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为了探讨蓖麻油不皂化物是否具有激素效应,以及蓖麻油不皂化物与蓖麻油的抗生育活性的关联性,分别用剂量为100 mg/kg·d、 200 mg/kg·d、 500 mg/kg·d的蓖麻油不皂化物灌胃小鼠来检测其抗生育活性,并通过幼鼠子宫实验和E-SCREEN实验来检测蓖麻油不皂化物是否具有雌激素效应.结果 表明:蓖麻油不皂化物对成年小鼠具有明显的抗生育效果.在未成熟小鼠子宫实验中,当灌胃剂量为500 mg/kg·d时,表现出明显的雌激素效应;但是E-SCREEN实验结果中,蓖麻油不皂化物却未表现出雌激素效应.结论 :虽然在E-SCREEN实验中蓖麻油不皂化物不表现出雌激素效应,但是在动物个体实验中,其表现出的雌激素样作用同其抗生育作用具有一定的联系性. 相似文献
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为了制备包埋率高、稳定性好的火麻仁油微胶囊,拓展其在食品领域的应用范围,以火麻仁油为芯材、单双脂肪酸甘油酯为乳化剂、酪蛋白酸钠为壁材、固体玉米糖浆为填充剂、柠檬酸钠为缓冲盐、抗坏血酸棕榈酸钠为抗氧化剂,通过喷雾干燥法制备60%载油率的火麻仁油微胶囊,以微胶囊包埋率为响应值,在单因素实验的基础上,以干物浓度、进风温度、出风温度为实验因素,采用Box-Behnken响应面分析法进行优化。随后通过扫描电镜观察火麻仁油微胶囊表面形态结构,以确定包埋效果。并利用油脂氧化分析仪检测火麻仁油微胶囊的氧化稳定性。研究确定微胶囊的最佳工艺条件为:干物浓度42%、进风温度168 ℃、出风温度74 ℃,在此条件下制备得到的火麻仁油微胶囊包埋率可达92.15%。通过扫描电镜观察到火麻仁油微胶囊表面圆滑无裂痕,表明火麻仁油微胶囊包埋效果比较理想。经油脂氧化分析仪测定,与对照组(火麻仁油)相比,试验组(火麻仁油微胶囊)的氧化诱导期时间较长,能够达到30 h以上,说明通过对火麻仁油进行微胶囊包埋可以较大程度地提高油脂的稳定性。研究结果为火麻仁油在食品工业领域的开发和应用提供了理论支持。 相似文献
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目的:考察粒径对微胶囊强度及微囊化细胞生长代谢的影响,为制备性能优良的生物微胶囊提供实验依据。方法:制备不同粒径的凝胶珠,测定其在相同成膜条件下的球磨强度,进而用台盘蓝拒染法测定微囊化细胞的增殖及活率。结果:小粒径的微胶囊具有更厚的微囊膜及更高的球磨强度,另外小粒径微胶囊培养细胞能够获得更多的细胞数(350μm,570μm和900μm微囊内的细胞数量分别为:5.67×107、4.71×107和3.89×107/mL microcapsule,P<0.05)及更高的细胞活率(350μm、570μm和900μm微胶囊的细胞活率分别为:83.70%、67.64%和75.73%,P<0.05)。结论:粒径能影响微胶囊的强度及微囊化细胞的生长、代谢。 相似文献
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膜材与制备过程对血红蛋白微胶囊粒径和包埋率的影响 总被引:3,自引:0,他引:3
以单甲氧基聚乙二醇聚乳酸共聚物(PELA)为膜材用复乳溶剂扩散法制备了包含牛血红蛋白(BHb)的微胶囊,微胶囊中BHb的P50和Hill系数分别为3 466 Pa和2.4左右,接近于天然BHb的生物活性。研究发现膜材种类对BHb微胶囊包埋率和粒径的影响最大,使用MPEG2000为亲水性嵌段的PELA共聚物时,包埋率最高,达到90%以上,粒径为3~5 μm左右;随着膜材浓度的增大,微胶囊包埋率和粒径均增加;随着外水相NaCl浓度的增大,微胶囊包埋率升高、粒径减小;随着外水相稳定剂PVA浓度的增大,微胶囊粒径减小,包埋率先升高后降低,在较低浓度下(10 g/L、20 g/L)包埋率较高;初乳化搅拌速率的增大,有利于包埋率的提高,但对粒径影响不大;复乳化搅拌速率的影响较复杂,当复乳液体积较大时,复乳化搅拌速率对微胶囊制备的影响规律性不明显。当固定膜材和初乳化搅拌速率时,包埋率和粒径之间存在着类似抛物线的关系,包埋率随着粒径的减小而降低。 相似文献
