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Many biomedical products have already been obtained from marine organisms. In order to search more therapeutic drugs against cancer, this study demonstrates the cytotoxicity effects of Cladiella australis, Clavularia viridis and Klyxum simplex extracts on human oral squamous cell carcinoma (SCC4, SCC9 and SCC25) cells using cell adhesion and cell viability assay. The morphological alterations in SCCs cells after treatment with three extracts, such as typical nuclear condensation, nuclear fragmentation and apoptotic bodies of cells were demonstrated by Hoechst stain. Flow cytometry indicated that three extracts sensitized SCC25 cells in the G0/G1 and S-G2/M phases with a concomitant significantly increased sub-G1 fraction, indicating cell death by apoptosis. This apoptosis process was accompanied by activation of caspase-3 expression after SCC25 cells were treated with three extracts. Thereby, it is possible that extracts of C. australis, C. viridis and K. simplex cause apoptosis of SCCs and warrant further research investigating the possible anti-oral cancer compounds in these soft corals.  相似文献   
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Liuchiu Island is an uplifted coral-reef island located off southwestern Taiwan. A total of four soil pedons, labeled as LC-1 and LC-2 from the Holocene terraces and LC-3 and LC-4 from the Pleistocene terraces, were sampled on the island for this work. These soils were siliceous, and were characterized by enrichment of clay and free iron (Fed). According to Soil Taxonomy, pedons LC-3 and LC-4 were classified as Paleudults and pedons LC-1 and LC-2 were Dystrudepts. The soil properties showed progressive changes from pedon LC-1 to pedon LC-4 in morphology, physical and chemical properties, and clay mineralogy. The contents of total Fe and dithionite-citrate-bicarbonate extractable Fe were significantly higher in pedons LC-3 and LC-4 with high weathering degree than in pedons of LC-1 and LC-2 with less weathering degree. Enrichment of kaolinite and gibbsite in pedons LC-3 and LC-4 also suggested high chemical weathering degree of the soils. The estimated soil ages for all studied pedons were consistent with their degrees in pedogenesis, where pedons LC-3 and LC-4 were located at older terraces and pedons LC-1 and LC-2 were located at younger terraces. Namely, it complied with the geologic interpretation of the continuous and simultaneous uplift and tilt of the island over time. Instead of the in situ weathering from the underlying coral reef limestone, all soils developed from siliceous parent materials deposited onto the surfaces. The SiO2/Al2O3 ratios of soils indicated a component of loess may have been incorporated from continental China as part of the parent material, which confirmed a climate change of strong monsoons or severe dust storms occurred before the Holocene. However, soil development increased by the subsequent warm and humid climates of the interglacial stage over time.  相似文献   
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Currently, global warming is worsening, causing the difficulty of cultivating crops in open fields, and leading to unstable quality of crops. Plant factories provide a well-controlled growth environment for precisely cultivating plants. However, uneven temperature distributions (UTDs) still occur at each cultivation shelf in plant factories, which decreases the yields (fresh weight) of plants. In this study, a wireless sensor network (WSN)-based automatic temperature monitoring and fan-circulating system for precision cultivation in plant factories is proposed, and it is built upon the technologies of WSN, ordinary kriging spatial interpolation, and automation control, to precisely find the UTD areas of cultivation shelves. Once a UTD area occurs, the fan-circulating system can be triggered immediately to automatically trace the area and circulate the air. This action can effectively improve the air flow in the cultivation zone, providing optimal growth conditions for plants. The proposed system has been deployed in two plant factories that grew Boston lettuces, and a series of performance evaluation experiments were conducted. The experimental results indicate that the fresh weight of the harvested lettuces increases by 61–109% when employing the proposed system that efficiently and significantly decreases the variation of the temperature in the cultivation zone.  相似文献   
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Purpose

Moso bamboo (Phyllostachys edulis), an important economic crop, is distributed from low- to medium-elevation mountains in Taiwan. Bamboo is a fast-growing herbaceous species with an extensive rhizome structure. With the hypothesis that the characteristics of soil organic matter and microbes might change after long-term bamboo plantation, we investigated different fractions of organic C and N as well as soil microbial biomass and activities in five moso bamboo plantations along an elevation gradient in Central Taiwan.

Materials and methods

Five soil samples (top 10 cm of soil) were collected from each bamboo plantation (600, 800, 1,000, 1,200, and 1,400 m above sea level (asl)) in January 2011. Soil was processed and analyzed for soil total C and N contents, biologically available C, potentially mineralizable N, soil microbial biomass and soil respiration (CO2). Two extraction methods (2 M KCl and hot-water extraction) were used to estimate soil soluble organic C and N (SbOC and SbON) and soil inorganic N (NH4 + and NO3 ?) concentrations to evaluate the relationship with soil organic matter and microbe characteristics in bamboo plantations.

