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81.
为探寻安全高效的可食性涂膜应用于沃柑保鲜,以羧甲基壳聚糖(Carboxymethyl chitosan,CMCS)和香茅草精油(XMC)两种天然材料为原料制备复合涂膜材料,并检验复合涂膜材料的理化性质,后以蒸馏水为对照,研究0.5%香茅草精油与1.0%羧甲基壳聚糖复合涂膜处理(0.5% XMC-1.0% CMCS)对沃柑果实青霉、绿霉病害的防控效果及其对果实抗病防御酶活性和果实品质的影响。结果表明,香茅草精油的添加提高了膜的韧性、完整性、粗糙度、不透明度,降低了水蒸气透过率。同时,0.5%香茅草精油与1.0%羧甲基壳聚糖复合处理显著(P<0.05)抑制了沃柑果实青霉、绿霉病的发病率及病斑直径的扩展。此外,与对照组相比,0.5%香茅草精油与1.0%羧甲基壳聚糖复合涂膜处理诱导提高了沃柑果皮中苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)、多酚氧化酶(PPO)、几丁质酶(CHI)活性及苯酚、类黄酮、花青素等抗性物质的含量,且在整个贮藏过程中保持了果实品质。综上,香茅草精油的加入提高了复合膜的整体性能,0.5% XMC-1.0% CMCS复合涂膜处理诱导提高了采后沃柑果实的抗病防御酶活性和抗性物质含量,增强沃柑果实抗青绿霉病的能力,维持了果实贮藏品质。  相似文献   
82.
The roles of secreted frizzled-related protein 2 (sFRP2) in organ development of vertebrate animals are not well understood. We investigated expression of sFRP2 during embryogenesis of Arbor Acre broiler chicken eggs. Expression of sFRP2 was detected in the folds and lateral layer of developing brains. The sFRP2 signals in the developing eye were marked as a circle along the orbit. In younger embryos on days 3-6, the sFRP2 signals were consistent with growth of the sclerotome, suggesting that sFRP2 may be associated with somite development. Furthermore, with the exception of bones, sFRP2 mRNA was detectable in the interdigital tissue of embryos older than eight days as the limbs matured. This revealed that sFRP2 might play a role in myogenesis. In situ hybridization was also used to analyze the expression of sFRP2 in day 3-10 chick embryos. Signals were expressed in the gray matter of the developing brain coelom, including the optic lobe, metencephalon, myelencephalon, mesencephalon and diencephalon. The developing eyes contained an intercellular distribution of sFRP2 in the pigmented layer of the retina and photoreceptors. Furthermore, sFRP2 was expressed in the mantle layer of the neural tube and notochord. Based on these findings, it seems reasonable to suggest that sFRP2 may play an active role in embryogenesis, especially in development of the neural system, eyes, muscles and limbs.  相似文献   
83.
品牌形象一直企业最关心的问题,但是品牌危机问题日趋普遍。文章试图以乳制品行业为例,浅析品牌危机的管理机制。  相似文献   
84.
Environmental innovation is the fundamental support for sustainable development. Exploiting Chinese provincial panel data from 2007 to 2017, this study investigates the impacts of fiscal decentralization on environmental innovation. In particular, we discuss the regulating role of government’s environmental protection expenditures relying on the mediator effect model. The empirical analyses show that fiscal decentralization cannot only directly promote environmental innovation, but also indirectly weaken environmental innovation through the environmental protection expenditure of the local government. The overall performance is that fiscal decentralization promotes environmental innovation. It is noteworthy that there is regional heterogeneity in the impact of fiscal decentralization on environmental innovation. The impact in the east is significantly higher than in the central and western regions in China.  相似文献   
85.
为了研究不同植被类型对沙区土壤的改良效果,调查沙区土壤的养分状况,笔者对青龙湾沙区不同植被类型的土壤有机质、有效氮、速效钾、有效磷等指标进行分析。结果表明,青龙湾沙区土壤pH值范围为7.40~7.72,土壤呈中性略偏微碱性;土壤有机质、有效氮、有效磷及速效钾含量偏低。有机质含量对于土壤其他营养元素的含量和有效性均具有比较大的影响。不同植被类型对沙区土壤的改良具有一定的差异,除农田外,果园、毛白杨刺槐混交林的改良效果较好,小叶杨林改良效果较差。总体来说,经过生态林改良后的土壤养分状态得到明显改善。  相似文献   
86.
Bruchid, Callosobruchus spp. (Coleoptera: Bruchidae), is a serious pest during storage of seeds of mungbean (Vigna radiata (L.) Wilczek) and other Vigna species. A source of resistance to this pest has been identified in Vigna sublobata (Roxb.) Bairig. accession TC1966. Two hundred recombinant inbred lines at the F12 generation have been developed for molecular mapping of bruchid resistance (Br) gene in TC1966. Through bulked segregant analysis (BSA), ten randomly amplified polymorphic DNA (RAPD) markers associated with the bruchid resistance gene were successfully identified. A total of four closely linked RAPDs were cloned and transformed into sequence characterized amplified region (SCAR) and cleaved amplified polymorphism (CAP) markers. Seven CAPs developed from the identified RAPD markers showed tighter linkage with the Br gene than the original RAPD. Through transformation of RAPDs into CAPs, codominant markers for bruchid resistance were successfully obtained. Homozygous genotypes of these PCR-based markers were estimated to contribute 85% of the variance for seed damage when the insect assay was performed under favorable growth conditions for bruchid.  相似文献   
87.
