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The European hare Lepus europaeus and the European rabbit Oryctolagus cuniculus are sympatric in many areas of the world. They are medium-sized herbage-feeding lagomorphs and trophic competitors. Both species feed on twigs under extreme and perhaps limiting conditions. To ascertain whether fine niche separation mechanisms occur, several comparative tests of digestive function were undertaken on samples of animals drawn from sympatric populations. The weights of the organs constituting the abdominal alimentary canal, the rates of passage and the extent of trituration of dietary markers intended to mimic twigs, and the digestibility of fibre, protein, and fat were compared. Both the stomach and the caecum of the hare were significantly smaller as a proportion of body weight, and this would result in a higher power–weight ratio. Both species rapidly passed the digestive marker, but passage was significantly faster in the hare. The rabbit chewed twig-like material with a scissor cutting and crushing action, whereas the action of the hare included a stripping action that would more efficiently access soluble carbohydrates stored in vascular rays. Both species were poor digesters of fibre, but digestibility of hemicelluloses was significantly greater in the rabbit. The faeces of both species of lagomorphs contain nutrients that can be attractive to more efficient fermenters of plant fibre, and consumption of those faeces may confound lagomorph population surveys that rely on dung counts. 相似文献
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采用硅胶、Sephadex LH-20、HPLC半制备等方法,对高山柏(Sabina squamata)的化学成分进行了研究。结果表明:从高山柏植物中共分离得到9个化合物。这些化合物经过波谱数据分析并结合文献对照,分别鉴定为山达海松酸(1),3β-羟基山达海松酸(2),柳杉酚(3),5-羟基-7,4'-二甲氧基黄并酮(4),去甲丁香色原酮(5),柏木双黄酮(6),十九烷酸-2,3-二羟丙酯(7),胡萝卜苷(8),β-谷甾醇(9)。以上所有化合物均为首次从该植物中发现。研究结果丰富了高山柏的化学成分内容,为其今后的开发与利用提供了科学依据。 相似文献
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S. Devillard J. Aubineau F. Berger Y. Lonard A. Roobrouck S. Marchandeau 《Mammalian Biology》2008,73(2):128-137
Despite their pest status in numerous areas throughout the World, the populations of European rabbits (Oryctolagus cuniculus) have strongly decreased in South Western Europe since the mid-20th century. Such a decrease constitutes a major threat on top predators and calls for a better understanding of its mechanisms to provide suitable management responses. Infectious diseases have been invoked as the main responsible factors, but they cannot by themselves explain the magnitude of this decrease. Habitat fragmentation may indeed act as a synergetic factor, and habitat use studies are needed to better understand the impact of fragmentation on rabbit population dynamics. We investigated the variability of home range size with respects to age, sex and season in three wild populations of rabbits using telemetry. Home ranges were smaller in the highest density populations (7333 and 6878 vs. 20,492 m2) suggesting differences in habitat quality between the populations. In addition, home range sizes were larger during the reproductive season for both sexes, and adults tended to have smaller home ranges than juveniles. Clearly, the home range sizes reported here were smaller than those previously reported in rabbits. 相似文献
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Raquel Monclús Marta Arroyo Ana Valencia Francisco Javier de Miguel 《Journal of Ethology》2009,27(1):153-156
