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51.
Horst Drawert 《Protoplasma》1938,29(1):206-227
Ohne Zusammenfassung 相似文献
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The complex C60Pt[P(OPh)3]2 displays C60 ππ* intraligand bands in the UV-Vis region and a long-wavelength absorption at λmax = 770 nm which is assigned to a metal-to-ligand charge transfer (MLCT) transition from platinum to fullerene. The irradiation of the complex leads to the population of the reactive MLCT state and subsequently to the dissociation (C60Pt[P(OPh)3]2 → C60 + Pt[P(OPh)3]2) in the primary photochemical step. Product formation takes place by the interception of Pt[P(OPh)3]2 with suitable scavengers such as CHCl3 or O2. 相似文献
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Kai Voges Horst Bleckmann 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2011,197(8):827-837
We determined the receptive fields of midbrain lateral line units in goldfish, Carassius auratus, with a 50 Hz vibrating sphere placed at various azimuths and elevations alongside the fish and studied how responses were
affected by different directions of sphere vibration. The receptive fields of toral lateral line units, in contrast to those
of primary afferent nerve fibers, did not represent the pressure gradient pattern generated by a vibrating sphere. Thus, unlike
primary afferents, single toral lateral line units did not code for source location in their spatial discharge patterns. The
two-dimensional receptive fields were round, horizontally or vertically stretched, or complex. While some toral lateral line
units were sensitive to the direction of sphere vibration others were not. 相似文献
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Maurecilne Lemes da Silva Daniela Lopes Paim Pinto Miguel Pedro Guerra Eny Iochevet Segal Floh Cláudio Horst Bruckner Wagner Campos Otoni 《Plant Cell, Tissue and Organ Culture》2009,99(1):47-54
The objective of the present work was to induce somatic embryogenesis from zygotic embryos of Passiflora cincinnata Masters. Zygotic embryos formed calli on media with different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) and
4.5 μM benzyladenine (BA) after 30 days of in vitro culture. A concentration of 18.1 μM 2,4-D resulted in the largest number
of somatic embryos. Embryogenic calli were yellowish and friable, forming whitish proembryogenic masses. Morphologically,
embryogenic cells were small and had large nuclei and dense cytoplasm, whereas non-embryogenic cells were elongated, with
small nuclei and less dense cytoplasm. Calli cultured under white light on basal Murashige and Skoog’s medium with activated
charcoal produced embryos in all developmental stages. There were differences among the treatments, with some leading to the
production of calli with embryos and some only to callus formation. Some abnormalities were associated with somatic embryos,
including fused axes, fused cotyledons and polycotyledonary embryos. Production of secondary somatic embryos occurred in the
first cycle of primary embryo development. Secondary embryos differentiated from the surface of the protodermal layer of primary
embryos with intense cell proliferation, successive mitotic divisions in the initial phase of embryoid development, and a
vascular system formed with no connection to the parental tissue. This secondary embryogenic system of P. cincinnata is characterized by intense proliferation and maintenance of embryogenic competence after successive subcultures. This reproducible
protocol opens new prospects for massive propagation and is an alternative to the current organogenesis-based transformation
protocol. 相似文献
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