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941.
分析新形势下农业科研单位干部人事档案管理的现状,提出应对措施,强化干部人事档案管理,为单位人力资源开发提供完整的人才信息保障。  相似文献   
942.
云南文山烟区烤烟品种致香物质含量的差异   总被引:1,自引:0,他引:1  
为了解不同烤烟品种香气物质含量的差异,对云南文山烟区3个主栽品种KRK26、K326和云烟87的多酚、有机酸、挥发性香气物质等致香成分含量进行了分析。结果表明,云南文山3个烤烟主栽品种的各类致香物质含量存在显著差异:云烟87烟叶的杂环类化合物含量突出,显著高于K326和KRK26,醛类物质含量最高,酮类和醇类物质以及质体香味成分的二氢猕猴桃内酯、香叶基丙酮和5,6-环氧-β-紫罗兰酮、亚油酸含量最高;K326烟叶的多酚含量最高,显著高于KRK26和云烟87;KRK26的质体香味中的巨豆三烯酮和柠檬酸含量突出,显著高于K326和云烟87,草酸含量最高,丙二酸含量则显著低于K326和云烟87。  相似文献   
943.
花生高油酸育种研究进展   总被引:7,自引:0,他引:7  
花生是我国重要的油料作物、经济作物和出口创汇作物。花生籽粒油脂的品质是由脂肪酸的组成决定的,高油酸的花生油脂稳定性好,有更高的市场价值与营养价值。因此选育高油酸的花生材料和品种已成为目前花生品质改良育种的重要内容。本文综述了高油酸含量性状的遗传规律、高油酸产生的分子机制、杂交育种、突变育种、基因工程育种等方面的研究进展。分析高油酸花生育种中存在的问题,以期为我国花生高油酸育种和种质资源的发掘与利用提供参考。  相似文献   
944.
通过对不同栽培密度与水稻纹枯病的发生、发展之间的关联进行田间试验研究。结果表明,在同是30.0cm×13.2cm插秧规格的条件下,随着穴株数的增加纹枯病发病程度呈递增趋势,4株/穴时病情指数为0.68、6株/穴时病情指数为0.96、8株/穴时病情指数为1.72、10株/穴时病情指数为2.02。  相似文献   
945.
颜士敏 《中国稻米》2014,(3):48-49,53
本文简述了江苏省机插秧的发展现状,分析了水稻机插在江苏省推广应用中存在的问题,并从品种应用、育秧环节、栽插规格、肥水运筹等方面阐述了机插秧的高产栽培技术对策。  相似文献   
946.
A monoacylglycerol (1) and a 1:1 mixture of two monogalactosyl diacylglycerols (MGDGs) (2 and 3) were isolated from the brown seaweed Fucus spiralis Linnaeus. The structures were elucidated by spectroscopic means (NMR and MS) and by comparison with the literature. Compound 1 was composed of a glycerol moiety linked to oleic acid (C18:1 Ω9). Compounds 2 and 3 contained a glycerol moiety linked to a galactose unit and eicosapentaenoic acid (C20:5 Ω3) combined with octadecatetraenoic acid (C18:4 Ω3) or linolenic acid (C18:3 Ω3), respectively. The isolated compounds were tested for their cytotoxic and anti-inflammatory activity in RAW 264.7 macrophage cells. All of them inhibited NO production at non-cytotoxic concentrations. The fraction consisting of compounds 2 and 3, in a ratio of 1:1, was slightly more effective than compound 1 (IC50 of 60.06 and 65.70 µg/mL, respectively). To our knowledge, this is the first report of these compounds from F. spiralis and on their anti-inflammatory capacity.  相似文献   
947.