One of the functions of chemical communication is territorial signalling. To achieve this, animals should mark their territories
in a manner that increases the detectability of the marks, thereby maximising the probability that other animals detect the
scent marks. In this study, we focused on the scent-marking behaviour of red foxes in relation to the abundance of their main
prey, the European rabbit, in a suburban forest in Madrid, Spain. Our results reveal that foxes scent-marked more and increased
the detectability of their marks in areas of higher rabbit density. It would appear that foxes defend food resources from
competitors by increasing the number and the detectability of their scent marks. 相似文献
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分离鉴定爵床科观音草属植物山蓝的化学成分。采用硅胶柱色谱、重结晶方法对山蓝乙醇提取物进行分离纯化,利用红外、质谱、核磁共振技术进行结构鉴定,得到15个化合物,分别为二十八醇(1),硬脂酸(2),β-谷甾醇(3),豆甾醇(4),棕榈酸(5),月桂酸(6),尿囊素(7),棕榈醇(8),芝麻素(9),齐墩果酸(10),β-胡萝卜苷(11),尿嘧啶(12),腺嘌呤(13),十八烷基葡萄糖苷(14),柠檬酸(15)。除β-谷甾醇,豆甾醇和β-胡萝卜苷外,其余12个化合物均为首次从该植物中分离得到。 相似文献
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对大戟科巴豆属植物毛果巴豆的根进行化学成分研究,并利用多种色谱方法分离得到11个化合物,根据理化性质和波谱学手段鉴定了结构。它们分别是3-乙酰高根二醇(1),3-乙酰齐墩果酸(2),ilexgenin A (3),(24S)-24-ethylcholesta-3β,5α,6β-triol(4),邻苯二甲酸二丁酯(5),邻苯二甲酸二异丁酯(6),邻苯二甲酸正丁异丁酯(7),Aralia cerebroside(8),熊果酸(9),β-谷甾醇(10),胡萝卜苷(11)。所有化合物均为首次从该植物中分离得到。 相似文献
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南山茶果皮化学成分的研究 总被引:1,自引:0,他引:1
反复采用硅胶柱色谱法、Sephadex LH-20柱色谱法、ODS柱色谱法、反复重结晶等方法对南山茶果皮的化学成分进行分离纯化,并通过理化常数测定和波谱分析等方法进行结构鉴定。从南山茶果皮中分离并得到了10个化合物,分别鉴定为槲皮素(1)、山奈酚(2)、原儿茶酸(3)、山柰酚-3-O-β-D-葡萄糖基-(6→1)-2′′′,4′′′-O-二乙酰基-α-L-鼠李糖基-(3→1)-2′′′′,3′′′′,4′′′′-O-三乙酰基-α-L-鼠李糖苷(4)、山柰酚-3-O-β-D-葡萄糖基-(6→1)-4′′′-O-乙酰基-α-L-鼠李糖基-(3→1)-3′′′′-O-乙酰基-α-L-鼠李糖苷(5)、3-甲氧基鞣花酸(6)、鞣花酸(7)、羽扇豆烷醇(8)、β-谷甾醇(9)和胡萝卜苷(10)。化合物2、6、7均为首次从南山茶中分离得到,其中化合物6、7为首次从山茶属植物中分离得到。 相似文献
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采用常压柱色谱和重结晶相结合的分离方法,从木奶果的茎叶提取物的乙酸乙酯部分中分离得到8个化合物,通过波谱方法及与已知样品对照的手段鉴定它们为(2S,3S,4R)-2-[(2R)-2-hydroxytetracosanoyl-amino]-1,3,4-octadecanetriol(1),Aralia cerebroside(2),(24S)-24-ethylcholesta-3β,5α,6β-triol(3),Stigmast-4-en-6β-ol-3-one(4),7-oxo-β-sitosterol(5),7α-methoxy-sigmast-5-en-3β-ol(6),β-sitosterol(7),daucosterol(8)。化合物1-6为首次从该种植物中发现的。 相似文献
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Philip E. Mirkes Sally A. Little Leanne Cornel Michael J. Welsh Thu-Na Ngo Laney Frances H. Wright 《Molecular reproduction and development》1996,45(3):276-284
Previously we reported that eight proteins were reproducibly induced in postimplantation rat embryos exposed to a brief heat shock (43°C, 15 min). The major heat-inducible rat embryo protein has now been identified as heat shock protein 72 (Hsp 72). In addition, the induction of Hsp 72 is temporally correlated with induction of thermotolerance. One of the other rat embryo proteins previously shown to be induced by elevated temperature is a heat shock protein of approximately 27 kilodaltons (Hsp 27). In this report we show that this protein is recognized by an antibody directed against a conserved peptide sequence of Hsp 27. Unlike Hsp 72, Hsp 27 is constitutively expressed in the rat embryo in the absence of any thermal stress; however, the level of Hsp 27 is increased approximately 2–3-fold after thermal stress (43°C, 10 min). Immunohistochemical analysis revealed that the constitutively expressed Hsp 27 is localized primarily to cells of the heart, cells that are uniquely resistant to the cytotoxic effects of hyperthermia. After thermal stress, Hsp 27 is expressed in all tissues of the embryo. Finally, our data show that Hsp 27 exists in the rat embryo as three major isoforms indicative of different phosphorylation states. Furthermore, most Hsp 27 in the heart is phosphorylated, whereas in the rest of the embryo, nonphosphorylated Hsp 27 predominates. After thermal stress, levels of phosphorylated isoforms increase dramatically in nonheart tissues of the embryo. Together, these results suggest that Hsp 27 may play a role in the development of thermotolerance in the postimplantation mammalian embryo. © 1996 Wiley-Liss, Inc. 相似文献
