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101.
McKay JD Hung RJ Gaborieau V Boffetta P Chabrier A Byrnes G Zaridze D Mukeria A Szeszenia-Dabrowska N Lissowska J Rudnai P Fabianova E Mates D Bencko V Foretova L Janout V McLaughlin J Shepherd F Montpetit A Narod S Krokan HE Skorpen F Elvestad MB Vatten L Njølstad I Axelsson T Chen C Goodman G Barnett M Loomis MM Lubiñski J Matyjasik J Lener M Oszutowska D Field J Liloglou T Xinarianos G Cassidy A;EPIC Study Vineis P Clavel-Chapelon F Palli D Tumino R Krogh V Panico S González CA 《Nature genetics》2008,40(12):1404-1406
We carried out a genome-wide association study of lung cancer (3,259 cases and 4,159 controls), followed by replication in 2,899 cases and 5,573 controls. Two uncorrelated disease markers at 5p15.33, rs402710 and rs2736100 were detected by the genome-wide data (P = 2 x 10(-7) and P = 4 x 10(-6)) and replicated by the independent study series (P = 7 x 10(-5) and P = 0.016). The susceptibility region contains two genes, TERT and CLPTM1L, suggesting that one or both may have a role in lung cancer etiology. 相似文献
102.
基于节能偏好的冲突多目标相容温室环境控制 总被引:1,自引:0,他引:1
在温室环境控制问题中,传统的控制方法追求精确的点目标控制,而精确的控制精度是以高的能量消耗为代价的。针对温室环境控制这一实际问题,采用多目标相容控制算法来进行控制。因为在相容控制算法中点控制目标被放宽到区间内,所以有很大的余地来协调控制精度和能耗。为了满足相容控制算法在控制过程中节能偏好的需要,对遗传算法进行了改进,把节能这一偏好信息引入到了优化过程中、参与进化寻优。通过对经典温室模型仿真,验证了新算法在节能降耗方面的优势。 相似文献
103.
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105.
Sequence of the human insulin gene 总被引:47,自引:0,他引:47
The human insulin gene contains two intervening sequences, one is within the region transcribed into the 5'-untranslated segment of the mRNA and the other interrupts the C-peptide encoding region. A comparison of the human with the rat insulin genes indicates potential regulatory regions in the DNA segment preceding the gene and suggests that the ancestral form of the insulin gene had two intervening sequences. 相似文献
106.
Phylogenetic origins and adaptive evolution of avian and mammalian haemoglobin genes 总被引:20,自引:0,他引:20
J Czelusniak M Goodman D Hewett-Emmett M L Weiss P J Venta R E Tashian 《Nature》1982,298(5871):297-300
Recent years have seen rapid growth in amino acid sequence data on globins and nucleotide sequence data on haemoglobin genes and pseudogenes, and cladistic analysis of these data continues to reveal new facets of globin evolution. Our present findings demonstrate: (1) avian and mammalian embryonic alpha genes (pi and xi, respectively) had a monophyletic origin involving an alpha locus duplication about 400 Myr ago soon after the duplication which separated alpha and beta genes; (2) much later in phylogeny, independent beta-gene duplications produced the embryonic rho locus of birds and embryonic epsilon and fetal gamma loci of mammals. This parallels the earlier finding that myoglobins evolved more than once from generalized globin ancestors. Here we support the view that such globin evolution resulted from natural selection acting on mutations in duplicated genes. Thus, our evidence contradicts the neutralist view in which almost all amino acid substitutions in descent to extant globins evaded positive selection. 相似文献
107.
Cell determination and regulation during development of neuroblasts and neurones in grasshopper embryo 总被引:1,自引:0,他引:1
The embryonic development of the central nervous system (CNS) involves the generation of an enormous diversity of cellular types arranged and interconnected in a remarkably precise pattern. In each hemisegment of the grasshopper embryo, the ectoderm generates a stereotyped pattern of 30 neuronal precursor cells, called neuroblasts (Fig. 1). Each of these stem cells makes a stereotyped contribution of 6-100 progeny to the approximately 1,000 different neurones, each cell identifiable according to its unique morphology, physiology and biochemistry. What are the contributions of cell interactions and cell lineage to the generation of this diversity and specificity of identified neurones in the grasshopper CNS? Here we report on cell ablations with a laser microbeam at different stages of development. Our results suggest the importance of cell-cell interactions in the determination of ectodermal cells to become identified neuroblasts. However, once a neuroblast begins to divide, then cell lineage appears to play an important role in the determination of its stereotyped family of neuronal progeny. Furthermore, cell-specific interactions continue to play an important role as neurones, according to their mitotic ancestry, recognize and interact with other differentiating neurones in their environment. 相似文献
108.
Zusammenfassung Verschiedene biochemische und elektronenoptische Techniken wurden dazu benützt, eine partikuläre Speicherform für Glukose inPhysarum polycephalum zu identifizieren. Die Ergebnisse zeigen, dass es sich um Glykogen handelt. 相似文献
109.
Primate eta-globin DNA sequences and man's place among the great apes 总被引:22,自引:0,他引:22
Molecular studies indicate that chimpanzee and gorilla are the closest relatives of man (refs 1-7 and refs therein). The small molecular distances found point to late ancestral separations, with the most recent being between chimpanzee and man, as judged by DNA hybridization. Kluge and Schwartz contest these conclusions: morphological characters group a chimpanzee-gorilla clade with the Asian ape orang-utan in Kluge's cladistic study and with an orang-utan-human clade in Schwartz's study. Clearly, extensive sequencing of nuclear DNA is needed to resolve by cladistic analysis the branching order within Hominoidea. Towards this goal, we are sequencing orthologues of the primate psi eta-globin locus. Here, we compare the newly completed sequences of orang-utan and rhesus monkey with human, chimpanzee, gorilla, owl monkey, lemur and goat orthologues. Our findings substantially increase the evidence indicative of a human-chimpanzee-gorilla clade with ancestral separations around 8 to 6 Myr ago. We also verify that neutral hominoid DNA evolved at markedly retarded rates. 相似文献
110.
Chlorination inhibitors in Streptomyces aureofaciens 总被引:1,自引:0,他引:1