroscopy and a microelectrode technique. Electrochemical detection indicates that superoxide anions are produced as a primary product, and undergo further reactions during diffusion in glycocalyx to produce hydrogen, hydroxy-, and carbon-centered radicals which are detected by ESR as secondary products. It is proposed that these reactive radicals are responsible for the destruction of the mucous membranes of fish on exposure to Red Tide.  相似文献   

10.
Summary Fruit and leaf initiation by 26 trees representing five stranglerFicus species in the subgenusUrostigma were monitored for 5–8 years in a seasonal lowland forest of central Panamá. Individual trees of each species initiated fruit in synchronized crops. High variation in the number of crops, intervals between crops and dates of crop initiation indicate that these species, like species in the subgenusPharmacosycea, initiate fruit crops the year around. Nevertheless, mean crop initiation dates for four of five species fell within the four-month dry season. Similarly, all species produced new leaf flushes throughout the year, however, mean leaf flush dates of all species fell within the first three months of the dry season.  相似文献   

11.
Summary Tamoxifen is an anticancer drug widely used in the treatment of estrogen-dependent breast cancer. In hatchling alligators it acts as a pure antiestrogen in that it completely blocks the effect of estradiol-induced oviductal hypertrophy and completely blocks the estradiol-induced hepatic vitellogenin secretion. Paradoxically, when injected into alligator eggs incubated at 33°C, a temperature which would normally result in 100% male hatchlings, tamoxifen sex reverses the embryos into apparently normal female hatchlings.  相似文献   

12.
Summary The arming of normal peripheral blood leukocytes (PBL) by cytophilic antibody in the sera of prostatic cancer patients is suppressed by pretreatment of PBL with normal human seminal plasma (HuSP1). Suppression of cytophilic antibody by HuSP1 extends the spectrum of immunologic reactions on which SP1 has an immunosuppressive effect and may provide further insight into the possible role of SP1 in the natural history of prostatic cancer.  相似文献   

13.
P-glycoprotein (P-gp) is an active membrane transporter responsible for cell detoxification against numerous amphiphilic compounds, leading to multidrug resistance in tumor cells. It displays entangled connections with its membrane environment since it recognizes its substrates within the cytosolic leaflet and it also translocates some endogenous lipids to the exoplasmic leaflet. Regarding its relationships with membrane microdomains, ‘lipid rafts’, a literature analysis concludes that (i) P-gp also exists in rafts and non-raft membrane domains, depending on the cell considered, the experimental conditions and the method used to test it; (ii) cholesterol has a positive influence on P-gp function, and this may be a direct effect of the free cholesterol present in membrane or an indirect effect mediated by the cholesterol-enriched microdomains; (iii) when present in rafts, P-gp interacts with protein partners regulating its activity; (iv) P-gp is a lipid translocase that handles the raft-constituting lipids with particular efficiency, and it also influences membrane trafficking in the cell. Received 18 November 2005; received after revision 23 December 2005; accepted 12 January 2006  相似文献   

14.
The broad analysis made by Home and Watanabe of the development of physics in Australia during the period from 1914 to 1945 is generally accepted; however, details relating to the backgrounds of certain of these developments are questioned.  相似文献   

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