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21.
用同位素标记LZF—1 DNA指纹探针进行人的DNA指纹分析   总被引:2,自引:0,他引:2  
同位素γ-32P-ATP对LZF-1DNA指纹探针作5'末端标记后,检测成都地区人群中84名随机个体的DNA指纹,获得了清晰易辨的具有高度个体特异性的DNA指纹图谱.谱带平均数为17.667条,平均等位基因频率为0.167,探针的鉴别机率为4.862×10-10.表明LZF-1DNA指纹探针完全达到了法医学检验中鉴别个体的目的.  相似文献   
22.
寡核苷酸探针(CAC)5/(GTG)5检测了五指山猪、枫泾猪、枫泾猪与长白山猪杂交子一代的基因指纹图.各个体的可分辨谱带,分布于0.7~21.2kb之间.在约1.3kb处的一条共有谱带,可能是家猪的特征带.  相似文献   
23.
Determinants of male mating success in the red bishop (Euplectes orix)   总被引:4,自引:0,他引:4  
We studied sexual selection in the red bishop, Euplectes orix, a colonial, polygynous weaverbird widely distributed over sub-Saharan Africa. Male reproductive success measured in terms of the number of nests accepted by females and the number of eggs and nestlings in all the nests on a male's territory varied considerably. The standardized variance (variance/mean2) in male reproductive success ranged from 0.505 to 1.737 in different years, indicating a high potential for sexual selection in this species. An analysis of genetic parentage for 432 nestlings by non-radioactive, multilocus DNA fingerprinting confirmed that male reproductive success (number of young sired on the territory) in this species can be reliably estimated by the measures introduced above. In all 4 study years there was a strong positive correlation between male mating success and the total number of nests that males built in their territories. The number of nests built can be partitioned into the number of weeks a male held a territory and his nest-building performance. Both factors exert a significant positive effect on male mating success and in combination explained between 53.3 and 86.3% of the variation in male reproductive success. Male morphological characters were found to be of no importance. Males that established a territory in the following season built more nests and held their territories for longer than males that did not establish a territory in the following season, suggesting that these measures might be indicators of male condition and quality. Male nest-building performance (number of nests built per week) seems to be unrelated to male condition or quality. Received: 8 January 1999 / Received in revised form: 7 June 1999 / Accepted: 13 June 1999  相似文献   
24.
复合指纹识别泥沙来源:潜在泥沙源地的选择   总被引:1,自引:0,他引:1  
复合指纹识别技术应用于泥沙源解析的前提是假设研究者能够确定流域内泥沙的潜在来源类型,并且各泥沙源地所占比例之和为1,对潜在源地预判的不确定性将会对结果产生一定的影响。以南京市九乡河上游流域为例,对不同源地各指纹因子做均值显著性检验,检验各个预判源地能否单独作为潜在泥沙源地,同时对比分析不同沙源地对复合指纹因子判断泥沙来源正确率的影响,定量分析沙源地预判过程中的不足,探讨如何减少沙源地选择对泥沙来源识别的影响。通过对比研究发现,预判的4种泥沙源地被重新调整为农田、林地和道路3种类型。调整后各源地指纹因子差异性明显提高,不同泥沙来源的正确判别率最高达到89.2%,泥沙贡献率从高到低依次为农田(39.9%~87.8%)、林地(0.1%~47.7%)和道路用地(0~25.6%)。  相似文献   
25.
The SALLJEX experiment was held during the summer 2002–2003. It consisted of three-dimensional observation of the atmosphere to study the structure of the low level jet along the eastern slopes of the Andes. Daily precipitation water samples were collected at two stations (Resistencia and Salta) in northern Argentina and isotope content was analyzed. The isotope data were used in conjunction with air parcel trajectories obtained from a 3-D kinematic model (3D-MTC) developed by the University of Sao Paulo, Brazil. Values of deuterium excess were related with air masses of continental origin, whilst low values were associated with air masses with longer oceanic trajectories. Furthermore, although data are scarce, results show that oxygen-18 and deuterium excess in rainwater are related with the occurrence of the low level jet.  相似文献   
26.
两种苯甲酸处理系统细菌群落结构的ARDRA分析   总被引:3,自引:1,他引:2  
利用ARDRA(扩增rDNA限制性分析)的方法对两种驯化条件产生的苯甲酸活性污泥中细菌的群落结构进行了分析。提取污泥样品总DNA以后,利用细菌16SrDNA通用引物进行PCR扩增。结果显示:两种活性污泥分别有20.4%和24.3%的酶切类型是自身特有的,可见在微生物群落结构上差别显著。并且利用这种方法分别检测到了103和107种的微生物类型,而利用传统的纯培养手段则只分别分离到了7种和8种微生物,分别只占ARDRA方法的6.8%和7.5%,充分显示了分子生物学的方法在进行微生物群落结构研究方面所具有的优越性。  相似文献   
27.
同位素方法在大气甲烷研究中的应用   总被引:4,自引:0,他引:4  
通过对大气甲烷研究的同位素方法理论基础及其研究进展的综述,概括介绍了现有的大气甲烷同位素研究方法和所取得的成果,讨论分析了在中国开展该项研究的意义和前景。  相似文献   
28.
The degradation products of polymers are identifiable by chromatography. The degradation product patterns (or fingerprints) formed depend on the type of polymer, the degradation mechanism(s), and also the type of additive present in the material. The chromatographic fingerprint of biotically aged degradable low-density polyethylene (i.e., LDPE+starch+prooxidant) shows, in particular, the absence of low molecular weight carboxylic acids, which suggests an assimilation of these carboxylic acids by the microorganisms. The degradation products of natural polymers are usually intermediates that are used again in the anabolic cycles. It is possible to transfer the terminology from the natural polymers, where the catabolism of natural polymers consists of three stages, and apply this also to the degradable synthetic polymers. During stage I the natural polymers degrade to their major building blocks (e.g., amino acids, glycerol, hexoses, pentoses, etc.), during stage II these products are collected and converted to a smaller number of even simpler molecules [e.g., acetyl-coenzyme A (CoA)]. In stage III, finally, the acetyl-CoA enters the citric acid cycle, where energy is gained in parallel with the release of CO2 and H2O.Presented at the international workshop,Polymers from Renewable Resources and their Degradation, Stockholm, Sweden, November 10–11, 1994.  相似文献   
29.
寡核苷酸探针LZF-I进行两栖类DNA指纹分析的初步研究   总被引:2,自引:0,他引:2  
利用寡核苷酸探针LZF-I对两栖类的3属8种28只个体的冷冻和甲醛固定的肝组织作了检测.所获DNA指纹图在个体、种和属间具有特异性.表明该探针进行DNA指纹检测可为两栖动物种、属分类提供依据.  相似文献   
30.
佛坪三官庙地区大熊猫种群数量的DNA指纹分析   总被引:5,自引:0,他引:5  
应用同位素标记大熊猫基因指纹探针F2ZGP96060801,以秦岭南坡中段佛坪国家级大熊猫自然保护区三官庙范围内采集的大熊猫粪便样品作材料,进行了DNA指纹检测.(1)在相同或不同时间、领域采得的粪便样品,显现出相同或不同的DNA指纹图谱,达到个体认定的目的,进一步表明了大熊猫的尽量新鲜的粪便,可以作为DNA指纹分析材料,进行野生种群数量调查.(2)根据检测21个粪便样品的结果,无误地认定了三官庙地区有13只大熊猫个体.其中有3个家系.(3)大熊猫粪便样品的DNA指纹图,通过微机识别的个体数,准确可靠,能获得大熊猫在野外的真实个体数量.  相似文献   
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