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Erratum to:Science China Life Sciences,November 2013 Vol.56 No.11:1038–1046doi:10.1007/s11427-013-4560-7The legend of Figure 1 should be as follows:Figure 1 Distribution map of 15 subplots at three types of habitats(ridge,slope and valley) 相似文献
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The thermoacidophilic archaeon Sulfolobus shibatae synthesizes a large amount of the 7-ku DNA binding proteins known as Ssh7. Our hybridization experiments showed that two Ssh7-encoding genes existed in the genome of S. shibatae. These two genes, designated ssh7a and ssh7b, have been cloned, sequenced and expressed in Escherichia coli. The two Ssh7 proteins differ only at three amino acid positions. In addition, the cis-regulatory sequences of the ssh7a and ssh7b genes are highly conserved. These results suggest the presence of a selective pressure to maintain not only the sequence but also the expression of the two genes. We have also found that there are two genes encoding the 7-ku protein in Sulfolobus solfataricus. Based on this and other studies, we suggest that the gene encoding the 7-ku protein underwent duplication before the separation of Sulfolobus species. Binding of native Ssh7 and recombinant (r)Ssh7 to short duplex DNA fragments was analyzed by electrophoretic mobility shift assays. Both native and recombinant forms of the protein behaved in a similar fashion in the assays, suggesting that the interaction of Ssh7 with DNA is not affected either by specific lysine methylation found in the native Ssh7 proteins or by the difference between the two Ssh7 isomers in amino acid sequence. Our data show that Ssh7 binds duplex DNA fragments with a binding size of ~ 6.6 base pairs and an apparent dissociation constant of (0.7—1.0)×10-7 mol/L under the assay conditions employed in the present study. In addition, Ssh7 binds more tightly to negatively supercoiled DNA than to linear or relaxed DNA. : 相似文献
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Shim JH Kim KH Cho YS Choi HS Song EY Myung PK Kang JS Suh SK Park SN Yoon DY 《Amino acids》2008,34(1):135-141
Summary. In a previous study, we established a stable cell line which constitutively expresses E7 in HaCaT human keratinocyte cell
line and identified various relevant factors including oxygen modulators affected by the E7 oncogene. E7-expressing HaCaT
cells (HaCaT/E7) appeared to be more resistant to H2O2-induced cell death. Here, we demonstrate how E7 oncogene would modulate oxidative stress-induced cell death. In addition,
we verified the increased expression of catalase in the HaCaT/E7 by Western blot analysis. The results suggest that the E7
oncogene would induce higher resistance to ROS-induced cell injury in the E7-infected cells via the upregulation of catalase.
To investigate these paradoxical effects of high concentrations of H2O2 (500 μM–1 mM), we examined their effects on receptor mediated apoptosis, cell death via the mitochondrial pathway and modulation
of apoptosis related factors. Our results revealed that HaCaT keratinocytes infected with HPV 16 E7 oncogene modulated expressions
of catalase, Bcl-xL, IL-18, Fas, Bad, and cytochrome c as well as NF-κB, resulting in the resistance to oxidative stress-induced
cell death.
Authors’ address: Dr. Do-Young Yoon, Laboratory of Cell and Immunobiochemistry, Department of Bioscience and Biotechnology,
Konkuk University, Hwayang-dong 1, Gwangjin-gu, Seoul 143-701, Korea 相似文献
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The bivalve Pseudopythina macrophthalmensis (Galeommatoidea) is a commensal with the crab Macrophthalmus convexus (Ocypodidae) in Okinawa Prefecture, Japan. It is a protandric hermaphrodite which incubates the 65-μm large ova in the suprabranchial
cavity. The species produces two types of sperm, which were studied with the electron microscope. The euspermatozoon has an
elongate 2.8-μm-long, pointed acrosome, a slender 12- to 13-μm-long nucleus and a middlepiece containing several closely packed
mitochondria arranged as a 5.5- to 6.0-μm-long sheath around the basis of the flagellum. The paraspermato- zoon is vermiform,
220-μm-long and up to 5-μm-broad. Anteriorly there is a ca 7-μm-long bullet-shaped acrosome followed by a subcylindrical 3.0-
to 4.7-μm-long nucleus. Adjacent to the nucleus occurs a bundle of 26–42 40-μm-long flagella. The cytoplasm is packed with
spherical lipid droplets and ovoid granules of unknown composition. Sperm of both types aggregate to form spermatozeugmata,
which were found in the posterior mantle cavity or in paired seminal receptacles. Within the receptacles the euspermatozoa
dissociate themselves from the spermatozeugma and become attached to the epithelial lining of the receptacle whereas the paraspermatozoa
presumably disintegrate. The possible significance of the two types of sperm is discussed in the light of their presumed functions
in gastropods.
