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91.
Hillier LW Fulton RS Fulton LA Graves TA Pepin KH Wagner-McPherson C Layman D Maas J Jaeger S Walker R Wylie K Sekhon M Becker MC O'Laughlin MD Schaller ME Fewell GA Delehaunty KD Miner TL Nash WE Cordes M Du H Sun H Edwards J Bradshaw-Cordum H Ali J Andrews S Isak A Vanbrunt A Nguyen C Du F Lamar B Courtney L Kalicki J Ozersky P Bielicki L Scott K Holmes A Harkins R Harris A Strong CM Hou S Tomlinson C Dauphin-Kohlberg S Kozlowicz-Reilly A Leonard S Rohlfing T Rock SM Tin-Wollam AM Abbott A 《Nature》2003,424(6945):157-164
92.
Epithelial supporting cells can differentiate into outer hair cells and Deiters' cells in the cultured organ of Corti 总被引:2,自引:0,他引:2
Malgrange B Thiry M Van De Water TR Nguyen L Moonen G Lefebvre PP 《Cellular and molecular life sciences : CMLS》2002,59(10):1744-1757
The organ of Corti is a complex structure containing a single row of inner hair cells (IHCs) and three rows of outer hair
cells (OHCs), supported respectively by one row of inner phalangeal cells and three rows of Deiters' cells. When fetal rat
organ of Corti explants are cultured, supernumerary OHCs and supernumerary Deiters' cells are produced, without any additional
cell proliferation. Analysis of semi- and ultrathin sections revealed that supernumerary OHCs are produced at the distal edge
of the organ of Corti. Quantitative analysis of cell types present in the organ of Corti demonstrates that when the number
of OHCs increases: (i) the total number of cells remains constant; (ii) the number of Deiters' cells increases; (iii) the
number of tectal cells decreases and of Hensen's cells decreases. Using specific HC markers, i.e. jagged2 (Jag2) and Math1,
we showed that in addition to existing OHCs, supernumerary OHCs, tectal cells and Hensen's cells expressed these markers in
embryonic day 19 organ of Corti explants after 5 days in vitro. The results of this study suggest that Hensen's cells retain
the capacity to differentiate into either tectal cells, which differentiate into OHCs, or into undertectal cells which differentiate
into Deiters' cells.
Received 15 May 2002; received after revision 18 July 2002; accepted 7 August 2002
RID="*"
ID="*"Corresponding author. 相似文献
93.
The spectrum of infection with Aeromonas and Plesiomonas included gastroenteritis, bacteremia, biliary tract infection, perirectal infection, and disseminated disease. Most patients (86%) with bacteremia were neutropenic (less than 500 PMN/mm3). Colonization of stools and sputum also occurred. Therapy with aminoglycosides, beta-lactams, trimethoprim/sulfamethoxazole, and the newer quinolones was effective in patients with AIDS and cancer. 相似文献
94.
This paper shows for the first time the presence of progesterone receptors in the foetal guinea-pig uterus, as well as the stimulation of progesterone receptors in foetal uterus in animals treated with oestradiol. 相似文献
95.
Nusbaum C Zody MC Borowsky ML Kamal M Kodira CD Taylor TD Whittaker CA Chang JL Cuomo CA Dewar K FitzGerald MG Yang X Abouelleil A Allen NR Anderson S Bloom T Bugalter B Butler J Cook A DeCaprio D Engels R Garber M Gnirke A Hafez N Hall JL Norman CH Itoh T Jaffe DB Kuroki Y Lehoczky J Lui A Macdonald P Mauceli E Mikkelsen TS Naylor JW Nicol R Nguyen C Noguchi H O'Leary SB O'Neill K Piqani B Smith CL Talamas JA Topham K Totoki Y Toyoda A Wain HM Young SK Zeng Q Zimmer AR Fujiyama A Hattori M 《Nature》2005,437(7058):551-555
Chromosome 18 appears to have the lowest gene density of any human chromosome and is one of only three chromosomes for which trisomic individuals survive to term. There are also a number of genetic disorders stemming from chromosome 18 trisomy and aneuploidy. Here we report the finished sequence and gene annotation of human chromosome 18, which will allow a better understanding of the normal and disease biology of this chromosome. Despite the low density of protein-coding genes on chromosome 18, we find that the proportion of non-protein-coding sequences evolutionarily conserved among mammals is close to the genome-wide average. Extending this analysis to the entire human genome, we find that the density of conserved non-protein-coding sequences is largely uncorrelated with gene density. This has important implications for the nature and roles of non-protein-coding sequence elements. 相似文献
96.
Genesis of a highly pathogenic and potentially pandemic H5N1 influenza virus in eastern Asia 总被引:4,自引:0,他引:4
Li KS Guan Y Wang J Smith GJ Xu KM Duan L Rahardjo AP Puthavathana P Buranathai C Nguyen TD Estoepangestie AT Chaisingh A Auewarakul P Long HT Hanh NT Webby RJ Poon LL Chen H Shortridge KF Yuen KY Webster RG Peiris JS 《Nature》2004,430(6996):209-213
A highly pathogenic avian influenza virus, H5N1, caused disease outbreaks in poultry in China and seven other east Asian countries between late 2003 and early 2004; the same virus was fatal to humans in Thailand and Vietnam. Here we demonstrate a series of genetic reassortment events traceable to the precursor of the H5N1 viruses that caused the initial human outbreak in Hong Kong in 1997 (refs 2-4) and subsequent avian outbreaks in 2001 and 2002 (refs 5, 6). These events gave rise to a dominant H5N1 genotype (Z) in chickens and ducks that was responsible for the regional outbreak in 2003-04. Our findings indicate that domestic ducks in southern China had a central role in the generation and maintenance of this virus, and that wild birds may have contributed to the increasingly wide spread of the virus in Asia. Our results suggest that H5N1 viruses with pandemic potential have become endemic in the region and are not easily eradicable. These developments pose a threat to public and veterinary health in the region and potentially the world, and suggest that long-term control measures are required. 相似文献
97.
