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991.
Diosbulbin d and 8-epidiosbulbin e acetate,norclerodane diterpenoids from dioscorea bulbifera tubers
Robert D.H. Murray Zacarias D. Jorge Nurul H. Khan Mohammad Shahjahan Mohammad Quaisuddin 《Phytochemistry》1984,23(3):623-625
From tubers of Dioscorea buibifera L. var sativa a new 18-norclerodane diterpenoid, 8-epidiosbulbin E acetate, has been isolated, besides the previously known norditerpenoid, diosbulbin D, and its structure established by spectroscopic means. 相似文献
992.
Rhythmic up-down movements were studied in the lateral leaflets ofDesmodium gyrans (L.F.) DC. These were recorded with a video-computer system, whereby the digital video signals from a CCD camera were processed
with special software. Under control conditions (24°C and 0.1 nM cm-2 s-1 of stable, dim light), the average period of lateral leaflet movement was 3.5 min. In the presence of light stimuli (for
2 min), those leaflets always moved toward the light, regardless of where it was applied to any axial part of the pulvinus.
The strongest effect was manifested by a reduced amplitude of movement and, thus, a shortened period, which could be up to
~43% less under moderate light intensity (5 nM cm-2 s-2). Oscillations regained their original regularity over ~10 cycles after the light stimulus was removed. In addition, these
oscillations temporarily disappeared after long exposure (~10 min) under moderate light, or when the leaflets were quickly
exposed to a higher intensity (~12 nM cm-2s-1). Therefore, we have now demonstrated that light can affect physiological parameters that are involved in the control of
oscillations. 相似文献
993.
A simple and rapid flow-injection method is described for the determination of iodide, based on potassium permanganate chemiluminescence detection via oxidation of formaldehyde in aqueous hydrochloric acid. The calibration graph was linear over the range 1.0-12 x 10(-6) mol/L (r2 = 0.9955) with relative standard deviations (n = 4) in the range 1.0-3.5%. The detection limit (3sigma) was 1.0 x 10(-7) mol/L, with sample throughput of 120/h. The effect of interfering cations [Ca(II), Mg(II), Ni(II), Fe(II), Fe(III) and Pb(II)] and anions (Cl-, SO4(2-), PO4(3-), NO3-, NO2-, F- and SO3(2-)) were studied. The method was applied to iodized salt samples and the results obtained in the range 0.03 +/- 0.005 - 0.10 +/- 0.006 mg I/g were in reasonable agreement with the amount labelled. The method was statistically compared with the results obtained by titration; no significant disagreement at 95% confidence was observed. 相似文献
994.
Christopher J Lelliott Gema Medina-Gomez Natasa Petrovic Adrienn Kis Helena M Feldmann Mikael Bjursell Nadeene Parker Keira Curtis Mark Campbell Ping Hu Dongfang Zhang Sheldon E Litwin Vlad G Zaha Kimberly T Fountain Sihem Boudina Mercedes Jimenez-Linan Margaret Blount Miguel Lopez Aline Meirhaeghe Mohammad Bohlooly-Y Leonard Storlien Maria Strmstedt Michael Snaith Matej Orei
E. Dale Abel Barbara Cannon Antonio Vidal-Puig 《PLoS biology》2006,4(11)
995.
996.
997.
The Major Component of IκBα Proteolysis Occurs Independently of the Proteasome Pathway in Respiratory Syncytial Virus-Infected Pulmonary Epithelial Cells
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998.
The diagnostic and prognostic value of circulating microRNAs in coronary artery disease: A novel approach to disease diagnosis of stable CAD and acute coronary syndrome
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999.
1000.
Mohammad Firoze Quamar Sheikh Nawaz Ali Sundeep Kumar Pandita Yudhbir Singh 《Grana》2018,57(5):364-376
Twenty five surface samples/moss cushions were collected for palynological analysis from open areas of Reasi District, Jammu and Kashmir (India). These samples were used to investigate the relationships between extant vegetation and modern pollen spectra, which serve as modern analogue for the reliable ecological interpretation of fossil pollen records. The present vegetation in the region comprises tropical dry deciduous forests and subtropical pine forests with scattered stands of oak. The pollen analysis reveals that Pinus sp. (average 69% in the pollen assemblages), amongst the conifers, dominates the pollen rain, which can be attributed to its high pollen productivity and exceptional pollen dispersal efficiency. Cedrus sp. and Podocarpus sp. pollen contribute with an average of 16 and 5% to the total pollen rain. Other conifers such as Picea sp., Abies sp., Juniperus sp. and Tsuga sp., as well as broad-leaved taxa such as Quercus sp., Alnus sp., Betula sp., Carpinus sp., Corylus sp., Juglans sp., Ulmus sp., Salix sp., Elaeocarpus sp., Mallotus sp. and Aesculus sp., have lower averages of 1 to 4.5% in the total pollen rain which could be either due to their poor pollen dispersal efficiency or to the poor preservation in the samples. Tubuliflorae (average 25%), Poaceae (average 6.26%), Cerealia and other crop plants (average 7.68%) are other prominent taxa in the pollen rain. The nearly complete absence of members of tropical dry deciduous forests in the pollen spectra likely is due to the fact that most species in this vegetation type are not wind pollinated. 相似文献