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目的:通过单次灌肠和皮肤致敏联合灌肠,构建2,4,6-三硝基苯磺酸(TNBS)诱导的炎症性肠病小鼠模型,探讨最佳造模方法,并分析影响模型构建的因素。方法:55只SPF雄性BALB/c小鼠随机分为7组,包括对照组、不同剂量TNBS(100、150、175、200、225 mg/kg)单次灌肠组及皮肤致敏联合灌肠组。于造模后5 d处死各组小鼠,观察结肠大体形态并评分;取病变处进行石蜡包埋切片,HE染色,并进行病理组织学评分。结果:100、150 mg/kg TNBS单次灌肠组动物未见明显的溃疡形成;其余剂量组动物均有不同程度的溃疡形成,成模率与剂量成正比,其中225 mg/kg剂量组动物成模率为100%,但病变较重、病变不均一且偶有小鼠眼睛失明的副作用出现。皮肤致敏联合灌肠组动物均有溃疡形成,成模率100%,病变适中且未发现小鼠眼睛失明的副作用。结论:175-225 mg/kg TNBS单次灌肠及皮肤致敏联合TNBS灌肠均可制备小鼠炎症性肠病模型,但皮肤致敏联合TNBS灌肠制备的炎症性肠病模型成模率高,病变适中,模型稳定,适合用作科学研究模型。 相似文献
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目的制备保加利亚乳杆菌NQ2508双层微胶囊,并考察其包埋产率和耐胃酸能力。方法以保加利亚乳杆菌NQ2508改性淀粉微胶囊为研究对象,以聚丙烯酸树脂为包衣材料,采用流化床底喷工艺制备微胶囊,通过正交试验考察进风温度、雾化压力、进风风量、包衣增重4个因素对微胶囊化的影响。结果最佳工艺条件为进风温度50℃、雾化压力2.0bar、进风风量35m3/h、包衣增重30%,在该工艺条件下制得的微胶囊包埋产率为50.2%,微胶囊经人工胃酸处理后活菌存活率为39.2%。结论工艺优化后制得保加利亚乳杆菌NQ2508双层微胶囊的包埋产率和耐酸能力均较高。 相似文献
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红掌的离体组织培养与快速繁殖 总被引:7,自引:0,他引:7
武爱龙 《基因组学与应用生物学》2010,29(1)
本研究从红掌组培的实用化生产出发,在不同激素成份及浓度水平下,以MS为基本培养基,红掌的叶片或叶柄为外植体进行组培快繁试验。实验结果表明:MS+6-BA1mg/L+2.4-D0.1mg/L为最佳诱导培养基,诱导率可达89%以上,红掌的叶片诱导效果比叶柄较为理想。最适分化培养基为:MS+BA1.5mg/L+NAA0.1mg/L,其分化率为93%;继代增殖培养基为MS+6-BA2mg/L+NAA0.2mg/L,增殖系数达7.1;适合生根诱导培养基为l/2MS+NAA0.2mg/L,生根率达96.5%以上。生根苗田间移栽后成活率可达95%以上。 相似文献
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目的:肉豆蔻精油因刺激性气味及易挥发的特点限制了其在食品中的应用,为提高肉豆蔻精油的适用性,利用喷雾干燥技术制备肉豆蔻精油微胶囊。方法:以辛烯基琥珀酸淀粉酯/麦芽糊精(OSA/MD)为复合壁材制备微胶囊,采用气相色谱—质谱联用(GC MS)法测定了包埋前后肉豆蔻精油的成分组成及相对含量,并对微胶囊稳定性进行考察。结果:制备的肉豆蔻精油微胶囊包埋率和保留率分别达到99.28%和88.15%,且40℃时保持稳定。结论:以辛烯基琥珀酸淀粉酯/麦芽糊精(OSA/MD)为复合壁材,利用喷雾干燥技术制备肉豆蔻精油微胶囊包埋效果好,且稳定性得到明显提高。 相似文献
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福建野生紫芝资源开发利用Ⅱ.“闽紫96”(中国灵芝) 总被引:3,自引:1,他引:2
由福建野生紫芝人工驯化得到的栽培菌株“闽紫96”,子实体中型,菌盖大小7.0~9.0×10.0~17.3cm,其担孢子形态饱满,6.84~7.37×10.26~11.05μm,较灵芝担孢子大;标本(HMAS 77207)经鉴定确认为紫芝(Ganoderma siruense J.D.Zhao,L.W.Hsu et X.Q.Zhang),是符合《中华人民共和国药典》记载的灵芝药材的来源菌物。2004-2005年,采用阔叶树枝桠材栽培“闽紫96”,推广栽培面积860m~3(菌材),平均年产量为12.70 kg/m~3(干品/菌材)。将“闽紫96”子实体超微粉碎加工成300目超细粉。扫描电镜观察可见:其超细粉呈纤维状,以分散、破碎的茵丝片段形态存在,长度范围为10~50μm,直径1.2~4.5μm不等;激光粒度检测结果表明:超细粉的表面积达到227.54 m~2/kg,D97=63.8μm。化学成分分析结果表明:“闽紫96”超细粉的水分、粗蛋白、粗脂肪、粗纤维、总糖、灰分及多糖含量分别为4.2 g/100g、10.84g/100g、3.71 g/100g、36.5g/100g、30.2g/100g、1.7 g/100g和1.3 g/100g;所含17种氨基酸总量为9.30 mg/100mg,其中必需氨基酸占65.7%;其脂肪酸构成以油酸(45.5%)、亚油酸(27.7%)及棕榈酸(18.8%)为主。此外,其重金属元素Pb,As,Hg,Cd等含量分别为<0.2 mg/g、0.13 mg/g、0.072 mg/g、0.24 mg/g,符合国家商务部《药用植物及制剂外经贸绿色行业标准》(WM/T2-2004)要求。 相似文献
