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921.
922.
Erich Roessler Kenia B. El‐Jaick Christèle Dubourg Jorge I. Vélez Benjamin D. Solomon Daniel E. Pineda‐álvarez Felicitas Lacbawan Nan Zhou Maia Ouspenskaia Aimée Paulussen Hubert J. Smeets Ute Hehr Claude Bendavid Sherri Bale Sylvie Odent Véronique David Maximilian Muenke 《Human mutation》2009,30(10):E921-E935
Mutations within either the SHH gene or its related pathway components are the most common, and best understood, pathogenetic changes observed in holoprosencephaly patients; this fact is consistent with the essential functions of this gene during forebrain development and patterning. Here we summarize the nature and types of deleterious sequence alterations among over one hundred distinct mutations in the SHH gene (64 novel mutations) and compare these to over a dozen mutations in disease‐related Hedgehog family members IHH and DHH. This combined structural analysis suggests that dysfunction of Hedgehog signaling in human forebrain development can occur through truncations or major structural changes to the signaling domain, SHH‐N, as well as due to defects in the processing of the mature ligand from its pre‐pro‐precursor or defective post‐translation bi‐lipid modifications with palmitate and cholesterol Published 2009 by Wiley‐Liss, Inc. 相似文献
923.
Renal Interlobar Vein Impedance Index as a First‐Trimester Marker Does Not Predict Hypertensive Disorders of Pregnancy 下载免费PDF全文
924.
925.
Ilka Maria Vasconcelos Fernanda Maria Machado Maia Davi Felipe Farias Claudio Cabral Campello Ana Fontenele Urano Carvalho Renato de Azevedo Moreira Jose Tadeu Abreu de Oliveira 《Journal of food composition and analysis》2010,23(1):54-60
High-yielding cowpea (Vigna unguiculata) cultivars were analysed for major changes in seed protein types, amino acid profiles and antinutritional factors content. As usual, the globulins constitute the major seed proteins (493.2–573.3 g kg?1 total seed protein), followed by albumins (201.0–248.0 g kg?1), basic glutelins (119.1–154.3 g kg?1), acid glutelins (82.4–92.3 g kg?1) and prolamins (13.2–20.2 g kg?1). The electrophoretic patterns of seeds and protein fractions for all cowpea cultivars resembled to each other both qualitatively and quantitatively. However, they showed slight differences in the amino acid composition with common prevalence of glutamine/glutamic acid, asparagine/aspartic acid and phenylalanine + tyrosine. The methionine + cysteine contents were low for all cultivars and their protein fractions. Trypsin inhibitory activity varied among the cultivars and was much higher in the albumins (198.67–393.43 g kg?1 protein). Haemagglutinating activity was also higher in the albumin fraction and varied from 30,900 to 444,400 HU kg?1 flour. In conclusion, all cultivars showed the usual compositional characteristics of V. unguiculata, but the content of antinutritional factors differed among the cultivars although they remained concentrated in albumin and globulin fractions. 相似文献
926.
Socio-economic status, growth, physical activity and fitness: the Madeira Growth Study 总被引:2,自引:0,他引:2
Freitas D Maia J Beunen G Claessens A Thomis M Marques A Crespo M Lefevre J 《Annals of human biology》2007,34(1):107-122
BACKGROUND: Within a country social conditions change over time and these conditions vary from country to country. The associations between these conditions, somatic growth, physical activity and fitness reflect these changes. AIM: The study documented variation in somatic growth, physical activity and fitness associated with socio-economic status (SES). SUBJECTS AND METHODS: The study involved 507 subjects (256 boys and 251 girls) from the Madeira Growth Study, a mixed longitudinal study of five cohorts (8, 10, 12, 14 and 16 years of age) followed at yearly intervals over 3 years (1996-1998). A total of 1493 observations were made. Anthropometric measurements included lengths, body mass, skeletal breadths, girths and skinfolds. Physical activity and SES were collected via questionnaire and interview. Physical fitness was assessed using the Eurofit test battery. Variation in somatic growth, physical activity and physical fitness by SES (high, average and low) was tested with analysis of variance. RESULTS: Significant differences between SES groups were observed for height, body mass and skinfolds. Boys and girls from high SES groups were taller, heavier and fatter (subscapular and triceps skinfolds) than their peers from average and low SES groups. At some age intervals, the high SES group had larger skeletal breadths (girls) and girths (boys and girls) than low SES. Small SES differences were observed for physical activity (sport and leisure-time indices). SES was significantly associated with physical fitness. At some age levels, boys from the low SES group performed better for muscular and aerobic endurance whereas girls from the high SES group performed better for power. CONCLUSION: Considerable variation in somatic growth and physical fitness in association with SES has been demonstrated, but little association was found for physical activity. 相似文献
927.
