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1.
广东鼎湖山马尾松年轮元素含量及其相关性研究   总被引:1,自引:0,他引:1  
The concentrations of the elements in the annual rings of Pinus massoniana reflect the influence of both regional factors and species characteristics in absorbing,accumulating and distributing elements.The changes of environmental factors may result in concentration changes of elements in tree rings.Therefore,variations of tree ring element concentration may provide some clue in studying environmental changes.Some of eight elements studied are strongly correlated with others,the reason of which might be their similar structural and enzymatic functions in the plant cell,similar chemical properties and similar or opposite reaction to variations in some environment factors.  相似文献   

2.
2010 has seen rapid progress in stem cell research in China.Not only the major funding agencies had provided extensive funding to stem cell research,the publications by Chinese stem cell biologists also flourished in top-notch scientific journals.In this special review,we highlighted some recent studies that had been published in Science China Life Sciences and Cell Research,two key SCI journals based in China.Not surprisingly,these studies mainly focused on some of the highly pursued stem cell types: embryonic stem cells(ES cells),induced pluripotent stem cells(iPSCs),neural stem cells(NSCs) and mesenchymal stem cells(MSCs).  相似文献   

3.
张宇伟  丁六松  来茂德 《遗传》2003,25(5):601-606
再生基因家族自1988年被发现以来,其在糖尿病、炎症创伤与肿瘤尤其在消化系统肿瘤中的作用日渐被重视。越来越多的该家族成员被发现,并已开始考虑在临床治疗中应用。这些研究开始显示再生基因家族的潜在应用价值。 Abstract:Since the first member of Reg gene was discovered in 1988,it has been verified that Reg genes play important roles in diabetes,inflammation and injury,and tumors.More members were cloned and their application in treatment was studied.With the development of related research,there is a great potential of Reg family in biomedical field.  相似文献   

4.
To study the distribution characteristics of Hepatitis B virus (HBV) genotypes in groups of the Zhuang nationality of Baishe in Guangxi, the PCR sandwich hybridization-ELISA technique was used to determine the genotypes in 30 patinets of Zhuang nationality with hepatitis B. Geontype B, C, D and non A-F were found in this group, in which 56.6% of them were type D,46.6% type C,33.3% typeA-F, 20% type B, Most patients were found with types C D, D B or C B. It is suggested that there are genotypes D, C, B and non A-F in this area, and the major one was genotype D. There are mixture of genotypes C D, B C, D B in this region, so the HBV genotype might be associated with area and nationality.  相似文献   

5.
罗伯逊易位研究的进展   总被引:2,自引:0,他引:2  
本文总结了罗伯逊易位研究的现状、内容和技术方法,并对它在畜牧品种的改良、分子遗传学方面的应用作了探讨,指出了它在研究进化生物学方面的重要意义。 Abstract:Robertsonian translocation is important in the study of evolution biology.Current progress,contents,technology and methods about Robertsonian translocation studies are introduced in the article.The usefulness in improving the breeds of pasturages and molecular genetic aspect are also discussed.  相似文献   

6.
To elucidate the cause of prenatal and early postnatal death in giant panda, pathological studies have been carried out on paraffin-fixed tissue sections from two fetuses and four cubs. The fetuses appeared to have classical atrophic changes in lung and hemorrhage in multiple organs, whereas the cubs showed purulent inflmnmation in various organs, most profound in lung and umbilicus. Localized infusion of bacteria and neutrophils were identified in the focus. Acute enteritis and hepatitis were also observed, as well as purulent encephalitis in one case. Variable degrees of congestion, hemorrhage, denaturalization and putrescence were evident in heart, liver, spleen, kidney, intestines, and lymph nodes. The results indicated that the fetuses died from suffocation whereas the cubs died from infection.  相似文献   

7.
We are greatly encouraged by the enthusiastic discussionssince the publication of our report on Science (vol. 287, no. 5458, p1622-1626, 2000) on the Bose Paleolithic study. These discussions are highly appreciated, as they are positive in promoting the development of Paleolithic science in Chi-na, and in clarifying some issues at Bose. Here, particular thanks are extended to Lin for his comments, which are briefly addressed as follows.
Most of the questions of Lin are centered on the relations of the tektites, stone artifacts and the stratigraphy. These had already been raised in the comments of Koeberl et al (vol.289, no. 5479, p507a, title :Tektites and the Age Paradox in Mid-Pleistocene China) and replied in detail in July 2000 in the same issue. Since then, further investigations have been carried out at Bose and there has not been any new evidence affecting our earlier interpretations, which are also supported by the lack of stone artifacts on the terraces younger than T4. It should be clarified that the stone tools discovered at the upper-most part of T4 at some localities are of Neolithic age, rather than Paleolithic. Thus, the statement of Lin about two possible generations of Paleolithic layers is not supported but should be further studied. Lin questioned in his past publications the existence of handaxe in the Paleolithic of China while typical handaxes in China have been internationally recognized by the majority of the Paleolithic community, such as those from the Dingcun, Lantian and Bose sites. The available ages of the Bose Paleolithic tools are naturally a contradiction to the “Movius line”.
Continuous investigation is being carried out at Bose, which is expected to provide further new ev- idence on the main issues.Discussion in the field would be greatly helpful for clarifying some of these issues. We cordially invite Lin to realize a first visit to Bose, and are looking forward to his contribution.
  相似文献   

