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1.
Summary The lamellar system of chloroplasts consists of close double lamellae. In electronphotomicrographs, the walls of two adjacent double lamellae can be seen as one thick lamella. Because of this, the lamellae in the inner portion of a lamellar packet appear about twice as thick as those at the boundary of the packet and, in chloroplasts that contain grana, the granalamellae appear twice as thick as the stromalamellae.

Mit Unterstützung der Deutschen Forschungsgemeinschaft.  相似文献   

2.
Summary Herpes corneæ simplex (febrilis) is a virus disease. In 1942 the author found out that the purely epithelial forms of Herpes corneæ are cured on an average within four days, if the patients took 4–5 milligrams of «Gynergen Sandoz» (Ergotamin-tartrate Stoll) a day. According to the newest observations fresh Herpes corneæ can also be cured through rinsing with a solution of 0.5 mg of Gynergen (2 cm3 a day).The development of the Herpes disease and its cure is a chemical process of the cells, which, according to the author, is influenced by Gynergen. — Ergotamin is won out ofsecale cornutum, which owes its origin to the fungusClaviceps purpurea. This fungus together with thePenicillium notatum belongs to theAscomycetes group. Both are biologically related and their substance has chemical points of contact. — With respect to bacteria, Penicillin is antibiotic, the author presumes antibiotical properties against Herpes in Ergotamin (Gynergen Sandoz), the study of which he suggests should be gone into more thoroughly. With two different viruses Gynergen Sandoz has been known to bring about a cure in many cases: namely Herpes zoster ophthalmicus, and Herpes corneæ simplex (febrilis).  相似文献   

3.
Summary The hematic yolk precursor — vitellogenin — has been identified immunochemically in the serum of estrogenized females of the newtTriturus cristatus by employing an antiserum prepared against yolk proteins.  相似文献   

4.
Summary C. auronitens has 26 autosomes (2n), from which one pair — calledA-chromosomes — is relatively long.A-chromosomes consist of an euchromatic and a heterochromatic arm. In 63% of the individuals, theA-chromosomes are intraindividually anisomorph with regard to the length of their heterochromatic arm. According to its length, this arm shows 0–3 secondary constrictions. Hence there are at least 4 different forms of theA-chromosome.  相似文献   

5.
Philip Kitcher's The Advancement of Science sets out, programmatically, a new naturalistic view of science as a process of building consensus practices. Detailed historical case studies—centrally, the Darwinian revolutio—are intended to support this view. I argue that Kitcher's expositions in fact support a more conservative view, that I dub ‘Legend Naturalism’. Using four historical examples which increasingly challenge Kitcher's discussions, I show that neither Legend Naturalism, nor the less conservative programmatic view, gives an adequate account of scientific progress. I argue for a naturalism that is more informed by psychology and a normative account that is both more social and less realist than the views articulated in The Advancement of Science.  相似文献   

6.
During the long eighteenth century, boundaries between theology and natural philosophy, between imaginary and factual travel narratives, between fiction and social commentary, were far more fluid than they are today. To explore these relationships, this paper links Mary Shelley’s Frankenstein—a book often hailed as the first science fiction novel—to two earlier works which are now less well known: Edmond Halley’s article about terrestrial magnetism, in which he suggested that God had created inhabited illuminated cavities inside the earth; and a satirical fantasy voyage written by the Danish author Ludvig Holberg, but published anonymously as Niels Klim’s journey to the underground and immediately translated into many languages. Attention is focussed on how the ambiguous presentation of these and other texts blurs any straightforward classification of genres. The aim of examining these writers together is not to search for direct mappings from one project to another, but instead to introduce Holberg’s unfamiliar yet important book and also to cast new light on Frankenstein, one of England’s most famous works of literature.  相似文献   

7.
Summary For a convex body in three dimensions letV be the volume,F the surface area, andM the total mean curvature.TheBrunn-Minkowski theory gives the following well-known result: Among all the convex bodies withV andF fixed the spherical cap-body gives the maximum ofM.—The question regarding the minimum ofM has not yet been solved for the general case.—The authors prove that the minimum ofM is given by the symmetrical spherical zone, if we restrict our investigation to bodies of revolution.  相似文献   

8.
Summary Pieces of the hind legs of freshly moltedBlaberus craniifer adults were cultivated in vitro. The deposition of multilamellate and circadian-like layered endocuticle was observed. In multilamellate cuticle, the number of double lamellae was frequently much greater than the number of days in culture. In circadian-like layered cuticle, the number of double layers corresponded to the numbers of days in culture, or it was smaller.I am indebted to Mrs Hassenrück, for excellent assistance. — Supported by the Deutsche Forschungsgemeinschaft (We 389/12-2).  相似文献   

