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1.
红香蕉苹果在适宜的成熟度采收,经^60Co-γ射线0.5kGy照射,剂量率低于10Gy/min处理后,在温度0-5℃,湿度85-95%,包装箱内衬无毒聚乙烯膜的条件下储存6个月,其硬度,主要营养成分,色,香,味及外观无显著性变化。  相似文献   

2.
利用(60)Co─γ射线辐照市售散装白洒(60°),处理剂量为0.8kGy、2.0kGy、4.0kGy,剂量率为3.33Gy/min,在贮存不同时间后,检验其理化及感官指标。结果表明,经γ射线辐照的白洒,总酸、总酯等有益成分均有不同程度增加,其感官指标也比对照组好,尤其以辐照剂量2.0kGy的处理组最佳,且辐照后贮存一定时间,其陈化效果更好。  相似文献   

3.
杜仲愈伤组织超低温保存的研究   总被引:5,自引:0,他引:5  
采用单因子比较、正交设计和均匀设计法,分别考察影响杜仲愈伤组织诱导、生长及其超低温保存的因素。试验表明:B5+NAA0.5mg/L+6—BA1mg/L有利于意伤组织诱导。MS+2.4—D3mg/L+6—BA0.5mg/L则有利于愈伤组织快速生长。超低温保存的最佳材料是2周龄的愈伤组织。愈伤组织超低温保存的较好冷冻保护剂是12.5%Gly+7.5%PEG+2.5g/LLH。  相似文献   

4.
通过用不同剂量的 ̄(60)Co—γ射线辐照硫磺软膏、鞣酸软膏、土肥氏软膏及辐照后贮藏效应的研究表明,γ辐照对软膏剂灭菌效果显著,杂菌存活量随辐照剂量及辐照后的贮藏时间增加而降低。对于上述三种软膏,最适辐照剂量为2.0—4.0KGy。  相似文献   

5.
褪黑素对大鼠海马神经元谷氨酸所致毒性的拮抗作用   总被引:3,自引:0,他引:3  
在大鼠海马脑片上电刺激Schaffer 侧支纤维, 胞外记录CA1 区锥体细胞层诱发群体锋电位(population spike,PS) , 观察灌流谷氨酸(Glu) 和褪黑素(MEL) 对PS的影响。结果显示:5-0 mmol/L浓度的Glu 可使PS值下降至对照值的4-1 % ; MEL(0-4 、0-5 和0-6 μmol/L) 与5-0 mmol/LGlu 混合给药,PS值分别变化为对照值的14-7 % 、105-2% 、24-3 % ; MEL(0-5 μmol/L) 、Glu (5-0 mmol/L) , 与赛庚啶(CDP,0-5 μmol/L) 混合给药,PS值下降至0 。上述结果提示,5-0 mmol/L浓度的Glu 有神经毒性作用, 但可为MEL拮抗, 这可能由5HT受体所介导。  相似文献   

6.
 以人肺癌细胞 P G 和人胃癌细胞 B G C 823 作为研究对象,利用 M T T 测定、3 H Td R 参入、流式细胞术、软琼脂培养、 Northern blot、 W stern blot 等实验方法,观察了稀土化合物氯化亚鈰( Ce Cl3)抑癌作用.结果表明, Ce Cl3 浓度为 005 m m ol/ L,01 m m ol/ L,05 m m ol/ L和 1 m m ol/ L可抑制 P G 细胞的增殖;浓度为 05 m m ol/ L和 1 m m ol/ L可抑制 P G 细胞 D N A 的合成,其 G1 期细胞比例增加而 S期细胞比例减少,在软琼脂中的生长能力降低,原癌基因 c m yc 和 c ras 表达降低,p16 蛋白质表达降低.而同样浓度的 Ce Cl3 对 B G C 823 细胞和正常细胞 2 B S未见影响.提示:稀土化合物抑制肺癌细胞 P G 的增殖以及降低其恶性度的作用机制可能与一些增殖相关的原癌基因的表达和细胞周期的调控有关,其确切的机理还需进一步的研究.  相似文献   

7.
用抗氟化物酸性磷酸酶(FRAP)法和显微测量,对大鼠腋神经一级传入纤维在脊髓胶状质(SG)的定位投射进行了定量分析。大鼠腋神经向SG的纵向投射主要在C5~C7,C5~C7各节段SG水平向“眉毛状反应带”宽所测均值(mm)分别为0.872、0.920、0.960,而腋神经向C5~C7各节段水平向投射所测均值(mm)分别在0.390~0.508、0.432~0.605、0.497~0.658的范围  相似文献   

8.
本文报道雌鼠及雌雄性小鼠分别受到0.15-1.56Gy~60Coγ-射线照射后,在不同时间进行同笼,取其胚胎观察形态、大小等并制备每个胚胎的染色体标本。分析胚胎细胞染色体数目异常、结构畸变及显性致死效应。结果表明,染色体数目异常发生率与剂量呈直线关系。单纯雌鼠受到1.07Gy照射后观察到平衡易位携带者的再现率为0.99%。雌雄鼠均受到1.07及1.56Gy照射后其F_1子代中平衡易位携带者的再现率皆为0.32%。雌雄鼠均受照射组中的显性致死率明显高于雌鼠受照射组,且剂量效应关系为直线相关  相似文献   

9.
为了充实和完善周围神经一级传入纤维向SG定位投射的定量分析,本文仍按跨神经节溃变原理,用FRAP法和显微测量方法对桡神经进行了研究。大鼠桡神经向SG的纵向投射为C5~T1。C5~T1各节段SG水平向“眉毛状反应带”长所测均值(mm)分别为0.834、0.884、0.930、0.876、0.788,而桡神经向C5~T1各节段SG水平向投射所测均值(mm)分别在0.337~0.449、0.354~0.553、0.366~0.654、0417~0.611、0.421~0.574的范围,显示了反应带从SG的中间区逐渐向外扩展  相似文献   

10.
姚素艳  张朝阳 《遗传学报》1994,21(3):188-192
1文报道雌鼠及雌雄性小鼠分别受到0.15-1.56Gt^60coγ-射线照射后,在不同时间进行同笼,取其胚胎观察形态、大小等并制备每个胚胎的染体标本。分析胚胎细胞染色体数目异常、结构畸变及显性致死效应。结果表明,染色体数目异常发生率与剂量呈直线关系。单纯雌鼠受到1.07Gy照射后观察到平衡易位携带者的再现率为0.99%。雌雄鼠均受到1.07及1.56Gy照射后观察到平衡易位携带者的再现率为0.99  相似文献   

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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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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   

18.
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   

19.
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   

20.
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   

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