Accepted: 9 November 2000 相似文献
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《生物安全学报》2011,(3):176
1. Contact Information Department of Biological Invasion, Institute of Plant Protection, Chinese Academy of Agricultural Sciences (IPP, CAAS), #12 South Street of Zhong-Guan-Cun, Beijing, 100081, China Phone: +86-10-82109572; Fax: +86-10-82105927 E-mail: guifenzhang3@163.com 相似文献
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Using pulse radiolysis technique, the reaction between hydroxyl radical and 7 phenylpropanoidglycosides: echinacoside, verbascoside, leucosceptoside A, martynoside, pediculariosides A, M and N which were isolated from Pedicularis were examined. The rate constants of these reactions were determined by transient absorption spectra. All 7 phenylpropanoid glycosides react with hydroxyl radical at high rate constants within (0.97-1.91)×1010L · mol-1 · s-1. suggesting that they are effective hydroxyl radical scavengers. The results demonstrate that the numbers of phenolic hydroxyl groups of phenylpropanoid glycosides are directly related to their scavenging activities. The scavenging activities are likely related to o-dihydroxy group of phenylpropanoid glycosides as well. 相似文献
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Xiujun Zhang ;Lijun Meng ;Baoling He ;Jing Chen ;Peng Liu ;Jie Zhao ;Yufen Zhang ;Ming Li ;Dong An 《Acta biochimica et biophysica Sinica》2009,(5):362-369
Activation of the P2X7 receptor leads to a rapid, bidirectional flux of cations, causing broad range of biological responses including cytotoxicity. However, the mechanism of P2X7-mediated cytotoxicity remains largely unexplored. In our previous study, the lack of P2X7-mediated calcium response under normal conditions was found in P2X7+ hematopoietic cell lines. In this study, the P2X7-mediated cytotoxicity in different type of cells (P2X7-, P2X7+ with calcium response, and P2X7+ without calcium response) was investigated. Our results showed that P2X7 agonists, adenosine 5'-triphosphate (ATP) or 2',3'-O-(4 benzoylbenzoyl)- ATP, dose-dependently reduced the cell viability in all P2X7+ cells tested, including J6-1, LCL, and Namalva cells which are negative for P2X7-mediated calcium response, although these effects were lower than those observed in KGla cells which has normal P2X7 func- tions. The cytotoxic effect could be blocked by P2X7 antagonists, oxidized ATP and 1-[N,O-bis(5-isoquinolinesulfonyl)-N-methyl-L-tyrosyl]-4-phenylpiperazine. In addition, externalization of phosphatidylserine could be detected in a time-dependent manner and apoptotic morphological changes could be observed after the activation of P2X7 receptor in J6-1 cells. Furthermore, P2X7-mediated pore formation could be detected in KGla and J6-1 cells under low-ionic conditions, but not under low-divalent conditions. These effects could not be observed in P2X7- Ramos cells. These results suggested that P2X7 receptor-mediated cytotoxic effects may occur independent of calcium response. 相似文献
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The present article tests the following general assumption:plant taxa with different specializations towards mycorrhizal interactions should have different root syndromes.Roots of 61 species common in boreal zone were studied:16 species of Poaceae,24 species of Cyperaceae,14 species of Orchidaceae,and7 species of Iridaceae.Using a fixed material of 5 individuals of each species,the following was determined:number of orders of branching roots;transverse dimensions of root,stele and cortex;number ... 相似文献
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黄山贡菊的挥发油成分 总被引:9,自引:0,他引:9
