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1.
GFP标记在转基因青鳉同系繁殖纯化中的应用   总被引:4,自引:0,他引:4  
龙华  木下政人 《遗传》2003,25(4):409-413
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2.
鸡囊胚细胞嵌合体制作技术研究及其应用前景   总被引:1,自引:1,他引:1  
家鸡X期囊胚细胞(BCs)嵌合体技术,既是利用转基因技术进行家鸡品种改良和凭借转基因家鸡生物反应器生产医用蛋白等研究领域的关键技术,也是利用BCs冻存家鸡和珍稀鸟类双亲种质资源实现鸟类品种资源多样性保护、利用和挽救珍稀濒危鸟类的重要途径。从家鸡BCs嵌合体制作技术的基本过程:(1) 羽色嵌合体家鸡模型的建立;(2) 囊胚的分离与消化;(3) 受体种蛋的致弱处理;(4) 受体种蛋的开窗(包括部位、方法及封口技术等);(5) 供体细胞导入受体胚(显微注射或简易操作);(6) 孵化(常规方法或换壳培养)等几个方面的研究进展、目前存在的问题以及研究方向等进行了系统阐述。Abstract: The technology of producing chicken chimeras using blastodermal cells is very important not only in the field of transgenic chicken bioreactor but also in searching for efficient ways to conserve avian genetic resource. The basic processes for producing chicken chimeras consist of: (1) Setting up the color model; (2) Separating and dissociating of donor embryos; (3) Compromising of the recipient embryos; (4) Windowing and recovering the recipient eggs; (5) Cells injecting; (6) Method of hatching. The progress, obstacles and prospects of producing chicken chimeras via BCs were discussed in this paper.  相似文献   

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肖艳萍  奚鹰  黄文英  黄英 《遗传》2002,24(3):232-236
应用荧光原位杂交(FISH)技术检测两个转基因小鼠家系从F1到F4代的整合情况。阳性转基因小鼠98%~100%的中期分裂相,85%~94%的间期核出现杂交信号;阴性对照小鼠100%的中期分裂相、95%~96%的间期核未出现杂交信号。结果表明,该FISH实验条件能对转基因整合位点进行高效特异检测。本文分析的两家系转基因小鼠均为单位点整合, 但整合位点不同。各家系内F1到F4代的转基因小鼠均可检出整合染色体,且整合位点相同,表明外源基因稳定整合并遗传给后代。 Abstract:Fluorescence in situ hybridization (FISH) was used to detect the integration of hFⅨ on chromosomes of transgenic mice from F1 to F4 generation in two strains.For transgenic mice,98%~100% of metaphases and 85%~94% of interphases showed hybridization signal.For negative control mice,100% of metaphases and 95%~96% of interphases showed no hybridization signal.The results demonstrated that FISH developed to detect the integration sites of hFⅨ was high efficient and specific.The integration sites of the transgenic mice analyzed were both single but different between the two strains.The integration chromosomes can be found in the transgenic mice from F1 to F4 generation and the integration sites were the same as each of the strains,which indicated that the transgene was stably integrated and transmitted to offspring.  相似文献   

5.
唐荣华  张君诚  庄伟建  吴为人 《遗传》2003,25(5):620-622
本文综述了拟南芥SUPERMAN基因表观突变体clark kent(clk)的表型、基因型、DNA甲基化及表观突变机制等方面的研究进展。主要研究结果有:clk是SUPERMAN(SUP)的等位基因,能遗传但不稳定,其对称位点(CpG和CPXPG)和非对称位点的胞嘧啶高度甲基化,伴随着SUP转录水平的下降;CpG和CPXPG胞嘧啶甲基转移酶分别是METHYLTRANSFERASE1(MET1)和受KRYPTONITE基因调控的CHROMOMETHYLASE3 (CMT3)。 Abstract:The SUPERMAN gene in Arabidopsis has its epigenetic mutants (the clark kent alleles,clk). The phenotype of clk and its genotype and methylated patterns and the epi-mutation mechanisms of SUPERMAN were summarized in the review. Heritable but unstable sup epi-alleles are associated with nearly identical patterns of excess cytosine methylation within the SUP gene and a decreased level of SUP RNA. The methylation of cytosine at CpG and CPXPG is controlled by METHYLTRANSFERASE1(MET1)and CHROMOMETHYLASE3 (CMT3) which is regulated by KRYPTONITE gene,respectively.  相似文献   

