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11.
长江流域水牛血液蛋白多态性研究   总被引:11,自引:1,他引:11  
采集长江流域德昌、涪陵、江汉、滨湖和海子5个水牛地方品种共416 头牛的血样。电泳检测血红蛋白、血清运铁蛋白多态性,估算各等位基因频率及基因型频率,根据Hb及Tf两个位点的基因频率进行聚类分析。结果表明,5个水牛地方品种间遗传变异较小,其亲缘关系较近。  相似文献   
12.
为将荧光原位杂交技术应用于基因定位研究中,探讨一种能有效地检测转基因动物染色体上外源基因整合状态的实验方法,对小鼠腹腔注射秋水仙素后,取转基因小鼠骨髓制备中期染色体,将传统的FISH方法加以改进,检测外源基因在转基因小鼠染色体上的整合状态.检测结果表明,外源人βE珠蛋白基因已稳定地整合于小鼠染色体上.FISH能直观地反映外源基因在转基因动物染色体上的整合状态,该方法可对转基因动物及基因转移研究中的外源基因整合后进行染色体定位检测。 Abstract:To determine the integration site of human βE globin gene in the chromosomes of transgenic mice, transgenic mice carrying human βE globin gene were injected intraperitoneally with colchicines, then, bone marrow cells wereisolated and metaphase chromosomes were prepared, the traditional FISH method was improved to detect the integration site of humanβE globin gene in transgenic mice when combined with G-banding. Human t3E globin gene can bedetected in different position of different chromosomes in transgenic mice and FISH signals showed that two mice were heterozygous of human 13E globin gene and one was homozygous. Human t3E globin gene was integrated into thechromosomes of transgenic mice in a random pattern and the results demonstrated that FISH can be used to investigate the integration site of foreign genes in transgenic mice.  相似文献   
13.
董兆文  崔应琦 《遗传》1992,14(2):40-40
新生儿出生缺陷已成为影响人口素质的重要因素。在引起出生缺陷的诸因素中,宫内病毒感染是一个重要原因。风疹病毒等对胎儿的影响早巳为人们所熟悉,而巨细胞病毒(cytomegalovirus,CMV)对胎儿的危害,近年来已受到人们的重视。据国内外调查,在新生儿中先天性CMV感染的发生率在0.5—2.0%之间。目前对先天性CMV感染的研究主要用新生儿尿样和脐带血作为研究材料。从产前诊断的角度考虑,  相似文献   
14.
An investigation of gamasid mites on the body surface of small mammals was carried out in Yunnan Province of China from 1990 to 2004. The small mammal hosts were captured from 25 counties which represent five geographical subregions, namely Middle Subregion of Hengduan Mountains, Southern Subregion of Hengduan Mountains, Eastern Plateau Subregion of Yunnan, Western Plateau Subregion of Yunnan and Southern Moun- tainous Subregion of Yunnan. The captured 10 803 small mammal hosts belong to nine families, 29 genera and 52 species in four orders (Rodentia, Insectivora, Scandentia and Lagomorpha). A total of 68 571 gamasid mites were collected from the body surface of the captured small mammal hosts and all the gamasid mites were identified to 10 families, 33 genera and 112 species. This paper lists all the mite species, together with their taxonomic position (genera and families) and their corresponding hosts. Much more mite species were found in the Middle Subregion of Hengduan Mountains than in other geographical subregions. The total individuals of mites and small mammals in the Middle Subregion of Hengduan Mountains are also the most plentiful in the five geographical subregions. Three dominant mite species and three dominant small mammal hosts were determined as the dominant species in the investigated areas of Yunnan Province. The dominant hosts are Rattus flavipectus (which accounts for 34.85% of the total individuals), Apodemus chevrieri (13.43%) and Rattus norvegicus (10.40%) while the dominant gamasid mite species are Laelaps nuttalli (Hirst, 1915) (27.84%), Laelaps echidninus (Berlese, 1887) (18.38%) and Laelaps guizhouensis (Gu et Wang, 1981) (14.79%). The results showed the high species diversity of gamasid mites in Yunnan Province and the uneven distribution feature in different subregions.  相似文献   
15.
As an immediate-early protein of herpes simplex virus, infected-cell polypeptide 0 (ICP0) exhibits complicated interactions with host cells, and its regulatory function on gene expression is of great importance. Since the ICP0 encoding sequence contains many rare codons which are absent in E.coli, and ICP0 is highly unstable in prokaryotic cells, expression of entire ICP0 in prokaryotic cells has never been reported. In order to further investigate the function of ICP0, a recombinant plasmid was constructed by subcloning a cDNA fragment encoding an amino-terminal of 105 residues of the ICP0 protein into pGEX-5x-1 vector. The resulting GST-105 fusion antigen peptide was expressed with high efficiency in E.coli. Antibodies prepared after the immunization of mice with purified fusion protein can recognize not only the denatured ICPO protein, but also the native ICPO protein with normal biological conformation.  相似文献   
16.
The roots of Anemone altaica Fisch. ex C. A. Mey. have been used in the treatment of epilepsia, neurasthenia, and arthritis in Chinese folk medicine for a long time. In order to find new and bioactive compounds, the chemical constituents of the roots of A. altaica were investigated and nine compounds were isolated from the EtOH extract of this plant. On the basis of spectroscopic methods, the structures of these compounds were elucidated as 4-(9H-β-carbolin- 1-yl)-4-oxo-butyric acid (1), carboxymethyl isoferulate (2), isoferulic acid (3), cirsiumaldehyde (4), 5-hydroxy-4-oxo-pentanoic acid (5), triacontane (6), palmic acid (7), β-sitosterol (8), and daucosterol (9). Among them, 1 and 2 were new compounds, and 3 and 4 were obtained from this genus for the first time.  相似文献   
17.
Scientists and policy-makers are now well aware of the ecological and societal problems associated with the introduction of species by humans across natural barriers to dispersal. Some introduced species spread abundantly in their new habitats and have negative effects on existing species, both agricultural and natural. Such introduced,invasive species can alter fire, nutrient, and hydrological regimes and have large economic costs.  相似文献   
18.
利用早孕绒毛组织和PCR技术检测先天性人巨细胞病毒感染   总被引:1,自引:0,他引:1  
人的巨细胞病毒(Human cytomegalovirus,HCMV)已成为引起宫内感染的重要原因。在新生儿中先天性HCMV的感染率为0.2-2.2%。为了建立一种可行的先天性HCMV感染产前诊断技术,我们利用早孕绒毛组织和聚合酶链反应(Polymerase chain reaction,PCR)技术对孕早期的先天性HCMV感染进行了研究。现简报如下:  相似文献   
19.
In the 1980s some special protozoa were gradually recognized: being eukaryotes, they possess some characteristics between prokaryotes and eukaryotes, for example, lack of eukaryotic organelle such as mi-tochondria, and even 70S ribosomes in some species, containing 16S, 23S rRNA like those of prokaryotes. These protozoa contain diplomonads (e.g. intestinal parasite Giardia), parabasalids (e.g. venereal disease pathogen Trichomonas), microsporidia (e.g. the human pathogen Encephalitozoon), a…  相似文献   
20.
中、上石炭统在四川省境内分布范围较窄,除涪陵一带可能有中石炭统沉积外,只在西北部龙门山一带及松潘区(?)有零星出露。其中以江油马角坝附近发育比较完整,产化石较丰富。1961年,我所川北地层队在江油县马角坝附近张坝沟一个采石场测得中、上石炭统剖面一个,采集了(竹蜓)类及珊瑚类化石若干。剖面的层序自上而下为:  相似文献   
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