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31.
We have previously reported multiple loci associated with prostate cancer susceptibility in a Japanese population using a genome-wide association study (GWAS). To identify additional prostate cancer susceptibility loci, we genotyped nine SNPs that were nominally associated with prostate cancer (P < 1 × 10(-4)) in our previous GWAS in three independent studies of prostate cancer in Japanese men (2,557 individuals with prostate cancer (cases) and 3,003 controls). In a meta-analysis of our previous GWAS and the replication studies, which included a total of 7,141 prostate cancer cases and 11,804 controls from a single ancestry group, three new loci reached genome-wide significance on chromosomes 11q12 (rs1938781; P = 1.10 × 10(-10); FAM111A-FAM111B), 10q26 (rs2252004; P = 1.98 × 10(-8)) and 3p11.2 (rs2055109; P = 3.94 × 10(-8)). We also found suggestive evidence of association at a previously reported prostate cancer susceptibility locus at 2p11 (rs2028898; P = 1.08 × 10(-7)). The identification of three new susceptibility loci should provide additional insight into the pathogenesis of prostate cancer and emphasizes the importance of conducting GWAS in diverse populations.  相似文献   
32.
Summary In high doses synthetic vitamin A proved to have a leucopoetic effect on the experimental leucopenia of rats. In the treatment of the succinylsulfathiazol leucopenia vitamin A does not equal the effect of folic acid, in the treatment of the milk leucopenia however it is superior to the latter.  相似文献   
33.
PLC步进式伺服系统的研究   总被引:1,自引:0,他引:1  
本文主要研究可编程序控制器(PLC)在步进式伺服系统中的应用。提出采用EX100PLC主机,辅以32点DC输出模块(DO32)或轴向定位模块(MC11)来控制步进电机,并用于精密磨床的进给控制的两种方案,分别进行了硬软件设计、完成实验室试验,并对两种控制方案的特点进行了分析研究。  相似文献   
34.
Quasirational dynamic system   总被引:1,自引:0,他引:1  
Using the iterations of quasirational mappings, the theorems on dynamic system are generalized to the quasirational dynamic system. Some different results are also obtained.  相似文献   
35.
刘洪波  罗宏 《贵州科学》1998,16(4):266-271
研究电解锌过程中电解液锰离子浓度对阳极保护层MnO2沉积的形态、形成机理、对铅阳极的保护作用和对阴极锌质量的影响。指出ZnSO4电解液[Mn^2+]应该保持在3 ̄5g/L,并注意维持在整个系统中该浓度下的锰平衡。  相似文献   
36.
不同品种小麦幼穗离体培养的研究   总被引:3,自引:0,他引:3  
通过对(李杂3号×晋2148)×(豫麦1号×Alondvas)、京花1号、晋2148、豫麦18号、陕农7859、冀麦5418、豫麦13号、Alondvas和花培28九种不同品种的小麦幼穗在N6培养基中进行体外培养,发现山不同的小麦幼穗脱分化所形成的愈伤组织之间有明显的差异,其再分化出根和苗的能力也各不相同。其中以(李杂3号×晋2148)×(豫麦1号×Alondvas)、晋2148、京花1号、豫麦18号和陕农7859五个品种小麦幼穗所形成的愈伤组织生长状况较佳,冀麦5418和豫麦13号次之,Alondvas和花培28愈伤组织长势较弱。再分化的能力与愈伤组织的生长情况呈相对应之关系。  相似文献   
37.
ARC syndrome (OMIM 208085) is an autosomal recessive multisystem disorder characterized by neurogenic arthrogryposis multiplex congenita, renal tubular dysfunction and neonatal cholestasis with bile duct hypoplasia and low gamma glutamyl transpeptidase (gGT) activity. Platelet dysfunction is common. Affected infants do not thrive and usually die in the first year of life. To elucidate the molecular basis of ARC, we mapped the disease to a 7-cM interval on 15q26.1 and then identified germline mutations in the gene VPS33B in 14 kindreds with ARC. VPS33B encodes a homolog of the class C yeast vacuolar protein sorting gene, Vps33, that contains a Sec1-like domain important in the regulation of vesicle-to-target SNARE complex formation and subsequent membrane fusion.  相似文献   
38.
Bico J  Roman B  Moulin L  Boudaoud A 《Nature》2004,432(7018):690
We investigated why wet hair clumps into bundles by dunking a model brush of parallel elastic lamellae into a perfectly wetting liquid. As the brush is withdrawn, pairs of bundles aggregate successively, forming complex hierarchical patterns that depend on a balance between capillary forces and the elasticity of the lamellae. This capillary-driven self-assembly of flexible structures, which occurs in the tarsi of insects and in biomimetic adhesives but which can also damage micro-electromechanical structures or carbon nanotube 'carpets', represents a new type of coalescence process.  相似文献   
39.
Adaptive immunity depends on T-cell exit from the thymus and T and B cells travelling between secondary lymphoid organs to survey for antigens. After activation in lymphoid organs, T cells must again return to circulation to reach sites of infection; however, the mechanisms regulating lymphoid organ exit are unknown. An immunosuppressant drug, FTY720, inhibits lymphocyte emigration from lymphoid organs, and phosphorylated FTY720 binds and activates four of the five known sphingosine-1-phosphate (S1P) receptors. However, the role of S1P receptors in normal immune cell trafficking is unclear. Here we show that in mice whose haematopoietic cells lack a single S1P receptor (S1P1; also known as Edg1) there are no T cells in the periphery because mature T cells are unable to exit the thymus. Although B cells are present in peripheral lymphoid organs, they are severely deficient in blood and lymph. Adoptive cell transfer experiments establish an intrinsic requirement for S1P1 in T and B cells for lymphoid organ egress. Furthermore, S1P1-dependent chemotactic responsiveness is strongly upregulated in T-cell development before exit from the thymus, whereas S1P1 is downregulated during peripheral lymphocyte activation, and this is associated with retention in lymphoid organs. We find that FTY720 treatment downregulates S1P1, creating a temporary pharmacological S1P1-null state in lymphocytes, providing an explanation for the mechanism of FTY720-induced lymphocyte sequestration. These findings establish that S1P1 is essential for lymphocyte recirculation and that it regulates egress from both thymus and peripheral lymphoid organs.  相似文献   
40.
Walter F  Bertoldi F  Carilli C  Cox P  Lo KY  Neri R  Fan X  Omont A  Strauss MA  Menten KM 《Nature》2003,424(6947):406-408
Observations of molecular hydrogen in quasar host galaxies at high redshifts provide fundamental constraints on galaxy evolution, because it is out of this molecular gas that stars form. Molecular hydrogen is traced by emission from the carbon monoxide molecule, CO; cold H2 itself is generally not observable. Carbon monoxide has been detected in about ten quasar host galaxies with redshifts z > 2; the record-holder is at z = 4.69 (refs 1-3). Here we report CO emission from the quasar SDSS J114816.64 + 525150.3 (refs 5, 6) at z = 6.42. At that redshift, the Universe was only 1/16 of its present age, and the era of cosmic reionization was just ending. The presence of about 2 x 1010 M\circ of H2 in an object at this time demonstrates that molecular gas enriched with heavy elements can be generated rapidly in the youngest galaxies.  相似文献   
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