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Virchows Archiv B Cell Pathology - Lymphocyte-monocyte synergistic interaction in cooperative response to mitogens and antigens is well established. This paper describes a less known —...  相似文献   
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By means of one- and two-dimensional (cross) immunoelectrophoresis, immunoelectro-diffusion and radial immunodiffusion, about 20 antigens were detected in mitochondria of meristem, zone of elongation and mature cells, among which some were identified by zymographic methods. The differentiation of root cells is not accompanied by qualitative changes in antigenic spectra of mitochondria and changes in the ratio of antigens (including glutamate and malate dehydrogenases) suggest that mature mitochondria develop from preexisting ones by gradual quantitative changes which are due to different rate of synthesis of constituent proteins.  相似文献   
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The effect of lincocin (a plastid protein synthesis inhibitor) treatment on the greening process of bean (Phaseolus vulgaris L.) leaves have been studied. In comparison with control leaves treated ones had a decreased rate of chloroplast development. They had a marked chlorophyll deficiency and a decreased chlorophyll a/b ratio. Some long and short wavelength forms of chlorophyll a were lacking as evidenced from the absorption spectra at 25°C and the fluorescence spectra at 77°K. The –14CO2 fixation was inhibited by 80–90% in treated leaves. The fluorescence induced by the measuring light was greater in the treated leaves than in the control ones, and the kinetics of the decline of the relative fluorescence intensity were also different. Electron microscopic studies showed macrogranum-like structures and incomplete membrane vesicles in the treated plastids. After longer treatment a destruction of membranes was observed. The results indicate some structural and functional membrane deficiencies and instability of the membranes.  相似文献   
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Summary

The larval development of the ophiocomid ophiuroid Ophiomastix venosais described using SEM. The gastrula transforms into a uniformly ciliated early larva which progressively changes into a lecithotrophic late premetamorphic larva with a continuous bilateral ciliated band. This stage is short-lived and equivalent to a highly reduced ophiopluteus. Comparisons between O. venosa and other ophiuroid species whose development has been investigated suggest that, whatever the developmental mode (lecithotrophic or planktotrophic), a pluteus stage always occurs in ophiuroids with planktonic development. Two metamorphic stages were identified, the late metamorphic larva differing from the early one by the closure of the larval mouth. The appearance of the permanent mouth marks the end of the metamorphosis. The postlarva still possesses remnants of larval features. The transformation of the reduced ophiopluteus into a barrel-shaped metamorphic larva with transverse ciliated bands, a vitellaria larva, is followed. The possible occurrence of a unique type of metamorphic larva in non-brooding ophiuroids is discussed. Verification of this, however, needs further SEM investigations on metamorphic larva from species having “regular” planktotrophic development.  相似文献   
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MRI findings of 13 patients with soft tissue tumors (STT) are presented. There are were abnormalities, such as primary STTs of the hip in 5 patients, the back in 1, and the neck in 1, STT relapses of the hip in 2 and those of the back in 1. Two patients had chronic hip STT hematomas and 1 had hip STT metastatic melanoma. The diagnosis was verified in 11 cases (in 10 cases at surgery and 1 at needle biopsy). MRI makes it possible to define the accurate sizes of the tumor, its structure and relationship to its adjacent tissues, which is important in choosing at treatment policy, the type and scope of a surgical interventions.  相似文献   
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