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101.
S. G. Tan J. S. F. Barker O. S. Selvaraj T. K. Mukherjee Y. F. Wong 《Biochemical genetics》1993,31(5-6):223-230
We have developed the methodologies for typing and family studies to establish the modes of inheritance of water buffalo red cell acid phosphatase (Acp), protease inhibitor (Pi), and group-specific component (Gc) on isoelectric focusing and albumin (Alb), red cell -esterase-3 (Est-3), and catalase (Cat) on polyacrylamide gel electrophoresis. Family studies showed that Pi, Gc, Alb, and Cat are coded by autosomal genes with two codominant alleles, while Est-3 is autosomal with two codominant alleles and a recessive null allele and Acp exhibits three codominant alleles.This project was funded by the Australian Centre for International Agricultural Research through Grant PN 8364 and the Malaysian programme for Intensification of Research in Priority Areas through Grant IRPA 1-07-05-057. 相似文献
102.
激光辐照选育的435与1002早籼新晶系比湘早籼7号早热,高产,米质好。醋酶同工酶多2—3条带,酶活性增强,增产潜力大。 相似文献
103.
本文用高浓度的G418(800μg/ml)和低浓度的G418(200μg/ml)对包装细胞PLXSN/IL-2/PA317细胞进行40天的选择筛选培养,使其细胞呈稳定状态生长时,收集上清液转染NIH/3T3细胞,进行病毒滴度测定。试图在高选择标记的情况下筛选出高表达目的基因的包装细胞。实验结果表明:高、低浓度的G418对PLXSN/IL-2/PA317包装细胞的选择作用相同,即包装细胞的病毒滴度同选择标记物浓度无关。提示可用低浓度的G418来维持包装细胞的生命。 相似文献
104.
AxenicTrentepohlia odorata was cultured at three different NH4Cl levels (3.5 × 10–2, 3.5 × 10–3, 3.5 × 10–4 M) and three different light intensities (48, 76, 122 µmol m–2 s–1). Chloride had no effect on growth over this range of concentration. High light intensity and high NH4Cl concentration enhanced the specific growth rate. The carotenoid content increased under a combination of high light intensity and low N concentration. WhenD. bardawil was exposed to the same combination of growth conditions, there was an increase in its carotenoid content. The light saturation and the light inhibition constants (K
s andK
i, respectively) for growth, and the saturation constant (K
m) for NH4Cl were determined. TheK
s andK
i values were higher inT. odorata (66.7 and> 122 mol m–2 s–1, respectively) than inD. bardawil (5.1 and 14.7 µmol m–2 s–1, respectively). TheK
m value determined at 122 µmol m–2 s–1, however, was lower inT. odorata (0.048 µM) than inD. bardawil (0.062 µM).Author for correspondence 相似文献
105.
从手术切除的24例女性和12例男性尖锐湿疣新鲜标本中,以及42例女性尖锐湿疣、16例男性外耳道乳头状瘤和4例女性假性湿疣的石蜡包埋标本中,提取组织的基因组DNA,用人工合成的人乳头瘤病毒6.11和16型E6区特异性寡聚核苷酸引物,通过PCR进行HPV DNA的分型检测。结果66例女性尖锐湿疣中,感染HPV6型者4例,感染11型者12例,6+11型混合感染者49例;阴性1例,总检出率达98.4%。4例女性假性湿疣中1例为HPV6型感染,阳性率25%。16例男性外耳道乳头状瘤中HPV6+11型感染者5例,6+16型感染者3例,6+11+16型多重感染者8例,阳性率100%。12例男性尖锐湿疣中,HPV11型感染者7例,6+11型4例,阴性1例,总阳性率91.6%。还对细胞学上空泡化和非典型空泡化尖锐湿疣标本的HPV感染做了比较,未发现差异。 相似文献
106.
核型似近系数的聚类分析方法 总被引:14,自引:0,他引:14
本文根据近年来核型分析所积累的大量资料,以及谭远德(1991)提出的似近分析理论,提出了核型似近系数A聚类分析方法,确定了核型计算公式,井应用于lo种淡水鱼核型似近系数聚类分析,获得了与形态分类学非常一致的结果。此外,还提出了染色体带型计算公式,从而使核型公式和校型似近系数从核型的整体结构、染色体形态结构和染色体内部结构等三个层次上,较精确地刻画了物种核型特性和物种间校型的等同性或同源性。以此核型似近系数作为分类依据所获得的物种分类结果,能真实地和客观地反映物种的自然分类模式。 相似文献
107.
