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141.
For estimation of growth, the efficiency of linked cross sectional scheme has been compared with pure longitudinal and cross sectional schemes. The relevant estimation theory has been developed and the expressions for the optimum estimators alongwith their variances have been derived. It has been observed that for estimation of growth, the linked cross-sectional scheme has been observed to be less efficient as compared to pure longitudinal scheme but more efficient than pure cross-sectional scheme. 相似文献
142.
Takahiro Ishii Tatsufumi Okino Yosuke Mino Hiroaki Tamiya Fuyuhiko Matsuda 《Plant Growth Regulation》2007,52(2):131-139
Starfish waste has been shown to be an effective compost material not only in the promotion of plant growth but also in terms
of having insecticidal activity. In the present study, plant growth regulation by chemicals from starfish was examined. The
aqueous fraction from a hot water extract of the starfish Asterias amurensis Lütken showed plant-growth activity, while the aqueous fraction from a methanol extract inhibited growth of Brassica campestris. The lipophilic fraction from the methanol extract also exhibited a plant growth-promoting effect. The active components
from each extract were identified. Asterubine from the hot water extract promoted plant growth. A ceramide from the lipophilic
fraction showed root growth promoting effect, and three glucocerebrosides had promotive effects on the entire plant. Asterosaponins
were identified as the main growth inhibitors in the aqueous fraction of the methanol extract. These active compounds from
starfish waste could be analyzed as potential plant growth regulators in agricultural applications in the future. 相似文献
143.
This editorial addresses the debate concerning the origin of adult nucleus pulposus cells in the light of profiling studies
by Minogue and colleagues. In their report of several marker genes that distinguish nucleus pulposus cells from other related
cell types, the authors provide novel insights into the notochordal nature of the former. Together with recently published
work, their work lends support to the view that all cells present within the nucleus pulposus are derived from the notochord.
Hence, the choice of an animal model for disc research should be based on considerations other than the cell loss and replacement
by non-notochordal cells. 相似文献
144.
145.
Kevin B. Potts 《Journal of Mammalian Evolution》2010,17(3):221-222
146.
147.
148.
Background
Arsenic contamination is widespread throughout the world and this toxic metalloid is known to cause cancers of organs such as liver, kidney, skin, and lung in human. In spite of a recent surge in arsenic related studies, we are still far from a comprehensive understanding of arsenic uptake, detoxification, and sequestration in plants. Crambe abyssinica, commonly known as 'abyssinian mustard', is a non-food, high biomass oil seed crop that is naturally tolerant to heavy metals. Moreover, it accumulates significantly higher levels of arsenic as compared to other species of the Brassicaceae family. Thus, C. abyssinica has great potential to be utilized as an ideal inedible crop for phytoremediation of heavy metals and metalloids. However, the mechanism of arsenic metabolism in higher plants, including C. abyssinica, remains elusive. 相似文献149.
A K Srivastava C Pandey K P Dwivedi V K Singh 《Indian journal of biochemistry & biophysics》1989,26(3):199-200
QSAR studies have been performed on the homologues of 3-triazines, using molecular connectivity index and van der Waal volume as structural parameters. The regression analysis has shown good correlation between antitumour activity and the two structural parameters. 相似文献
150.
Surendra Singh 《FEMS microbiology letters》1988,56(3):281-283
Abstract The utilization of urea was studied in the cyanobacterium Anabaena doliolum . The uptake of urea was unaltered in the presence of ammonium. The cells receiving ATP exogenously showed an induced level of urea-uptake as compared with the control cells. Urease inhibitor acetohydroxamic acid and hydroxyurea as well as glutamate analogue, MSO, did not affect the uptake of urea. These results suggest: (1) urea and ammonia have different uptake sites, (2) urea-uptake is an energy dependent process, and (3) during short-term experiments, urea uptake is not linked with the enzyme urease or the ammonium assimilating enzyme glutamine synthetase. 相似文献