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21.
Kamara BI Brandt EV Ferreira D Joubert E 《Journal of agricultural and food chemistry》2003,51(13):3874-3879
The fermented leaves and stems of Cyclopia intermedia are used to brew Honeybush tea, a herbal tea indigenous to South Africa. The plant is also used to manufacture a sweet herbal infusion used for restorative properties such as soothing coughs and alleviating bronchial complaints including tuberculosis, pneumonia, and catarrh. It is claimed to have a low tannin content and no caffeine and contains various antioxidants. Continued investigations into the phenolic content of the leaves and stems of C. intermedia yielded tyrosol and a methoxy analogue, 2-[4-[O-alpha-apiofuranosyl-(1' '-->6')-beta-d-glucopyranosyloxy]phenyl]ethanol, 4-[O-alpha-apiofuranosyl-(1' '-->2')-beta-d-glucopyranosyloxy]benzaldehyde, five glycosylated flavonols, two isoflavones, four flavanones, two isoflavones, and two flavones. Structure elucidation was done by NMR, CD, and MS methods. Because flavonoids are presumed to contribute significantly toward the scavenging effects of active oxygen species, our results indicate that the tentative claimed health-promoting properties may be attributed to the presence of these and other phenolics in C. intermedia. 相似文献
22.
Grégoire Vincent Jean-François Molino Lucile Marescot Karim Barkaoui Daniel Sabatier Vincent Freycon Jean Baptiste Roelens 《Annals of Forest Science》2011,68(2):357-370
• Introduction
Various processes contribute to shaping the local assemblage of species in hyperdiverse tropical forest. The relative contribution of environmental factors and dispersal limitation in determining the spatial distribution of saplings at local scale is unclear. 相似文献23.
Determination of the conjugated linoleic acids in cow's milk fat by Fourier transform Raman spectroscopy 总被引:1,自引:0,他引:1
Meurens M Baeten V Yan SH Mignolet E Larondelle Y 《Journal of agricultural and food chemistry》2005,53(15):5831-5835
The collective term "conjugated linoleic acid" or "CLA" generally refers to a mixture of conjugated positional and geometric isomers of linoleic (cis-9,cis-12-octodecadienoic) acid. In nature, these isomers are mainly formed in the rumen by biohydrogenation of polyunsaturated fatty acids. This study concerns a first trial of CLA determination in cow's milk fat by Raman spectroscopy. The spectra of pure cis-9-oleic, cis-9,cis-12-linoleic, cis-9,trans-11-linoleic, and trans-10,cis-12-linoleic acids have been examined in comparison with the spectra of selected milk-fat samples containing between 0 and 3% of CLA. The trial of CLA determination by Raman spectroscopy on cow milk fat has reached its objective with the two following results. First, the examination of the Raman spectra allows to identify three specific Raman signals of the chemical bonds associated to the cis,trans conjugated C=C in the rumenic and trans-10,cis-12-octodecadienoic acids at 1652, 1438, and 3006 cm(-1). Second, the calibration of Raman spectrometer for the CLA determination has indicated that these three specific signals suit very well for the accurate and reliable measurement of CLA concentration in milk fat. To our knowledge, the present study is the first successful attempt to determine the CLA content of milk fat by a spectrophotometric method. 相似文献
24.
Srinivasan Samineni Pooran M. Gaur Timothy D. Colmer L. Krishnamurthy Vincent Vadez Kadambot H. M. Siddique 《Euphytica》2011,182(1):73-86
Chickpea (Cicer arietinum L.) is known to be salt-sensitive and in many regions of the world its yields are restricted by salinity. Recent identification
of large variation in chickpea yield under salinity, if genetically controlled, offers an opportunity to develop cultivars
with improved salt tolerance. Two chickpea land races, ICC 6263 (salt sensitive) and ICC 1431 (salt tolerant), were inter-crossed
to study gene action involved in different agronomic traits under saline and control conditions. The generation mean analysis
in six populations, viz. P1, P2, F1, F2, BC1P1 and BC1P2, revealed significant gene interactions for days to flowering, days to maturity, and stem Na and K concentrations in control
and saline treatments, as well as for 100-seed weight under salinity. Seed yield, pods per plant, seeds per plant, and stem
Cl concentration were controlled by additive effects under saline conditions. Broad-sense heritability values (>0.5) for most
traits were generally higher in saline than in control conditions, whereas the narrow-sense heritability values for yield
traits, and stem Na and K concentrations, were lower in saline than control conditions. The influence of the sensitive parent
was higher on the expression of different traits; the additive and dominant genes acted in opposite directions which led to
lower heritability estimates in early generations. These results indicate that selection for yield under salinity would be
more effective in later filial generations after gene fixation. 相似文献
25.
