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1.
Considerable evidence for shared antigenic determinants between nervous elements and lymphocytes has accumulated. It has also been suggested that this cross-recognition may be involved in the pathogenesis of human neurological diseases such as myasthenia gravis and multiple sclerosis. We report here evidence that a marker for natural killer (NK) cells, anti-Leu-7 (HNK-1), specifically binds to components of human and rodent central nervous tissue as well as peripheral nervous tissue, especially to myelin sheaths. In contrast, another NK-cell marker (VEP13) did not react with nervous tissue. Since NK-cell function is impaired in a population of multiple sclerosis patients, the observed cross-reactivity indicates that autosensitization against myelin may simultaneously cause a defect of NK-cell function. Furthermore, the shared antigenic determinant may help to identify a hitherto undefined nervous tissue antigen and simultaneously increase the knowledge about the nature of NK-cell antigens. 相似文献
2.
This paper presents systematically a method for image compression/decompression viawavelet transform.It consists of filter,quantization and Huffman coding etc..Different methodshave been compared.Finally,some suggestions for further studies are proposed.In fact,the paper isa summary of our recent research. 相似文献
3.
Identification of ten loci associated with height highlights new biological pathways in human growth 总被引:1,自引:0,他引:1
Lettre G Jackson AU Gieger C Schumacher FR Berndt SI Sanna S Eyheramendy S Voight BF Butler JL Guiducci C Illig T Hackett R Heid IM Jacobs KB Lyssenko V Uda M;Diabetes Genetics Initiative;FUSION;KORA;Prostate Lung Colorectal Ovarian Cancer Screening Trial;Nurses' Health Study;SardiNIA Boehnke M Chanock SJ Groop LC Hu FB Isomaa B Kraft P Peltonen L Salomaa V Schlessinger D Hunter DJ Hayes RB Abecasis GR Wichmann HE Mohlke KL Hirschhorn JN 《Nature genetics》2008,40(5):584-591
Height is a classic polygenic trait, reflecting the combined influence of multiple as-yet-undiscovered genetic factors. We carried out a meta-analysis of genome-wide association study data of height from 15,821 individuals at 2.2 million SNPs, and followed up the strongest findings in >10,000 subjects. Ten newly identified and two previously reported loci were strongly associated with variation in height (P values from 4 x 10(-7) to 8 x 10(-22)). Together, these 12 loci account for approximately 2% of the population variation in height. Individuals with < or =8 height-increasing alleles and > or =16 height-increasing alleles differ in height by approximately 3.5 cm. The newly identified loci, along with several additional loci with strongly suggestive associations, encompass both strong biological candidates and unexpected genes, and highlight several pathways (let-7 targets, chromatin remodeling proteins and Hedgehog signaling) as important regulators of human stature. These results expand the picture of the biological regulation of human height and of the genetic architecture of this classical complex trait. 相似文献
4.
Early experience and immunity 总被引:5,自引:0,他引:5
5.
Wolkovich EM Cook BI Allen JM Crimmins TM Betancourt JL Travers SE Pau S Regetz J Davies TJ Kraft NJ Ault TR Bolmgren K Mazer SJ McCabe GJ McGill BJ Parmesan C Salamin N Schwartz MD Cleland EE 《Nature》2012,485(7399):494-497
Warming experiments are increasingly relied on to estimate plant responses to global climate change. For experiments to provide meaningful predictions of future responses, they should reflect the empirical record of responses to temperature variability and recent warming, including advances in the timing of flowering and leafing. We compared phenology (the timing of recurring life history events) in observational studies and warming experiments spanning four continents and 1,634 plant species using a common measure of temperature sensitivity (change in days per degree Celsius). We show that warming experiments underpredict advances in the timing of flowering and leafing by 8.5-fold and 4.0-fold, respectively, compared with long-term observations. For species that were common to both study types, the experimental results did not match the observational data in sign or magnitude. The observational data also showed that species that flower earliest in the spring have the highest temperature sensitivities, but this trend was not reflected in the experimental data. These significant mismatches seem to be unrelated to the study length or to the degree of manipulated warming in experiments. The discrepancy between experiments and observations, however, could arise from complex interactions among multiple drivers in the observational data, or it could arise from remediable artefacts in the experiments that result in lower irradiance and drier soils, thus dampening the phenological responses to manipulated warming. Our results introduce uncertainty into ecosystem models that are informed solely by experiments and suggest that responses to climate change that are predicted using such models should be re-evaluated. 相似文献
6.
