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Résumé Pendant l'hibernation, leStrophocheilus (Pulmoné, Mollusque) perd de l'eau, du sodium, du calciun, du magnésium, du soufre, du cuivre, du fer et des carbohydrates totaux, mais son taux de potassium et d'iode augmente. En état d'estivation, il y en a perte d'eau, de sodium, de magnésium, de cuivre, de fer et de carbohydrates totaux, mais accumulation de calcium.  相似文献   
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Summary Bunaphtide induces a blockade in the3H-norepinephrine uptake and retention in the isolated guinea-pig left atrium. However, this blockade does not seems to be related with the cardiodepressant effect of the drug.  相似文献   
86.
Carcinogenic nitrosamines formed by drug-nitrite interactions   总被引:3,自引:0,他引:3  
W Lijinsky  E Conrad  R Van de Bogart 《Nature》1972,239(5368):165-167
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87.
W W de Jong  L F Bernini 《Nature》1968,219(5161):1360-1362
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88.
Our Solar System was formed from a cloud of gas and dust. Most of the dust mass is contained in amorphous silicates, yet crystalline silicates are abundant throughout the Solar System, reflecting the thermal and chemical alteration of solids during planet formation. (Even primitive bodies such as comets contain crystalline silicates.) Little is known about the evolution of the dust that forms Earth-like planets. Here we report spatially resolved detections and compositional analyses of these building blocks in the innermost two astronomical units of three proto-planetary disks. We find the dust in these regions to be highly crystallized, more so than any other dust observed in young stars until now. In addition, the outer region of one star has equal amounts of pyroxene and olivine, whereas the inner regions are dominated by olivine. The spectral shape of the inner-disk spectra shows surprising similarity with Solar System comets. Radial-mixing models naturally explain this resemblance as well as the gradient in chemical composition. Our observations imply that silicates crystallize before any terrestrial planets are formed, consistent with the composition of meteorites in the Solar System.  相似文献   
89.
Standard considerations of philosophy of science are reformulated in psychological terms and arguments, suggesting a fundamental change in life perspective: subjective experiences or introspective data are subject to motivational biases and therefore not admitted as objective empirical facts in science, However, we never experience objects or events of the external world, i.e., so called objective facts, but exclusively subjective percepts or mental events. They are merely assumed to, but may or may not be accurate or distorted mental representations of objects or events of an external world. Accordingly, the latter are theoretical constructs, i.e., constructs of the fictitious but most successful predictive (implicit) theory, called external world, which seems to be constructed from regularities observed in mental events and serves as a reference fiction for, erroneously called empirical, tests of predictions of scientific theories.Relevant Publication: Micko, H.C.: 2001, Psychologie: Von der Geistes – zur Naturwissenschaft – und weiter wohin? Erkenntnistheoretische Erwägungen vor und nach dem Aufkommen des philosophischen Konstruktivismus. Ztschr. f. Psychologie, 209: 54–68.  相似文献   
90.
In the context of developing a safe genetic vaccination strategy we tested and studied globin-stabilized mRNA-based vaccination in mice. This vaccination strategy has the advantages of genetic vaccination (easy production, adaptability to any disease and inexpensive storage when lyophilized), but not the drawbacks of DNA vaccination (long-term uncontrolled expression of a transgene, possibility of integration into the host genome and possible induction of anti-DNA antibodies). We report here that injection of naked -globin untranslated region (UTR)-stabilized mRNA coding for -galactosidase is followed by detectable translation in vivo. In addition, we show that such a vaccination strategy primes a T helper 2 (Th2) type of response which can be enhanced and shifted to a Th1-type immune response by application of recombinant granulocyte/macrophage colony-stimulating factor 1 day after mRNA injection. Our data demonstrate that the administration of globin UTR-stabilized mRNA is a versatile vaccination strategy that can be manipulated to fit the requirement of antiviral, antibacterial or antitumor immunity.Received 14 June 2004; received after revision 19 July 2004; accepted 9 August 2004  相似文献   
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