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排序方式: 共有129条查询结果,搜索用时 15 毫秒
81.
This paper describes an investigation in the fabric longi-tudinal compressibility of thirty-one suiting and trouse-ring materials using a newly developed device attached to the advanced Instron extensometer Model4466.The at-tachment was designed mainly to ensure a correct align-meat of fabric plane at the start of compression.Usingthe newly developed testing method,fabric longitudinalcompression curve was obtained and the results of longi-tudinal compressibility measured by two different com-pression load ranges(from 0 to 0.5 N/m width and 0 to1 N/m width)were examined.In addition,their rela-tionships with the fabric low-stress mechanical proper-ties measured by the KES-F system were investigatedusing statistical analysis.The results clearly indicatedthat significant differences existed when substituting fab-ric longitudinal compressibility with fabric extensibilitymeasured using the KES-F system under a low-load.Significant infiuence of yarn rotational movement in fab-ric on the longitudinal compressibi 相似文献
82.
In twisting a yarn running over a guide surface, the twist inserted into the part in front of the guide is impeded to transmit freely to the part behind the contact zone. A new device has been set up for investigating twist blockage and yarn torque - twist simultaneously. Measurements of twist blockage in relationship to different parameters have been carried out by using a monofilament yarn and a multifilament yarn. The factors under consideration include the wrap angle, yarn tension and input twist. 相似文献
83.
Northcott PA Shih DJ Peacock J Garzia L Morrissy AS Zichner T Stütz AM Korshunov A Reimand J Schumacher SE Beroukhim R Ellison DW Marshall CR Lionel AC Mack S Dubuc A Yao Y Ramaswamy V Luu B Rolider A Cavalli FM Wang X Remke M Wu X Chiu RY Chu A Chuah E Corbett RD Hoad GR Jackman SD Li Y Lo A Mungall KL Nip KM Qian JQ Raymond AG Thiessen NT Varhol RJ Birol I Moore RA Mungall AJ Holt R Kawauchi D Roussel MF Kool M Jones DT Witt H Fernandez-L A Kenney AM Wechsler-Reya RJ Dirks P Aviv T 《Nature》2012,488(7409):49-56
Medulloblastoma, the most common malignant paediatric brain tumour, is currently treated with nonspecific cytotoxic therapies including surgery, whole-brain radiation, and aggressive chemotherapy. As medulloblastoma exhibits marked intertumoural heterogeneity, with at least four distinct molecular variants, previous attempts to identify targets for therapy have been underpowered because of small samples sizes. Here we report somatic copy number aberrations (SCNAs) in 1,087 unique medulloblastomas. SCNAs are common in medulloblastoma, and are predominantly subgroup-enriched. The most common region of focal copy number gain is a tandem duplication of SNCAIP, a gene associated with Parkinson's disease, which is exquisitely restricted to Group 4α. Recurrent translocations of PVT1, including PVT1-MYC and PVT1-NDRG1, that arise through chromothripsis are restricted to Group 3. Numerous targetable SCNAs, including recurrent events targeting TGF-β signalling in Group 3, and NF-κB signalling in Group 4, suggest future avenues for rational, targeted therapy. 相似文献
84.
DSPP mutation in dentinogenesis imperfecta Shields type II 总被引:12,自引:0,他引:12
We identified a nonsense mutation (Gln45stop) in exon 3 of the dentin sialophosphoprotein (DSPP) gene in a Chinese family with dentinogenesis imperfecta Shields type II (DGI-II), in which the affected members showed discoloration and severe attrition of their teeth, with obliterated pulp chambers. 相似文献
85.
影响系统安全的组织因素分析 总被引:3,自引:0,他引:3
探讨影响系统安全的组织因素问题。根据建立起来的影响系统安全的组织因素层次模型,运用灰色系统理论中的关联分析方法,以某核电站近几年的内部事件报告为例,对影响系统安全的组织因素进行了分析,结果显示:影响安全的组织因素主要体现在技术操作层次,对系统安全影响最大的主要子因素是标准与规程失效。同时,分析了同一主因素下的子关联情况,分析结论为预防和减少组织错误的发生提供了理论依据。 相似文献
86.