The mechanism for how fucoxanthin (FX) suppressed adipose accumulation is unclear. We aim to investigate the effects of FX on metabolic rate and expressions of genes related to thermogenesis, mitochondria biogenesis and homeostasis. Using a 2 × 2 factorial design, four groups of mice were respectively fed a high sucrose (50% sucrose) or a high-fat diet (23% butter + 7% soybean oil) supplemented with or without 0.2% FX. FX significantly increased oxygen consumption and carbon dioxide production and reduced white adipose tissue (WAT) mass. The mRNA expressions of peroxisome proliferator-activated receptor (PPAR) γ coactivator-1α (PGC-1α), cell death-inducing DFFA-like effecter a (CIDEA), PPARα, PPARγ, estrogen-related receptor α (ERRα), β3-adrenergic receptor (β3-AR) and deiodinase 2 (Dio2) were significantly upregulated in inguinal WAT (iWAT) and epididymal WAT (eWAT) by FX. Mitochondrial biogenic genes, nuclear respiratory factor 1 (NRF1) and NRF2, were increased in eWAT by FX. Noticeably, FX upregulated genes of mitochondrial fusion, mitofusin 1 (Mfn1), Mfn2 and optic atrophy 1 (OPA1), but not mitochondrial fission, Fission 1, in both iWAT and eWAT. In conclusion, dietary FX enhanced the metabolic rate and lowered adipose mass irrespective of the diet. These were associated with upregulated genes of the PGC-1α network and mitochondrial fusion in eWAT and iWAT.  相似文献   
948.
Tanjungides A (1) (Z isomer) and B (2) (E isomer), two novel dibrominated indole enamides, have been isolated from the tunicate Diazona cf formosa. Their structures were determined by spectroscopic methods including HRMS, and extensive 1D and 2D NMR. The stereochemistry of the cyclised cystine present in both compounds was determined by Marfey’s analysis after chemical degradation and hydrolysis. We also report the first total synthesis of these compounds using methyl 1H-indole-3-carboxylate as starting material and a linear sequence of 11 chemical steps. Tanjungides A and B exhibit significant cytotoxicity against human tumor cell lines.  相似文献   
949.
Surface-associated marine bacteria are an interesting source of new secondary metabolites. The aim of this study was the isolation and identification of epiphytic bacteria from the marine brown alga, Bifurcaria bifurcata, and the evaluation of the antioxidant and antimicrobial activity of bacteria extracts. The identification of epiphytic bacteria was determined by 16S rRNA gene sequencing. Bacteria extracts were obtained with methanol and dichloromethane (1:1) extraction. The antioxidant activity of extracts was performed by quantification of total phenolic content (TPC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and oxygen radical absorbance capacity (ORAC). Antimicrobial activities were evaluated against Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Salmonella enteritidis, Staphylococcus aureus, Saccharomyces cerevisiae and Candida albicans. A total of 39 Bifurcaria bifurcata-associated bacteria were isolated and 33 were identified as Vibrio sp. (48.72%), Alteromonas sp. (12.82%), Shewanella sp. (12.26%), Serratia sp. (2.56%), Citricoccus sp. (2.56%), Cellulophaga sp. (2.56%), Ruegeria sp. (2.56%) and Staphylococcus sp. (2.56%). Six (15.38%) of the 39 bacteria Bifurcaria bifurcata-associated bacteria presented less than a 90% Basic Local Alignment Search Tool (BLAST) match, and some of those could be new. The highest antioxidant activity and antimicrobial activity (against B. subtilis) was exhibited by strain 16 (Shewanella sp.). Several strains also presented high antimicrobial activity against S. aureus, mainly belonging to Alteromonas sp. and Vibrio sp. There were no positive results against fungi and Gram-negative bacteria. Bifurcaria bifurcata epiphytic bacteria were revealed to be excellent sources of natural antioxidant and antimicrobial compounds.  相似文献   
950.
Two new guaiazulene-based analogues, ochracenoids A (1) and B (2), along with four known analogues (3–6), were isolated from the gorgonian Anthogorgia ochracea collected from the South China Sea. The planar structures of the new compounds were elucidated by comprehensive spectroscopic data. The absolute configuration of 1 was determined as 3R by the comparison of TDDFT calculated electronic circular dichroism with its experimental spectrum. Compound 1 is a rare guaiazulene-based analogue possessing a unique C16 skeleton. The possible generation process of 1 through an intermolecular one-carbon-transfer reaction was also discussed. Compound 2 was previously described as a presumed intermediate involved in the biogenesis of anthogorgienes A and I. Compound 3 exhibited antiproliferative effects on the embryo development of zebrafish Danio rerio.  相似文献   
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