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121.
1.Korean Traditional CostumeKorean costume culture was originated from culture of northern horseriding tribe, Scythai culture. In Culture of Korean traditional costume, the basic type of clothing is short jacket and trousers or short jacket, skirt, and wearing hat, Wha (boots) and Lee (deep curved and low heel shoes). It was the cloak as protecting cold and taking Po for outdoor works. We can find stripe neck park of jacket and following round line in down part of sleeve.  相似文献   
122.
Homozygotes for Huntington's disease   总被引:5,自引:0,他引:5  
Careful comparison of symptomatic individuals with normal controls has revealed the primary biochemical abnormality in many human genetic diseases, particularly recessive disorders. This strategy has proved less successful for most human disorders which are not recessive, and where a single copy of the aberrant gene has clinically significant effects even though the normal gene product is present. An alternative approach that eliminates the impediment of a normal protein in affected individuals is to study homozygotes for the mutant allele. For virtually all dominant human disorders in which homozygotes have been described, symptoms have been significantly more severe in the homozygote than in the heterozygote. Thus, these disorders do not conform to the classical definition of dominance which states that homozygotes and heterozygotes for a defect are phenotypically indistinguishable. Instead, they display incomplete dominance, indicating that the normal allele may play a role in ameliorating the disease process. The D4S10 locus, defined by the probe G8 and linked to the gene for Huntington's disease (HD), has permitted us to identify individuals with a high probability of being homozygous for this autosomal dominant neurodegenerative disorder. These homozygotes do not differ in clinical expression or course from typical HD heterozygotes. HD appears to be the first human disease of genetically documented homozygosity that displays complete phenotypic dominance.  相似文献   
123.
The basis of peripheral blood lymphopenia observed in patients with chronic alcoholism and liver disease was investigated by examining the effect of sera of these patients on in vitro transformation of normal human peripheral blood lymphocytes. A positive correlation was demonstrated between the serum inhibition of phytohaemagglutinin- and pokeweed mitogen-induced transformation and the degree of lymphopenia. Thus serum factors may contribute to the observed lymphopenia by inhibiting lymphocyte production in vivo.  相似文献   
124.
125.
Neuroblastoma in advanced stages is one of the most intractable paediatric cancers, even with recent therapeutic advances. Neuroblastoma harbours a variety of genetic changes, including a high frequency of MYCN amplification, loss of heterozygosity at 1p36 and 11q, and gain of genetic material from 17q, all of which have been implicated in the pathogenesis of neuroblastoma. However, the scarcity of reliable molecular targets has hampered the development of effective therapeutic agents targeting neuroblastoma. Here we show that the anaplastic lymphoma kinase (ALK), originally identified as a fusion kinase in a subtype of non-Hodgkin's lymphoma (NPM-ALK) and more recently in adenocarcinoma of lung (EML4-ALK), is also a frequent target of genetic alteration in advanced neuroblastoma. According to our genome-wide scans of genetic lesions in 215 primary neuroblastoma samples using high-density single-nucleotide polymorphism genotyping microarrays, the ALK locus, centromeric to the MYCN locus, was identified as a recurrent target of copy number gain and gene amplification. Furthermore, DNA sequencing of ALK revealed eight novel missense mutations in 13 out of 215 (6.1%) fresh tumours and 8 out of 24 (33%) neuroblastoma-derived cell lines. All but one mutation in the primary samples (12 out of 13) were found in stages 3-4 of the disease and were harboured in the kinase domain. The mutated kinases were autophosphorylated and displayed increased kinase activity compared with the wild-type kinase. They were able to transform NIH3T3 fibroblasts as shown by their colony formation ability in soft agar and their capacity to form tumours in nude mice. Furthermore, we demonstrate that downregulation of ALK through RNA interference suppresses proliferation of neuroblastoma cells harbouring mutated ALK. We anticipate that our findings will provide new insights into the pathogenesis of advanced neuroblastoma and that ALK-specific kinase inhibitors might improve its clinical outcome.  相似文献   
126.
Choanoflagellates are the closest known relatives of metazoans. To discover potential molecular mechanisms underlying the evolution of metazoan multicellularity, we sequenced and analysed the genome of the unicellular choanoflagellate Monosiga brevicollis. The genome contains approximately 9,200 intron-rich genes, including a number that encode cell adhesion and signalling protein domains that are otherwise restricted to metazoans. Here we show that the physical linkages among protein domains often differ between M. brevicollis and metazoans, suggesting that abundant domain shuffling followed the separation of the choanoflagellate and metazoan lineages. The completion of the M. brevicollis genome allows us to reconstruct with increasing resolution the genomic changes that accompanied the origin of metazoans.  相似文献   
127.
The death of massive stars produces a variety of supernovae, which are linked to the structure of the exploding stars. The detection of several precursor stars of type II supernovae has been reported (see, for example, ref. 3), but we do not yet have direct information on the progenitors of the hydrogen-deficient type Ib and Ic supernovae. Here we report that the peculiar type Ib supernova SN 2006jc is spatially coincident with a bright optical transient that occurred in 2004. Spectroscopic and photometric monitoring of the supernova leads us to suggest that the progenitor was a carbon-oxygen Wolf-Rayet star embedded within a helium-rich circumstellar medium. There are different possible explanations for this pre-explosion transient. It appears similar to the giant outbursts of luminous blue variable stars (LBVs) of 60-100 solar masses, but the progenitor of SN 2006jc was helium- and hydrogen-deficient (unlike LBVs). An LBV-like outburst of a Wolf-Rayet star could be invoked, but this would be the first observational evidence of such a phenomenon. Alternatively, a massive binary system composed of an LBV that erupted in 2004, and a Wolf-Rayet star exploding as SN 2006jc, could explain the observations.  相似文献   
128.
Koenigs M  Young L  Adolphs R  Tranel D  Cushman F  Hauser M  Damasio A 《Nature》2007,446(7138):908-911
The psychological and neurobiological processes underlying moral judgement have been the focus of many recent empirical studies. Of central interest is whether emotions play a causal role in moral judgement, and, in parallel, how emotion-related areas of the brain contribute to moral judgement. Here we show that six patients with focal bilateral damage to the ventromedial prefrontal cortex (VMPC), a brain region necessary for the normal generation of emotions and, in particular, social emotions, produce an abnormally 'utilitarian' pattern of judgements on moral dilemmas that pit compelling considerations of aggregate welfare against highly emotionally aversive behaviours (for example, having to sacrifice one person's life to save a number of other lives). In contrast, the VMPC patients' judgements were normal in other classes of moral dilemmas. These findings indicate that, for a selective set of moral dilemmas, the VMPC is critical for normal judgements of right and wrong. The findings support a necessary role for emotion in the generation of those judgements.  相似文献   
129.
以宁夏盐池县本地苜蓿XM及宁夏益科农业科技有限公司引进的15个美国紫花苜蓿品种为研究对象,综合考虑生育期、株高、密度、产草量、茎叶比、越冬率等指标,开展苜蓿引种适应性研究.结果表明,以本地种XM为对照,15个外引种紫花苜蓿在生长发育特性上存在显著差异.其中,以品种ZHM,E3006,D4,D2表现较优,其返青早,青绿期长,鲜草产量分别是对照的1.52,1.45,1.28,1.25倍,干草产量分别是对照的1.46,1.25,1.22,1.19倍,且抗旱性强,品质优良,适宜在宁夏盐池县等中部干旱带大面积推广应用.  相似文献   
130.
Young S 《Nature》2012,483(7387):18-19
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