6.
The photorespiratory enzyme L-serine:glyoxylate amino- transferase (SGAT; EC 2.6.1.45) was purified from Arabidopsis thaliana leaves. The f'mal enzyme was approximately 80 % pure as revealed by sodium dodecyl sulfatepolyacrylamide gel electrophoresis with silver staining. The identity of the enzyme was confirmed by LC/MS/MS analysis. The molecular mass estimated by gel filtration chromato- graphy on Sephadex G-150 under non-denaturing conditions, mass spectrometry (matrix-assisted laser desorption/ ionization/time of flight technique) and sodium dodecyl sulfate-polyacrylamide gel electrophoresis was 82.4 kDa, 42.0 kDa, and 39.8 kDa, respectively, indicating dimer as the active form. The optimum pH value was 9.2. The enzyme activity was inhibited by aminooxyacetate and β-chloro-L-alanine both compounds reacting with the carbonyl group of pyridoxal phosphate. The enzyme's transaminating activity with L-alanine and glyoxylate as substrates was approximately 55 % of that observed with L-serine and glyoxylate. The lower Kmvalue (1.25 mM) for L-alanine, compared with that of other plant SGATs, and the kcat/Km(Ala) ratio being approxi- mately 2-fold higher than kcat/Km(Ser) suggested that, during photorespiration, Ala and Ser are used by Arabidopsis SGAT with equal efficiency as amino group donors for glyoxylate. The equilibrium constant (Keq), derived from the Haldane relation, for the transamination reaction between L-serine and glyoxylate with the formation of hydroxypyruvate and glycine was 79.1, strongly favoring glycine synthesis. However, it was accompanied by a low Km value of 2.83 mM for glycine. A comparison of some kinetic properties of the studied enzymes with the recombinant Arabidopsis SGATs previously obtained revealed substantial differences. The ratio of the velocity of the transamination reaction with L-alanine and glyoxylate as substrates versus that with L-serine and glyoxylate was 1:1.8 for the native enzyme, whereas it was 1:7 for the recombinant SGAT. Native SGAT showed a much lower Km value for L-alanine compared to the recombinant enzyme.  相似文献   

7.
This paper is concerned with the bionomics and demography of Pediculaster fletchmanni Wicht (Acari: Siteroptidae) under controlled conditions (20 ± l, 22 ± 1 and 25 ± 1℃, 70% ± 5% relative humidity and a photoperiod of 16L : 8D hours). Glass Petri dishes inoculated with Trichoderma sp. mycelia were used as substrate and food source. The mean developmental time of the egg and the active larva did not differ significantly at the various constant temperatures, but these periods were significantly different for the quiescent larval stage. The preoviposition period ranged from 2.3 to 2.8 days, the ovipositional period increased with temperature increase, and all females died immediately after oviposition. The development of active larvae was the fastest of all life stages. The developmental threshold ranged between 5.25-14.22℃ the highest value being observed for the quiescent larval development. For immature development required 89.29 degree-days. Values of rm (intrinsic rate of increase) were 0.229, 0.398 and 0.386 for 20, 22 and 25℃ respectively. Finite rates of increase (λ) increased along with increasing temperature from 20-25℃ consequently the population doubling time (D) and mean generation time (T) showed significant differences with increasing temperature.  相似文献   