水稻不同群体结构的丰产特性的研究   总被引:3,自引:0,他引:3  
本文根据1961—1962二年试验结果,对三种不同类型的水群体结构,即“少苗促进分蘖”、“中苗促进分蘖”、“多苗控制分蘖”在不同施肥水平下的丰产特性,进行了分析和讨论,结果指出:在施肥量较少时,以“多苗控制分蘖”的群体产量较高;在施肥量较多时,以“少苗促进分蘖”的群体产量较高。本文还从每亩穗数与每穗粒数的关系、叶面积动态以及干物质的积累和分配等方面,进一步分析了上述三种群体结构产量形成过程的特点。关于分蘖的多少对水稻群体发育的影响,也进行了初步的探讨。  相似文献   
88.
Six new compounds, trans-3-isobutyl-4-[4-(3-methyl-2-butenyloxy)phenyl]pyrrolidine-2,5-dione (1), trans-1-hydroxy-3-(4-hydroxyphenyl)-4-isobutylpyrrolidine-2,5-dione (2), cis-3-(4-hydroxyphenyl)-4-isobutyldihydrofuran-2,5-dione (3), 3-(4-hydroxyphenyl)-4-isobutyl-1H-pyrrole-2,5-dione (4), 3-(4-hydroxyphenyl)-4-isobutylfuran-2,5-dione (5), and dimethyl 2-(4-hydroxyphenyl)-3-isobutylmaleate (6), together with one known compound, 3-isobutyl-4-[4-(3-methyl-2-butenyloxy)phenyl]furan-2,5-dione (7), were isolated from the fruiting bodies of Antrodia camphorata. The structures of the compounds were elucidated by analysis of their spectroscopic data. To investigate the immunomodulatory potential of the compounds, RAW264.7 macrophage cells were treated with the compounds. Compound 1 significantly increased spontaneous TNF-alpha secretion from unstimulated RAW264.7 cells but suppressed IL-6 production [50% inhibition concentration value (IC50) = 10 microg/mL] in LPS-stimulated cells. Compounds 3, 4, and 6 also suppressed IL-6 production with IC50 values of 17, 18, and 25 microg/mL, respectively, suggesting that these four compounds may have an anti-inflammatory effect on macrophage-mediated responses. Of the six compounds, compound 1 was the most effective, exerting both immunostimulatory and anti-inflammatory effects.  相似文献   
89.
This presentation describes amino acid analysis with the gas chromatographic method and experimental conditions using the N-trifluoroacetyl n-butyl ester derivatives; the study we describe here was undertaken to compare gas chromatographic (GC) and ion-exchange chromatographic (IEC) analyses of amino acids in hydrolysates of 9 diverse sample types to gain insight into effects of these 2 chromatographic methods of analysis on variation in amino acid results. Our study showed that values for samples prepared by 2 separate laboratories using the same procedure were generally in good agreement when all of the hydrolysates were analyzed by a single laboratory using a single method of analysis. To compare results from gas chromatography with those from ion-exchange chromatography analyses were performed by 2 different laboratories on the same hydrolysates and on different hydrolysates prepared by the same method by both laboratories. The data demonstrate that GC and IEC can be expected to yield essentially identical results when applied to the same hydrolysate. Agreement is so close that interlaboratory differences in hydrolysate preparation of the same sample contribute as much to variation in amino acid results as does the method of analysis, a fact which should be noted in planning collaborative studies.  相似文献   
90.
Artificial oil bodies (AOBs) are oil droplets that result from self-assembly of a mixture containing triacylglycerols, phospholipids, and membrane proteins of plant seeds. Owing to their small size, stability, hydrophobic core, biocompatibility, and biodegradability, AOBs were explored to examine their feasibility as a drug delivery carrier. This was approached by fusion sesame oleosin (Ole), the primary membrane protein of seed oil bodies, with a small domain consisting of the arginine-glycine-aspartic acid (RGD) motif. The resulting Ole-RGD fusion protein was overproduced in Escherichia coli and then isolated for reconstitution of AOBs. At the optimal condition, the size of stable AOBs was within the range of 100-400 nm. Furthermore, AOBs entrapped with a hydrophobic fluorescence dye were incubated with human tumor cells. As visualized by fluorescent microscopy and confocal microscopy, the RGD-tagged AOBs were able to selectively target cells expressing the αvβ3 integrin. Moreover, these AOBs were effectively internalized and the fluorescence dye that they carried was subsequently released inside the cells. The percentage of cells internalized by AOBs could reach 80% as analyzed by flow cytometry. Taken together, it illustrates a great promise of this proposed approach for targeted delivery of cargo entities to tumor cells.  相似文献   
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