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81.
Silviene Fabiana De Oliveira Eliane Barbosa Dos Santos Patrícia Jeanne De Souza Mendona Daniela Cristiane Da Cruz Rocha Sidney Emanuel Batista Dos Santos 《American journal of human biology》2001,13(6):718-720
The group‐specific component (GC) system is of interest in anthropological genetic studies because the distribution of its subtypes distinguishes among major ethnic groups. The GC system was analyzed in Curiaú and Pacoval, two remnant Quilombo populations (African‐derived populations) from the Brazilian Amazon. There was no significant statistical difference in allelic frequencies between the two populations or between them and three other African‐derived Brazilian populations (Mimbó, Sítio Velho, and Gaucinha in Northeastern Brazil). These populations share similarities among themselves and with African populations (high frequencies of GC*1F and lower frequencies of GC*1S), which may reflect the influence of a high level of African contribution to their formation, but there is a clear difference between them and Europeans and South American Indians. It is suggested that the GC system is a useful marker for studying relationships between single populations and major ethnic groups, but does not discriminate between populations which share the same parental stock. Am. J. Hum. Biol. 13:718–720, 2001. © 2001 Wiley‐Liss, Inc. 相似文献
82.
Age-dependent and iron-independent expression of two mRNA isoforms of divalent metal transporter 1 in rat brain 总被引:12,自引:0,他引:12
Ke Y Chang YZ Duan XL Du JR Zhu L Wang K Yang XD Ho KP Qian ZM 《Neurobiology of aging》2005,26(5):739-748
The DMT1(Nramp2/DCT1) is a newly discovered proton-coupled metal-ion transport protein. The cellular localization and functional characterization of DMT1 suggest that it might play a role in physiological iron transport in the brain. In the study, we evaluated effects of dietary iron and age on iron content and DMT1 expression in four brain regions: cortex, hippocampus, striatum, substantia nigra. Total iron content in all regions was significantly lower in the low-iron diet rats and higher in the high-iron diet rats than that in the control animals, showing that dietary iron treatment for 6-weeks can alter brain iron levels. Contrary to our expectation, there was no significant alternation in DMT1(+IRE) and (-IRE) mRNA expression and protein content in all brain regions examined in spite of the existence of the altered iron levels in these regions after 6-weeks' diet treatment although TfR mRNA expression and protein level were affected significantly, as was expected. The data demonstrates that expression of DMT1(+IRE) and (-IRE) was not regulated by iron in these regions of adult rats. The lack of response of DMT1 to iron status in the brain suggests that the IRE of brain DMT1 mRNA might be not really iron-responsive and that DMT1-mediated iron transport might be not the rate-limiting step in brain iron uptake in adult rats. Our findings also showed that development can significantly affect brain iron and DMT1(+IRE) and (-IRE) expression but the effect varies in different brain regions, indicating a regionally specific regulation in the brain. 相似文献
83.
M-R. Verschraegen-Spae H. Dapypare F. Spalaman M. Dhondt A. Da Paepe 《Clinical genetics》1992,41(4):218-220
A 28-year-old Turner female with secondary amenorrhea is described, who showed 45,X/46,X,del(Xp) mosaicism in her blood lymphocytes and a 46,X,del(Xp) karyotype only in her ovaries. 45,X/46,XX mosaicism was found in the patient's mother, who presented short stature, mild Turner dysmorphism and had a normal reproductive life-span. Phenotypic implications of the cytogenetic findings in the patients are discussed, and literature data on fertility in Turner syndrome are briefly reviewed. 相似文献
84.
Burzynski GM Nolte IM Osinga J Ceccherini I Twigt B Maas S Brooks A Verheij J Plaza Menacho I Buys CH Hofstra RM 《European journal of human genetics : EJHG》2004,12(8):604-612
Hirschsprung disease (HSCR), a congenital disorder characterized by intestinal obstruction due to absence of enteric ganglia along variable lengths of the intestinal tract, occurs both in familial and sporadic cases. RET mutations have been found in approximately 50% of the families, but explains only a minority of sporadic cases. This study aims at investigating a possible role of RET in sporadic HSCR patients. Haplotypes of 13 DNA markers, within and flanking RET, have been determined for 117 sporadic HSCR patients and their parents. Strong association was observed for six markers in the 5' region of RET. The largest distortions in allele transmission were found at the same markers. One single haplotype composed of these six markers was present in 55.6% of patients versus 16.2% of controls. Odds ratios (ORs) revealed a highly increased risk of homozygotes for this haplotype to develop HSCR (OR>20). These results allowed us to conclude that RET plays a crucial role in HSCR even when no RET mutations are found. An unknown functional disease variant(s) with a dosage-dependent effect in HSCR is likely located between the promoter region and exon 2 of RET. 相似文献
85.
Both Human Immunodeficiency Virus Cellular DNA Sequencing and Plasma RNA Sequencing Are Useful for Detection of Drug Resistance Mutations in Blood Samples from Antiretroviral-Drug-Naive Patients
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86.
Pierre Marschall Ruicheng Wei Justine Segaud Wenjin Yao Pierre Hener Beatriz Falcon German Pierre Meyer Cecile Hugel Grace Ada Da Silva Reinhard Braun Daniel H. Kaplan Mei Li 《The Journal of allergy and clinical immunology》2021,147(5):1778-1794
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87.
88.
肺神经内分泌癌的免疫组化与免疫电镜研究 总被引:3,自引:1,他引:3
本文应用免疫组化与免疫电镜技术对20例肺神经内分泌癌进行了研究,另6例非神经内分泌癌作为对照。结果表明:嗜铬颗粒蛋白A免疫组化染色19/20例阳性,免疫电镜能够比较特异地标记神经分泌颗粒,具有确诊意义;神经特异性烯醇化酶染色20/20例阳性,非神经内分泌癌3/6例阳性,免疫电镜下无特异性分布,适宜作为诊断的筛选指标;S-100蛋白和5-HT亦可作为诊断之参考。 相似文献
89.
90.