色变银环蛇与正常银环蛇的形态学及毒性比较研究

目的研究色变银环蛇与正常银环蛇的形态学差异。方法比较蛇外形、鳞片、毒腺、排毒量、毒性等情况。结果色变银环蛇与正常银环蛇的鳞片数目无异,但其毒腺大小、排毒量、毒性均有明显差异。结论可能由于蛇的生存环境发生了改变,故而出现了银环蛇的形态改变。     

Photography in limnology: documentation of lake color using a CCD camera

During a survey of Norwegian lakes, photographic records were made of lake color as reflected by a white Secchi disk positioned at half of the depth of extinction. The pictorial distinction between different lakes is documented in this article. The pictures recorded can readily be transferred to a color model [e.g., Commission Internationale de L’Éclairage (CIE)-Lab]; from there, numerical color parameter values such as hue (h*, the quality of color) and chroma (C*, the intensity of color) may be assigned to each record. There are, however, limitations and obstacles connected with the transformation of color values recorded by a CCD camera (or film digitizers) to absolute numerical values comparable between different cameras and systems. A single CCD camera may be useful for documenting lake color, but there are technical limitations restricting its use as a scientific instrument for quantitative purposes.     

Spectral Test Instrument for Color Vision Measurement

Common displays such as CRT or LCD screens have hmlted capabilities in displaying most color spectra correctly. The main disadvantage of these devices is that they work with three primaries and the colors displayed are the mixture of these three colours. Consequently these devices can be confusing in testing human color identification, because the spectral distribution of the colors displayed is the combined spectrum of the three primaries. We have developed a new instrument for spectrally correct color vision measurement. This instrument uses light emitting diodes (LEDs) and is capable of producing all spectra of perceivable colors, thus with appropriate test methods this instrument can be a reliable and useful tool in testing human color vision and in verifying color vision correction.     

彩色多普勒超声对无水酒精治疗肝细胞癌早期疗效的评价

目的:探讨彩色多普勒超声评价无水酒精治疗肝细胞癌早期疗效的临床应用价值。方法:利用彩色多普勒血流显像(CDFI)、彩色多普勒能量图(CDE)检查技术,经皮无水酒精瘤内注射(PEI)治疗52例肝细胞癌(肿块直径1.65.0cm),疗程结束后一周,以CDFI及CDE血流显示的有无作为评价PEI早期疗效的观察指标,并行组织学活检病理检查。结果:52个肿块经PEI治疗后,CDFI及CDE示大部分肿块血流信号消失,小部分肿块能检出血流信号,但较治疗前明显减少。以病理检查结果为金标准,CDFI及CDE评价PEI治疗后肿瘤的灭活情况,其敏感性为:50.0%、77.8%,准确性为78.8%、90.4%,Kappa值为:0.486、0.779。结论:CDFI、CDE动态监控PEI治疗过程对指导治疗意义重大,CDFI、CDE评价PEI结果客观、可靠,CDE可以敏感而直观地显示PEI治疗后肿瘤周边及内部残存的血流信号,对指导PEI治疗、时机及靶目标的选择以提高疗效具有重要的临床应用价值。     

理化因子导致梅花'南京红'花色色素的颜色变化

梅花是中国的候选国花之一。属于花色苷的梅花'南京红'花色色素用含1％浓盐酸(v／v)的甲醇提取,并呈现纯净的紫红色。体外试验表明:该色素在pH0-3范围内颜色稳定,因不同光质、热、氧化剂、还原剂、螯合剂而呈现无色、墨绿色或黄绿色,因不同金属离子、离子的不同浓度而呈现程度不同的红色、紫色、黑黄色、红中带黑或微蓝绿色,葡萄糖和低浓度苯甲酸钠几乎不影响其色泽,蔗糖使颜色变淡,柠檬酸却使其颜色变深。该文可为梅花红色花色的机理探索、梅花花色苷的分子结构鉴定、梅花红色花色色素的开发利用提供参考和前提。     

滤光膜对喜树幼苗叶片生长和喜树碱含量的影响

喜树 (Camptotheca acuminata)为中国特有树种 ,因其次生代谢产物喜树碱具有抗癌作用而闻名。通过用黄色、红色、蓝色 3种滤光膜对温室栽培的喜树幼苗进行遮光处理 ,研究了不同光照环境下喜树幼苗叶片生物量、叶绿素含量、光合作用和喜树碱含量的差异。结果表明在 30 d的遮光过程中 ,红膜和蓝膜遮光明显导致幼苗叶片生物量降低 ,黄膜遮光下幼苗叶片生物量在处理后 2 5 d才表现明显降低。不同滤光膜下幼苗叶片叶绿素含量先降低然后升高 ,遮光幼苗的叶绿素 a/ b明显低于日光幼苗。幼苗日最大净光合速率的顺序是 :日光 >黄膜 >红膜 >蓝膜。处理后第 2 0天 ,不同滤光膜下幼苗的光饱和光合速率 (Amax)、光饱和点 (Is)、光补偿点 (Ic)、最大表观量子效率 (AQYmax)都不同程度的低于日光幼苗。处理后第 10天至第 30天 ,遮光幼苗叶片喜树碱含量均显著高于日光下幼苗 ,以蓝膜下幼苗的喜树碱含量最高。蓝膜和黄膜下幼苗的喜树碱产量在后期处理中显著高于日光下幼苗 ,蓝膜下幼苗喜树碱产量在第 30天最高 ,是日光下幼苗的 2 .4 9倍。红膜下幼苗的喜树碱产量在第 10天后与日光下幼苗差异不显著。通过滤光膜遮光促进喜树碱在幼苗叶片中的积累 ,提高了叶片喜树碱产量 ,对喜树碱的生产实践有一定的意义     