Stolk L Perry JR Chasman DI He C Mangino M Sulem P Barbalic M Broer L Byrne EM Ernst F Esko T Franceschini N Gudbjartsson DF Hottenga JJ Kraft P McArdle PF Porcu E Shin SY Smith AV van Wingerden S Zhai G Zhuang WV Albrecht E Alizadeh BZ Aspelund T Bandinelli S Lauc LB Beckmann JS Boban M Boerwinkle E Broekmans FJ Burri A Campbell H Chanock SJ Chen C Cornelis MC Corre T Coviello AD d'Adamo P Davies G de Faire U de Geus EJ Deary IJ Dedoussis GV Deloukas P Ebrahim S Eiriksdottir G Emilsson V 《Nature genetics》2012,44(3):260-268
To newly identify loci for age at natural menopause, we carried out a meta-analysis of 22 genome-wide association studies (GWAS) in 38,968 women of European descent, with replication in up to 14,435 women. In addition to four known loci, we identified 13 loci newly associated with age at natural menopause (at P < 5 × 10(-8)). Candidate genes located at these newly associated loci include genes implicated in DNA repair (EXO1, HELQ, UIMC1, FAM175A, FANCI, TLK1, POLG and PRIM1) and immune function (IL11, NLRP11 and PRRC2A (also known as BAT2)). Gene-set enrichment pathway analyses using the full GWAS data set identified exoDNase, NF-κB signaling and mitochondrial dysfunction as biological processes related to timing of menopause. 相似文献
7.
Kraft B Johswich A Kauczor G Scharenberg M Gerardy-Schahn R Bakker H 《Cellular and molecular life sciences : CMLS》2011,68(24):4091-4100
The glycolipid specific Drosophila melanogaster β1,4-N-acetylgalactosaminyltransferase B (β4GalNAcTB) depends on a zinc finger DHHC protein family member named GalNAcTB pilot (GABPI)
for activity and translocation to the Golgi. The six-membrane spanning protein actually lacks the cysteine in the cytoplasmic
DHHC motif, displaying DHHS instead. Here we show that the whole conserved region around the DHHS sequence, which is essential
for palmitoylation in DHHC proteins, is not required for GABPI to interact with β4GalNAcTB. In contrast, the two luminal loops
between transmembrane domain 3–4 and 5–6 contain conserved amino acids, which are crucial for activity. Besides the dependence
on GABPI, β4GalNAcTB requires its exceptional short stem region for activity. A few hydrophobic amino acids positioned close
to the transmembrane domain are essential for the interaction with GABPI. Along with its catalytic domain, β4GalNAcTB, thus,
requires an area in its own stem region and two small luminal loops of GABPI as "add-on" domains. Moreover, some inactive
GABPI mutants could be rescued by fusion with β4GalNAcTB, indicating their importance in direct GABPI-β4GalNAcTB interaction. 相似文献
8.
G. Fráter 《复旦学报(自然科学版)》2005,44(5):775-776
1 Introduction Chiral recognition of substrates is one of the most characteristic phenomena of biological activity. And one of the most fundamental biological activities of chemical substances is their smell. In 1991, Linda Buck and Richard Axel~([1]) discovered a large multigene family that en codes odorant receptors, for which they were awarded the 2004 Nobel Prize in Medicine and Physiology. These odorant receptors are highly homologous, consist of ca. 320 amino acids, and show a heptah… 相似文献
9.
The forecasting of prices for electricity balancing reserve power can essentially improve the trading positions of market participants in competitive auctions. Having identified a lack of literature related to forecasting balancing reserve prices, we deploy approaches originating from econometrics and artificial intelligence and set up a forecasting framework based on autoregressive and exogenous factors. We use SARIMAX models as well as neural networks with different structures and forecast based on a rolling one-step forecast with reestimation of the models. It turns out that the naive forecast performs reasonably well but is outperformed by the more advanced models. In addition, neural network approaches outperform the econometric approach in terms of forecast quality, whereas for the further use of the generated models the econometric approach has advantages in terms of explaining price drivers. For the present application, more advanced configurations of the neural networks are not able to further improve the forecasting performance. 相似文献
10.
Iterative methods are popular choices in image reconstruction fields due to their capability of recovering object information from incomplete acquisition data.However,the computation process involves frequent uses of forward and backward projections that are computationally expensive.Past research has proved that a forward projector that can produce high quality images is crucial to achieve a good convergence rate.In this paper a high performance iterative reconstruction framework is introduced,where two mo... 相似文献