9.
In recent papers, Zurek [(2005). Probabilities from entanglement, Born's rule pk=|ψk|2 from entanglement. Physical Review A, 71, 052105] has objected to the decision-theoretic approach of Deutsch [(1999) Quantum theory of probability and decisions. Proceedings of the Royal Society of London A, 455, 3129–3137] and Wallace [(2003). Everettian rationality: defending Deutsch's approach to probability in the Everett interpretation. Studies in History and Philosophy of Modern Physics, 34, 415–438] to deriving the Born rule for quantum probabilities on the grounds that it courts circularity. Deutsch and Wallace assume that the many worlds theory is true and that decoherence gives rise to a preferred basis. However, decoherence arguments use the reduced density matrix, which relies upon the partial trace and hence upon the Born rule for its validity. Using the Heisenberg picture and quantum Darwinism—the notion that classical information is quantum information that can proliferate in the environment pioneered in Ollivier et al. [(2004). Objective properties from subjective quantum states: Environment as a witness. Physical Review Letters, 93, 220401 and (2005). Environment as a witness: Selective proliferation of information and emergence of objectivity in a quantum universe. Physical Review A, 72, 042113]—I show that measurement interactions between two systems only create correlations between a specific set of commuting observables of system 1 and a specific set of commuting observables of system 2. This argument picks out a unique basis in which information flows in the correlations between those sets of commuting observables. I then derive the Born rule for both pure and mixed states and answer some other criticisms of the decision theoretic approach to quantum probability.  相似文献   

10.
    
Summary Oxygen evolution of isolated chloroplasts ofImperata cylindrica is half inhibited by 10–6 M Simazin, a herbicide which is unable to kill this resistant tropical weed.  相似文献   

11.
Summary For the isolation of chloroplasts in non-aqueous media the following organic solvents are suitable: pentane, hexane, heptane, petroleum ether and carbon tetrachloride. These solvents cause a minimum loss of lipids.The loss of lipids and some lipid components of frozendried and ground shoots fromElodea canadensis during the isolation of chloroplasts in non-aqueous media (petroleum ether b. r. 60–80°C and petroleum ether-carbon tetrachloride mixtures) is reported.  相似文献   

12.
Summary Reserpinine, a minor alkaloid ofRauwolfia serpentina Benth. accompanying Reserpine, has been isolated, and its structural formula is proposed.

10. Mitteilung über Rauwolfia Alkaloide. — 9. Mitteilung sieheF. Bader, D. F. Dickel undE. Schlittler, Amer. Soc.76 (1954) (im Druck).  相似文献   

13.
Summary Research during the last two decades has clearly pointed out that dramatic ecosystem changes have occured in lakes due to deposition of acid substances and decreased pH. Today a large number of lakes and running waters in Scandinavia are suffering biological damage with disappearing fish populations, overgrowth of the bottom by mosses and filamentous algae, reduced invertebrate fauna, increased transparency etc.—Of all documented biological changes the effect on macrophyte succession, in particular that ofSphagnum, is the most striking effect. Along with the growth of filamentous algae, these changes have brought about major shifts in the composition of the primary producers. The biomass in one lake was estimated to be 6.5 t (dry wt) corresponding to about 24 g m–2, the relevant proportions being 52% forSphagnum, 34% forLobelia and 15% forIsoetes. Percentage production in the whole lake is 54% forSphagnum, 29% forLobelia and 17% forIsoetes, which gives an estimated production of 2.9 t yr–1 or 9 g m–2 yr–1.Sphagnum is a recent flora element and its occurrence is related to the acidification of the lakes. The investigations also show that the growth ofLobelia is reduced in acid lakes compared to other oligotrophic lakes due to shading by the benthic mat of filamentous algae, detritus andSphagnum debris.—One can conclude that there are several quantitative and qualitative changes in the macrophyte community which are related to acidification. One can also conclude that liming of lakes cause elimination ofSphagnum and some increase in the production ofIsoetids.  相似文献   

14.
Zusammenfassung Es konnte gezeigt werden, dass beim HöhlenfischAnoptichthys — neben zahlreichen anderen degenerativen Genen — ein Gen für Albinismus vorkommt.  相似文献   

15.
Summary Tyramine enhanced the production of acetoin from pyruvate in rat liver homogenates. A stimulation of acetoin synthesis was only observed, when tyramine was oxidized during the incubation. Tyrosol (p-hydroxyphenylethanol) stimulated acetoin synthesis whereasp-hydroxyphenylacetic acid and ammonia were ineffective.

Mit Unterstützung des »Schweizerischen Nationalfonds» und der Firma F. Hoffmann-La Roche & Co. AG, Basel.