Seri M Cusano R Gangarossa S Caridi G Bordo D Lo Nigro C Ghiggeri GM Ravazzolo R Savino M Del Vecchio M d'Apolito M Iolascon A Zelante LL Savoia A Balduini CL Noris P Magrini U Belletti S Heath KE Babcock M Glucksman MJ Aliprandis E Bizzaro N Desnick RJ Martignetti JA 《Nature genetics》2000,26(1):103-105
The autosomal dominant, giant-platelet disorders, May-Hegglin anomaly (MHA; MIM 155100), Fechtner syndrome (FTNS; MIM 153640) and Sebastian syndrome (SBS), share the triad of thrombocytopenia, large platelets and characteristic leukocyte inclusions ('D?hle-like' bodies). MHA and SBS can be differentiated by subtle ultrastructural leukocyte inclusion features, whereas FTNS is distinguished by the additional Alport-like clinical features of sensorineural deafness, cataracts and nephritis. The similarities between these platelet disorders and our recent refinement of the MHA (ref. 6) and FTNS (ref. 7) disease loci to an overlapping region of 480 kb on chromosome 22 suggested that all three disorders are allelic. Among the identified candidate genes is the gene encoding nonmuscle myosin heavy chain 9 (MYH9; refs 8-10), which is expressed in platelets and upregulated during granulocyte differentiation. We identified six MYH9 mutations (one nonsense and five missense) in seven unrelated probands from MHA, SBS and FTNS families. On the basis of molecular modelling, the two mutations affecting the myosin head were predicted to impose electrostatic and conformational changes, whereas the truncating mutation deleted the unique carboxy-terminal tailpiece. The remaining missense mutations, all affecting highly conserved coiled-coil domain positions, imparted destabilizing electrostatic and polar changes. Thus, our results suggest that mutations in MYH9 result in three megakaryocyte/platelet/leukocyte syndromes and are important in the pathogenesis of sensorineural deafness, cataracts and nephritis. 相似文献
87.
本文采用哇巴因致豚鼠心律失常模型,以哇巴目致室性早搏量、致室颤量和致死量作为衡量洋地黄类毒性的指标,观察GSH、三七皂甙Rg_1、Rb_1和AA等自由基清除剂对洋地黄美毒性的影响。结果表明:GSH、三七皂甙Rg_1、Rb_1和AA对哇巴因所致的心律失常均有不同程度的对抗作用,可减轻洋地黄类毒性。提示自由基可能参与洋地黄类的毒性过程。 相似文献
88.
1991年5月至1992年5月,我院采用国产NE-Ⅳ型碎石机对146例尿路结石患者进行了229人次的原位碎石治疗。碎石成功率为98.63%,碎石术后3个月内肾上盏及肾盂排石率为68.99%,输尿管下段排石率为72.3%。本组结果表明,体外震波碎石治疗尿路结石安全、有效、并发症少。提高碎石疗效在于准确地B超定位及合理地选择适应症。 相似文献
89.
Zusammenfassung Aflatoxin B1 hemmt den Einbau von 1-14C-Azetat in die Lipide der menschlichen Haut. Wird aber3H-Azetyl-CoA als Vorstufe für den Lipideinbau verwendet, so kommt es zu keiner merklichen Hemmung. Die Azetataktivierung scheint somit die wichtigste, vom Toxin beeinflussbare Stufe der Lipidsynthese zu sein. 相似文献
90.
Lambrechts D Storkebaum E Morimoto M Del-Favero J Desmet F Marklund SL Wyns S Thijs V Andersson J van Marion I Al-Chalabi A Bornes S Musson R Hansen V Beckman L Adolfsson R Pall HS Prats H Vermeire S Rutgeerts P Katayama S Awata T Leigh N Lang-Lazdunski L Dewerchin M Shaw C Moons L Vlietinck R Morrison KE Robberecht W Van Broeckhoven C Collen D Andersen PM Carmeliet P 《Nature genetics》2003,34(4):383-394