Two beams of light can be quantum mechanically entangled through correlations of their phase and intensity fluctuations. For a pair of spatially extended image-carrying light fields, the concept of entanglement can be applied not only to the entire images but also to their smaller details. We used a spatially multimode amplifier based on four-wave mixing in a hot vapor to produce twin images that exhibit localized entanglement. The images can be bright fields that display position-dependent quantum noise reduction in their intensity difference or vacuum twin beams that are strongly entangled when projected onto a large range of different spatial modes. The high degree of spatial entanglement demonstrates that the system is an ideal source for parallel continuous-variable quantum information protocols. 相似文献
26.
Variations of the Globorotalia menardii complex in cores from the Indian Ocean can be interpreted as indicating climatic changes that are opposite to trends exhibited by the total planktonic fauna. The questionable value of correlations between different water masses based on a single species can be shown by Neogloboquadrina dutertrei subcretacea in cores obtained off the coast of California and Baja California. This information, in addition to previous correlations between Quaternary cores of the Atlantic and Pacific oceans, indicates that the Pleistocene history of the two oceans was parallel. 相似文献
27.
Vincent GE 《Science (New York, N.Y.)》1911,33(861):977-984
28.
Kochendoerfer GG Chen SY Mao F Cressman S Traviglia S Shao H Hunter CL Low DW Cagle EN Carnevali M Gueriguian V Keogh PJ Porter H Stratton SM Wiedeke MC Wilken J Tang J Levy JJ Miranda LP Crnogorac MM Kalbag S Botti P Schindler-Horvat J Savatski L Adamson JW Kung A Kent SB Bradburne JA 《Science (New York, N.Y.)》2003,299(5608):884-887
We report the design and total chemical synthesis of "synthetic erythropoiesis protein" (SEP), a 51-kilodalton protein-polymer construct consisting of a 166-amino-acid polypeptide chain and two covalently attached, branched, and monodisperse polymer moieties that are negatively charged. The ability to control the chemistry allowed us to synthesize a macromolecule of precisely defined covalent structure. SEP was homogeneous as shown by high-resolution analytical techniques, with a mass of 50,825 +/-10 daltons by electrospray mass spectrometry, and with a pI of 5.0. In cell and animal assays for erythropoiesis, SEP displayed potent biological activity and had significantly prolonged duration of action in vivo. These chemical methods are a powerful tool in the rational design of protein constructs with potential therapeutic applications. 相似文献
29.
Vincent WF 《Science (New York, N.Y.)》1999,286(5447):2094-2095
30.
Roy D Liston DR Idone VJ Di A Nelson DJ Pujol C Bliska JB Chakrabarti S Andrews NW 《Science (New York, N.Y.)》2004,304(5676):1515-1518
Strategies for inhibiting phagolysosome fusion are essential for the intracellular survival and replication of many pathogens. We found that the lysosomal synaptotagmin Syt VII is required for a mechanism that promotes phagolysosomal fusion and limits the intracellular growth of pathogenic bacteria. Syt VII was required for a form of Ca2+-dependent phagolysosome fusion that is analogous to Ca2+-regulated exocytosis of lysosomes, which can be triggered by membrane injury. Bacterial type III secretion systems, which permeabilize membranes and cause Ca2+ influx in mammalian cells, promote lysosomal exocytosis and inhibit intracellular survival in Syt VII +/+ but not -/- cells. Thus, the lysosomal repair response can also protect cells against pathogens that trigger membrane permeabilization. 相似文献