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葫芦茶地上部分化学成分的研究 总被引:1,自引:0,他引:1
运用多种色谱法进行分离纯化,并通过理化性质和波谱数据对化合物进行结构鉴定,研究葫芦茶地上部分的化学成分。结果表明:从葫芦茶地上部分分离并鉴定了13个化合物,分别为山柰酚(1)、山柰酚-3-O-α-L-鼠李糖苷(2)、山柰酚-3-O-β-D-葡萄糖苷(3)、山柰酚-3-O-β-D-芸香糖苷(4)、槲皮素-3-O-α-L-鼠李糖苷(5)、山柰酚-3-O-α-L-鼠李糖(1→6)-β-D-半乳糖苷(6)、槲皮素-3-O-β-D-葡萄糖苷(7)、槲皮素-3-O-α-L-鼠李糖(1→6)-β-D-半乳糖苷(8)、芦丁(9)、间苯三酚-O-β-D-葡萄糖苷(10)、对羟基桂皮酸(11)、RoseosideⅡ(12)、儿茶素(13)。其中化合物2、4、5、6、8、9、10、12为首次从该植物中分离得到。 相似文献
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红背山麻杆(Alchornea trewioides )为山麻杆属植物,作为传统的中药被用来减轻疾病和身体不适,但它的药效物质基础尚未完全清楚。为了全面掌握红背山麻杆药效物质基础,采用80%丙酮对其新鲜叶进行提取,并利用 MCI gel CHP 20P、Sephadex LH-20等色谱柱进行分离共得到9个化合物。这些化合物的结构经氢谱与碳谱比较分析鉴定为鞣花酸(1)、3-O-甲基没食子酸(2)、decarboxyellagic acid(3)、1-O-没食子酰基-β-D-葡萄糖(4)、1,6-二-O-没食子酰基-β-D-葡萄糖(5)、柯里拉京(6)、叶下珠鞣质 D(7)、furosonin(8)、老鹳草素(9)。其中化合物2~9均为首次从该属植物中分离得到。 相似文献
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菜蕨的化学成分研究 总被引:1,自引:0,他引:1
采用硅胶柱层析和凝胶柱层析对菜蕨的丙酮提取物进行分离纯化,首次从中分离得到10个化合物,通过波谱学数据并和已知化合物数据比较,鉴定它们分别为β-sitosterol(1),Stigmast-4-ene-6β-ol-3-one(2),Stigmast-4-ene-3,6-dione(3),Benzeneacetic acid(4),3β-Hydroxy-5α,8α-epidioxyergosta-6,22-diene(5),Stigraast-4-ene-3β,6β-diol(6),Stigmast-5-ene-3β,7α-diol(7),Stigmast-4-ene-6α-ol-3-one(8),Glycerol-1,3-dihexadecanoate(9)以及Daucosterol(10). 相似文献
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Demographic parameters of the European hare (Lepus europaeus) in southern Australia were investigated by dissecting hares shot by hunters during each month of the year. Gender, body weight, age, sucking, lactation, weight of the abdominal alimentary canal, weight of the left peri-renal fat body, pregnancy status, presence and counts of placental scars, litter size, and stage of gestation were recorded. From those data, growth rates, age at weaning, age and weight at puberty, date of conception, projected birth date, recruitment, survivorship, and the relationships between lactation and fat stores and alimentary capacity were determined.Fecundity of the southern Australian hares followed the seasonal pattern reported for northern hemisphere populations. However, output was lower per female and particularly per older female. Females began breeding at an earlier age such that recruitment into the southern Australian population was more dependent on females in their first year of life than on older females. Growth rates were comparable with European rates. Although high chill factors were apparently associated with higher leveret mortality, there was paradoxically higher overall mortality during the spring-early summer period of higher plant growth than in the late summer–winter period of lower plant growth and more extreme weather conditions. Fat was accumulated during pregnancy and would act as a buffer against the possibility of inadequate food availability during lactation, but hares increased the capacity of the alimentary canal during lactation and presumably with it their ability to assimilate energy to meet the demands of lactation. 相似文献