8.
鸟类线粒体DNA研究概述   总被引:8,自引:0,他引:8  
陈晓芳  李爽  王黎  袁晓东  汤敏谦  李庆伟 《遗传》2002,24(3):371-375
线粒体DNA作为理想的分子标记已被广泛用于鸟类种群遗传学和进化遗传学的研究,并取得了许多有意义的结果。本文介绍鸟类线粒体DNA的组成、结构特点及多态性的研究,综述近年来有关鸟类分子进化研究的进展情况,对今后的发展进行了初步的探讨。 Abstract:Mitochondrial DNA as a genetic marker has been successfully applied to the study of molecular evolution of birds.The apparently maternal inheritance of mitochondrial DNA and its fast evolution in primary sequence has made it attractive in population and evolutionary genetics.Mitochondrial DNA of birds displays two characteristics not seen in other vertebrates mtDNA,that is,a novel gene order and the absence of an equivalent to the light-strand replication origin.The research on polymorphism of mtDNA can resolve phylogenies of birds both at lower and higher taxonomic levels.Here we review progress on avian molecular evolution in recent years,and make preliminary studies of the development in this field.  相似文献   

9.
Forty different medicinal plants were investigated for arbuscular mycorrhizal association in the Rajshahi University Campus in Bangladesh. The results indicated that 35 different plants were infected by AM (arbuscular mycorrhizal) fungi as found by trypan blue staining procedure. The percentage of root colonization by AM fungi varied from 13.3% to 100%. Mangifera indica and Morus indica have maximum percentage of colonization (100%). The intensity of root colonization were abundant in the plants belonging to the families Anacardiaceae, Asclepiadaceae, Moraceae, Leguminosae and Apocynaceae whereas the intensity of colonization of crop roots were moderate and poor belonging to Gramineae and Leguminosae. The presence of greater number of spore in soil was always associated with the incidence of abundant mycelia. In plant roots the formation of spore and mycelia was restricted by low pH. Number of mycorrhizal fungus spores ranged between 35 to100 per 100g air dried soil in different family respective soils. The frequency of mycorrhizal fungus infection showed positive correlation with soil pH, moisture, water holding capacity, texture, total nitrogen, organic carbon, phosphorus, calcium, potassium, and magnesium. Especially phosphorus and nitrogen in the soil greatly influenced the plant root infection by AM fungi.  相似文献   

10.
方兴未艾的古代DNA的研究   总被引:9,自引:2,他引:7  
蔡胜和  杨焕明 《遗传》2000,22(1):41-46
保留在古代生物遗骸中的遗传物质DNA是一种重要的遗传资源。古代DNA的研究对于了解包括人类在内的各种生物的起源、进化和迁徙有重要意义。古代DNA的研究有其自身的特点,并且已经取得一系列重要成就。本文综述古代DNA研究的历史、方法和进展。 Abstract:DNA present in ancient samples can be recovered,amplified and analysed.It opens a new window for genetic analysis in many different disciplines,such as anthropology,archaeology,human population genetics,animal and plant evolutionary taxonomy and forensic science.In general,ancient DNA is rare in quantity,damaged in quality.To ensure the reproducibility and reliability of the results,great cares should be taken,such as various measurements against contamination and phylogenetic analysis of ancient DNA sequences.In this paper we review recovery,amplification and analysis of ancient DNA,also discuss the guidelines to ensure the authenticity of ancient DNA and the recent advances in ancient DNA study.  相似文献   

11.
Sox基因家族研究的新进展   总被引:20,自引:0,他引:20  
常重杰  杜启艳  邵红伟 《遗传》2002,24(4):470-476
  相似文献   

12.
The genus Buergenerula in driftwoods and culms of Spartina alterniflora in intertidal zone is newly recorded from China seas. Taxonomy and morphology of Buergenerula spartinae and the comparison between the species and similar species were discussed in this paper. The specimens were deposited in Mycology Herbarium at Qingdao Agricultural University (MHQAU).  相似文献   

13.
In the past three decades, many palynologists have contributed to our knowledge of spore-pollen content from Cenozoic sediments of China. However, most of them centered on the Early Tertiary and Quaternary, whereas study on the Late Tertiary palynology in our country was less attractive mostly because of our undue emphasis laid on its value in stratigraphic application and economic interest. As a matter of fact, from an evolutionary standpoint the Neogene palynofloras represent an important phase in Cenozoic floral history, which embrace a number of pioneers of modern plants and exhibit an embryonic framework of modern Iandscape. Moreover, a large collection and painstaking research on the palynofloras will certainly proliferate the applied value in a stratigraphic context. Therefore, the Neogene palynological study should share an equal importance in the investigation on Cenozoic palynofloras.  相似文献   