The volatile oil in flowers of Dendranthema morifolium (Ramat) Tzvel. cv. Gongju was extracted with steam distillation, the constituents and contents of volatile oil were analyzed by means of GC-MS-DS techniques. The result shows that the principle constituents of the volatile oil are bicyclo[3.1. 1]hept-2-en-4-ol, 2,6,6-trimethyl-, acetate (39.64%); benzene, 1-( 1,5-dimethyl-4-hexenyl)-4-methyl-,2-heptene (5.24%);n-hexadecanoic acid (4.77%); cis-lanceol (4.73%) ; acetic acid,1,7, 7-trimethyl-bicyclo [2.2.1] hept-2-yl-ester (3.95%); (-) spathulenol (3.38%) ; 2, 4, 6-trimethyl-3-cyclohexene-1-carboxaldehyde(3.22%) ; caryophyllene oxide (2.88%) ; 1,2,3,4, 5,6,7,8-octahydro-1,4-dimethyl-7-(1-methylethenyl)-,azulene (2. 80%); 3-(1, 5-dimethyl-4-hexenyl)-6-methylene, cyclohexaene (2. 50%); decahydro-1, 4a-dimethyl-7-( 1-methylidene)-,1-naphthalenol(2.39%);1,1,2-trimethyl-3,5-bis(1-methylethenyl)-,cyclohexane(2.23% ), etc. 相似文献
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Vats P Mukherjee AK Kumria MM Singh SN Patil SK Rangnathan S Sridharan K 《International journal of biometeorology》1999,42(4):205-209
Exposure to high altitude causes loss of body mass and alterations in metabolic processes, especially carbohydrate and protein
metabolism. The present study was conducted to elucidate the role of glutamine synthetase, glutaminase and glycogen synthetase
under conditions of chronic intermittent hypoxia. Four groups, each consisting of 12 male albino rats (Wistar strain), were
exposed to a simulated altitude of 7620 m in a hypobaric chamber for 6 h per day for 1, 7, 14 and 21 days, respectively. Blood
haemoglobin, blood glucose, protein levels in the liver, muscle and plasma, glycogen content, and glutaminase, glutamine synthetase
and glycogen synthetase activities in liver and muscle were determined in all groups of exposed and in a group of unexposed
animals. Food intake and changes in body mass were also monitored. There was a significant reduction in body mass (28–30%)
in hypoxia-exposed groups as compared to controls, with a corresponding decrease in food intake. There was rise in blood haemoglobin
and plasma protein in response to acclimatisation. Over a three-fold increase in liver glycogen content was observed following
1 day of hypoxic exposure (4.76±0.78 mg·g−1 wet tissue in normal unexposed rats; 15.82±2.30 mg·g−1 wet tissue in rats exposed to hypoxia for 1 day). This returned to normal in later stages of exposure. However, there was
no change in glycogen synthetase activity except for a decrease in the 21-days hypoxia-exposed group. There was a slight increase
in muscle glycogen content in the 1-day exposed group which declined significantly by 56.5, 50.6 and 42% following 7, 14,
and 21 days of exposure, respectively. Muscle glycogen synthetase activity was also decreased following 21 days of exposure.
There was an increase in glutaminase activity in the liver and muscle in the 7-, 14- and 21-day exposed groups. Glutamine
synthetase activity was higher in the liver in 7- and 14-day exposed groups; this returned to normal following 21 days of
exposure. Glutamine synthetase activity in muscle was significantly higher in the 14-day exposed group (4.32 μmol γ-glutamyl
hydroxamate formed·g protein−1·min−1) in comparison to normal (1.53 μmol γ-glutamyl hydroxamate formed·g protein−1·min−1); this parameter had decreased by 40% following 21 days of exposure. These results suggest that since no dramatic changes
in the levels of protein were observed in the muscle and liver, there is an alteration in glutaminase and glutamine synthetase
activity in order to maintain nitrogen metabolism in the initial phase of hypoxic exposure.
