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61.
Whole-genome sequence of Schistosoma haematobium 总被引:1,自引:0,他引:1
Young ND Jex AR Li B Liu S Yang L Xiong Z Li Y Cantacessi C Hall RS Xu X Chen F Wu X Zerlotini A Oliveira G Hofmann A Zhang G Fang X Kang Y Campbell BE Loukas A Ranganathan S Rollinson D Rinaldi G Brindley PJ Yang H Wang J Wang J Gasser RB 《Nature genetics》2012,44(2):221-225
Schistosomiasis is a neglected tropical disease caused by blood flukes (genus Schistosoma; schistosomes) and affecting 200 million people worldwide. No vaccines are available, and treatment relies on one drug, praziquantel. Schistosoma haematobium has come into the spotlight as a major cause of urogenital disease, as an agent linked to bladder cancer and as a predisposing factor for HIV/AIDS. The parasite is transmitted to humans from freshwater snails. Worms dwell in blood vessels and release eggs that become embedded in the bladder wall to elicit chronic immune-mediated disease and induce squamous cell carcinoma. Here we sequenced the 385-Mb genome of S. haematobium using Illumina-based technology at 74-fold coverage and compared it to sequences from related parasites. We included genome annotation based on function, gene ontology, networking and pathway mapping. This genome now provides an unprecedented resource for many fundamental research areas and shows great promise for the design of new disease interventions. 相似文献
62.
Brown KM Macgregor S Montgomery GW Craig DW Zhao ZZ Iyadurai K Henders AK Homer N Campbell MJ Stark M Thomas S Schmid H Holland EA Gillanders EM Duffy DL Maskiell JA Jetann J Ferguson M Stephan DA Cust AE Whiteman D Green A Olsson H Puig S Ghiorzo P Hansson J Demenais F Goldstein AM Gruis NA Elder DE Bishop JN Kefford RF Giles GG Armstrong BK Aitken JF Hopper JL Martin NG Trent JM Mann GJ Hayward NK 《Nature genetics》2008,40(7):838-840
We conducted a genome-wide association pooling study for cutaneous melanoma and performed validation in samples totaling 2,019 cases and 2,105 controls. Using pooling, we identified a new melanoma risk locus on chromosome 20 (rs910873 and rs1885120), with replication in two further samples (combined P < 1 x 10(-15)). The per allele odds ratio was 1.75 (1.53, 2.01), with evidence for stronger association in early-onset cases. 相似文献
63.
B. C. Campbell 《Cellular and molecular life sciences : CMLS》1986,42(4):451-452
Summary The honeydew of the aphidSchizaphis graminum (Rondani) contains hetero-oligosaccharides (mol. wt>2200 D) having neutral sugar and uronic acid compositions similar to the pectic substances of the host plant,Sorghum biocolor (L.) Moench. These oligosaccharides are pectic fragments which result from the depolymerization of pectic substances in the phloem by aphid salivary polysaccharases. 相似文献
64.
Summary Increased methylation of middle lamellar pectin in plants hinders aphids in penetrating host-plant tissue. In sorghum, a new aphid biotype has overcome this host-plant barrier by having increased pectin methylesterase activity. Results suggest that resistance in crop-plants against sap-feeding insects may possibly be manipulated by altering middle lamellar chemistry either through breeding or use of certain plant-growth regulators. 相似文献
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66.
P S Campbell 《Experientia》1983,39(1):108-109
Rats treated neonatally with testosterone propionate exhibit a reduced uterine growth response to estradiol administration prepubertally. This androgen-induced impairment is the consequence of developmental effects on both the ovary and the hypothalamic-pituitary complex, although the latter is the more sensitive. 相似文献
67.
X-ray structure of a ClC chloride channel at 3.0 A reveals the molecular basis of anion selectivity. 总被引:11,自引:0,他引:11
Raimund Dutzler Ernest B Campbell Martine Cadene Brian T Chait Roderick MacKinnon 《Nature》2002,415(6869):287-294
The ClC chloride channels catalyse the selective flow of Cl- ions across cell membranes, thereby regulating electrical excitation in skeletal muscle and the flow of salt and water across epithelial barriers. Genetic defects in ClC Cl- channels underlie several familial muscle and kidney diseases. Here we present the X-ray structures of two prokaryotic ClC Cl- channels from Salmonella enterica serovar typhimurium and Escherichia coli at 3.0 and 3.5 A, respectively. Both structures reveal two identical pores, each pore being formed by a separate subunit contained within a homodimeric membrane protein. Individual subunits are composed of two roughly repeated halves that span the membrane with opposite orientations. This antiparallel architecture defines a selectivity filter in which a Cl- ion is stabilized by electrostatic interactions with alpha-helix dipoles and by chemical coordination with nitrogen atoms and hydroxyl groups. These findings provide a structural basis for further understanding the function of ClC Cl- channels, and establish the physical and chemical basis of their anion selectivity. 相似文献
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69.
The gene ST7 has recently been implicated as the broad-range tumor suppressor on human chromosome 7q31.1. We did not detect somatic mutations in ST7 in any of 149 primary ovarian, breast or colon carcinomas. These data suggest that epigenetic downregulation or haploinsufficiency, rather than somatic genetic alterations, may be the primary mechanism of abrogation of ST7 function in these tumor types. 相似文献
70.