Xiaofen Tan Yifan Wen Zhijun Han Xuyang Su Jing Peng Feng Chen Yadong Wang Tianming Wang Changzhong Wang Kelong Ma 《化学与生物多样性》2023,20(2):e202200089
108.
Shao-Jun Ling Xiao-Lan Yao Juli Caujapé-Castells Jordi López-Pujol Ke Tan Ming-Xun Ren 《植物分类学报:英文版》2023,61(6):1020-1035
Disjunct distribution is a key issue in biogeography and ecology, but it is often difficult to determine the relative roles of dispersal vs. vicariance in disjunctions. We studied the phylogeographic pattern of the monotypic Conandron ramondioides (Gesneriaceae), which shows Sino-Japanese disjunctions, with ddRAD sequencing based on a comprehensive sampling of 11 populations from mainland China, Taiwan Island, and Japan. We found a very high degree of genetic differentiation among these three regions, with very limited gene flow and a clear Isolation by Distance pattern. Mainland China and Japan clades diverged first from a widespread ancestral population in the middle Miocene, followed by a later divergence between mainland China and Taiwan Island clades in the early Pliocene. Three current groups have survived in various glacial refugia during the Last Glacial Maximum, and experienced contraction and/or bottlenecks since their divergence during Quaternary glacial cycles, with strong niche divergence between mainland China + Japan and Taiwan Island ranges. Thus, we verified a predominant role of vicariance in the current disjunction of the monotypic genus Conandron. The sharp phylogenetic separation, ecological niche divergence among these three groups, and the great number of private alleles in all populations sampled indicated a considerable time of independent evolution, and suggests the need for a taxonomic survey to detect potentially overlooked taxa. 相似文献
109.
Tan Kah-Siew; Hoson Takayuki; Masuda Yoshio; Kamisaka Seiichiro 《Plant & cell physiology》1992,33(2):103-108
Irradiation of white fluorescent light (5 W m2) inhibitedthe growth of Oryza coleoptiles. Light irradiation increasedstress-relaxation parameters of coleoptile cell walls, minimumstressrelaxationtime and relaxation rate, and decreased cellwall extensibility (strain/load). Under light conditions, thecontents of ferulic and diferulic acids ester-linked to thehemicellulosic arabinose residue in cell walls increased andcorrelated with the modification of the cell wall mechanicalproperties. These results suggest that light irradiation enhancesthe formation of diferulic acid bridges in hemicelluloses, makingcell walls mechanically rigid and thus inhibits cell elongationin rice coleoptiles. Also, irrespective of coleoptile age orthe presence of light, the ratio of diferulic acid to ferulicacid was almost constant, suggesting that the rate limitingstep in the formation of diferulic acid bridges in Oryza cellwalls is in the step of feruloylation. (Received September 24, 1991; Accepted December 3, 1991) 相似文献
110.
Production of 6-Phenylacetylene Picolinic Acid from Diphenylacetylene by a Toluene-Degrading Acinetobacter Strain
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Jim C. Spain Shirley F. Nishino Bernard Witholt Loon-Seng Tan Wouter A. Duetz 《Applied microbiology》2003,69(7):4037-4042
Several strategies for using enzymes to catalyze reactions leading to the synthesis of relatively simple substituted picolinic acids have been described. The goal of the work described here was to synthesize a more complex molecule, 6-phenylacetylene picolinic acid [6-(2-phenylethynyl)pyridine-2-carboxylic acid], for use as a potential endcapping agent for aerospace polymers. We screened 139 toluene-degrading strains that use a variety of catabolic pathways for the ability to catalyze oxidative transformation of diphenylacetylene. Acinetobacter sp. strain F4 catalyzed the overall conversion of diphenylacetylene to a yellow metabolite, which was identified as a putative meta ring fission product (2-hydroxy-8-phenyl-6-oxoocta-2,4-dien-7-ynoic acid [RFP]). The activity could be sustained by addition of toluene at a flow rate determined empirically so that the transformations were sustained in spite of the fact that toluene is a competitive inhibitor of the enzymes. The overall rate of transformation was limited by the instability of RFP. The RFP was chemically converted to 6-phenylacetylene picolinic acid by treatment with ammonium hydroxide. The results show the potential for using the normal growth substrate to provide energy and to maintain induction of the enzymes involved in biotransformation during preliminary stages of biocatalyst development. 相似文献