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《生命世界》2006,(1):34-37
沙皮犬(Shar-Pei)世界上最稀少的犬,原产我国广东。至今已有2000多年历史。因为皮肤宽松多褶、毛短而硬、酷似沙皮而得名。被毛短密、粗硬、颜色有浅黄、宗黄和米色、黑色等。体高46~51厘米。体重18~25千克。头硕大呈方形,嘴部宽长,舌头为特殊的紫蓝色,耳朵小并且向前下垂,眼睛深邃,凹藏于眼窝内。脖颈短而粗壮。躯干呈圆筒状。四肢结识,尾巴上扬。全身肌肉发达。沙皮犬从外表看似沉郁、凝重,但性格顽皮,忠实可爱。它们是原始的、充满热情的犬。在生人面前它们显得拘谨、警惕,随时做好防御的准备,但它们决不会主动发动攻击。它们还是一种讲卫生的家庭宠物犬。 相似文献
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杨钟健院士离开我们整整30年了。他的得意门生、亲密朋友刘东生院士也于去年离开了我们,他们间的深情厚谊令人们永远传颂。刘东生1942年毕业于西南联合大学地质地理气象系。早年曾从事抗日救亡工作。1946年2月进入重庆北碚经济部中央地质调查所。7月,他随该所迁回南京。当年年底,李春昱所长找刘东生谈话,对他说:“现在工程地质很重要。这在将来铁路、水坝等工程里是迫切需要的。……”李所长最后提出建议刘东生也从事工程地质研究。 相似文献
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石吕平 《中国生物工程杂志》1982,2(3):43-44
五年来,在美国先后出现了一百五十个从事生物工艺学研制的公司。这些公司生意兴隆、财政富裕。在欧洲各国成立的生物工艺学公司也是如此。毫无疑问,生物工艺学具有美好的前景。财政界已开始认识到发展生物工艺学工业的重要意义。 相似文献
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《生物化学与生物物理进展》2014,(11)
<正>什么是good science?Good science也许被低估了。它可能不是那么华丽炫目,但是它带来革新。它开启了新的可能性。它告知,它启发,它创造。快来加入Takara和Clontech,一次一个实验,一起传颂这些生命科学研究的故事,是它们把世界变得更美好。科学领域,每个决定都有着深远的影响…每个时刻都是一个机遇,把一个实验最深的意义挖掘出来。决定很重要,无论是实验设计还是数据分析。这是我们通过经验确认的;我们是科学家。 相似文献
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Removal of oil by walnut shell media 总被引:3,自引:1,他引:2
Studies were conducted to evaluate the oil sorption capacities of walnut shell media. Sorption capacity is the weight of oil picked up by unit weight of a sorbent. Initial oil pick-up by walnut shell media on pure oil and oil on aqueous medium was evaluated. Batch kinetic studies were conducted to evaluate the equilibrium time required by walnut shell media for sorbing oil. For pure oil medium, sorption capacities of 0.30g/g, 0.51g/g and 0.58g/g were obtained for standard mineral oil, vegetable oil and DoALL Bright-Edge oil, respectively. The results showed sorption capacities of 0.56g/g, 0.58g/g and 0.74g/g for standard mineral oil, vegetable oil and DoALL Bright-Edge oil, respectively, for oil on aqueous medium. It was found that sorbed oil could be recovered from walnut shell media by applying pressure. The study showed that walnut shell media can be used as a sorbent for oil removal. 相似文献
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饲料氧化鱼油引起草鱼肠道结构损伤、通透性增加 总被引:1,自引:0,他引:1
为了探讨饲料氧化鱼油对草鱼(Ctenopharyngodon idellus)肠道组织结构及其通透性的影响, 本实验以豆油、鱼油及氧化鱼油作为饲料脂肪源, 分别设计鱼油组(6F)、豆油组(6S)、2%氧化鱼油(4S2OF)、4%氧化鱼油(2S4OF)及6%氧化鱼油(6OF) 5组等氮、等能的半纯化饲料。经72d池塘网箱养殖后, 实验结果显示: (1)氧化鱼油显著增加(P0.05)草鱼血清和肠道MDA含量、增加肠道GSH含量(P0.05), 但随氧化产物含量上升GSH含量出现下降。(2)氧化鱼油会显著降低肠道内胆汁酸的含量(P0.05)。(3)氧化鱼油会显著增加肠道绒毛中杯状细胞的数量(P0.05), 且随着氧化产物的增加, 肠道微绒毛高度呈现先上升后下降趋势。(4)氧化鱼油会导致肠道紧密连接间隙增大, 增加肠道通透性, 使血清中D-乳酸及内毒素含量显著增加(P0.05)。结果表明, 饲料中鱼油氧化产物损伤了草鱼肠道组织结构, 尤其是肠道上皮细胞紧密连接结构损伤严重, 从而破坏了肠道黏膜的机械屏障功能, 使肠道通透性显著增加, 肠道细菌内毒素等发生转移。鱼油氧化产物会引起草鱼肠道氧化与抗氧化应激反应, 干扰草鱼肝-肠正常胆汁酸循环, 致使草鱼肠道胆汁酸不足。 相似文献
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Process optimization for extraction of carotenoids from shrimp waste with vegetable oils 总被引:1,自引:0,他引:1
Shrimp waste is an important source of natural carotenoid. Studies were carried out to determine the extraction yield of shrimp waste carotenoids in different vegetable oils. Highest yield was obtained by extraction using refined sunflower oil compared to groundnut oil, gingelly oil, mustard oil, soy oil, coconut oil and rice bran oil. The extraction yield of carotenoids in sunflower oil was significantly influenced by level of oil to waste (p < 0.05), time (p < 0.01) and temperature (p < 0.001) of heating waste with oil before centrifugation to separate pigmented oil. A regression equation was derived for carotenoid yield as a function of time of heating, temperature of heating and oil level to waste. The optimized conditions for extraction of shrimp waste carotenoids in sunflower oil were determined to be oil level to waste of 2, temperature of 70 degrees C and heating time of 150 min. 相似文献
