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51.
文章从专业翻译角度讨论了翻译和术语的关系,分析译者面临的术语问题以及解决这类问题最合适的策略和资源。在此基础上,提出译者在术语工作上不同程度的参与方式。  相似文献   
52.
Most common human traits and diseases have a polygenic pattern of inheritance: DNA sequence variants at many genetic loci influence the phenotype. Genome-wide association (GWA) studies have identified more than 600 variants associated with human traits, but these typically explain small fractions of phenotypic variation, raising questions about the use of further studies. Here, using 183,727 individuals, we show that hundreds of genetic variants, in at least 180 loci, influence adult height, a highly heritable and classic polygenic trait. The large number of loci reveals patterns with important implications for genetic studies of common human diseases and traits. First, the 180 loci are not random, but instead are enriched for genes that are connected in biological pathways (P = 0.016) and that underlie skeletal growth defects (P?相似文献   
53.
Ulcerative colitis, a chronic inflammatory disease of the colon, is associated with a high risk of colorectal carcinoma that is thought to develop through genomic instability. We considered that the rapid cell turnover and oxidative injury observed in ulcerative colitis might accelerate telomere shortening, thereby increasing the potential of chromosomal ends to fuse, resulting in cycles of chromatin bridge breakage and fusion and chromosomal instability associated with tumor cell progression. Here we have used quantitative fluorescence in situ hybridization to compare chromosomal aberrations and telomere shortening in non-dysplastic mucosa taken from individuals affected by ulcerative colitis, either with (UC progressors) or without (UC non-progressors) dysplasia or cancer. Losses, but not gains, of chromosomal arms and centromeres are highly correlated with telomere shortening. Chromosomal losses are greater and telomeres are shorter in biopsy samples from UC progressors than in those from UC non-progressors or control individuals without ulcerative colitis. A mechanistic link between telomere shortening and chromosomal instability is supported by a higher frequency of anaphase bridges--an intermediate in the breakage and fusion of chromatin bridges--in UC progressors than in UC non-progressors or control individuals. Our study shows that telomere length is correlated with chromosomal instability in a precursor of human cancer.  相似文献   
54.
Resumen Se inmunizaron ratones BALB con glóbulos rojos de ratas de una línea endocriada. A estos ratones se les extrajo el ARN del bazo y se inyectó a otro grupo de animales de la misma cepa. Además, se inyectó el ARN proveniente de bazo de ratón normal a un segundo grupo de animales. Cinco días después de la inyección del ARN normal e inmune, ambos grupos, y un tercero, testigo, recibieron una inyección de glóbulos rojos de rata.  相似文献   
55.
Transcriptome analysis of the acoelomate human parasite Schistosoma mansoni   总被引:1,自引:0,他引:1  
Schistosoma mansoni is the primary causative agent of schistosomiasis, which affects 200 million individuals in 74 countries. We generated 163,000 expressed-sequence tags (ESTs) from normalized cDNA libraries from six selected developmental stages of the parasite, resulting in 31,000 assembled sequences and 92% sampling of an estimated 14,000 gene complement. By analyzing automated Gene Ontology assignments, we provide a detailed view of important S. mansoni biological systems, including characterization of metazoa-specific and eukarya-conserved genes. Phylogenetic analysis suggests an early divergence from other metazoa. The data set provides insights into the molecular mechanisms of tissue organization, development, signaling, sexual dimorphism, host interactions and immune evasion and identifies novel proteins to be investigated as vaccine candidates and potential drug targets.  相似文献   
56.
A progeroid syndrome in mice is caused by defects in A-type lamins   总被引:21,自引:0,他引:21  
Mounkes LC  Kozlov S  Hernandez L  Sullivan T  Stewart CL 《Nature》2003,423(6937):298-301
Numerous studies of the underlying causes of ageing have been attempted by examining diseases associated with premature ageing, such as Werner's syndrome and Hutchinson-Gilford progeria syndrome (HGPS). HGPS is a rare genetic disorder resulting in phenotypes suggestive of accelerated ageing, including shortened stature, craniofacial disproportion, very thin skin, alopecia and osteoporosis, with death in the early teens predominantly due to atherosclerosis. However, recent reports suggest that developmental abnormalities may also be important in HGPS. Here we describe the derivation of mice carrying an autosomal recessive mutation in the lamin A gene (Lmna) encoding A-type lamins, major components of the nuclear lamina. Homozygous mice display defects consistent with HGPS, including a marked reduction in growth rate and death by 4 weeks of age. Pathologies in bone, muscle and skin are also consistent with progeria. The Lmna mutation resulted in nuclear morphology defects and decreased lifespan of homozygous fibroblasts, suggesting premature cell death. Here we present a mouse model for progeria that may elucidate mechanisms of ageing and development in certain tissue types, especially those developing from the mesenchymal cell lineage.  相似文献   
57.
Summary The salivary secretion ofRhodnius prolixus inhibits both ADP and collagen induced platelet aggregation in human platelet-rich plasma. Fractionation studies show that at least 3 different inhibitors are present inRhodnius saliva.  相似文献   
58.
The outbreak of Dutch elm disease in the 1970s ravaged European elm populations, killing more than 25 million trees in Britain alone; the greatest impact was on Ulmus procera, otherwise known as the English elm. Here we use molecular and historical information to show that this elm derives from a single clone that the Romans transported from Italy to the Iberian peninsula, and from there to Britain, for the purpose of supporting and training vines. Its highly efficient vegetative reproduction and its inability to set seeds have preserved this clone unaltered for 2,000 years as the core of the English elm population--and the preponderance of this susceptible variety may have favoured a rapid spread of the disease.  相似文献   
59.
60.
The Drosophila Hsp67Bc gene encodes a protein belonging to the small heat-shock protein (sHSP) family, identified as the nearest functional ortholog of human HSPB8. The most prominent activity of sHSPs is preventing the irreversible aggregation of various non-native polypeptides. Moreover, they are involved in processes such as development, aging, maintenance of the cytoskeletal architecture and autophagy. In larval muscles Hsp67Bc localizes to the Z- and A-bands, which suggests its role as part of the conserved chaperone complex required for Z-disk maintenance. In addition, Hsp67Bc is present at neuromuscular junctions (NMJs), which implies its involvement in the maintenance of NMJ structure. Here, we report the effects of muscle-target overexpression of Drosophila Hsp67Bc hot-spot variants Hsp67BcR126E and Hsp67BcR126N mimicking pathogenic variants of human HSPB8. Depending on the substitutions, we observed a different impact on muscle structure and performance. Expression of Hsp67BcR126E affects larval motility, which may be caused by impairment of mitochondrial respiratory function and/or by NMJ abnormalities manifested by a decrease in the number of synaptic boutons. In contrast, Hsp67BcR126N appears to be an aggregate-prone variant, as reflected in excessive accumulation of mutant proteins and the formation of large aggregates with a lesser impact on muscle structure and performance compared to the Hsp67BcR126E variant.  相似文献   
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