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1.
A search for differences due to ANS staining (hydrophobia), Con A and PNA binding capacity, and birefringence was carried out on stratified epithelia of rat skin and human breast cells (HBC) in culture. Microfluorimetric measurements confirm that the ANS fluorescence of the stratum corneum from adults is higher than that of newborns. HBC exhibited an unexpected deep ANS-fluorescence. Differences in the binding capacity of the epithelial layers to Con A and PNA were detected with advancing age. Retardation measurements revealed that the form birefringence of the stratum corneum is higher in adult animals specially as revealed by the fact that its form birefringence curve branch from n = 1.414 to n = 1.479 is steeper, i.e. depict higher values. The strong birefringence of the cytoplasmic tonofilaments presented by cultured human breast cells was considered an unexpected finding and attributed to changes that the cells underwent following the in vitro conditions. 相似文献
2.
August Neilreich 《Plant Systematics and Evolution》1860,10(4):115-118
Ohne Zusammenfassung 相似文献
3.
Laura Miralles Santiago Lens Antonio Rodríguez-Folgar Manuel Carrillo Vidal Martín Bjarni Mikkelsen Eva Garcia-Vazquez 《PloS one》2013,8(8)
Visual species identification of cetacean strandings is difficult, especially when dead specimens are degraded and/or species are morphologically similar. The two recognised pilot whale species (Globicephala melas and Globicephala macrorhynchus) are sympatric in the North Atlantic Ocean. These species are very similar in external appearance and their morphometric characteristics partially overlap; thus visual identification is not always reliable. Genetic species identification ensures correct identification of specimens. Here we have employed one mitochondrial (D-Loop region) and eight nuclear loci (microsatellites) as genetic markers to identify six stranded pilot whales found in Galicia (Northwest Spain), one of them of ambiguous phenotype. DNA analyses yielded positive amplification of all loci and enabled species identification. Nuclear microsatellite DNA genotypes revealed mixed ancestry for one individual, identified as a post-F1 interspecific hybrid employing two different Bayesian methods. From the mitochondrial sequence the maternal species was Globicephala melas. This is the first hybrid documented between Globicephala melas and G. macrorhynchus, and the first post-F1 hybrid genetically identified between cetaceans, revealing interspecific genetic introgression in marine mammals. We propose to add nuclear loci to genetic databases for cetacean species identification in order to detect hybrid individuals. 相似文献
4.
Zusammenfassung Es wurde versucht, zwei physiologisch durch die Oxalsäurebildung und die dadurch beeinflußte Richtung der Autolyse verschiedene Rassen von Aspergillus niger ineinander überzuführen. Dies gelang durch Einwirkung von Trocknen bzw. Erhitzen der Sporen und durch Passage über Tannin- und Oxalsäurelösung.Der Übergang der Rasse Göttingen neu (viel Oxalsäure, saure, helle Autolyse) in die Rasse Göttingen alt (wenig Oxalsäure, neutrale bzw. alkalische, dunkle Autolyse) ging bedeutend leichter als umgekehrt.Durch Oxalsäurepassage wird die Rasse Göttingen alt stärker in der Richtung der sauren, die Rasse Göttingen neu stärker in der Richtung der neutralen Autolyse beeinflußt.Die jeweiligen Veränderungen erwiesen sich drei bis acht Generationen, soweit untersucht, konstant.Mit Hilfe ähnlicher Methoden dürften die Veränderungen bei diesem Pilz der experimentellen Analyse zugänglich werden.Kurzer Auszug aus der Dissertation von Paul Hugo Kreutzmann, Untersuchungen über die Variabilität von Aspergillus niger. Göttingen 1935. 相似文献
5.
August Kanitz 《Plant Systematics and Evolution》1872,22(5):162-163
Ohne Zusammenfassung 相似文献
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8.
Robert L. Brownell Jr. Lloyd T. Findley Omar Vidal Alejandro Robles Silvia Manzanilla N 《Marine Mammal Science》1987,3(1):22-30
The vaquita, Phocoena sinus , is a porpoise in the family Phocoenidae that lives only in the Gulf of California. The external appearance of P. sinus was unknown until 13 fresh specimens were recently examined. The most obvious morphological feature distinguishing P. sinus from its two congeners is the proportionately higher dorsal fin. The most striking features of the pigmentation pattern are the large black eye patches and the black upper and lower lip patches. In both areas, the pigmentation contrasts sharply with the surrounding light gray coloration. The total lengths of the specimens ranged from 70.3 cm (a neonate) to 143.5 cm (an adult female). 相似文献
9.
S Baláz E Sturdík J Augustín D Ilavsky D Végh L Stibrányi J Kovác 《Chemico-biological interactions》1987,63(2):195-206
Inhibitory effects of 35 2-furylethylenes, non-specific alkylating agents, on glycolysis in a respiratory mutant of Saccharomyces cerevisiae were correlated with their 1-octanol/water partition coefficients and the rate constants for reaction with 2-mercaptoacetic acid using physiologically based models. The simplest model explaining the data satisfactorily consists of two-step drug-receptor interaction involving reversible formation of a structurally non-specific non-covalent complex stabilized later covalently. The concentration of the free drug in the receptor surroundings was related to its initial concentration in external medium via a simple form of a disposition function constructed on the basis of time hierarchy of passive membrane transport, non-covalent binding to cell constituents and metabolic inactivation of the drug. 相似文献
10.
Human elongation factor 1α: a polymorphic and conserved multigene family with multiple chromosomal localizations 总被引:1,自引:0,他引:1