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排序方式: 共有143条查询结果,搜索用时 15 毫秒
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Hollox EJ Huffmeier U Zeeuwen PL Palla R Lascorz J Rodijk-Olthuis D van de Kerkhof PC Traupe H de Jongh G den Heijer M Reis A Armour JA Schalkwijk J 《Nature genetics》2008,40(1):23-25
Psoriasis is a common inflammatory skin disease with a strong genetic component. We analyzed the genomic copy number polymorphism of the beta-defensin region on human chromosome 8 in 179 Dutch individuals with psoriasis and 272 controls and in 319 German individuals with psoriasis and 305 controls. Comparisons in both cohorts showed a significant association between higher genomic copy number for beta-defensin genes and risk of psoriasis. 相似文献
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Mühlebach MD Mateo M Sinn PL Prüfer S Uhlig KM Leonard VH Navaratnarajah CK Frenzke M Wong XX Sawatsky B Ramachandran S McCray PB Cichutek K von Messling V Lopez M Cattaneo R 《Nature》2011,480(7378):530-533
Measles virus is an aerosol-transmitted virus that affects more than 10 million children each year and accounts for approximately 120,000 deaths. Although it was long believed to replicate in the respiratory epithelium before disseminating, it was recently shown to infect initially macrophages and dendritic cells of the airways using signalling lymphocytic activation molecule family member 1 (SLAMF1; also called CD150) as a receptor. These cells then cross the respiratory epithelium and transport the infection to lymphatic organs where measles virus replicates vigorously. How and where the virus crosses back into the airways has remained unknown. On the basis of functional analyses of surface proteins preferentially expressed on virus-permissive human epithelial cell lines, here we identify nectin-4 (ref. 8; also called poliovirus-receptor-like-4 (PVRL4)) as a candidate host exit receptor. This adherens junction protein of the immunoglobulin superfamily interacts with the viral attachment protein with high affinity through its membrane-distal domain. Nectin-4 sustains measles virus entry and non-cytopathic lateral spread in well-differentiated primary human airway epithelial sheets infected basolaterally. It is downregulated in infected epithelial cells, including those of macaque tracheae. Although other viruses use receptors to enter hosts or transit through their epithelial barriers, we suggest that measles virus targets nectin-4 to emerge in the airways. Nectin-4 is a cellular marker of several types of cancer, which has implications for ongoing measles-virus-based clinical trials of oncolysis. 相似文献
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BRADLEY PL 《Nature》1957,180(4599):1418-1419
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运用质量权重法对原有的各气流组织评价指标进行修正,以充分发挥数值模拟技术的优势来评价气流组织的性能。建立了数值模型并通过实验验证了模型的准确性。用该数值模型模拟嵌入式空调室内机4种不同工况下的室内气流组织,计算、比较了这4种工况下的原气流组织评价指标值与修正后的指标值,发现修正前、后指标值差异显著,且这些差异导致了评价这4种气流组织结果的不同。分析结果表明,用修正后的评价指标来评价气流组织更加准确、科学。 相似文献
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A fundamental feature of the mammalian neocortex is its columnar organization. In the visual cortex, functional columns consisting of neurons with similar orientation preferences have been characterized extensively, but how these columns are constructed during development remains unclear. The radial unit hypothesis posits that the ontogenetic columns formed by clonally related neurons migrating along the same radial glial fibre during corticogenesis provide the basis for functional columns in adult neocortex. However, a direct correspondence between the ontogenetic and functional columns has not been demonstrated. Here we show that, despite the lack of a discernible orientation map in mouse visual cortex, sister neurons in the same radial clone exhibit similar orientation preferences. Using a retroviral vector encoding green fluorescent protein to label radial clones of excitatory neurons, and in vivo two-photon calcium imaging to measure neuronal response properties, we found that sister neurons preferred similar orientations whereas nearby non-sister neurons showed no such relationship. Interestingly, disruption of gap junction coupling by viral expression of a dominant-negative mutant of Cx26 (also known as Gjb2) or by daily administration of a gap junction blocker, carbenoxolone, during the first postnatal week greatly diminished the functional similarity between sister neurons, suggesting that the maturation of ontogenetic into functional columns requires intercellular communication through gap junctions. Together with the recent finding of preferential excitatory connections among sister neurons, our results support the radial unit hypothesis and unify the ontogenetic and functional columns in the visual cortex. 相似文献
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