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991.
Growth-inhibitory Activity and Downregulation of the Class II Tumor-suppressor Gene H-rev107 in Tumor Cell Lines and Experimental Tumors 总被引:5,自引:0,他引:5 下载免费PDF全文
992.
993.
Familial hemiplegic migraine locus on 19p13 is involved in the common forms of migraine with and without aura 总被引:10,自引:0,他引:10
Arne May Roel A. Ophoff Gisela M. Terwindt Christine Urban Ronald van Eijk Joost Haan H. Christoph Diener Dick Lindhout Rune R. Frants Lodewijk A. Sandkuijl Michel D. Ferrari 《Human genetics》1995,96(5):604-608
Migraine is a common neurological disease of two main types: migraine with aura and migraine without aura. Familial clustering suggests that genetic factors are involved in the etiology of migraine. Recently, a gene for familial hemiplegic migraine, a rare autosomal dominant subtype of migraine with aura, was mapped to chromosome 19p13. We tested the involvement of this chromosomal region in 28 unrelated families with the common forms of migraine with and without aura, by following the transmission of the highly informative marker D19S394. Sibpair analysis showed that affected sibs shared the same marker allele more frequently than expected by chance. Our findings thus also suggest the involvement of a gene on 19p13 in the etiology of the common forms of migraine. 相似文献
994.
K Edwards G Schreiber H Dryburgh J Urban A S Inglis 《European journal of biochemistry》1976,63(1):303-311
The mechanism of the biosynthesis of albumin was studied in cell suspensions from rat liver. The cells were prepared by continuous perfusion of the liver in situ with 0.05% collagenase and 0.10% hyaluronidase and incubated under conditions optimized for the incorporation of amino acids into protein. Seven minutes after starting the incubation L-[1-14C]leucine was added, followed after 25 min by a 15 or 30-min chase with an 830-fold excess of non-radioactive L-leucine. Total protein, an albumin-like protein, and albumin were isolated from samples withdrawn immediately of total protein was found to remain constant after addition of the non-radioactive L-leucine, whereas that of the albumin-like protein decreased and that of albumin increased with incubation time. The increase in albumin radioactivity accounted for the decrease in radioactivity of the albumin-like protein, suggesting that the latter is a precursor of albumin. The precursor protein differed from albumin by an oligopeptide extension at the N-terminal end. 相似文献
995.
996.
Logan E. Miller Jillian E. Urban Joel D. Stitzel 《Biomechanics and modeling in mechanobiology》2016,15(5):1201-1214
Traumatic brain injury is a leading cause of disability and injury-related death. To enhance our ability to prevent such injuries, brain response can be studied using validated finite element (FE) models. In the current study, a high-resolution, anatomically accurate FE model was developed from the International Consortium for Brain Mapping brain atlas. Due to wide variation in published brain material parameters, optimal brain properties were identified using a technique called Latin hypercube sampling, which optimized material properties against three experimental cadaver tests to achieve ideal biomechanics. Additionally, falx pretension and thickness were varied in a lateral impact variation. The atlas-based brain model (ABM) was subjected to the boundary conditions from three high-rate experimental cadaver tests with different material parameter combinations. Local displacements, determined experimentally using neutral density targets, were compared to displacements predicted by the ABM at the same locations. Error between the observed and predicted displacements was quantified using CORrelation and Analysis (CORA), an objective signal rating method that evaluates the correlation of two curves. An average CORA score was computed for each variation and maximized to identify the optimal combination of parameters. The strongest relationships between CORA and material parameters were observed for the shear parameters. Using properties obtained through the described multiobjective optimization, the ABM was validated in three impact configurations and shows good agreement with experimental data. The final model developed in this study consists of optimized brain material properties and was validated in three cadaver impacts against local brain displacement data. 相似文献
997.
