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Curt Koßwig 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1932,4(1):22-32
Ohne Zusammenfassung 相似文献
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Elžbieta Milewska-Pawliczuk 《Biologia Plantarum》1987,29(4):295-298
Six thousand anthers ofSecale cereale cv. Dańkowskie Zlote and inbred lines L214 L215 and L258c/5, in the uninuclear microspore were cultured over a period of
three months on Murashige and Skoog nutrient medium supplemented with IAA (1–2μg1−1), kinetin (0.2 to (1.0μg1−1) and 2,4-D (0.5–2.0μg1−1). First divisions of microspore were observed after 7 days. In the course of 10 weeks, 4 albino tic embryos at the cotyledon
stage were observed that died away in the course of further culture. The course of androgenesis was regular in inbred lines
and irregular in rye cv. Dańkowskie Ziote. The efficiency of androgenesis and the amount of observed globular structures in
anthers were also dependent on the genetic potency of the material. Inbred lines did not show any greater viability of embryos. 相似文献
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Y C Kong W M Keung T T Yip K M Ko S W Tsao M H Ng 《Comparative biochemistry and physiology. B, Comparative biochemistry》1987,87(2):221-226
1. An epidermal growth factor (EGF)-like activity was detected and partially purified from swiftlet's nest extract. 2. The partially purified EGF-like activity was able to (a) generate competitive binding curves parallel to the standard curves in radioreceptor assay and (b) stimulate thymidine incorporation in quiescent culture of 3T3 fibroblasts and the latter activity can be suppressed by mouse EGF antibody. 3. Partial characterization of the EGF-like activity in terms of pI, molecular weight and its behavior on gel filtration column suggest that it bears similar physical properties to the EGFs isolated from the mouse and the shrew. 相似文献
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Hideki Takahashi Ko Shimamoto Yoshio Ehara 《Molecular & general genetics : MGG》1989,216(2-3):188-194
Summary In order to study possible functions of the inclusion body matrix protein (IBMP) encoded by gene VI of cauliflower mosaic virus (CaMV), the XbaI fragment containing the gene VI of a Japanese strain of CaMV (CaMV S-Japan) was transferred to tobacco plants by Ti mediated transformation. Eight out of 18 kanamycin resistant plants (40%) expressed detectable levels of IBMP. Those transgenic plants expressing IBMP produced leaves with light green color, and their growth was suppressed as compared with control plants. Symptom-like necrotic spots also appeared on the leaves and stems of the mature transgenic plants. Furthermore, in these transgenic plants, pathogenesis-related proteins 1a, 1b and 1c were highly expressed and the activity of 1,3--glucanase was increased up to eightfold. From these results, we concluded that expression of the IBMP is associated with symptom development. 相似文献