8.
The complete nucleotide sequence of the mitochondrial genome (mitogenome) of Geisha distinctissima (Hemiptera: Flatidae) has been determined in this study. The genome is a circular molecule of 15,971 bp with a total A+T content of 75.1%. The gene content, order, and structure are consistent with the Drosophila yakuba genome structure and the hypothesized ancestral arthro- pod genome arrangement. All 13 protein-coding genes are observed to have a putative, inframe ATR methionine or ATT isoleucine codons as start signals. Canonical TAA and TAG termination codons are found in nine protein-coding genes, and the remaining four (cox1, atp6, cox3, and nad4) have incomplete termination codons. The anticodons of all transfer RNA (tRNAs) are identical to those observed in D. yakuba and Philaenus spumarius, and can be folded in the form of a typical clover-leaf structure except for tRNASer(AGN). The major non-coding region (the A + T-rich region or putative control region) between the small ribosomal subunit and the tRNAne gene includes two sets of repeat regions. The first repeat region consists of a direct 152-bp repetitive unit located near the srRNA gene end, and the second repeat region is composed of a direct repeat unit of 19 bp located toward tRNAIle gene. Comparisons of gene variability across the order suggest that the gene content and arrangement of G. distinctissima mitogenome are similar to other hemipteran insects.  相似文献   

9.
The phylogenetic origin of Beckmannia remains unknown. The genus has been placed within the Chlorideae, Aveneae (Agrostideae), Poeae, or treated as an isolate lineage, Beckmanniinae. In the present study, we used nuclear internal transcribed spacer (ITS) and chloroplast trnL-F sequences to examine the phylogenetic relationship between Beckmannia and those genera that have assumed to be related. On the basis of the results of our studies, the following conclusions could be drawn: (i) Beckmannia and Alopecurus are sister groups with high support; and (ii) Beckmannia and Alopecurus are nested in the Poeae clade with high support. The results of our analysis suggest that Beckmannia should be placed in Poeae.  相似文献   

10.
The ethanol extract of the stem bark of Fraxinus chinensis Roxb. showed good inhibitory bioactivity against VEGF receptor-1 kinase (IC50:13.8 μg/mL). In order to find new and bioactive compounds, the chemical constituents of the stem bark of F. chinensis were investigated and two new coumarins, namely 6'-O-sinapinoyl esculin (compound 1) and 6'-O-vanillyl esculin (compound 2), together with eleven known compounds (compounds 3-13) were isolated. The structures of the two new compounds were identified by their physicochemical properties and spectral analysis, particularly one- and two-dimensional nuclear magnetic resonance spectral methods. The known compound, oleuropein (compound 11), exhibited moderate activity (IC50:(8.7 ± 1.3) μmol/L) to inhibit VEGF receptor- 1 kinase.  相似文献   

11.
A new polynitro cage compound 2, 4, 6, 8, 10, 12, 13, 14, 15-nonanitro-2, 4, 6, 8, 10, 12, 13, 14, 15-nonaazaheptcyclo [5.5.1.1(3,11).1(5,9)] pentadecane (NNNAHP) was designed in the present work. Its molecular structure was optimized at the B3LYP/6-31 G(d,p) level of density functional theory (DFT) and crystal structure was predicted using the Compass and Dreiding force fields and refined by DFT GGA-RPBE method. The obtained crystal structure of NNNAHP belongs to the P-1 space group and the lattice parameters are a = 9.99 ?, b = 10.78 ?, c = 9.99 ?, α = 90.01°, β = 120.01°, γ = 90.00°, and Z = 2, respectively. Based on the optimized crystal structure, the band gap, density of state, thermodynamic properties, infrared spectrum, strain energy, detonation characteristics, and thermal stability were predicted. Calculation results show that NNNAHP has detonation properties close to those of CL-20 and is a high energy density compound with moderate stability.  相似文献   

