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1.
We tested 310,605 SNPs for association in 778 individuals with celiac disease and 1,422 controls. Outside the HLA region, the most significant finding (rs13119723; P = 2.0 x 10(-7)) was in the KIAA1109-TENR-IL2-IL21 linkage disequilibrium block. We independently confirmed association in two further collections (strongest association at rs6822844, 24 kb 5' of IL21; meta-analysis P = 1.3 x 10(-14), odds ratio = 0.63), suggesting that genetic variation in this region predisposes to celiac disease.  相似文献   
2.
In recent times, a particular attention has been devoted to thesignificance of Quantum Theory for other disciplines. The articlescollected in this issue discuss some interesting cases,characterized by an interaction between Quantum Theory andother fields. Some basic notrons of the mathematical formalismof the theory are here summarized.  相似文献   
3.
Atmospheric aerosols exert an important influence on climate through their effects on stratiform cloud albedo and lifetime and the invigoration of convective storms. Model calculations suggest that almost half of the global cloud condensation nuclei in the atmospheric boundary layer may originate from the nucleation of aerosols from trace condensable vapours, although the sensitivity of the number of cloud condensation nuclei to changes of nucleation rate may be small. Despite extensive research, fundamental questions remain about the nucleation rate of sulphuric acid particles and the mechanisms responsible, including the roles of galactic cosmic rays and other chemical species such as ammonia. Here we present the first results from the CLOUD experiment at CERN. We find that atmospherically relevant ammonia mixing ratios of 100 parts per trillion by volume, or less, increase the nucleation rate of sulphuric acid particles more than 100-1,000-fold. Time-resolved molecular measurements reveal that nucleation proceeds by a base-stabilization mechanism involving the stepwise accretion of ammonia molecules. Ions increase the nucleation rate by an additional factor of between two and more than ten at ground-level galactic-cosmic-ray intensities, provided that the nucleation rate lies below the limiting ion-pair production rate. We find that ion-induced binary nucleation of H(2)SO(4)-H(2)O can occur in the mid-troposphere but is negligible in the boundary layer. However, even with the large enhancements in rate due to ammonia and ions, atmospheric concentrations of ammonia and sulphuric acid are insufficient to account for observed boundary-layer nucleation.  相似文献   
4.
Coats plus is a highly pleiotropic disorder particularly affecting the eye, brain, bone and gastrointestinal tract. Here, we show that Coats plus results from mutations in CTC1, encoding conserved telomere maintenance component 1, a member of the mammalian homolog of the yeast heterotrimeric CST telomeric capping complex. Consistent with the observation of shortened telomeres in an Arabidopsis CTC1 mutant and the phenotypic overlap of Coats plus with the telomeric maintenance disorders comprising dyskeratosis congenita, we observed shortened telomeres in three individuals with Coats plus and an increase in spontaneous γH2AX-positive cells in cell lines derived from two affected individuals. CTC1 is also a subunit of the α-accessory factor (AAF) complex, stimulating the activity of DNA polymerase-α primase, the only enzyme known to initiate DNA replication in eukaryotic cells. Thus, CTC1 may have a function in DNA metabolism that is necessary for but not specific to telomeric integrity.  相似文献   
5.
The filamins are cytoplasmic proteins that regulate the structure and activity of the cytoskeleton by cross-linking actin into three-dimensional networks, linking the cell membrane to the cytoskeleton and serving as scaffolds on which intracellular signaling and protein trafficking pathways are organized (reviewed in refs. 1,2). We identified mutations in the gene encoding filamin B in four human skeletal disorders. We found homozygosity or compound heterozygosity with respect to stop-codon mutations in autosomal recessive spondylocarpotarsal syndrome (SCT, OMIM 272460) and missense mutations in individuals with autosomal dominant Larsen syndrome (OMIM 150250) and the perinatal lethal atelosteogenesis I and III phenotypes (AOI, OMIM 108720; AOIII, OMIM 108721). We found that filamin B is expressed in human growth plate chondrocytes and in the developing vertebral bodies in the mouse. These data indicate an unexpected role in vertebral segmentation, joint formation and endochondral ossification for this ubiquitously expressed cytoskeletal protein.  相似文献   
6.
A 20-Myr record of creation of oceanic lithosphere is exposed along a segment of the central Mid-Atlantic Ridge on an uplifted sliver of lithosphere. The degree of melting of the mantle that is upwelling below the ridge, estimated from the chemistry of the exposed mantle rocks, as well as crustal thickness inferred from gravity measurements, show oscillations of approximately 3-4 Myr superimposed on a longer-term steady increase with time. The time lag between oscillations of mantle melting and crustal thickness indicates that the mantle is upwelling at an average rate of approximately 25 mm x yr(-1), but this appears to vary through time. Slow-spreading lithosphere seems to form through dynamic pulses of mantle upwelling and melting, leading not only to along-axis segmentation but also to across-axis structural variability. Also, the central Mid-Atlantic Ridge appears to have become steadily hotter over the past 20 Myr, possibly owing to north-south mantle flow.  相似文献   
7.
The effect of gamma-rays on iron-free conalbumin was studied by isoelectric focusing technique. The results obtained can be interpreted on the basis of radiation-induced conformational changes of the macromolecules through a cleavage of disulphide bridges. Treatments with reagents acting on disulphide bridges lead to isoelectric focusing patterns that confirm this hypothesis.  相似文献   
8.
Cornelia de Lange syndrome is a multisystem developmental disorder characterized by facial dysmorphisms, upper limb abnormalities, growth delay and cognitive retardation. Mutations in the NIPBL gene, a component of the cohesin complex, account for approximately half of the affected individuals. We report here that mutations in SMC1L1 (also known as SMC1), which encodes a different subunit of the cohesin complex, are responsible for CdLS in three male members of an affected family and in one sporadic case.  相似文献   
9.
Summary Peroxidase activity was investigated by the use of diaminobenzidine method in fixed cells of Prototheca moriformis. A strong peroxidase activity was observed in the mitochondria. DAB staining was unaffected by KCN, aminotriazole and antimycin A, but it was completely inhibited by methanol-nitroferricyanide.  相似文献   
10.
Summary Quinic acid methyl ester, having the 1.4 and 5 hydroxy-groups suitably blocked, was condensed with the carbonilcaffeic acid chloride.Gradual hydrolysis of the condensation compound gave place to chlorogenic acid.  相似文献   
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