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11.
M. E. Lowe D. H. S. Horn M. N. Galbraith 《Cellular and molecular life sciences : CMLS》1968,24(5):518-519
Résumé La crustecdysone injectée dans l'écrevisse,Procambarus sinulans ne cause pas la mue chez l'animal intact mais l'accélère après ablation des pédoncules oculaires. 相似文献
12.
A microRNA polycistron as a potential human oncogene 总被引:5,自引:0,他引:5
He L Thomson JM Hemann MT Hernando-Monge E Mu D Goodson S Powers S Cordon-Cardo C Lowe SW Hannon GJ Hammond SM 《Nature》2005,435(7043):828-833
To date, more than 200 microRNAs have been described in humans; however, the precise functions of these regulatory, non-coding RNAs remains largely obscure. One cluster of microRNAs, the mir-17-92 polycistron, is located in a region of DNA that is amplified in human B-cell lymphomas. Here we compared B-cell lymphoma samples and cell lines to normal tissues, and found that the levels of the primary or mature microRNAs derived from the mir-17-92 locus are often substantially increased in these cancers. Enforced expression of the mir-17-92 cluster acted with c-myc expression to accelerate tumour development in a mouse B-cell lymphoma model. Tumours derived from haematopoietic stem cells expressing a subset of the mir-17-92 cluster and c-myc could be distinguished by an absence of apoptosis that was otherwise prevalent in c-myc-induced lymphomas. Together, these studies indicate that non-coding RNAs, specifically microRNAs, can modulate tumour formation, and implicate the mir-17-92 cluster as a potential human oncogene. 相似文献
13.
The role of crustecdysone in the moulting crayfish 总被引:2,自引:0,他引:2
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Neuroectodermal signalling centres induce and pattern many novel vertebrate brain structures but are absent, or divergent, in invertebrate chordates. This has led to the idea that signalling-centre genetic programs were first assembled in stem vertebrates and potentially drove morphological innovations of the brain. However, this scenario presumes that extant cephalochordates accurately represent ancestral chordate characters, which has not been tested using close chordate outgroups. Here we report that genetic programs homologous to three vertebrate signalling centres-the anterior neural ridge, zona limitans intrathalamica and isthmic organizer-are present in the hemichordate Saccoglossus kowalevskii. Fgf8/17/18 (a single gene homologous to vertebrate Fgf8, Fgf17 and Fgf18), sfrp1/5, hh and wnt1 are expressed in vertebrate-like arrangements in hemichordate ectoderm, and homologous genetic mechanisms regulate ectodermal patterning in both animals. We propose that these genetic programs were components of an unexpectedly complex, ancient genetic regulatory scaffold for deuterostome body patterning that degenerated in amphioxus and ascidians, but was retained to pattern divergent structures in hemichordates and vertebrates. 相似文献
16.
The effects of near total blood replacement with the proprietary perfluorocarbon (PFC)-based emulsion, Fluosol-DA 20%, on plasma concentrations of 2 enzymes, lactate dehydrogeanse (LDH) and alkaline phosphatase (ALP), have been examined in conscious, chronically catheterized rats. A pronounced fall in both plasma LDH (p less than 0.05) an ALP (p less than 0.01) occurred in response to exchange-transfusion. However, at 6 h following blood replacement, plasma concentrations of both enzymes had risen to values significantly greater than those measured immediately before perfusion. The observed changes in plasma LDH and ALP after blood replacement with Fluosol-DA indicated alterations in normal functioning of tissues from which these enzymes originate. 相似文献
17.
Clinical implications of p53 mutations 总被引:5,自引:0,他引:5
The ultimate goal of basic cancer research is to provide a theoretical foundation for rational approaches to improve cancer
therapy. Our extensive insight into the biology of the p53 tumour suppressor and the clinical behaviour of tumours harbouring
p53 mutations indicates that information concerning p53 will be useful in diagnosis and prognosis, and may ultimately produce
new therapeutic strategies. At the same time, efforts to understand the clinical implications of p53 mutations have revealed conceptual and technical limitations in translating basic biology to the clinic. The lessons learned
from p53 may lay the groundwork for future efforts to synthesize cancer gene function, cancer genetics and cancer therapy. 相似文献
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Todd JA Walker NM Cooper JD Smyth DJ Downes K Plagnol V Bailey R Nejentsev S Field SF Payne F Lowe CE Szeszko JS Hafler JP Zeitels L Yang JH Vella A Nutland S Stevens HE Schuilenburg H Coleman G Maisuria M Meadows W Smink LJ Healy B Burren OS Lam AA Ovington NR Allen J Adlem E Leung HT Wallace C Howson JM Guja C Ionescu-Tîrgovişte C;Genetics of Type Diabetes in Finland Simmonds MJ Heward JM Gough SC;Wellcome Trust Case Control Consortium Dunger DB Wicker LS Clayton DG 《Nature genetics》2007,39(7):857-864
The Wellcome Trust Case Control Consortium (WTCCC) primary genome-wide association (GWA) scan on seven diseases, including the multifactorial autoimmune disease type 1 diabetes (T1D), shows associations at P < 5 x 10(-7) between T1D and six chromosome regions: 12q24, 12q13, 16p13, 18p11, 12p13 and 4q27. Here, we attempted to validate these and six other top findings in 4,000 individuals with T1D, 5,000 controls and 2,997 family trios independent of the WTCCC study. We confirmed unequivocally the associations of 12q24, 12q13, 16p13 and 18p11 (P(follow-up) 相似文献
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Prodigiosin condensing enzyme (PCE) activities were present in Serratia marcescens wild type 08, mutants OF, WF and 9-3-3. Their specific activities exhibited different maxima and at different times during the late log phase or the early stationary phase of cell growth. The levels of prodigiosin and its precursors also showed a significant increase at this period. The results support that prodigiosin and/or its precursors are secondary metabolites. The ubiquity of the PCE activity in mutants deficient in prodigiosin biosynthesis suggest that this particular enzyme may also be present in non-pigmented clinical isolates. 相似文献