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《生物加工过程》2010,(1)
利用四乙氧基硅烷(TEOS)原位水解法将S iO2掺杂于海藻酸(ALG)凝胶中,通过双交联制备出新型ALG-S iO2杂化凝胶以固定化洋葱伯克霍尔德菌脂肪酶。结果表明,固定化酶的最优条件:质量分数为2.0%的ALG、0.2 mol/L CaC l2、V(ALG)/V(TEOS)为5、加酶量为1 g ALG加100 mg酶粉、固定化60 m in、采用直径为0.8 mm的针头滴定、真空冷冻干燥。在此条件下,酶蛋白的包埋率可达100%,酶活回收率可达91%。固定化酶的最适pH为8.0,最适作用温度为50℃,重复使用8次后,酶活性仍能保持80%以上。ALG-S iO2杂化凝胶的场扫描电镜(FESEM)观察发现凝胶的整体构造仍然是海藻酸凝胶骨架;与ALG凝胶平滑的内部相比较,杂化凝胶仍具有完整的网络结构,但内部更为粗糙,结构更为致密。 相似文献
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Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis
It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis. 相似文献
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RICHARD E. NORRIS 《Botanical journal of the Linnean Society. Linnean Society of London》1991,106(1):1-40
Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera. 相似文献
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JOAN VALUÈS MONTSERRAT TORRELL NÚRIA GARCIA JACAS 《Botanical journal of the Linnean Society. Linnean Society of London》2001,137(4):399-407
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted. 相似文献
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肝癌中HBV和HCV基因和抗原的分布及意义 总被引:1,自引:0,他引:1
采用原位分子杂交方法检测HCV
RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV
RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV
RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV
X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV
C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细 相似文献
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H.-R. GREGORIUS 《Biological journal of the Linnean Society. Linnean Society of London》1984,23(2-3):157-165
For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment. 相似文献
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment. 相似文献