Objective
To investigate if body mass index (BMI) is related to inflammatory markers and hormones in early pregnancy. 相似文献928.
The population of Costa Rica has been considered valuable for locating susceptibility genes of complex disorders because of historical events and a gradual admixture process. We present an assessment of 426 unrelated individuals with a familial history of mental disorder and with ancestors born in the Central Valley, genotyped at 730 microsatellites to evaluate genetic diversity, ancestry, and substructure at the general and regional population levels using quantitative methods. Low population substructure was found. Estimated mean ancestry proportions were 54%, 32%, and 13% for European, Amerindian, and African components, respectively, with some regional variation. The F(ST) values obtained confirm the largest genetic similarity to Europeans. Subdivision of the Amerindians into individual populations revealed strong similarity to Chibchan groups. Analysis of the African ancestry showed high similarity to West and Central African populations. Gene ancestries from other African areas were also detected, probably resulting from ancestral admixture within Africa prior to colonial times. Our analyses show, in an ethnohistorical-genetic context, that gene flow and admixture are important components of Costa Rican population history. The results confirm the need to consider the particular regional genetic structure, the effects of genetic drift and the ancestry when designing and interpreting investigations of genetic traits in this population. 相似文献
929.
Theresa Diaz Maria de Gloria Bonecini Almeida Ingebourg Georg Suely de Carvalho Maia Rogerio Valls de Souza Lauri E. Markowitz 《Clinical and Vaccine Immunology : CVI》2004,11(1):98-101
The Abbott Determine Rapid Syphilis TP assay is a treponemal test that can be used in resource-poor settings that lack laboratory facilities. However, this test has not been extensively evaluated. We measured its sensitivity and specificity by using stored serum specimens (n = 567) from all persons who tested Treponema pallidum hemagglutination assay (TPHA) positive (n = 250) or TPHA indeterminate (n = 17) in the year 2001 and the first 300 patients in 2001 who tested TPHA negative at the Evandro Chagas Research Institute in Rio de Janeiro, Brazil. This rapid assay was independently interpreted by three different observers. With TPHA results as the reference, sensitivity ranged between readers from 95.6 to 98.4% and specificity ranged from 97.3 to 95.7%. There was little interreader variability in the interpretation of results, with approximately 98% agreement for all reader combinations. Of samples from persons with human immunodeficiency virus (HIV) infection (n = 198), sensitivity was 96.9 to 99.2% and it was 94.4 to 96.3% among HIV-negative persons (n = 127). Specificity was 92.4 to 95.5% among HIV-positive persons and 97.2 to 100% among HIV-negative persons. We found this test to have high sensitivity and specificity and little interreader variability, indicating that it may be easily used in resource-poor settings without laboratory facilities. Further studies are needed using this test on whole blood and under the clinical conditions for which it is intended. 相似文献
930.
Sylvia Lopes Maia Teixeira Francisco Inácio Bastos Paulo Roberto Telles Mariana A Hacker Luis F Brigido Carmem Aparecida de F Oliveira Vera Bongertz Mariza Gon?alves Morgado 《Journal of clinical virology》2004,31(3):221-226
BACKGROUND AND OBJECTIVES: Due to their behavioral conditions and vulnerability, injection drug users (IDUs) are prone to multiple simultaneous or sequential infections with distinct HIV-1 subtypes and variants, making them a key population for molecular epidemiology surveillance. In the present study, we evaluated HIV-1 infection seroprevalence, genetic diversity and estimated incidence among IDUs and ex-injection drug users (ex-IDUs) from Rio de Janeiro, Brazil. STUDY DESIGN: Six hundred and eight IDUs and ex-IDUs, recruited between 1999 and 2001, were interviewed and agreed to donate 30 ml of blood. The serologic status for HIV infection was determined by two ELISAs and confirmed by IFA. CD4+ T-cell percentages were assessed by flow cytometry. HIV-1 positive samples were submitted to viral load quantification. DNA samples were PCR amplified and HIV-1 subtypes were determined using env and gag HMA. RESULTS AND CONCLUSIONS: Forty-eight (7.89%) individuals were seropositive for HIV-1 infection. The seroincidence of HIV-1 infection was estimated as 0.76%. HIV-1 env and gag subtyping identified 29 (69%) samples as belonging to subtype B, 7 (16.7%) to subtype F, and 6 (14.3%) discordant env/gag genomes infections, indicating the circulation of recombinant viruses in this population. 相似文献