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1.
白三叶草花蜜腺突起环状,位于花丝基部并延续至花托上,属于环状花托/雄蕊蜜腺,蜜腺由分泌表皮和产蜜组织组成.在花的发育过程中,蜜腺由本身的原始细胞分裂,分化而来.分泌表皮具角质层,其上分布有变态气孔器,蜜汁经产蜜组织合成后,经变态气孔器泌出.  相似文献   
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多花蔷薇(Rose multiflora. cathayensis)又名红刺玫、刺花,系多年生落叶灌木,野生于甘肃省陇南山区,生长在海拔500~1900 m的山峰、河岸或山坡缘及灌木丛林中,花的资源丰富,是甘肃省目前需开发的野生芳香植物之一,多花蔷薇花为粉红色,花期为5月中旬至5月底,花中含芳香油,可用作化妆、皂用香精等,有关多花蔷薇花的化学成分,未见文献报道,我们将多花蔷薇花的石油醚浸膏用乙醇在0℃脱蜡3次得净油,再经硅胶柱层析分离得纯  相似文献   
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Modern functionally oriented surgery of the larynx increasingly requires exact knowledge of the anatomy and landmarks of the endolaryngeal structures in relation to the laryngeal skeleton. Review of the literature reveals several opposing statements and controversial anatomical definitions regarding several clinically critical points. In order to obtain basic anatomical data morphological measurements were performed on a total of 50 laryngeal specimens. Measurements were taken on whole organs and on cuts in the horizontal and in the frontal plane, as well. The data were evaluated statistically, which resulted in the determination of average configurations and dimensions of cartilages and soft tissues of the larynx. In particular, the projection of the deeper structures on the surface and the distances and angles between the different structures were taken into consideration. In order to make these data clinically applicable a scale model has been developed that will allow a direct correlation and application for individual surgery.  相似文献   
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《Analytica chimica acta》2004,515(1):117-125
In this work a supervised chemometric approach to the discrimination of Italian honey samples from different floral origin is presented. The analytical data of 73 Italian honey samples from six varieties (chestnut, eucalyptus, heather, sulla, honeydew, and wildflower) have been processed by Linear Discriminant Analysis (LDA), using two different variable selection procedures (Fisher F-based and stepwise LDA). Three and two variables, respectively have been necessary to obtain a 100% predictive ability as evaluated by cross-validation. Successively, a class modeling approach has been followed, using UNEQ. The resulting models showed 100% sensitivity and specificity.  相似文献   
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HPLC-MS–MS analysis of unifloral honey extracts has shown the occurrence of flavonoid glycosides in most of the analyzed samples. These compounds are not present in large amounts, but can reach up to 600 μg/100 g honey in canola and rapeseed honeys. Rhamnosyl-hexosides (tentatively rutinosides and neohesperidosides) and dihexosides (hexosyl(1→2)hexosides and hexosyl(1→6)hexosides) of flavonols such as quercetin, kaempferol, isorhamnetin and 8-methoxykaempferol, are the main flavonoid glycosides found in honey. However, flavonoid triglycosides and monoglycosides are also detected in some floral origins. Eucalyptus and orange blossom nectars were collected and analyzed showing that nectar flavonoid glucosides, as is the case of eucalyptus flavonoids, can be readily hydrolyzed by the bee saliva enzymes, while flavonoid rhamnosyl-glucosides, as is the case of citrus nectar flavonoids, are not hydrolyzed, and because of these reasons the flavonoid glycoside content of citrus honey is higher than that of eucalyptus honey that contains mainly aglycones. The flavonoid glycoside profiles detected in honeys suggest that this could be related to their floral origin and the results show that the HPLC-MSn ion trap analysis of flavonoid glycosides in honey is a promising analytical method to help in the objective determination of the floral origin of unifloral honeys.  相似文献   
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Summary The structural differences between bitter almond odour substances and molecules with cinnamic or floral odour notes were investigated by comparison of a number of compounds with various synthetic modifications. An attempt was made to find a systematic principle for the change of the odour notes.Dedicated to Prof. Dr. K. Schlögl on the occasion of his 70th anniversary  相似文献   
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通过对不同花期杏、苹果花内蜜腺的糖含量和酶活性的研究,结果表明两种蜜腺可溶性糖的主要成分是葡萄糖,其外输出量均在盛花期达到最大;不同花期两种蜜腺蔗糖酶、α,β-淀粉酶和过氧化物同功酶活性的变化具有一定规律性,并讨论了两种蜜腺糖含量和酶活性的相对差异及其相关性。  相似文献   
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α-Ketol of octadecadienoic acid (KODA, 1) has been suggested to play a role in the photoperiod-regulated flowering in Pharbitis nil. The level of 1 in cotyledons is temporarily controlled during short-day conditions. The biosynthesis of 1 is well studied in plants; however, its in vivo conversion is less understood. We have investigated this issue by studying the metabolism of exogenously-applied [U-13C]-1, [1-14C]-1, and non-labeled 1 in P. nil seedlings by the spectroscopic methods and identified six major metabolites (4-9). We have also found that the enantiomers of 1 are differentially metabolized in P. nil seedlings.  相似文献   
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