14.
七种鲅亚科鱼Ag-NORs的比较研究   总被引:2,自引:0,他引:2  
本文研究了红鳍鲅、青稍红鲅、蒙古红鲅、翘嘴红鲅、CAN条、团头鲂和长春鳊等7种鲅亚科鱼类的银染带。结果表明,在中期分裂相中各自的A g-NORs数在4-8个之间。综合分析比较国内已发表的鲤科银染资料,得出多数中国鲤科鱼类的Ag-NORs数为4位于两对sm染色体短臂端部。鲅亚科鱼在进化过程中NORs数目有增加的趋势。 Abstract:The Ag-NORs of 7 species in Abramidinae,namely Culter erythropterus,Erythroculter dabryi,E.ilishaeformis,E.mongolicus,Hemiculter leucisclus,Megalobrama amblycephala and Parabramis pekinensis were studied.The results showed that 4~8 Ag-NORs were observed in their metaphases respectively.Based on the Ag-NORs data of Cyprinid fishes published in China,we suggested that the number of Ag-NORs in major Chinese Cyprinidae is 4,locating on the short arm tips of two pairs smchromosomes.The trend of Ag-NORs number in Abramidinae fishes is towards increasing in course of evolution.  相似文献   

15.
This paper reports the development of the nuclear transplanted eggs obtained by transplanting Xenopus laevis blastomere nuclei to Bufo raddei. The formation of the donor nuclei is similar to that of the male pronuclei in the normal development egg in the early stage while shows degradation in the late stage after transplanting. The chromosome complement formes in some eggs 30 minutes after transplantation, which is assumed to contribute to the development of the transplanted eggs [Acta Zoologica Sinica 51 (5) : 924 - 931, 2005].  相似文献   

16.
17.
本文对203名青少年白发患者的皮纹进行了分析,并与216名正常对照组个体作了比较.发现青少年白发组的As和Wd出现率以及A/A和L/W的对应频率均显著低于正常对照组;青少年白发组女性的a-bTRC值、男性变异型掌褶纹的出现率、10指同斗频率、右手Ⅰ2区及左手Hy区的花纹出现率均显著高于正常对照组的相应出现率.说明青少年白发者的皮纹可能有自身的遗传特征。 Abstract:This paper sought to analyze the dermatoglyph of 203 cases with juvenile poliosis,and make an individual contrast with the control group of 216 normal juveniles.It was found that the incidence of As and Wd in the group of juvenile poliosis and the correspondence rate of A/A and L/W were obviously lower than those of the normal contrast group,while a-b TRC value in the female patients with juvenile poliosis and the incidence of abnormal palmprint in the male, the frequency of all loop whorl,and palm patterns in the I2 area of the right hand and in the Hyarea of the left hand were evidently higher than the corresponding incidences of the normal contrast group.Dermatoglyph of the juvenile poliosis has its own heredity.  相似文献   

18.
猪显性白毛调控基因(KIT)的研究   总被引:15,自引:0,他引:15  
邓素华  黄路生  任军  陈克飞  丁能水 《遗传》2000,22(6):434-436
猪的白毛色性状由显性基因KIT决定。本文从KIT基因的定位、突变分析、分子基础和作用机制等方面综述了对该基因的研究现状,叙述了KIT基因的研究意义。 Abstract:The dominant coat color in pigs is controlled by KIT gene.The current status of KIT gene is expressed in location、mutation、molecular basis and mechanism.Significance of KIT gene is also discussed in this paper.  相似文献   

19.
多波段卫星遥感海洋赤潮水华的方法研究   总被引:7,自引:0,他引:7  
The spectral characteristics of the coastal waters in East China Sea was studied using in situ measurements, andt he multiband algorithms of remote sensing for bloom waters was discussed and developed. Examples of red tide detection using the algorithms in the East China Sea were presented. The results showed that the algorithms could provide information about the location and the area coverage of the red tide events.  相似文献   

20.
人类MINK基因的两种突变导致长QT综合征(LQTS)。我们设计了两对引物利用PCR-SSCP结合直接测序法在病人及健康者中对MINK基因进行分析,结果发现第149位密码子产生A→G转换。在所研究的对象中,此变化在病人及正常对照者中均有存在。提示MINK基因的此突变性质为非病理性的多态突变。 Abstract:Two novel mutations that have been described in human MINKgene are corresponding for Long QT Syndrome (LQTS). Two pairs of primers were designed to screen hMINKgene both in patients and in normal controls, We performed screening by PCR-SSCP analysis combining with direct sequencing. It showed a single A→G transition at position 149. This change was found in both patients and healthy subjects.  相似文献   

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