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排序方式: 共有340条查询结果,搜索用时 15 毫秒
121.
Mehmet Kü?ükaycan Michiel Van Krugten Herman-Jan Pennings Tom WJ Huizinga Wim A Buurman Mieke A Dentener Emiel FM Wouters 《Respiratory research》2002,3(1):29
Background
Chronic obstructive pulmonary disease (COPD) is characterized by a chronic inflammatory process, in which the pro-inflammatory cytokine Tumor Necrosis Factor (TNF)-α is considered to play a role. In the present study the putative involvement of TNF-α gene polymorphisms in pathogenesis of COPD was studied by analysis of four TNF-α gene polymorphisms in a Caucasian COPD population. 相似文献122.
123.
Summary A new G6PD variant, designated Gd (+) Laguna, was found in a 9-year-old Brazillian boy of Portuguese ancestry suffering from an iron-refractory anemia. The red cell enzyme activity of the subject was 64%. The mutant enzyme showed slower electrophoretic mobility, increased affinity for glucose-6-phosphate, decreased affinity for NADP+, elevated utilization of substrate analogues, decreased inhibition of NADPH, normal heat stability and a biphasic pH curve. The occurrence of the variant in two non-anemic relatives of the propositus indicates that the association between this G6PD type and anemia may be coincidental.Publication no. 3171 BCR from the Research Institute of Scripps Clinic 相似文献
124.
H Schneider M I Sampaio M P Schneider J M Ayres C M Barroso A R Hamel B T Silva F M Salzano 《American journal of physical anthropology》1991,85(1):85-93
A comparative study of 13 blood genetic systems and pelage color variation was performed in four wild populations of Alouatta belzebul. The animals from the west bank of the Tocantins River showed less color variation than those from the east bank, as well as less than those from Tocantins Island. The blood genetic markers, however, revealed an opposite pattern of variation. A previously undescribed morphological variant (completely red) was observed in one specimen of the east bank, where pelage color of the local population varied from completely black to completely red. Levels of heterozygosity and inter- and intralocus variances for the blood systems are compared with those observed in five other species of New World primates. 相似文献
125.
M. Helena L. P. Franco Tania A. Weimer F. M. Salzano 《American journal of physical anthropology》1982,58(2):127-132
One thousand individuals from the southern population of Porto Alegre and 760 from the northeastern city of Natal were studied in relation to 12 and 8 genetic systems, respectively. The data thus gathered were used in different ways to estimate quantitatively the ethnic composition of individuals from these communities. More than half of the genes present in individuals classified as Black in Porto Alegre may be of White origin, while the Whites from this city have 8% of African alleles. The estimated degree of admixture in persons identified as White or Mixed in Natal is not much different among themselves. The ancestry of the total sample can be characterized as 58% White, 25% Black, and 17% Indian. 相似文献
126.
F. M. Salzano S.M. Callegari Jacques M.H.L.P. Franco M. H. Hutz T. A. Weimer R. S. Silva F. J. Da Rocha 《American journal of physical anthropology》1980,53(4):513-524
A total of 248 individuals belonging to four populations of Caingang Indians from southern Brazil were stuided in relation to 23 genetic systems that are expressed in blood and one manifested on saliva. These results were compared with those obtained in 400 members of these same communities that were subjected to 11 body measurements. Nine polymorphic loci (MNSs, P, Rh, Duffy, Diego, Hp, PGM1, ESD, and Gc) were chosen for the calculation of the genetic distances between the four populations, which were compared with Mahalanobis's D2 differences. The two sets of values proved to be intercorrelated but neither showed a relationship with the geographic distances separating the four communities. The Caingang were previously classified linguistically as Gê, and they show several affinities with the Gê tribes, both when hematological, and morphological, characteristics are considered. A variant PGD phenotype is also described, showing a curious storage effect. 相似文献
127.
Francis L. Black Francisco M. Salzano Zulay Layrisse M. Helena L. P. Franco Nancy S. Harris Tania A. Weimer 《American journal of physical anthropology》1980,52(1):119-132
Results concerning HLA types and 22 other blood genetic systems are reported for the Parakanã Indians of northern Brazil, a tribe that is notable for the light color and pilosity of some of its members. No clear evidence of Caucasoid admixture was found, but the Parkanã show unusual frequencies in the EsD1, PGM11, Gc2, CpB, Fya, Dia, and LM genetic markers. In addition, the very rare Rh allele ry is present, as well as what seems to be a new PGM2 variant. There is very limited heterogeneity in the HLA system. All these distinctive features may have arisen through a combination of founder effects and genetic drift. However, low Fis values, as well as higher mean ages in heterozygous as compared to homozygous persons, suggest that an heterotic effect is counteracting these dispersive forces. 相似文献
128.
The number of persons with homozygous HLA haplotypes in several groups of South American Indians was 39% less than that expected assuming unmodified equilibrium. In a subpopulation of 122 persons whose parents' HLA constitutions were known, there were 56% fewer homozygous persons than expected. This deficit was widely distributed in different haplotypes and different tribal groups. 相似文献
129.
130.
Summary 46 individuals, ascertained due to gonadal dysgenesis symptoms, were studied. 16 of them were 45, X and showed characteristics of Turner's syndrome. 15 proved to be chromosome mosaics and presented Turner's syndrome (12 cases), mixed gonadal dysgenesis (2) and gonadoblastoma (1). There were also 2 cases of pure gonadal dysgenesis and 13 patients with normal karyotypes. The clinical and genealogical data obtained from these individuals and their families were compared with 26 other series reported in the literature. Common malformations besides those related to sexual development are: short stature, abnormal nails, low implantation of hair, pigmented naevi, shield chest, short neck and cubitus valgus. Persons with 45,X karyotypes generally presented a more severe clinical picture than mosaics. The prevalence of twins is higher than expected among the patients' sibs in the cases reported here and in 3 of the 5 other series for which data are available.
Née Suñé. 相似文献
Zusammenfassung 46 Personen mit Symptomen der Gonadendysgenesie wurden untersucht. 16 von ihnen waren 45,XO und zeigten Symptome des Turner-Syndroms. 15 erwiesen sich als Chromosomenmosaiken; 12 von ihnen zeigten ebenfalls das Turner-Syndrom, 2 zeigten eine gemischte Gonadendysgenesie, während 1 Patient ein Gonadoblastom aufwies. Außerdem wurden 2 Fälle von einer Gonadendysgenesie und 13 Patienten mit normalem Karyotyp beobachtet. Die klinischen und genealogischen Daten von diesen Patienten und ihren Familien wurden mit denen aus 26 Literaturserien verglichen. Außer den Störungen der sexuellen Entwicklung sind die folgenden Mißbildungen häufig: Kleinwuchs, abnorme Nägel, niedrige Haargrenze, Pigmentnaevi, schildförmiger Torax, kurzer Hals, Cubitus valgus. Im allgemeinen zeigen Personen mit 45,XO-Karyotypen ein schwereres klinisches Bild als Mosaiken. Unter den Geschwistern der Patienten finden sich Zwillinge häufiger als erwartet; das gilt auch für 3 der 5 anderen Serien, für die Daten verfügbar sind.
Née Suñé. 相似文献