梅花‘南京红’花色色素花色苷的分子结构

经特殊颜色反应、纸层析、紫外 -可见光谱、高效液相色谱、气相色谱和核磁共振波谱分析表明 :梅花‘南京红’花色色素的 3种主要花色苷分别是 :花青素 3 氧 (6″ 氧 α 吡喃型鼠李糖基 β 吡喃型葡萄糖 )苷 ,花青素 3 氧 (6″ 氧 没食子酰 β 吡喃型葡萄糖 )苷和花青素 3 氧 (6″ 氧 反式阿魏酰 β 吡喃型葡萄糖 )苷。花青苷在根本上决定着‘南京红’的粉红色花色 ,并可能强化‘南京红’的耐寒能力 ,也奠定了开发和利用该种花色色素的基础。     

犬MC1R基因T105A基因座多态性及 与毛色性状相关性的研究The

为了检测犬MC1R基因T105A基因座的多态性,并分析该多态性与犬毛色表型的相关性,抽取111只外科手术学实验用杂种犬血液并提取DNA,记录毛色表型。采用PCR-RFLP技术,对MC1R基因T105A基因座进行基因多态性分析,并对该基因座DNA进行克隆测序;用二元变量相关分析的统计学方法分析基因座多态性与毛色性状之间的相关性。经PCR-RFLP分析结果表明,T105A基因座序列具有多态性,表现为A、B二个等位基因和AA、AB及BB 3种基因型。A、B等位基因频率分别为72.97%和27.03%,基因杂合度（H）为0.39。基因型AA频率为55.86%,BB为9.91%,AB为34.23%。对T105A多态性片段DNA克隆测序后发现,MC1R基因在编码第105位氨基酸的密码子第一个碱基存在由G到A的单碱基突变,该突变导致第105位氨基酸发生由丙氨酸向苏氨酸的改变。统计分析结果表明MC1R基因T105A基因座的多态性与毛色性状不存在显著的相关性,这可能是由于外科手术学实验用犬是杂种犬,其遗传背景不同所致,尚须在纯种犬群体中进一步研究MC1R基因对毛色的影响。 Abstract: In order to detect the polymorphism of T105A in MC1R gene in dogs and to analyze the relationship between the genetic polymorphisms and phenotypes of dog coat color, the blood samples of 111 cross-breed dogs were taken and their genomic DNAs were extracted. The phenotypes of dog coat color were recorded. The T105A locus of MC1R gene in the canine was detected through the technology of PCR-RFLP. Furthermore, the polymorphic fragments at T105A were sequenced. The relationships between the polymorphism of T105A and coat color trait were analyzed by the statistical methods of bivarate correlation analysis. By the method of PCR-RFLP, the T105A polymorphism was found with two alleles A and B and three genotypes AA, AB and BB. The frequencies of two alleles were 72.97% and 27.03%, respectively. The heterozygosity of T105A locus was 0.39. The frequencies of three genotypes were 55.86%, 34.23% and 9.91%, respectively. According to the results of sequencing, one base change from G to A at the position 105 was found at T105A locus and it altered amino acid at the position 105 from alanine to threonine. According to the statistical analysis, no significant association between the polymorphism of MC1R gene and the coat color was found and the result may be due to the differences of genetic background. Further research on MC1R gene should be done in pure breed dogs.     

水稻台中65与其花粉不育近等基因系的杂种F1的裂药性研究

以台中65及其7个F1花粉不育近等基因系为材料,对水稻亚种间杂种F1裂药性及其与小穗育性的关系进行了研究。结果表明,杂种F1的裂药性受花粉不育基因互作控制。不同杂合座位内等位花粉不育基因互作导致杂种F1花药不开裂的程度不同,S-b座位导致杂种F1部分花药不开裂;不同杂合座位问非等位花粉不育基因互作明显降低杂种F1的裂药程度;杂种F1中含杂合花粉不育基因座位数越多,其裂药指数越小,裂药程度越低,含三个杂合花粉不育基因座位的杂种F1裂药指数为2．27,35．3％的花药不开裂。杂种F1花药不开裂的原因随其所含的杂合花粉不育基因座位种类和数目不同而异。杂种F1裂药程度的下降显著减少落在其柱头上的花粉总数和萌发的花粉数。杂种F1裂药指数和结实率呈极显著的正相关关系。     

花卉基因工程研究进展Ⅰ：花色

1987年人们首次通过转基因技术获得了改变花色的矮牵牛,使得花卉选育迈入分子时代。其优点在于可有目的的地改变花卉的某一性状而不影响其它性状,并缩短育种周期。目前,与花色基因工程有关调控机理已日益清楚,分离到大量的相关酶和基因,获得了一批转基因花卉。本文重点介绍了国内外花色基因工程的研究进展,同时简单评述了花卉基因工程研究中存在的问题并展望其应用前景。