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Characterization of QTL for oil content in maize kernel 总被引:2,自引:0,他引:2
Yang X Ma H Zhang P Yan J Guo Y Song T Li J 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2012,125(6):1169-1179
Kernel oil content in maize is a complex quantitative trait. Phenotypic variation in kernel oil content can be dissected into its component traits such as oil metabolism and physical characteristics of the kernel, including embryo size and embryo-to-endosperm weight ratio (EEWR). To characterize quantitative trait loci (QTL) for kernel oil content, a recombinant inbred population derived from a cross between normal line B73 and high-oil line By804 was genotyped using 228 molecular markers and phenotyped for kernel oil content and its component traits [embryo oil content, embryo oil concentration, EEWR, embryo volume, embryo width, embryo length, and embryo width-to-length ratio (EWLR)]. A total of 58 QTL were identified for kernel oil content and its component traits in 26 genomic regions across all chromosomes. Eight main-effect QTL were identified for kernel oil content, embryo oil content, embryo oil concentration, EEWR, embryo weight, and EWLR, each accounting for over 10?% of the phenotypic variation in six genomic regions. Over 90?% of QTL identified for kernel oil content co-localized with QTL for component traits, validating their molecular contribution to kernel oil content. On chromosome 1, the QTL that had the largest effect on kernel oil content (qKO1-1) was associated with embryo width; on chromosome 9, the QTL for kernel oil content (qKO9) was related to EEWR (qEEWR9). Embryo oil concentration and embryo width were identified as the most important component traits controlling the second largest QTL for kernel oil content on chromosome 6 (qKO6) and a minor QTL for kernel oil content on chromosome 5 (qKO5-2), respectively. The dissection of kernel oil QTL will facilitate future cloning and/or functional validation of kernel oil content, and help to elucidate the genetic basis of kernel oil content in maize. 相似文献
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几种典型植物精油的化学成分与其抗菌活性 总被引:4,自引:0,他引:4
【目的】植物精油萃取自天然植物, 因具有抗菌活性, 近年来受到广泛关注。论文的目的是分析植物精油的化学成分, 测试其抗菌活性, 并研究其化学成分与抗菌活性之间的联系。【方法】实验选取了肉桂、山苍子、丁香、香茅、迷迭香和大蒜精油等6种典型植物精油, 通过气质联用分析方法研究了其化学组分, 并通过污染食物技术研究了其对黑曲霉和绳状青霉的抗真菌活性, 以及对大肠杆菌和金黄色葡萄球菌的抗细菌活性。【结果】气质联用分析结果表明, 肉桂、山苍子、香茅和迷迭香等4种植物精油的化学成分主要是醛类和醇类, 丁香精油的主要化学成分是丁香油酚, 大蒜精油化学成分基本上都是含硫的醚类, 其中二烯丙基三硫醚(大蒜素)含量最高。抗菌活性结果显示, 不同植物精油的抗菌活性不同, 6种植物精油的抗真菌活性由强到弱依次为: 肉桂>大蒜>丁香>山苍子=香茅>迷迭香, 抗细菌活性由强到弱依次为: 肉桂>山苍子>丁香>香茅=迷迭香>大蒜。【结论】植物精油的抗真菌、细菌活性与其化学组分密切相关, 肉桂、山苍子、香茅和迷迭香等4种精油的抗菌活性可能主要与其化学成分中的醛类和醇类有关, 丁香精油较高的抗菌活性可能主要源于丁香油酚; 大蒜精油具有高效的抗真菌活性主要源于其化学成分中的含硫醚。不同植物精油化学成分不同, 抗真菌、细菌活性也不同, 表明其可能有不同的抗真菌与抗细菌机制。 相似文献
