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101.
A new dimeric gallic acid glycoside named Humarain (1) was isolated from stem bark of Punica granatum. The structure of the compound was determined by spectroscopic data including 1D and 2D NMR spectral analysis.  相似文献   
102.
In order to develop the resources of native turfgrass,the morphological traits and drought resistance of native Siberian bluegrass (Poa sibirica,abbreviated as PS) was evaluated using the introduced Kentucky bluegrass 'Midnight' (Poa pratensis,abbreviated as PP) as a control.Two water schemes were imposed to plants in this pot culture study in greenhouse.One was with drought stress persistent limiting water supply for 20 days,the other was re-hydrated until 14 days after drought.The leaf shape,turf color,water status and cell plasma membrane permeability were evaluated.Similar changing trends with these parameters were shown for both species,and there were not significant differences with most evaluations during drought and re-water periods.The values leaf width and length of PS were higher while leaf color intensity was slightly lower than that of PP,but the greenness of PS leaf was still visually acceptable.There were not significant differences with cell membrane stability between the two species.In comparison,the native wild species PS possessed the potential for to be domesticated into a new cultivar for turf industry.  相似文献   
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为研究孟加拉干旱区灌溉方式、株距及其交互作用对甘蔗分蘖数量、可榨甘蔗数量、甘蔗产量以及蔗糖含量的影响 ,在孟加拉第 11农业生态区的洪积平原上进行了为期 3年的栽培试验 .试验株距分别为 30 ,4 5,6 0和 75cm ,试验灌溉方式为天然降雨配合点灌和漫灌 .试验区按裂区试验法进行布置 ,灌溉方式则按小区布设 ,株距试验布置在主试验区 .试验结果表明 ,灌溉方式、栽植株距以及它们之间的交互作用对甘蔗产量、含糖量有显著影响 .就株距而言 ,4 5cm的株距可以获得最高的甘蔗产量(75 81t·hm- 2 ) .同样 ,在雨养、点灌及漫灌三种灌溉方式中 ,漫灌的甘蔗产量最高 (91 2 7t·hm- 2 ) .最好的栽培技术组合为 4 5cm株距配合漫灌 ,甘蔗分蘖数、可榨甘蔗数、甘蔗产量、产糖量以及投入产出比分别高达 2 0 3× 10 3株·hm- 2 ,115 53× 10 3株·hm- 2 ,10 1 6 4t·hm- 2 ,8 45t·hm- 2 和 5 52∶1  相似文献   
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Tantry MA  Dar JA  Idris A  Akbar S  Shawl AS 《Fitoterapia》2012,83(4):665-670
Herba Epimedii is a well-known Botanical preparation used over long time in traditional Chinese medicine. The extracts and chemical constituents from Epimedium species are aphrodisiac as well as to treat many ailments. Chemical investigation of lonely species growing in Kashmir Himalaya Epimedium elatum was undertaken to evaluate its chemical profile. Two unusual substituted acylated flavonol glycosides named Elatoside A (1) and Elatoside B (2) have been isolated from the ethanolic extract of E. elatum along with 23 previously known ones (3-25). All isolates were evaluated for antimicrobial and PPAR-γ ligand binding activity, and some of them appeared to be modestly active.  相似文献   
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The present study aimed at analysing the effect of Khat plant extract on rat testicular development. Thirty-two weaned male albino rats (4 weeks old) were divided into four groups consisting of eight animals each. While control animals received normal saline, rats of groups I, II and III received 100, 200 and 300 mg Khat extract per kg body weight dissolved in distilled water by oral gavage daily for 8 weeks, respectively. Blood samples were collected in separate heparinized tubes by cardiac puncture from each rat and processed for measuring plasma levels of reproductive hormones LH, FSH, testosterone and prolactin. Five-µm sections were stained with haematoxylin and eosin and examined by light microscope. Some sections were immunostained for protamine-1 representing a biomarker for intact sperm differentiation. The present study clearly demonstrated that Khat extract has a pronounced effect on testicular maturation of developing albino rats at both the morphological and functional levels. Khat-treated groups revealed a significantly low serum testosterone level and severe impairment of spermatogenesis when compared with control animals. The current findings also verified, for the first time, that the final stages of sperm maturation (spermiogenesis) were strongly impaired after administration of Khat extract to experimental rats particularly at a higher dose (300 mg/kg body weight). This was proved by the very weak, if any, expression of protamine-1 in the maturing spermatids in Khat-treated rats.  相似文献   
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Background:The polysialylated neural cell adhesion molecule (PSA-NCAM) is expressed in developing brain. Fetal brain damage is caused by different conditions such as seizure and hypoxia. The present study was designed to investigate the effect of maternal seizures on the number of PSA-NCAM positive cells in pup''s hippocampus. Methods: Female Wistar rats were divided into four groups: (a) kindled rats which received PTZ (40 mg/kg, i.p.) during pregnancy from embryonic day 14-19 (E14-E19) every 48 h, (b) kindled rats which did not receive PTZ during pregnancy, (c) non-kindle, pregnant rats which received PTZ injection (40 mg/kg, i.p.) during pregnancy from E14 to E19 every 48 h, and (d) non-kindle, pregnant rats which received injection with an equal volume of normal saline as sham controls. At postnatal day 14 (PD14), rat pups were perfused, and their brain were fixed, embedded and coronal sections stained by immunohistochemistry method. The number of PSA-NCAM positive cells per unit area in the pup''s hippocampus was counted. Results: The number of PSA-NCAM positive cells in the CA1, CA3, and DG fields of pup''s hippocampus, which was obtained from mothers who experienced PTZ injection during pregnancy, was decreased approximately 2.6 (P = 0.001), 2 (P = 0.001), and 2.1 (P = 0.001) times compared with non-PTZ treated maternal groups, respectively. Conclusions: Our study showed that maternal seizures reduced the number of neurons and also PSA-NCAM positive cells per unit area in the offspring hippocampus that it may cause impairment in hippocampal functions.Key Words: Epilepsy, Polysialylated neural cell adhesion molecule (PSA-NCAM), Hippocampus, Seizures  相似文献   
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