Gibbs RA Weinstock GM Metzker ML Muzny DM Sodergren EJ Scherer S Scott G Steffen D Worley KC Burch PE Okwuonu G Hines S Lewis L DeRamo C Delgado O Dugan-Rocha S Miner G Morgan M Hawes A Gill R Celera Holt RA Adams MD Amanatides PG Baden-Tillson H Barnstead M Chin S Evans CA Ferriera S Fosler C Glodek A Gu Z Jennings D Kraft CL Nguyen T Pfannkoch CM Sitter C Sutton GG Venter JC Woodage T Smith D Lee HM Gustafson E Cahill P Kana A Doucette-Stamm L Weinstock K Fechtel K Weiss RB Dunn DM Green ED 《Nature》2004,428(6982):493-521
The laboratory rat (Rattus norvegicus) is an indispensable tool in experimental medicine and drug development, having made inestimable contributions to human health. We report here the genome sequence of the Brown Norway (BN) rat strain. The sequence represents a high-quality 'draft' covering over 90% of the genome. The BN rat sequence is the third complete mammalian genome to be deciphered, and three-way comparisons with the human and mouse genomes resolve details of mammalian evolution. This first comprehensive analysis includes genes and proteins and their relation to human disease, repeated sequences, comparative genome-wide studies of mammalian orthologous chromosomal regions and rearrangement breakpoints, reconstruction of ancestral karyotypes and the events leading to existing species, rates of variation, and lineage-specific and lineage-independent evolutionary events such as expansion of gene families, orthology relations and protein evolution. 相似文献
98.
Theologis A Ecker JR Palm CJ Federspiel NA Kaul S White O Alonso J Altafi H Araujo R Bowman CL Brooks SY Buehler E Chan A Chao Q Chen H Cheuk RF Chin CW Chung MK Conn L Conway AB Conway AR Creasy TH Dewar K Dunn P Etgu P Feldblyum TV Feng J Fong B Fujii CY Gill JE Goldsmith AD Haas B Hansen NF Hughes B Huizar L Hunter JL Jenkins J Johnson-Hopson C Khan S Khaykin E Kim CJ Koo HL Kremenetskaia I Kurtz DB Kwan A Lam B Langin-Hooper S Lee A Lee JM Lenz CA Li JH Li Y Lin X Liu SX Liu ZA Luros JS 《Nature》2000,408(6814):816-820
The genome of the flowering plant Arabidopsis thaliana has five chromosomes. Here we report the sequence of the largest, chromosome 1, in two contigs of around 14.2 and 14.6 megabases. The contigs extend from the telomeres to the centromeric borders, regions rich in transposons, retrotransposons and repetitive elements such as the 180-base-pair repeat. The chromosome represents 25% of the genome and contains about 6,850 open reading frames, 236 transfer RNAs (tRNAs) and 12 small nuclear RNAs. There are two clusters of tRNA genes at different places on the chromosome. One consists of 27 tRNA(Pro) genes and the other contains 27 tandem repeats of tRNA(Tyr)-tRNA(Tyr)-tRNA(Ser) genes. Chromosome 1 contains about 300 gene families with clustered duplications. There are also many repeat elements, representing 8% of the sequence. 相似文献
99.
100.
ABSTRACT We describe a new species of rhacophorid frogs from Nghe An Province in northern Vietnam based on morphological and molecular evidences. Morphologically, Kurixalus gracilloides sp. nov. is distinguished from its congeners by a combination of the following diagnostic characters: body size small (snout–vent length 27.9–31.2 mm in males); head width subequal to head length; snout rounded with no dermal projection; canthus rostralis distinct, curved; vomerine teeth present; single internal vocal sac; iris golden-brown; small nuptial pad in finger I; dorsal surfaces golden-brown with a saddle-shaped dark marking; large dark spots on ventral surfaces absent; dermal fringes along outer edge of limbs; conical dermal appendage at the heel; skin on dorsum rough; skin on throat and chest granular; finger webbing rudimentary and toe webbing moderately developed, webbing formula I 2–2½ II 1½–3 III 1¾–3½ IV 3–1½ V. The new species is separated from all other congeners by uncorrected genetic distances ranging from 5.4% to 12.7% based on mitochondrial 16S rRNA gene. Phylogenetic analyses of mtDNA suggest that the new species is nested within a clade of Taiwanese and Yunnan Kurixalus with strong support values. The new species is currently known only from secondary bamboo forest in Pu Mat National Park, northern Vietnam, at elevations of 150 m asl. We suggest the new species should be considered as Near Threatened (NT) following the IUCN’s Red List categories. http://www.zoobank.org/urn:lsid:zoobank.org:pub:C1BF843F-2F31-4CED-B1F9-13A9035C77C9 相似文献