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91.
用免疫荧光单克隆抗体对脊髓灰质炎病毒抗原表位的分析 总被引:1,自引:0,他引:1
用间接免疫荧光与中和试验筛选出来的抗脊髓灰质炎2型与3型不同毒株的12个单克隆抗体,其中3个仅有免疫荧光活性,9个具有中和与免疫荧光活性。用免疫荧光活性的单克隆抗体进行试验,发现它们在识别特异性抗原表位方面与中和性单克隆抗体相似,显示出株特异的、几个毒株共同特异的或型特异的抗原表位。根据表位分布关系及特征,可以用来鉴别型内毒株的特征、毒株的抗原分析、抗原变异的研究以及疫苗相关病例的鉴别。所得结果与中和性单克抗隆抗体及T1-寡核苷酸指纹图谱分析一致。而免疫荧光单克隆抗体识别抗原表位的活性范围比中和性单克隆抗体更广。另外还发现某些兼有荧光与中和两活性的同一个单克隆抗体,用不同方法(IF与NT)进行试验时,与相同毒株出现不同表位反应,这点是值得引起注意需待进一步证实的重要问题。 相似文献
92.
A group of 14 9-substituted derivatives of 6-benzylaminopurine (BA), including the alanine conjugate, oxygen heterocyclic
and alkyl derivatives, and compounds with a modified 9-ribose moiety, were assessed for their ability to retard soybean leaf
senescence. The 9-alanine conjugate was very weakly active, and only two compounds, 9-(2-tetrahydropyranyl)-BA (9THP-BA) and
9-(2-tetrahydrofuranyl)-BA (9THF-BA), proved to be considerably more effective than BA. The metabolism of these three BA derivatives
was determined to rationalize their differing activity. The alanine conjugate of BA was largely unmetabolized in leaf discs,
but 9THP-BA and 9THF-BA released free BA and were also debenzylated to 9THP-adenine and 9THF-adenine, respectively. The three
products of metabolism were identified by mass spectrometry. The enhanced activity of 9THP-BA and 9THF-BA, relative to that
of BA, is attributed to their greater stability and their ability to gradually release free BA. This released BA was less
susceptible to inactivation by alanine conjugate formation than was exogenous BA. The novel BA analogue 7-benzylaminooxazolo[5,4-d]pyrimidine,
in which the 9-NH is replaced by oxygen, was inactive at 100 μM.
For part II, see Zhang et al. 1987 相似文献
93.
下肢长骨骨重的非对称性 总被引:4,自引:0,他引:4
本文测量82副中国成年下股长骨即股骨,胫骨和腓骨的重量,在两侧骨重相差>1%时,则股骨、胫骨和腓骨及其三骨总重均以非对称性为多,均具有非常显著性差异(P<0.001)。除腓骨重具有明显侧别差异外,其余无显著性侧别差异,对腓骨侧差解释为:①腓骨主要机能是肌的附着,而下肢对踢和足趾取物具有明显的侧别差异;②以两侧骨重相差>1%时为非对称性的标准,由于腓骨绝对重量较小,在两侧相差<0.5克时即多属非对称性。 相似文献
94.
本文系用原子吸收光谱法测定了西安地区10例成人尸体和15例新生儿尸体的颅盖骨内Cu和zn的含量。结果求得成人颅骨中Cu正常含量(均数±标准差)为4.48±3.78mg/kg(干组织重);zn为597.05±472.54mg/kg。新生儿颅骨中Cu和zn的含量分别为1.96±0.76mg/kg;1160.38±859.71mg/kg。结果表明,成人颅骨内Cu含量高于新生儿,而成人颅骨内Zn含量显著低于新生儿。 相似文献
95.