8. Mitteilung. 1. Mitt.:H. Thölen, F. Bigler undH. Staub, Path. Microbiol. (Basel)24, 262 (1961). — 2. Mitt.:F. Bigler, H. Thölen undH. Staub, Helv. physiol. Acta19, C 11 (1961). — 3. Mitt.:H. Thölen, F. Bigler undH. Staub, Exper.17, 359 (1961). — 4. Mitt.:F. Bigler, H. Thölen undH. Staub, Schweiz. med. Wschr.91, 1259 (1961). — 5. Mitt.:H. Thölen, F. Bigler, A. Heusler, W. Stauffacher undH. Staub, Exper.18, 454 (1962). — 6. Mitt.:F. Bigler, H. Thölen undH. Staub, Schweiz. med. Wschr.92, 746 (1962). — 7. Mitt.:F. Bigler, H. Thölen undH. Staub, in Vorbereitung.  相似文献   

16.
Summary Acetoin and 2, 3-butylene glycol in blood of renal and hepatic patients are raised, when consciousness is disturbed. There is no correlation between blood levels of acetoin and 2, 3-butylene glycol and the degree of impairment of consciousness. Simultaneous determinations of acetoin and 2, 3-butylene glycol in blood and cerebrospinal fluid show that alterations of the cerebral pyruvic acid metabolism are difficult to detect in circulating blood.

Mit Unterstützung des «Schweizerischen Nationalfonds» und der Firma F. Hoffmann-La Roche & Co., AG, Basel.

5. Mitteilung. — 1. Mitt.:H. Thölen, F. Bigler undH. Staub, Path. Microbiol.24, 262 (1961). — 2. Mitt.:F. Bigler, H. Thölen undH. Staub, Helv. physiol. Acta19, C11 (1961). — 3. Mitt.:H. Thölen, F. Bigler undH. Staub, Exper.17, 359 (1961). — 4. Mitt.:F. Bigler, H. Thölen undH. Staub, Schweiz. med. Wschr.91, 1259 (1961).  相似文献   

17.
Zusammenfassung Der Aufbau der Zahnhartsubstanz ist im Verlaufe ihrer Bildung durch mehrere Faktoren — u.a. Begleitionen, Texturvorlage (Proteinmatrix) — bestimmt. Der Einfluss des Carbonatgehalts wurde in diesem Zusammenhang besonders im Hinblick auf dessen kristallchemische Funktion bei der Zahnmineralisation (parakristalline Struktur des teilweise isomorph substituierten Apatitis) untersucht.

See preceding communication:H. Newesely andE. Hayek, Exper.19, 459 (1963).  相似文献   

18.
Zusammenfassung Es wird gezeigt, dass eine 2·10–12 molare Katalase-Lösung den durch Luftsauerstoff sowie durch ein Wasserstoffperoxid-lieferndes Cytostaticum bewirkten — nicht aber den durch zugesetztes Wasserstoff-peroxid verursachten — Abbau von Desoxyribonucleinsäure (DNS) wesentlich verstärkt. Mitsteigender Katalase-Konzentration wird dieser Effekt immer kleiner und verschwindet schliesslich. Im Falle des Cytostaticums wird der DNS-Abbau durch Katalase-Konzentrationen über 10–11 M/1 inhibitiert. Dieser Übergang von Katalyse zu Inhibition wird auf die Fähigkeit der Katalase zu peroxydatischer bzw. häminkatalytischer Wirkung einerseits und zu katalatischer Wirkung andererseits zurückgeführt, wobei mit steigender Katalase-Konzentration eine Verschiebung zugunsten der katalatischen Reaktion erfolgt.  相似文献   

19.
Zusammenfassung Kulturen von Hühnerherzfibroblasten wurden nach 10, 21 und 28 Tagenin vitro auf ihren Gehaltan Hydroxyprolin — einer wichtigen Aminosäure des Kollagens — untersucht. Nach 10, bzw. 21 Tagen ist eine signifikante, durch Prolinzugaben nicht beeinflussbare Vermehrung des zu 50% löslichen Hydroxyprolins feststellbar.

Kantonsspital, Chur.  相似文献   

20.
In this paper I inquire into Bogen and Woodward’s (1988) data/phenomena distinction, which in a similar way to Cartwright’s construal of the model of superconductivity (1995)—although in a different domain—argues for a ‘bottom-up’ construction of phenomena from data without the involvement of theory. I criticise Bogen and Woodward’s account by analysing their melting point of lead example in depth, which is usually cited in the literature to illustrate the data/phenomenon distinction. Yet, the main focus of this paper lies on Matthias Kaiser’s (1995) case study of the plate tectonic revolution, the most extensive case study that has been put forth to support the bottom-up construction of phenomena. On the basis of new historical evidence, which has been overlooked not only by Kaiser but also by the entire historical literature on the plate tectonic revolution, I demonstrate that phenomena are not constructed from the bottom-up but rather, admittedly counter-intuitively, from the top-down.  相似文献   

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