12.
Summary Concentration of N, P, K, Ca, Mg and S in summer groundnut crop was higher than in kharif while Zn, Fe, Mn and Cu contents were higher in summer crop. Kernel's N, P and Zn; Leaflet's Ca and Mn; Stem's K and Fe; Root's S and Cu and Petiole's Mg contents were highest. Shell's N, P, K, Mg, S, Zn and Cu; Kernel's Ca, Fe and Mn contents were the least. N, P, K, S, Zn and Cu concentrations decreased linearly as the crop grew. Ca, Mg, Fe and Mn concentrations did not display any distinct pattern. Ca concentration was positively correlated with pod yield in both the seasons.  相似文献   

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14.
The goal of this article was to establish reference ranges of the concentration of trace elements in human serum and to compare these results with those reported by other authors. We describe the sample preparation and measurement conditions that allow the rapid, precise, and accurate determination of Al, As, B, Be, Cd, Co, Cu, Fe, Li, Mn, Mo, Ni, Rb, Se, Sr, and Zn in human serum samples (n=110) by inductively coupled plasma-mass spectrometry (ICP-MS). Accuracy and precision were determined by analyzing three reconstituted reference serum samples by comparison with other methods and by the standard addition procedure. The advantages of the ICP-MS method include short time of analysis of the elements mentioned, low detection limit, high precision, and high accuracy. Disadventages include a high risk of contamination due to the presence of some of the elements of interest in the environment, the relatively delicate sample handling, and the high cost of the equipment.  相似文献   

15.
This report attempts to formulate reference ranges of elemental concentrations for 15 trace elements in selected human tissues and body fluids. A set of samples consisting of whole blood, blood serum, urine, milk, liver, and hair were chosen and considered for 15 elements of biological significance: As, Cd, Co, Cr, Cu, F, Fe, I, Hg, Mn, Mo, Ni, Pb, Se, and Zn. The results represent wholly or partially data received from 40 countries of the global regions of Africa, Asia, Europe, North, South, and Central America, Australia, and New Zealand. This survey, even if qualitative, has been useful in demonstrating certain trends of trace-element scenarios around the world. It is of course recognized that both diet and environment exert a strong influence on the distribution pattern of several elements, such as As, Cd, Mn, Pb, Se, and Zn. A limited comparison of the available information on soil status of different countries reflected some interesting associations for elements, such as Mn and Zn. Importantly, this study revealed that only a few countries were in a position to identify a reasonable amount of data on samples requested for this project. Regretably, for a number of countries, any dependable data for even such essential elements as Cu, Fe, and Zn were not available. In view of the nutritional importance of many elements, the time is ripe for concerted efforts by intergovernmental agencies to initiate investigations or commission task forces/projects to generate reliable reference data for selected global regions, which sadly lack data of any kind at present.  相似文献   

16.
The variation with age of the 18 trace element mass fractions and some histological characteristics of intact prostate glands of 50 subjects aged 0–30 years was investigated by instrumental neutron activation analysis, inductively coupled plasma atomic emission spectrometry, and a quantitative morphometric analysis. Mean values ± standard error of the mean (M ± SΕΜ) for the mass fractions (in milligrams per kilogram wet tissue) of these trace elements in pre-puberty were: Al 28.5 ± 9.0, B 0.40 ± 0.11, Ba 1.48 ± 0.44, Br 10.5 ± 1.5, Ca 241 ± 30, Cl 3,203 ± 278, Cu 3.51 ± 0.89, Fe 33.7 ± 4.1, K 2,364 ± 145, Li 0.020 ± 0.004, Mg 153 ± 23, Mn 0.46 ± 0.06, Na 2,286 ± 130, P 1,391 ± 100, S 1,698 ± 132, Si 62 ± 11, Sr 0.38 ± 0.08, and Zn 27.6 ± 2.3. During puberty and postpuberty, when there is a significant increase in circulating androgens, the mean values were: Al 7.2 ± 1.4, B 0.21 ± 0.05, Ba 0.25 ± 0.06, Br 5.8 ± 1.0, Ca 433 ± 81, Cl 2,314 ± 201, Cu 1.77 ± 0.13, Fe 20.9 ± 1.6, K 2,585 ± 118, Li 0.0088 ± 0.0014, Mg 232 ± 27, Mn 0.34 ± 0.04, Na 1,875 ± 107, P 1,403 ± 98, S 1,673 ± 73, Si 22.2 ± 3.1, Sr 0.22 ± 0.03, and Zn 93.3 ± 8.9. Mean values (M ± SΕΜ) of percent volumes (%) of the stroma, epithelium and lumen in the prostate before puberty were 73.4 ± 2.6, 20.4 ± 1.7, and 4.45 ± 0.94, respectively, versus 46.5 ± 2.5, 38.5 ± 1.9, and 14.9 ± 1.2 during puberty and postpuberty. This work’s results confirm that the Zn mass fraction in prostate tissue is an androgen-dependent parameter. For the first time it has been demonstrated that the glandular lumen is a main pool of Ca, Mg, and Zn accumulation and that the stroma is a main pool of Al, B, Ba, Br, Cl, Cu, Fe, Mn, Na, and Si accumulation in the normal human prostate, for the age range 0–30 years. It was concluded that the Ca, Mg, and Zn binds tightly within the prostatic fluid, because the volume of glandular lumen reflects the volume of prostatic fluid.  相似文献   

