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151.
Chien-Yuan Tseng Houng-Yi Yang WAN Yusheng LIU Dunyi Da-Jen Wen Tzung-Chi Lin Kuo-An Tung 《科学通报(英文版)》2006,51(8):963-970
The Qilian Mountain is considered a part of the Cen- tral Orogenic Belt of China[1]. The Central Orogenic Belt of China, extending for a distance of about 4000 km long in the E-W direction from the east coast west- ward through the mainland China all the … 相似文献
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Planning for smallpox outbreaks 总被引:1,自引:0,他引:1
Ferguson NM Keeling MJ Edmunds WJ Gani R Grenfell BT Anderson RM Leach S 《Nature》2003,425(6959):681-685
Mathematical models of viral transmission and control are important tools for assessing the threat posed by deliberate release of the smallpox virus and the best means of containing an outbreak. Models must balance biological realism against limitations of knowledge, and uncertainties need to be accurately communicated to policy-makers. Smallpox poses the particular challenge that key biological, social and spatial factors affecting disease spread in contemporary populations must be elucidated largely from historical studies undertaken before disease eradication in 1979. We review the use of models in smallpox planning within the broader epidemiological context set by recent outbreaks of both novel and re-emerging pathogens. 相似文献
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Deletion of brain dystroglycan recapitulates aspects of congenital muscular dystrophy 总被引:20,自引:0,他引:20
Moore SA Saito F Chen J Michele DE Henry MD Messing A Cohn RD Ross-Barta SE Westra S Williamson RA Hoshi T Campbell KP 《Nature》2002,418(6896):422-425
Fukuyama congenital muscular dystrophy (FCMD), muscle-eye-brain disease (MEB), and Walker-Warburg syndrome are congenital muscular dystrophies (CMDs) with associated developmental brain defects. Mutations reported in genes of FCMD and MEB patients suggest that the genes may be involved in protein glycosylation. Dystroglycan is a highly glycosylated component of the muscle dystrophin-glycoprotein complex that is also expressed in brain, where its function is unknown. Here we show that brain-selective deletion of dystroglycan in mice is sufficient to cause CMD-like brain malformations, including disarray of cerebral cortical layering, fusion of cerebral hemispheres and cerebellar folia, and aberrant migration of granule cells. Dystroglycan-null brain loses its high-affinity binding to the extracellular matrix protein laminin, and shows discontinuities in the pial surface basal lamina (glia limitans) that probably underlie the neuronal migration errors. Furthermore, mutant mice have severely blunted hippocampal long-term potentiation with electrophysiologic characterization indicating that dystroglycan might have a postsynaptic role in learning and memory. Our data strongly support the hypothesis that defects in dystroglycan are central to the pathogenesis of structural and functional brain abnormalities seen in CMD. 相似文献
157.
Smallwood S 《Population trends》2002,(108):32-48
A greater understanding of past, present and future trends in fertility can be gained from analysing trends in birth order; that is whether a birth is a first, second, third or higher order birth. However, under current legislation, birth order information is not collected at registration for births outside marriage and birth order recorded within marriage is not the true birth order. This article presents revised and updated estimates of true birth order. It discusses the construction of the new estimates and presents analysis relating the births by true birth order to the population of women by parity on both a period (fertility in a particular year) and cohort (fertility of women born in a particular year) basis. The new true birth order figures are also compared to the previous set of estimates. 相似文献
158.
Change is now a constant feature of organizational life, but the effectiveness of change management initiatives is often open to question. By reflecting on a case of change management involving a Higher Education Institution (HEI), this paper argues that, to be more effective, organizational change must be managed systemically. The paper first provides a systemic conceptual underpinning to change management, and then examines the case by comparing what had really happened with what might have happened if organizational change had been managed systemically. The analysis helps build an improved understanding of change management, and provides implications for future change management practice. 相似文献
159.
SHAN XuFeng WU LiZhu ZHANG LiPing TUNG ChenHo 《科学通报(英文版)》2007,52(11):1581-1584
A chiral complex of (R,R)-Pd was prepared by reaction of optically pure (R,R)-bis(pyrrol-2-ylmethyl-eneamino) cyclohexane ligand with Pd(OAc)2·2H2O under the base condition at room temperature. The weak intermolecular C-H···Pd interaction was found to be responsible for the homochiral M helix for-mation of the neutral,chiral,mononuclear (R,R)-Pd in the crystal packing. 相似文献
160.
cDNA芯片技术和病毒感染的基因表达 总被引:9,自引:0,他引:9
论述了最近发展的cDNA芯片技术及其在基因的发现和表达以及在疾病诊断上的应用。该技术是把cDNA的阵列由高速自动控制仪器置于玻璃片上,用标记的探针测定互补结合的情况,可同时进行大量基因的表达和基因的发现研究。这是一个高效率和大规模的基因组分析和表达的研究技术。使用这一新技术,发现了HIV感染期间hsp70基因表达发生的变化,传统的Northern分析证实了芯片的测定结果。综述中还包括了作者未作发表 相似文献