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31.
Zusammenfassung Auf dem Prinzip der Komparationstitration wird eine schnelle oszillographische Methode für quantitative Adeninbestimmung in saurem Hydrolysat der RNS entwickelt.  相似文献   
32.
Zusammenfassung Bei Ratten, die eine besondere Diät erhielten, wurden Lungenveränderungen festgestellt. Bei Verfütterung von Bohnen (Phaseolus vulgaris) kam es zu emphysemähnlichen Veränderungen, welche funktionell und histologisch festgestellt wurden.  相似文献   
33.
Summary The influence of gaseous 1% sulphur dioxide during 24, 48, 72 and 96 h on saccharide and amino acid content, has been studied on 14–15-day old green and etiolated pea seedlings. In roots and shoots of intoxicated seedlings of both sorts, there was found a marked decrease of sucrose and a marked increase of glucose and fructose content, most probably as a consequence of disturbed sucrose biosynthesis. In cotyledons, roots and shoots there was also found an increase of alanine and a decrease of glutamic acid content.  相似文献   
34.
Summary The influence of thed,l-Methioninesulphoximine on the nitrogen metabolism of germinating seeds has been studied on peas. It has been shown thatd,l-Methioninesulphoximine, even at low concentrations, inhibited the germination of seeds and produced a decrease of growth of the roots. The inhibited germinating seeds contained less non-protein-nitrogen and less asparagine than the control plants. On the basis of the experimental results,d,l-Methioninesulphoximine could be considered as an inhibitor of proteolysis.  相似文献   
35.
36.
X-ray crystallography provides the vast majority of macromolecular structures, but the success of the method relies on growing crystals of sufficient size. In conventional measurements, the necessary increase in X-ray dose to record data from crystals that are too small leads to extensive damage before a diffraction signal can be recorded. It is particularly challenging to obtain large, well-diffracting crystals of membrane proteins, for which fewer than 300 unique structures have been determined despite their importance in all living cells. Here we present a method for structure determination where single-crystal X-ray diffraction 'snapshots' are collected from a fully hydrated stream of nanocrystals using femtosecond pulses from a hard-X-ray free-electron laser, the Linac Coherent Light Source. We prove this concept with nanocrystals of photosystem I, one of the largest membrane protein complexes. More than 3,000,000 diffraction patterns were collected in this study, and a three-dimensional data set was assembled from individual photosystem I nanocrystals (~200?nm to 2?μm in size). We mitigate the problem of radiation damage in crystallography by using pulses briefer than the timescale of most damage processes. This offers a new approach to structure determination of macromolecules that do not yield crystals of sufficient size for studies using conventional radiation sources or are particularly sensitive to radiation damage.  相似文献   
37.
Immunoadjuvant activity of synthetic N-acetyl muramyl dipeptide   总被引:1,自引:0,他引:1  
Summary The administration of phosphatidyl choline/cholesterol liposomes with entrapped N-acetyl muramyl dipeptide induced in guinea-pigs the development of delayed hypersensitivity to ovalbumin.  相似文献   
38.
Dendrobaena veneta is one of the most widely used compost worms now distributed all over Europe and has been described under several synonymous names. Besides the typical stripy red specimens, another form bearing pinkish pigmentation also exists, mostly found in natural habitats in the East Mediterranean. Here we provide the first integrative taxonomic analysis of D. veneta, including some closely related species. Both the morphological and molecular results highly support the resurrection of D. succinta, a former synonym of D. veneta. In addition, we describe a peculiar new species, D. karacadagi sp. n. from Anatolia, and prove the highly homoplasious character of the cross section of the longitudinal musculature.

urn:lsid:zoobank.org:pub:336D3F7A-AEA1-465B-9096-03070C761A6A  相似文献   

39.
Summary In plants of theBrassica oleracea species contaminated with S36O2, incorporation of radioactive sulphur into glucosinolate glucobrassicin has been found. The label is present also in the isothiocyanate group of glucobrassicin, which by decomposition under the action of myrosinase liberates labelled thiocyanate.  相似文献   
40.
Zusammenfassung Mitochondrienaggregate, die durch mitochondriale Imprägnation in der Oliva inferior der Katze gefunden wurden, bestehen elektronenmikroskopisch aus mehreren dendritischen und mehreren präsynaptischen Elementen. Diese bilden multiple axodendritische Synapsen, gehören also zur Gruppe der Komplexsynapsen.

With a grant of the Alexander-von-Humboldt-Stiftung.  相似文献   
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