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41.
‘伦晚脐橙’成熟果实及其留树保鲜果实的香气成分分析   总被引:1,自引:0,他引:1  
采用顶空固相微萃取-气质联用技术测定了‘伦晚脐橙’成熟果实和留树保鲜果实的香气成分,结果表明,成熟采收(3月30日)后的果实中香气物质有28种,占挥发性物质总量的97.69%,主要成分为烃类、醛类、醇类、酯类和酮类化合物;而留在树上保鲜(5月7日)的果实中香气成分仅检测到15种,占挥发性物质总量的87.11%,特征香气成分D-柠檬烯和β-月桂烯明显减少,且未检测到醇类和酮类化合物,但巴伦西亚桔烯的相对含量剧增,相对含量高达20.27%,成为主要香气物质之一。  相似文献   
42.
叶?在我国原记载2种,作者查看了采自江南7省区的标本30多件。共鉴定为8种,加上原有纪录的一未见种,我国总计9种,其中包括5新种和2种我国新纪录,本文主要记述4新种,属于丽叶?亚属的一新种已另文发表;并编制了我国产叶?的种检索表。 叶?多分布在雨量充沛地区,特别是热带岛屿,而本文中的泛叶?却采自远离海岸1200多km的贵州北部,以及藏叶?乃发现于北纬 29.2°的西藏墨脱,这对世界有关分类区系的研究,提供了新的资料。  相似文献   
43.
Camouflage is one of the most widespread and powerful strategies that animals use to make detection/recognition more difficult. Many orb-web spiders of the genus Cyclosa add prey remains, plant debris, moults, and/or eggsacs to their webs called web decorations. Web decorations resembling spider body colour pattern have been considered to camouflage the spider from predators. While this camouflage is obvious from a human's perspective, it has rarely been investigated from a predator's perspective. In this s...  相似文献   
44.
陕西关中小麦品种更替中性状演变及其发展方向   总被引:9,自引:1,他引:9  
以关中地区四十年代到九十年代推广种植的主要代表品种及品系为材料,对其分蘖动态、生育期、株高因素、穗部性状、产量、生物学产量、经济系数及冬春性等20个性状进行了研究,其结果表明关中地区四十代到九十年代小麦品种性状演变的趋势是:冬、春季分蘖变化不大,冬季分蘖趋向略增;春季分蘖趋向略减;成穗数趋向降低,拨节,抽穗和开花期有趋早倾向,而成熟期和总生育天数无明显变化,株高降低极明显(137.7-85.2cm  相似文献   
45.
对曲江县养牛业所取得的经济效益、生态效益和社会效益作了初步的分析和讨论.  相似文献   
46.
陈建  李枢强 《蛛形学报》1995,4(2):137-139
记述采自我国云南省勐腊的盖蛛属1新纪录种-鹤嘴盖蛛Nerienemacella(Thorell.1898)。  相似文献   
47.
Non-high-density lipoprotein cholesterol(NHDL) is an independent and superior predictor of CVD risk as compared to low-density lipoprotein alone. It represents a spectrum of atherogenic lipid fractions with possibly a distinct genomic signature. We performed genome-wide association studies (GWAS) to identify loci influencing baseline NHDL and its postprandial lipemic (PPL) response. We carried out GWAS in 4,241 participants of European descent. Our discovery cohort included 928 subjects from the Genetics of Lipid-Lowering Drugs and Diet Network Study. Our replication cohorts included 3,313 subjects from the Heredity and Phenotype Intervention Heart Study and Family Heart Study. A linear mixed model using the kinship matrix was used for association tests. The best association signal was found in a tri-genic region at RHOQ-PIGF-CRIPT for baseline NHDL (lead SNP rs6544903, discovery p = 7e?7, MAF = 2 %; validation p = 6e?4 at 0.1 kb upstream neighboring SNP rs3768725, and 5e?4 at 0.7 kb downstream neighboring SNP rs6733143, MAF = 10 %). The lead and neighboring SNPs were not perfect surrogate proxies to each other (D′ = 1, r 2 = 0.003) but they seemed to be partially dependent (likelihood ration test p = 0.04). Other suggestive loci (discovery p < 1e?6) included LOC100419812 and LOC100288337 for baseline NHDL, and LOC100420502 and CDH13 for NHDL PPL response that were not replicated (p > 0.01). The current and first GWAS of NHDL yielded an interesting common variant in RHOQ-PIGF-CRIPT influencing baseline NHDL levels. Another common variant in CDH13 for NHDL response to dietary high-fat intake challenge was also suggested. Further validations for both loci from large independent studies, especially interventional studies, are warranted.  相似文献   
48.
We used a random coefficient regression (RCR) model to estimate growth parameters for the time series of observed serum glucose levels in the Replicate 1 of the Genetic Analysis Workshop 13 simulated data. For comparison, a two time-point interval was also selected and the slope between these two observations was calculated. This process yielded four phenotypes: the RCR growth phenotype, a two time-point slope phenotype, and Time 1 and Time 2 serum glucose level phenotypes. These four phenotypes were used for linkage analyses on simulated chromosomes 5, 7, 9, and 21, those chromosomes that contained loci affecting the growth course for serum glucose levels. The linkage analysis of the RCR-derived phenotype showed overwhelming evidence for linkage at one locus (LOD 65.78 on chromosome 5), while showing elevated but nonsignificant LOD scores for two other loci (LOD 1.25 on chromosome 7, LOD 1.10 on chromosome 9), and no evidence of linkage for the final locus. The two time-point slope phenotype showed evidence for linkage at one locus (LOD 4.16 on chromosome 5) but no evidence for linkage at any of the other loci. A parallel cross-sectional approach, using as input phenotypes the endpoints of the two-point slope phenotype, gave strong linkage results for the major locus on chromosome 5 (maximal LOD scores of 17.90 and 27.24 for Time 1 and Time 2, respectively) while showing elevated but nonsignificant linkage results on chromosome 7 (maximal LOD scores of 1.71 and 1.48) and no evidence for linkage at the two remaining loci. The RCR growth parameter showed more power to detect linkage to the major locus than either the cross-sectional or two-point slope approach, but the cross-sectional approach gave a higher maximal LOD score for one of the minor loci.  相似文献   
49.
我国伊蚊—新亚属及—新种(双翅目:蚊科)   总被引:1,自引:0,他引:1  
1985年6月,在进行滇西类业区系调查中采获一批伊蚊,经鉴定,发现1新亚属,现将该亚属及1新种描述如下。华蚊亚属Sinoaedes,新亚属 亚属特征:雌蚊 中型,暗黑色,具银白鳞饰。触须暗色。喙暗色。前胸前背片平覆宽白鳞。中胸盾片平覆褐色窄鳞;小盾片三叶状,具宽鳞;后背片光裸。有气门后鬃;有1根中胸下后鬃。翅鳞暗色。各足除股节腹面具白色区外,一致暗色。腹节暗色。第  相似文献   
50.
作者采用水媒法和溶媒法,分别将茯苓聚糖直接羧甲基化,得到了具有抗肿瘤活性的羧甲基茯苓聚糖,并对产物进行了IR、~(13)CNMR分析。  相似文献   
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