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排序方式: 共有154条查询结果,搜索用时 31 毫秒
61.
Demin Zhou Shahbaz Khan Akhtar Abbas Tariq Rana Haiying Zhang Yun Chen 《自然科学进展(英文版)》2009,19(12):1773-1779
In this study,spatial analysis techniques were used to generate climatic zoning maps of the East Murrumbidgee Irrigation Area (MIA),Australia.Long term climate data were used to analyze and assess regional climatic variation by cluster analysis in a GIS environment.Based on thermal and moisture factors,four variables were chosen to develop climate zones.These variables include annual average rainfalls,annual average ETc,annual average Growing Day Degree (GDD) and daily average temperature generated from daily climate data of 36 years (1971-2006) on 12 local weather stations as the fundamental elements of regional climate characteristics.GIS-based spatial analysis models are used to map climate sub-regions from sets of climatic parameters derived from regional climate data sources.Two climate zoning schemes are presented by integration of spatial interpolation,spatial cluster analysis and climate indices methods.One scheme comes with the two climate zones of the West and the East based on spatial cluster analysis according to selected climatic variables,and the other comes with the three comprehensive hydro-thermal zones and the six hydro-thermal balance zones. 相似文献
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63.
京都协议已确认并应用战略战术措施来减少温室气的排放,因此,城市交通系统规划人员不得不寻求一种革新的方法来满足京都协议的要求。本文包括四部分:第一部分简要介绍了环境可持续的城市交通的概念,油耗,温室气体排放和京都协议的要求;第二部分描述了温室气体排放估测所需的方法,并指出了在实践中存在的缺陷,第三部分阐述了如何应用EMME/2作为平台来估测室气体的排放;最后第四部分作了总结。 相似文献
64.
Sanjay Kumar Bharti Irfan Khan Taraswi Banerjee Joshua A. Sommers Yuliang Wu Robert M. Brosh Jr. 《Cellular and molecular life sciences : CMLS》2014,71(14):2625-2639
In 2010, a new recessive cohesinopathy disorder, designated Warsaw breakage syndrome (WABS), was described. The individual with WABS displayed microcephaly, pre- and postnatal growth retardation, and abnormal skin pigmentation. Cytogenetic analysis revealed mitomycin C (MMC)-induced chromosomal breakage; however, an additional sister chromatid cohesion defect was also observed. WABS is genetically linked to bi-allelic mutations in the ChlR1/DDX11 gene which encodes a protein of the conserved family of Iron–Sulfur (Fe–S) cluster DNA helicases. Mutations in the budding yeast ortholog of ChlR1, known as Chl1, were known to cause sister chromatid cohesion defects, indicating a conserved function of the gene. In 2012, three affected siblings were identified with similar symptoms to the original WABS case, and found to have a homozygous mutation in the conserved Fe–S domain of ChlR1, confirming the genetic linkage. Significantly, the clinically relevant mutations perturbed ChlR1 DNA unwinding activity. In addition to its genetic importance in human disease, ChlR1 is implicated in papillomavirus genome maintenance and cancer. Although its precise functions in genome homeostasis are still not well understood, ongoing molecular studies of ChlR1 suggest the helicase plays a critically important role in cellular replication and/or DNA repair. 相似文献
65.
Park CC Ahn S Bloom JS Lin A Wang RT Wu T Sekar A Khan AH Farr CJ Lusis AJ Leahy RM Lange K Smith DJ 《Nature genetics》2008,40(4):421-429
We mapped regulatory loci for nearly all protein-coding genes in mammals using comparative genomic hybridization and expression array measurements from a panel of mouse-hamster radiation hybrid cell lines. The large number of breaks in the mouse chromosomes and the dense genotyping of the panel allowed extremely sharp mapping of loci. As the regulatory loci result from extra gene dosage, we call them copy number expression quantitative trait loci, or ceQTLs. The -2log10P support interval for the ceQTLs was <150 kb, containing an average of <2-3 genes. We identified 29,769 trans ceQTLs with -log10P > 4, including 13 hotspots each regulating >100 genes in trans. Further, this work identifies 2,761 trans ceQTLs harboring no known genes, and provides evidence for a mode of gene expression autoregulation specific to the X chromosome. 相似文献
66.
Ahmed ZM Masmoudi S Kalay E Belyantseva IA Mosrati MA Collin RW Riazuddin S Hmani-Aifa M Venselaar H Kawar MN Tlili A van der Zwaag B Khan SY Ayadi L Riazuddin SA Morell RJ Griffith AJ Charfedine I Caylan R Oostrik J Karaguzel A Ghorbel A Riazuddin S Friedman TB Ayadi H Kremer H 《Nature genetics》2008,40(11):1335-1340
67.
Ralph A. A. Khan 《Cellular and molecular life sciences : CMLS》1978,34(12):1598-1600
Summary The influences of dilution, storage and pH on the distribution of 99m-technetium methylene diphosphonate (99m-Tc-MDP) in bone and various soft tissues have been investigated in the rat. The results show a marked departure from normality when large dilution factors and very acidic or basic preparations are used. 相似文献
68.
R. A. A. Khan 《Cellular and molecular life sciences : CMLS》1978,34(8):1101-1102
Summary A technique is described which will allow a study of the microcirculation to a long bone such as the femur. It involves use of a silicone rubber compound (Microfil) in combination with the Spalteholz clearing technique. Preliminary results in the normal rabbit skeleton suggest that this technique can be used to study the changes in vascularity which occur under various pathological conditions. 相似文献
69.
Sucrose induction of hepatic hyperplasia in the rat 总被引:1,自引:0,他引:1
70.