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831.
The primary structure of the glycan moiety of pseudomurein from Methanobacterium thermoautotrophicum 总被引:5,自引:0,他引:5
H K?nig O Kandler M Jensen E T Rietschel 《Hoppe-Seyler's Zeitschrift für physiologische Chemie》1983,364(6):627-636
After treatment of isolated cells walls of Methanobacterium thermoautotrophicum with sodium hydroxide or anhydrous hydrazine, water soluble glycan strands were obtained. These consisted of alternating (beta 1-3)-linked D-glucosamine and (alpha 1-3)-linked L-talosaminuronic acid residues and their length was about 25 disaccharides. Some of the L-talosaminuronic acid residues remained linked to either glutamic acid or the peptides N-gamma-glutamylalanine and N epsilon-(gamma-glutamylalanyl)lysine, indicating that the peptide moiety of pseudomurein is bound to the carboxyl group of talosaminuronic acid via the amino group of glutamic acid. 相似文献
832.
The present paper deals with the discovery of the warble-fly Oestromyia leporina in the surrounding of Giessen. The behaviour of the flies in the field is described; in particular the behaviour of both sexes before and during mating and of the female during the oviposition period is described for the first time. The relations between host and parasite are explained as well as the development from third-instar larvae into the puparaium and then into the imago. By further experiments it is attempted to find out the factors causing the long time of ten months' quiescence in the puparium. The range of hosts is tested by natural and experimental infections' furthermore it is discussed if the present findings can be applied to other populations of the same warble-flies in far-off regions. 相似文献
833.
834.
Marcella Camici Carlo Fini Pier Luigi Ipata 《Biochimica et Biophysica Acta (BBA)/General Subjects》1985,840(1):6-12
5′-Nucleotidase (EC 3.1.3.5) has been solubilized and purified 1200-fold from guinea-pig skeletal muscle, to a specific activity of 40 U/mg protein. The purified enzyme yields a single protein band on polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. Guinea-pig skeletal muscle 5′-nucleotidase is extremely sensitive to inhibition by nucleoside di- and triphosphates. The inhibition is of the competitive type, and can be reversed only by strong excess of Mg2+. Nucleoside diphosphates are more powerful inhibitors than nucleoside triphosphates. The Ki values for ADP and ATP are 0.036 and 0.28 μM, respectively. The purified enzyme does not require exogenous cations for maximal activity and is inhibited by EDTA. This inhibition is reversed by divalent cations. This indicates that the enzyme contains a tightly bound metal cation. 相似文献
835.
Toni-Kim Clarke Jens Treutlein Ulrich S Zimmermann Falk Kiefer Markus H Skowronek Marcella Rietschel Karl Mann Gunter Schumann 《Addiction biology》2008,13(1):1-14
Genetic and environmental influences are both known to be causal factors in the development and maintenance of substance abuse disorders. This review aims to focus on the contributions of genetic and environmental research to the understanding of alcoholism and how gene-environment interactions result in a variety of addiction phenotypes. Gene-environment interactions have been reviewed by focusing on one of the most relevant environmental risk factors for alcoholism, stress. This is examined in more detail by reviewing the functioning of the hypothalamic-pituitary-adrenal (HPA) axis and its genetic and molecular components in this disorder. Recent evidence from animal and human studies have shown that the effects of stress on alcohol drinking are mediated by core HPA axis genes and are associated with genetic variations in those genes. The findings of the studies discussed here suggest that the collaborations of neuroscience, psychobiology and molecular genetics provide a promising framework to elucidate the exact mechanisms of gene-environment interactions as seen to convene upon the HPA axis and effect phenotypes of addiction. 相似文献
836.
837.
Himanshu Matalia Jyoti Matalia Anchana Pisharody Yash Patel Nandini Chinnappaiah Marcella Salomao Renato Ambrosio Abhijit Sinha Roy 《Journal of biophotonics》2020,13(10)
The purpose of this study was to assess unique corneal tomographic parameters of allergic eye disease (AED) using optical coherence tomography (OCT) and artificial intelligence (AI). A total of 57 eyes diagnosed with AED were included. The curvature and aberrations of the air‐epithelium (A‐E) and epithelium‐Bowman's layer (E‐B) interfaces were calculated. Random forest AI models were built combing this data with the parameters of healthy, forme fruste keratoconus (FFKC) and KC eyes. The AI models were cross‐validated with 3‐fold random sampling. Each model was limited to 10 trees. The AI model incorporating both A‐E and E‐B parameters provided the best classification of AED eyes (area under the curve = 0.958, sensitivity = 80.7%, specificity = 98.5%, precision = 88.2%). Further, the E‐B interface parameters provided the highest information gain in the AI model. A few AED eyes (n = 9) had tomography parameters similar to FFKC and KC eyes and may be at risk of progression to KC. 相似文献
838.
Hans Georg Rietschel 《Cell and tissue research》1933,19(4):636-652
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Mit 3 Textabbildungen. 相似文献
839.
Anna Alvarez-Guaita Satish Patel Koini Lim Afreen Haider Liang Dong Olivia J. Conway Marcella K.L. Ma Davide Chiarugi Vladimir Saudek Stephen O’Rahilly David B. Savage 《Cell reports》2021,34(10):108810
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840.