Species delimitation of the white‐tailed rubythroat Calliope pectoralis complex (Aves,Muscicapidae) using an integrative taxonomic approach 下载免费PDF全文
Yang Liu Guoling Chen Qin Huang Chenxi Jia Geoff Carey Paul Leader Yun Li Fasheng Zou Xiaojun Yang Urban Olsson Per Alström 《Journal of avian biology》2016,47(6):899-910
Our knowledge of the systematics and taxonomy of Asian birds has improved much in the last two decades, and the number of recognised species has increased significantly as a result of in‐depth studies using an integrative taxonomic approach. The Sino‐Himalayan mountains harbor a high level of passerine diversity. Several allopatric or parapatric taxa that are currently treated as subspecies of polytypic species within that region are likely to deserve full species status, and thus their taxonomic status needs to be revisited. Based on analyses of multilocus data, vocalizations and morphology, we propose that the white‐tailed rubythroat Calliope pectoralis should be treated as two species, the Himalayan rubythroat C. pectoralis sensu stricto in the Tian Shan and Himalayan mountains, and the Chinese rubythroat C. tschebaiewi in the mountains of southwestern and north‐central China. According to our dating analyses based on mitochondrial loci, these two species diverged approximately 2.2 million yr ago. We further found that C. tschebaiewi was paraphyletic to C. pectoralis sensu stricto in nuclear data, which demonstrates a state of mitonuclear discordance that warrants further work. Our results suggest that geographic changes and glacial cycles in the Pleistocene may have caused allopatric divergence in the C. pectoralis complex. Our study stresses the importance of applying an integrative taxonomy approach to fully unravel the true avian diversity in the Sino‐Himalayan Mountains. 相似文献
998.
Redistribution of water via layering branches between connected parent and daughter trees in Norway spruce clonal groups 总被引:2,自引:0,他引:2
Key message
We measured sap flow and shoot water potentials in clonally connected parent and daughter trees. We found bidirectional flow patterns in branches mediating the connection between parent and daughter trees.Abstract
Layering is an important mode of vegetative reproduction at treeline, in which clonal daughter trees are formed by the rooting of lower (“layering”) branches of the parent tree. These branches mediate the connection between parent (PT) and daughter tree (DT). Here, we measured quantity and direction of sap flow in layering branches as well as PT and DT, and measured shoot water potentials in the crowns of a connected PT and DT. We found bidirectional sap flow pattern in layering branches, with the bidirectionality of the flow resulting from water potential dynamics of the parent and daughter trees varying diurnally. We found that 4.3 % of the total water transpired by the DT was supplied by the PT root system, with up to 25 % of the instantaneous daughter tree sap flow coming from the parent tree. In contrast, water provided by the daughter’s root system to the parent tree comprised only a negligible amount, less than 1 % of the parent’s entire sap flow. Additionally, after experimental excavation of part of the DT roots, layering branch flow towards the DT increased, while flows in the opposite direction almost vanished. This study showed that aboveground clonal connections can facilitate a new type of hydraulic redistribution where water is transported bidirectionally through branches. This transfer of water and nutrients is vital especially in the first years of the daughter tree but supplies considerable amounts of water even several years after the establishment of a new clonal tree.999.
Sarah Franco Vieira de Oliveira Monica Ganzinelli Rosaria Chilà Leandro Serino Marcos Euzébio Maciel Cícero de Andrade Urban Rubens Silveira de Lima Iglenir Jo?o Cavalli Daniele Generali Massimo Broggini Giovanna Damia Enilze Maria de Souza Fonseca Ribeiro 《PloS one》2016,11(1)
MTAP is a ubiquitously expressed gene important for adenine and methionine salvage. The gene is located at 9p21, a chromosome region often deleted in breast carcinomas, similar to CDKN2A, a recognized tumor suppressor gene. Several research groups have shown that MTAP acts as a tumor suppressor, and some therapeutic approaches were proposed based on a tumors´ MTAP status. We analyzed MTAP and CDKN2A gene (RT-qPCR) and protein (western-blotting) expression in seven breast cancer cell lines and evaluated their promoter methylation patterns to better characterize the contribution of these genes to breast cancer. Cytotoxicity assays with inhibitors of de novo adenine synthesis (5-FU, AZA and MTX) after MTAP gene knockdown showed an increased sensitivity, mainly to 5-FU. MTAP expression was also evaluated in two groups of samples from breast cancer patients, fresh tumors and paired normal breast tissue, and from formalin-fixed paraffin embedded (FFPE) core breast cancer samples diagnosed as Luminal-A tumors and triple negative breast tumors (TNBC). The difference of MTAP expression between fresh tumors and normal tissues was not statistically significant. However, MTAP expression was significantly higher in Luminal-A breast tumors than in TNBC, suggesting the lack of expression in more aggressive breast tumors and the possibility of using the new approaches based on MTAP status in TNBC. 相似文献
1000.
Ane Arbillaga-Etxarri Jaume Torrent-Pallicer Elena Gimeno-Santos Anael Barberan-Garcia Anna Delgado Eva Balcells Diego A. Rodríguez Jordi Vilaró Pere Vall-Casas Alfredo Irurtia Robert Rodriguez-Roisin Judith Garcia-Aymerich Urban Training? Study Group 《PloS one》2016,11(1)