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Summary Colchicine induced tetraploid jute plants were shorter than their diploid counterparts. C2 tetraploid plants became taller than C1 plants. Leaves were larger in size and with higher breadth/length ratios compared to those of diploids. Stomata were bigger than those in diploid leaves but their frequency was less in tetraploid leaves. Tetraploid flowers were bigger than the diploids and bore a reduced number of stamens. Tetraploid pollen grains were larger but the percentage of sterility in them was more than that of the diploids. Fewer fruits with a reduced number of seeds were formed in tetraploid plants. They usually were shorter but wider than diploid fruits. Tetraploid seeds were larger and heavier. C2 tetraploid plants bore more fruits with an increased number of seeds than C1 plants. Breadth of individual fibres increased but length remained unchanged.The paper was read at the Eighth Pakistan Science Conference held at Dacca, 1956. 相似文献
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Vallack Harry W. Cinderby Steve Kuylenstierna Johan C.I. Heaps Charles 《Water, air, and soil pollution》2001,130(1-4):217-222
Water, Air, &; Soil Pollution - Top-down inventories of anthropogenic SO2 and NOx emissions were compiled for 1995 for developing country regions. Regional emission factors were used to generate... 相似文献
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Recent studies have stressed the importance of epithelial hyperproliferation in the pathogenesis of early lesions (parakeratotic hyperkeratosis) of the porcine gastric pars oesophagea (PO). In this study, immunohistochemical staining with Ki67 (clone MIB1) and AgNOR proteins silver staining were used to evaluate, by means of image analysis, cell proliferation in normal and parakeratotic (parakeratotic hyperkeratosis) epithelia of the PO. Apoptotic activity was also assessed with the TUNEL assay and compared with cell proliferative parameters. Early lesions of the PO were characterised by a significant increase in epithelial proliferative activity while there was no difference in the apoptotic activity between normal and parakeratotic epithelia.Our data confirm the hyperproliferative nature of epithelial changes preceding degeneration and erosion/ulcer of the PO and suggest that an underlying feature of gastric ulcers in pigs is an imbalance between cell proliferation and programmed cell death. 相似文献
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