Received: 30 March 1998 / Revised: 18 November 1998 / Accepted: 25 November 1998 相似文献
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南太湖浮游植物特征及其富营养化评价 总被引:3,自引:0,他引:3
《生态学杂志》2009,28(11)
2008年8-9月对南太湖的浮游植物进行了调查,并对9个采样点水样进行了分析.结果表明:共有浮游植物47种,隶属于7门28属,其中蓝藻门 6属9种,绿藻门10属13种,硅藻门7属18种,裸藻门2属3种,隐藻门 1属2种,金藻门1种,甲藻门1种;南太湖浮游植物的密度为3.56×10~6~7.99×10~6 cells·L~(-1);浮游植物的Shannon-Weaver多样性指数为0.29~2.27,均匀度指数在多数位点<0.5,卡尔森营养状态指数(TSIM)均大于64;根据浮游植物的优势种组成、密度、多样性指数及富营养状态指数的评价结果说明南太湖处于富营养化阶段.Abstract: In August-September 2008, an investigation was made on the phytoplankton in south-ern Taihu Lake, and the water quality at nine sampling sites was analyzed. A total of 47 phyto-plankton species belonging to 28 genera and 7 phylums were collected, with 9 species of Cyano-phyta, 13 species of Chlorophyta, 18 species of Diatoms, 3 species of Euglenophyta, 2 species of Cryptophyta, 1 specie of Chrysophyta, and 1 specie of Dinophyta. The phytoplankton density was 3.56×10~6-7.99×10~6 cells·L~(-1), Shannon-Weaver index was 0. 29-2. 77, evenness was low-er than 0. 5, and trophic state index (TSIM) was higher than 64. Based on the evaluation of the dominant species composition, density, and Shannon-Weaver index of phytoplankton, and of the TSIM, the southern Taihu Lake was considered at the stage of eutrophication. 相似文献
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Ecotoxicity of soils contaminated with industrial and domestic wastewater in western Shenyang, China
SONG Yufang ZHOU Qixing GONG Ping & SUN Tieheng Key Laboratory of Terrestrial Ecological Processes Institute of Applied Ecology Chinese Academy of Sciences Shenyang China Analytical Services Inc. Halls Ferry Road Vicksburg Mississippi USA Key Laboratory of Environmental Engineering of Shenyang Shenyang University Shenyang China 《中国科学:生命科学英文版》2005,48(Z1)
Soil samples were collected from 7 sites in the up-, mid- and down-reach along and nearby the wastewater irrigation channel, western Shenyang of China. The concentrations of selected pollutants (mineral oil, PAHs - polycycle aromatic hydrocarbons and Cd) were determined by UV spectrometer, HPLC and AAS (atomic adsorption spectrometer) spectrometer, respectively. Toxicity effects of soils were evaluated by seedling emergence test with root length of wheat as the end-point and by earthworms test with the mortality rate and inhibition rates of body weight as endpoints. Results showed accumulation of pollutants for most soils with concentration of 200.2 mg·kg-1-1600 mg·kg-1 for mineral oil, 0.33 mg·kg-1-1.81 mg·kg-1 for Cd and 900.16 mg·kg-1 -2737.91 mg·kg-1 for PAHs. The inhibition rates of root elongation were from -20% up to 40 %, and mortality rates of earthworms ranged from 0%-40% from the exposure period of two weeks to eight weeks by sampling interval of two weeks, the inhibition rates of earthw 相似文献
15.