Lean Han San Fernand Vedel Darasinh Sihachakr René Rémy 《Molecular & general genetics : MGG》1990,221(1):17-26
Summary Mesophyl protoplasts of two genotypes of cultivated tomato (Lycopersicon esculentum Mill.) and one of its wild relative species (Lycopersicon peruvianum Mill.) were fused by using electrofusion and polyethyleneglycol-induced fusion. Forty-three fertile tetraploid somatic hybrid plants, each deriving from separate calli, were recovered from both fusion procedures. Electrofusion appeared more efficient than chemical fusion for the production of somatic hybrids. These plants appeared morphologically similar, whatever the fusion procedure and tomato genotype. They had intermediate leaf, inflorescence, and flower morphology. After self-pollination, the hybrids set fruit of intermediate size and color. The hybrid nature of these plants was confirmed by isoelectric focusing of the Rubisco small subunits used as nuclear markers. L. esculentum and L. peruvianum were distinguished by means of two chloroplast markers: CF1-ATPase subunit as analyzed by isoelectro-focusing and ct DNA restriction patterns. All hybrids displayed both ct markers of only one parent with no biased transmission. Mitochondrial (mt) DNAs were prepared from flower buds by using miniaturized CsCl gradients. Preliminary analysis indicated that mt genomes from the hybrids all differed from those of both parents. mt DNA Sall restriction enzyme analysis revealed that all but two hybrids contained one novel fragment of 13.5 kb. Gene mapping experiments showed that the mt apocytochrome b and ATPase subunit 9 homologies in the somatic hybrid mt DNA resembled L. esculentum and L. peruvianum, respectively; the mt nad5 probe distinguished at least four distinct patterns in the hybrids. These results indicated that mt DNA rearrangements involving intergenomic recombinations occurred through protoplast fusion. A greater mt DNA polymorphism was induced with chemical fusion than with electrofusion. 相似文献
96.
Renée M. Borges 《Oecologia》1990,85(1):80-86
Summary The calcium ingestion of Malabar Giant Squirrels Ratufa indica (Sciuridae) was examined at two sites, Magod and Bhimashankar, in western India. In females at Magod a positive correlation was found between rates of calcium ingestion from food resources and the contribution of those resources to the daily diet. This relationship was true for all females at Magod irre-spective of their reproductive condition. This relationship was neither significant for males at the same site nor for both sexes at Bhimashankar. A differential requirement for calcium between the sexes and the occurrence of higher rates of calcium ingestion or the probable presence of more easily digestible calcium at Bhimashankar are postulated to explain the observed phenomenon. Mature leaves and bark appear to be reliable sources of calcium at these sites. 相似文献
97.
Daniel Gygax Henk Nachtegaal Oreste Ghisalba René Lattmann Hans-Peter Schär Christian Wandrey Markus B. Streiff 《Applied microbiology and biotechnology》1990,32(6):621-626
Summary The production of d-ribulose-5-phosphate in an enzyme membrane reactor was examined. Phosphoryl transfer from ATP to d-ribulose was catalysed by d-ribulokinase isolated from Klebsiella pneumoniae. For production of d-ribulose-5-phosphate the phosphoryl donor ATP was used either in stoichiometric or in catalytic amounts. Using catalytic amounts of ATP requires a second enzyme, e.g. pyruvate kinase, to regenerate ATP. The kinetic parameters for d-ribulokinase and pyruvate kinase were determined to calculate the performance of an enzyme membrane reactor for continuous production of d-ribulose-5-phosphate. Both processes operated for more than 200 h. Regardless of whether ATP was used in catalytic or stoichiometric amounts, about the same production parameters were determined. In continuous production space/time yields of 117 g (with ATP regeneration) and 103 g (without ATP regeneration) of d-ribulose-5-phosphate 1–1 per day were reached.Offprint requests to: D. Gygax 相似文献
98.
Combinatorial and synergistic properties of CaMV 35S enhancer subdomains. 总被引:21,自引:2,他引:19 下载免费PDF全文
We have analyzed expression conferred by five subdomains of the cauliflower mosaic virus (CaMV) 35S enhancer in mature transgenic plants. Expression was detected from subdomains that gave no expression at earlier stages of development indicating developmental regulation of expression and confirming the modular organization of the enhancer. In several cases the expression patterns are highly restricted in cell type, providing useful markers for developmental studies. Comparison of expression patterns conferred by various combinations of 35S enhancer cis-elements suggests that synergistic interactions among cis-elements may play an important role in defining tissue-specific expression. This has implications for the nature of a cis-element combinatorial code that could define expression throughout development. 相似文献
99.
本文报道分布于昆明地区的黄臀鹎Pycnonotus xanthorrhous在禁食和四季夜间能量物质——脂肪、蛋白质和糖的消耗情况。结果表明,在人为禁食条件下黄臀鹎的存活时间仅19小时,死亡时躯脂降低79%,去脂飞翔肌干重降低46%,肝糖降低96%。在夜间黄臀鹎消耗大量的储存脂肪,并以冬季的消耗量最大。肝糖提供的能量极少。在繁殖期和换羽期,储存的飞翔肌蛋白质在夜间大量分解以提供鸟体的需要。 相似文献
100.
黄连木五倍子的生态研究与利用 总被引:1,自引:0,他引:1
一、产地自然概况黄连木五倍子最早发现于河南省南部信阳市郊贤山脚下(东经114°0′,,北纬32°10′)。该地为低山丘陵,海拔90一320m,南部紧连鸡公山厂傍依南湾水库和狮河。 相似文献