17.
The effect of age and gender on major, minor, and trace element contents in the intact rib bone of 80 relatively healthy 15–55-year-old women and men was investigated. Contents or upper limit of contents of 16 chemical elements in the rib bone were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Mean values (M?±?SΕΜ) for the mass fraction of Ba, Ca, Cu, Fe, K, Li, Mg, Na, P, S, Sr, and Zn (milligram per kilogram of dry bone) were as follows: 2.54?±?0.16, 171,400?±?4,050, 1.35?±?0.22, 140?±?11, 1,874?±?71, 0.049?±?0.011, 2,139?±?38, 5,378?±?88, 75,140?±?1,660, 1,881?±?51, 291?±?20, and 92.8?±?1.5, respectively. The upper limits of contents of Al, B, Mn, and V were <7.20, <0.65, <0.36, and <0.03, respectively. Statistically significant tendency for the Ca, Mg, and P content to decrease with age was found in the human rib bone, regardless of gender. The mass fraction of Fe in the male rib bone increases with age. It was shown that higher Ca, Mg, Na, P, and Sr mass fractions as well as lower Fe content were typical of female ribs as compared to those in male ribs.  相似文献   

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《Ibis》1894,36(3):447-460
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20.
Oral cancer is one of the main causes of cancer-related deaths in South-Asian countries. There are very limited treatment options available for oral cancer. Research endeavors focused on discovery and development of novel therapies for oral cancer, is necessary to control the ever rising oral cancer related mortalities. We mined the large pool of compounds from the publicly available compound databases, to identify potential therapeutic compounds for oral cancer. Over 84 million compounds were screened for the possible anti-cancer activity by custom build SVM classifier. The molecular targets of the predicted anti-cancer compounds were mined from reliable sources like experimental bioassays studies associated with the compound, and from protein-compound interaction databases. Therapeutic compounds from DrugBank, and a list of natural anti-cancer compounds derived from literature mining of published studies, were used for building partial least squares regression model. The regression model thus built, was used for the estimation of oral cancer specific weights based on the molecular targets. These weights were used to compute scores for screening the predicted anti-cancer compounds for their potential to treat oral cancer. The list of potential compounds was annotated with corresponding physicochemical properties, cancer specific bioactivity evidences, and literature evidences. In all, 288 compounds with the potential to treat oral cancer were identified in the current study. The majority of the compounds in this list are natural products, which are well-tolerated and have minimal side-effects compared to the synthetic counterparts. Some of the potential therapeutic compounds identified in the current study are resveratrol, nimbolide, lovastatin, bortezomib, vorinostat, berberine, pterostilbene, deguelin, andrographolide, and colchicine.  相似文献   

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