Results and discussion

Soil total C and N contents as well as soil microbial biomass and soil respiration (CO2) of the bamboo plantations increased along the elevation gradient. Temperature changes along elevation contributed to such variations observed among the selected bamboo plantations. The SbON in hot-water extracts was highest in the 1,200-m plantation, then in the 1,400-m plantation, and lowest in the low-elevation plantations (600, 800, and 1,000 m). However, SbON in 2 M KCl extracts did not differ by elevation. The SbON was strongly correlated with soil total N in both 2 M KCl and hot-water extracts, but only SbON in hot-water extracts was strongly correlated with microbial biomass N and potentially mineralizable N. SbOC was strongly correlated with soil total C content, microbial biomass C, and biologically available C in both 2 M KCl and hot-water extracts.

Conclusions

Soil total C and N, SbOC and SbON, and microbial biomass characteristics increased in the moso bamboo plantations with increasing elevation. No altitudinal difference in specific soil respiration (CO2) rate suggested that the enhanced potentially mineralizable N and soil respiration (CO2) in the high-elevation plantations were associated with increased microbial biomass rather than microbial activities.  相似文献   
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We selected sites of natural broad-leaved forests and adjacent coniferous plantations (Cunninghamia konishii and Calocedrus formosana of 30 and 80 years old, respectively) in central Taiwan to evaluate the effects of plantations on soil organic matter (SOM) characteristics and composition. SOM was characterized by chemical analyses, solid-state 13C cross-polarization magic-angle nuclear magnetic resonance (CPMAS 13C NMR), and optical measurements. Semiquantitative analysis of CPMAS 13C NMR spectra showed the litter of broad-leaved forests to be less resistant to decomposition than that of coniferous forests. The humification degree of SOM was higher under broad-leaved than coniferous forests because of the relatively high percentage of aromatic C and carboxyl C in the humic acids (HAs) of A horizons under broad-leaved forests. Additionally, the E 4/E 6 ratio of HAs was lower in the A horizon under broad-leaved than coniferous forests, which reflected more condensation of SOM. High alkyl C content under coniferous forests could be attributed to needle litter quality, which has a high content of waxes or lipids. Afforestation with conifers induced accumulation of the litterfall layer, gradually increased SOM concentrations, and changed the composition structures of SOM in the topsoils.  相似文献   
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As a folk medicine, the hot-water infusion of water caltrop fruits has been used to protect the liver. In this study, the outer skins of mature water caltrop fruits ( Trapa taiwanensis Nakai) were removed, forced-air-dried, pulverized, and subjected to extraction with hot water, and the infusion was lyophilized and pulverized to prepare a hot water extract of T. taiwanensis (HWETT). HWETT was subjected to assays of α,α-diphenyl-β-picrylhydrazyl scavenging activity, reducing power, Trolox equivalent antioxidant capacity, and antioxidative potency, and all determinations showed HWETT to be a potent antioxidant. As further analyzed with LC-MS, two major HPLC-detected components were elucidated as gallic acid and ellagic acid. Hepatoprotective activity of HWETT was assessed with Sprague-Dawley male rats by oral administration. Six groups of rats (n = 8 for each) were respectively treated, namely, control, CCl(4) (20% CCl(4)/olive oil by 2.0 mL/kg bw), CCl(4) and Silymarin (200 mg/kg bw), CCl(4) and low HWETT dose (12.5 mg/kg bw), CCl(4) and medium HWETT dose (25 mg/kg bw), and CCl(4) and high HWETT dose (125 mg/kg bw). After 8 weeks, all animals were fasted for an additional day and sacrificed to collect blood, liver, and kidney for analyses. Histopathological examinations showed that oral administrations with Silymarin and HWETT were effective in protecting the liver from CCl(4)-caused fatty change. Oral administration of HWETT at 125 mg/kg bw was more effective than was Silymarin at 200 mg/kg bw. On biochemical analyses, oral administrations with HWETT at medium and high doses were effective (p < 0.05) in lowering CCl(4)-caused increases of alanine aminotransferase and aspartate aminotransferase activities. It is of merit to demonstrate HWETT as a potent source of antioxidants and hepatoprotective agents.  相似文献   
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In an attempt to elevate temperature to facilitate glycation, a nonenzymatic reaction by incubation of bovine serum albumin (BSA) and fructose at 50 °C for 24 h has been developed. As conducted and compared to a routine procedure by incubation of BSA and fructose at 37 °C for 168 h, the reactant fluorescence intensities and SDS-PAGE-detected glycated BSA quantities produced by both test temperatures increased with time of incubation. As the Amadori products and α-dicarbonyl compounds during incubation were quantified, both quantities produced at each temperature also increased with an increase of time of incubation, and their trends of changes at both temperatures were similar. In practical application for the detection and screening of the antiglycative phytochemicals, each of 20 peanut root extracts was introduced to a series of BSA-fructose solutions and incubated at 37 and 50 °C for 168 and 24 h, correspondingly. All extracts exhibited notable activities and varied depending on peanut origins. Pair comparison of the resultant antiglycative activities determined at 37 and 50 °C showed that both determined activities for each peanut root extract deviated limitedly. As further analyzed, SDS-PAGE-detected glycated BSA quantities formed at 50 °C were closely proportional to the antiglycative activities determined on the basis of their fluorescence intensities. It is of merit to demonstrate that fluorescence-based determination of BSA-fructose reactant after incubation at 50 °C for 24 h is practical and time-saving in the detection and screening of antiglycative phytochemicals.  相似文献   
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