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991.
992.
Soil Organic Carbon is Increased in Mixed-Species Plantations of Eucalyptus and Nitrogen-Fixing Acacia 总被引:1,自引:0,他引:1
Soil organic carbon (soil C) sequestration in forests is often higher under nitrogen (N2)-fixing than under non-N2-fixing tree species. Here, we examined whether soil C could be increased using mixed-species plantations compared to monocultures, which are less productive aboveground than mixtures. In addition, we compared soil C sequestration under N2-fixing trees with non-N2-fixing trees that received N fertilizer. Monocultures of Eucalyptus globulus (E) and the N2-fixing Acacia mearnsii (A) and mixtures of these species were planted in a replacement series: 100%E, 75%E + 25%A, 50%E + 50%A, 25%E + 75%A and 100%A. Soil samples were also collected from fertilized monoculture treatments (100%EFer) of E. globulus (250 kg N ha?1). Total organic C, N and phosphorus were determined at age 8 years at two soil depths (0–10 cm and 10–30 cm) and three density fractions of soil organic matter (SOM) were quantified for 0–5 cm depth. Soil C was highest in the 50%E + 50%A mixed stand and was highly correlated with aboveground biomass, not to the percentage of A. mearnsii in mixtures. This was largely due to soil C at 10–30 cm because there were no treatment effects on soil C at 0–10 cm. All density fractions of SOM at 0–5 cm increased with the percentage of A. mearnsii. In E. globulus monocultures, N fertilization did not increase soil C when compared with unfertilized stands. These results indicate that the inclusion of N2-fixing trees into eucalypt plantations may increase soil C stocks through increased productivity. 相似文献
993.
The effect of hydration on Staphylococcus epidermidis , the predominant resident bacterial flora, was studied on skin affected by leprosy and known to have impaired sweating. Normal areas served as control. Significantly higher bacterial counts were observed in affected areas compared with normal-looking skin in 16/19 of the patients. Artificial application of Staph. epidermidis on leprosy-affected and unaffected areas, however, showed equivocal results, as in only 50% of the patients were higher counts obtained in affected compared with unaffected sites. The possible responsible factors for the present observation are discussed. 相似文献
994.
995.
Kathryn D. Sheikh Shefali Khanna Stephen W. Byers Albert J. Fornace Jr. Amrita K. Cheema 《Journal of biomolecular techniques》2011,22(1):1-4
Metabolomics is the comprehensive assessment of endogenous metabolites of a biological system. “Oncometabolomics” is a rapidly emerging field with potential for developing specific biomarkers for early detection, diagnosis, and disease prognosis. Given the power of this technology, the availability of standardized sample preparation methods for immortalized human cancer cell lines is critical toward augmenting research in this direction. Using MCF-7 cells as a model system, we describe an approach for intracellular metabolite extraction from cell cultures for reproducible and comprehensive metabolite extraction. The samples, when injected onto a reverse-phase 50 × 2.1 mm Acquity 1.7-μm C18 column, using an ultra performance liquid chromatography system (UPLC) coupled with electrospray ionization-quadrupole-time-of-flight-mass spectrometry (ESI-Q-TOF-MS) in positive and negative modes, yielded a data matrix with a total of 2600 features. This method, when compared with a water-extraction procedure described earlier, was found to yield significantly higher coverage and detection of molecular features. Finally, we successfully tested the performance of this method for an array of human cancer cell lines used widely in the cancer research field. 相似文献
996.
997.
Antonia Wiegering Renate Dildrop Christine Vesque Hemant Khanna Sylvie Schneider-Maunoury Christoph Gerhardt 《Molecular biology of the cell》2021,32(8):675
A range of severe human diseases called ciliopathies is caused by the dysfunction of primary cilia. Primary cilia are cytoplasmic protrusions consisting of the basal body (BB), the axoneme, and the transition zone (TZ). The BB is a modified mother centriole from which the axoneme, the microtubule-based ciliary scaffold, is formed. At the proximal end of the axoneme, the TZ functions as the ciliary gate governing ciliary protein entry and exit. Since ciliopathies often develop due to mutations in genes encoding proteins that localize to the TZ, the understanding of the mechanisms underlying TZ function is of eminent importance. Here, we show that the ciliopathy protein Rpgrip1l governs ciliary gating by ensuring the proper amount of Cep290 at the vertebrate TZ. Further, we identified the flavonoid eupatilin as a potential agent to tackle ciliopathies caused by mutations in RPGRIP1L as it rescues ciliary gating in the absence of Rpgrip1l. 相似文献
998.
999.
1000.
Journal of Plant Growth Regulation - Flower fragrance appears as a fascinating facet to attract humans and has significant influence on human lives and in plant reproduction via attracting... 相似文献