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51.
Rheumatoid arthritis is a common autoimmune disease characterized by chronic inflammation. We report a meta-analysis of genome-wide association studies (GWAS) in a Japanese population including 4,074 individuals with rheumatoid arthritis (cases) and 16,891 controls, followed by a replication in 5,277 rheumatoid arthritis cases and 21,684 controls. Our study identified nine loci newly associated with rheumatoid arthritis at a threshold of P < 5.0 × 10(-8), including B3GNT2, ANXA3, CSF2, CD83, NFKBIE, ARID5B, PDE2A-ARAP1, PLD4 and PTPN2. ANXA3 was also associated with susceptibility to systemic lupus erythematosus (P = 0.0040), and B3GNT2 and ARID5B were associated with Graves' disease (P = 3.5 × 10(-4) and 2.9 × 10(-4), respectively). We conducted a multi-ancestry comparative analysis with a previous meta-analysis in individuals of European descent (5,539 rheumatoid arthritis cases and 20,169 controls). This provided evidence of shared genetic risks of rheumatoid arthritis between the populations.  相似文献   
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Arylsulfatase activities in biological materials are too low to be detected by the methods available hitherto. A sensitive and specific assay method for arylsulfatase A (AS-A) has been developed in the present study. Ascorbate-2-sulfate is known to be a specific natural substrate of AS-A; the ascorbic acid liberated by the action of AS-A was quantitatively determined using HPLC equipped with an amperometric detector. The method was used to analyze the activity of AS-A in biological materials.  相似文献   
55.
Summary Peptidase and esterase activities of elastase were each altered separately by the ionic strength of the buffer used. The esterase activity is exerted in a lower ionic strength medium where the peptidase activity is not detected.  相似文献   
56.
Structure of the core and central channel of bacterial flagella   总被引:30,自引:0,他引:30  
K Namba  I Yamashita  F Vonderviszt 《Nature》1989,342(6250):648-654
X-ray fibre diffraction analysis of bacterial flagellar filaments has allowed the subunit packing and secondary structure arrangement in the filament core to be determined. The central hole, presumably a channel for flagellin transport, is large enough to accommodate the folded elongated flagellin molecules during their transport to the distal end for filament growth.  相似文献   
57.
《大明历》计算了回归年长度,其主要方法是应用了“率”.《大明历》的数学部分是从以前的数学、特别是刘徽的数学思想延伸出来的.如果祖冲之计算圆周率方法与刘徽一样,应该计算到圆内接正两万四千五百七十六边形的面积.但不管增加多少有效数位,用定点运算,都不能计算出这一结果.有可能祖冲之利用了刘徽的“率”.  相似文献   
58.
Determining the chronology for the assembly of planetary bodies in the early Solar System is essential for a complete understanding of star- and planet-formation processes. Various radionuclide chronometers (applied to meteorites) have been used to determine that basaltic lava flows on the surface of the asteroid Vesta formed within 3 million years (3 Myr) of the origin of the Solar System. Such rapid formation is broadly consistent with astronomical observations of young stellar objects, which suggest that formation of planetary systems occurs within a few million years after star formation. Some hafnium-tungsten isotope data, however, require that Vesta formed later (approximately 16 Myr after the formation of the Solar System) and that the formation of the terrestrial planets took a much longer time (62(-14)(+4504) Myr). Here we report measurements of tungsten isotope compositions and hafnium-tungsten ratios of several meteorites. Our measurements indicate that, contrary to previous results, the bulk of metal-silicate separation in the Solar System was completed within <30 Myr. These results are completely consistent with other evidence for rapid planetary formation, and are also in agreement with dynamic accretion models that predict a relatively short time (approximately 10 Myr) for the main growth stage of terrestrial planet formation.  相似文献   
59.
Summary A new rapid method for measuring intra-cellular water content by gas chromatography and an isotopic (3H-sucrose) technique is described. Water content of circulating red cells was revealed to be 71.26±0.31%. Intra-cellular water content increased to 102.9% of its original value following addition of 3 volumes of acid-citrate-dextrose (ACD) to 20 volumes of blood.  相似文献   
60.
One-to-one binding of a purified scorpion toxin to Na channels   总被引:1,自引:0,他引:1  
H Okamoto  K Takahashi  N Yamashita 《Nature》1977,266(5601):465-468
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