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1.
Kel Cook  D. Lee Taylor 《Biotropica》2023,55(1):268-276
Epiphytes, which grow on other plants for support, make up a large portion of Earth's plant diversity. Like other plants, their surfaces and interiors are colonized by diverse assemblages of fungi that can benefit their hosts by increasing tolerance for abiotic stressors and resistance to disease or harm them as pathogens. Fungal communities associated with epiphytic plants and the processes that structure these communities are poorly known. To address this, we sampled seven epiphytic seedless plant taxa in a Costa Rican rainforest and examined the effects of host identity and microhabitat on external and endophytic fungal communities. We found low host specificity for both external and endophytic fungi and weak differentiation between epiphytic and neighboring epilithic plant hosts. High turnover in fungi within and between hosts and habitats reveals that epiphytic plant-associated fungal communities are highly diverse and suggests that they are structured by stochastic processes.  相似文献   
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Previous classifications of malignant non-Hodgkin lymphomas (nHL) are based on morphological and histological-cytological findings. The rapid development of immunology, the application of immunocytological, cytochemical and electromicroscopic methods led to new classifications of nHL based on immunology. They are founded on the idea that the prevailing cells of nHL correspond to a cell type from the differentiation line of lymphocytes. Thus, a distinction can be made between malignant lymphomas (ml) of stem, B and T-cells; the more frequently occurring lymphomas originating from B-cells are represented by chronic lymphatic leukaemia originating from B1-cells, by ml of follicular genesis (centrocytes, centroblastic-centrocytic ml, centroblasts) and by ml synthesizing and releasing immunoglobulins (immunocytoma, immunoblastoma). The type formerly called "reticulosarcoma" (histocytic ml) could be identified to be an immature, Ig synthesizing ml (immunoblastloma) in most cases. The new classification enables a more extensive differentiation and a better prognostic statement to be made than previous ones. The new units of disease can be diagnosed in most cases with light microscopic routine methods, although borderline cases and unclassifiable ml may occur.  相似文献   
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The purpose of the present study is to investigate whether distribution patterns of the maximum fingertip force in all directions from 0 deg to 360 deg around the index fingertip are the same among subjects. Distributions of the maximum index fingertip force were measured at four finger postures for five subjects (healthy males, ages 21 to 25). It became apparent that distribution patterns of the fingertip force were very similar among subjects, through the application of an analysis of variance (level of significance: 5%) to the measurement results. In the production of the maximum fingertip force, Valero-Cuevas et al. [1998, 2000] reported that patterns of control signals for driving muscle forces were common among subjects. The results of the present study indicate that patterns of maximum fingertip force are also similar among subjects. Therefore, the possibility is high that the static transfer characteristic for index fingers from input (i.e., control signals to muscles) to output (ie., the maximum fingertip force) is also common among subjects.  相似文献   
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