《中国科学:生命科学英文版》2008,(8)
To investigate the regulation of estrogen, progesterone and prolactin stimulating the development of mammary gland, the Kunming mice were used as experimental animals in this study.Through the ex-periment in vitro, the effect of mammogenic hormones were systematically investigated on expression of FGF7 and FGF10 and their receptor in different periods.The results are as follows:in mammary glands of mice, 17 beta-estradiol increased the expression of FGF7;progesterone did not affect the expression of FGF7;prolactin up-regulated the expression of FGF7 significantly in pregnancy and lac-tation.17 beta-estradiol increased the expression of FGF10;progesterone and prolactin reduced the expression of FGF10 significantly in virgin;prolactin significantly increased the expression of FGF10 in pregnancy.When 17 beta-estradiol in the body was in relatively high proportion, it would lower the ex-pression of KGFR;while 17 beta-estradiol in the body was in relatively low proportion, it would increase the expression of KGFR.Low concentration of progesterone increased the expression of KGFR and high progesterone did not affect the expression of KGFR.Prolactin increased the expression of KGFR significantly in pregnancy and lactation. 相似文献
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WANG Jing XIANG Fengning XIA Guangmin & CHEN Huimin School of Life Sciences Shandong University Jinan China 《中国科学:生命科学英文版》2004,47(5):434-441
~~Transfer of small chromosome fragments of Agropyron elongatum to wheat chromosome via asymmetric somatic hybridization1 .Dong,Y.C,GenePools of common wheat,Journal of Triticeae CroPs(in Chinese),2000,20(3):78-81.
2 .Wei,Y.M.,Zheng,YL.Zhou,R.H., Detectlon of the rye chro- matin in multisPikelet wheat germplasm 10-A background using fluorescence in situ hybridization(FISH)and RFLP markers,Acta Bot.Sinica(in Chinese),1999,41(7):722-725.
3 .Xiang,E N.,Xia,G M.… 相似文献
18.
《亚洲两栖爬行动物研究(英文版)》2015,(2)
<正>Asian Herpetological Research(AHR),an international English language journal,is published quarterly by the Chengdu Institute of Biology(CIB),Chinese Academy of Sciences and the Science Press of China,cooperated with the Asiatic Herpetological Research Society(AHRS),with its registered numbers:CN 51-1735/Q and ISSN 2095-0357,and post distribution code:62-218.AHR has an international Editorial Board consisting of many top 相似文献
19.
大熊猫初乳免疫球蛋白含量及其动态变化 总被引:3,自引:1,他引:3
This paper first reports that the contents of slgA, IgC and IgM of 3 giant pandas'colostrums from day 1 to day 14 unconsecutively which have been determined by the method of “A Rate Nephelometer for Measuring Specific Protein by Immunopmciptin Reaction”. The results indicated that slgA is the most important immunuoglobulins of giant panda's colostmms, and IgG, IgM are also the major components of giant panda's colostrums. The contents of immunoglobulins in colostrums of giant pandas vary with the day : 1) the content of colostral sIgA is in the highest level (1 442.93 mg/dl) in 1st day, and maintains a higher level (1 200- 1 300 mg/dl) from 2nd day to 5th day, it drops abruptly in 7th day (727.61 mg/dl) ; 2) the content of colostral IgG is in the hingest level (861.5 mg/dl), and maintains in a higher level(648.74- 707.07 mg/dl) from 2nd day to 5th day, but drops abruptly in 7th day (375.14 mg/dl) ; 3) the content of colostral tgM varies rarely and maintains in a stable level during the first postpartum 5 days, and drops abruptly in 7th day . Based on the changes of immtmoglobulins in giant panda's milks, the author conclude that milks from 1st day to 5th day postpartum should be giant panda's colostrums. 相似文献
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《World journal of biological chemistry》2012,(12):181-184
<正>2009-2013 The World Journal of Biological Chemistry Editorial Board consists of 529 members, representing a team of worldwide experts in biochemistry and molecular biology. They are from 40 countries, including Argentina (1), Australia (7), Austria (2), Belgium (6), Brazil (5), Bulgaria (1), Canada 相似文献