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Summary Liverworts are characterized by the possession of typical cell elements, the oil bodies. In the submerse, thalloid liverwortRiella helicophylla (Sphaerocarpales) oil bodies are existing in idioblastic cells only, called oil body cells. Each oil body cell contains only one oil body. The oil body originates from small vacuoles. Their membranes are extremely high in contrast and asymmetric. The lipophilic substances are probably produced inside the oil bodies. At the end of the development of an oil body cell lipophilic and hydrophilic material will be separated from each other inside the oil body. The result is an oil body, consisting of one large spherical oil globule surrounded by a thin layer of hydrophilic matrix. 相似文献
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微生物强化采油(microbial enhanced oil recovery,MEOR)是近年来在国内外发展迅速的一项提高原油采收率技术。微生物在油藏中高效生产表面活性剂等驱油物质是微生物采油技术成功实施的关键之一。然而,油藏的缺/厌氧环境严重影响好氧表面活性剂产生菌在油藏原位的生存与代谢活性;油藏注空气会增加开采成本,且注入空气的作用时效和范围难以确定。因此,开发厌氧产表面活性剂菌种资源并强化其驱油效率对于提高原油采收率具有重要意义。本文综述了国内外近年来利用厌氧产表面活性剂微生物提高原油采收率的研究进展,简述了微生物厌氧产表面活性剂的相关驱油机理、菌种资源开发现状以及油藏原位驱油应用进展,并对当前的研究提出了一些思考。 相似文献
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The development of oil bodies and oil droplets in fruits of olive was examined at the ultrastructural level. Both oil bodies that form in young fruits and oil droplets that develop with fruit maturation are cytoplasmic bodies. The formation of the small oil bodies occurs in localized regions of the cytoplasm. These bodies are closely associated and fuse together, forming a small oil droplet that protruded against and indented the vacuolar membrane. As the fruit matures, new oil bodies appear to form and fuse with the oil droplet, resulting in the formation of a single large oil droplet of about 30 μm in diameter in most mature mesocarp cells. The cytoplasmic region where the oil bodies formed had a granulate, ultrastructural appearance, and cytoplasmic components such as membranes and ribosomes were noticeably absent in these regions. The granulate material coated the oil bodies and oil droplets, and appeared as a thin, compressed band between the round inner surface of the droplets and the indented tonoplast. We suggest that this granulate material is involved in the synthesis of the oil and, with enlargement of the oil bodies, this coat becomes thinner in regions where they are closely associated, resulting in zones where confluence of the oil occurs. 相似文献
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Six essential oils: asteraceae oil, rutaceae oil, mentha piperta oil, carvacryl oil, citronella oil, and eucalyptus oil were tested for evaluation of their repellent effects against Aedes albopictus mosquitoes under laboratory conditions. Only citronella oil and eucalyptus oil were tested with human beings. There was considerable protection for mice. Carvacryl oil (7%) provided 100% protection for mice after 7 h. Eucalyptus oil (15%) gave protection to humans for least 3 h; the protection time was prolonged to 5 h after adding 5% vanillin. The mixture could be developed into a practical product after the field evaluation. 相似文献
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为了探讨饲料氧化鱼油对草鱼(Ctenopharyngodon idellus)肝胰脏组织结构及其功能的影响, 研究以豆油、鱼油及氧化鱼油作为饲料脂肪源, 分别设计鱼油组(6F)、豆油组(6S)、2%氧化鱼油(4S2OF)、4%氧化鱼油(2S4OF)及6%氧化鱼油(6OF)5组等氮、等能的半纯化饲料, 在池塘网箱中养殖72d。结果显示: 氧化鱼油显著增加草鱼血清ALB、GLB、MDA和GSH含量(P0.05), 显著降低肝胰脏GSH和SOD含量(P0.05); 氧化鱼油会显著增加草鱼肝胰脏指数及肝胰脏脂肪含量(P0.05), 且草鱼血清TG含量显著上升(P0.05), HDL/LDL显著下降(P0.05); 氧化鱼油使血清及肝胰脏TC含量显著增加(P0.05), 血清TBA显著下降(P0.05), 肝胰脏TBA显著上升(P0.05); 氧化鱼油会引起草鱼脂肪肝, 损伤肝胰脏细胞线粒体, 并导致肝胰脏细胞纤维化和组织萎缩。结果表明: 饲料添加氧化鱼油会引起草鱼氧化应激, 并降低草鱼肝胰脏抗氧化能力; 扰乱草鱼肝胰脏脂肪代谢, 引起脂肪肝; 影响胆汁酸肝肠循环, 使胆汁酸在肝胰脏中堆积, 并损伤肝胰脏细胞线粒体, 最终增加草鱼肝胰脏脂肪性肝炎发生率。 相似文献