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201.
Rute ST Martins Laurence AM Deloffre Constantinos C Mylonas Deborah M Power Adelino VM Canário 《Reproductive biology and endocrinology : RB&E》2007,5(1):19
Background
DAX1 (NR0B1), a member of the nuclear receptors super family, has been shown to be involved in the genetic sex determination and in gonadal differentiation in several vertebrate species. In the aquaculture fish European sea bass, Dicentrarchus labrax, and in the generality of fish species, the mechanisms of sex determination and differentiation have not been elucidated. The present study aimed at characterizing the European DAX1 gene and its developmental expression at the mRNA level. 相似文献202.
Killer immunoglobulin‐like receptor repertoire analysis in a Caucasian Spanish cohort with inflammatory bowel disease 下载免费PDF全文
Ruth López‐Hernández Jose A. Campillo Isabel Legaz Mariano Valdés Hortensia Salama Francisco Boix AM Hernández‐Martínez Jorge Eguia G González‐Martínez Maria R. Moya‐Quiles Alfredo Minguela Ana García‐Alonso Fernando Carballo Manuel Muro 《Microbiology and immunology》2016,60(11):787-792
Immunological molecules are implicated in inflammatory disorders, including inflammatory bowel disease (IBD; Crohn disease [CD] and ulcerative colitis [UC]). Killer cell immunoglobulin‐like receptors (KIRs) are also genetically variable proteins involved in immune function. They are expressed by NK cells and certain T lymphocytes, regulate specificity and function by interaction with HLA Class I molecules, may be either inhibitory or activating and are polymorphic both in terms of alleles and haplotype gene content. Genetic associations between activating KIRs and certain autoimmune and inflammatory diseases have been reported; however, a possible association between KIR and IBD remains unclear. The aim of this study was to determine the relationship between KIR repertoire and IBD pathologies in a Spanish cohort. KIR variability was analyzed using PCR–sequence specific oligonucleotide probes (SSOP). Inhibitory KIR2DL5 was found more frequently in UC and IBD patient groups than in healthy controls (P = 0.028 and P = 0.01, respectively), as was activating KIR2DS1 (P = 0.02, Pc > 0.05, UC vs. Controls; P = 0.001, Pc = 0.01, IBD vs Controls; P = 0.01, Pc > 0.05, Controls vs CR), KIR2DS5 (P = 0.0028, Pc = 0.04, Controls vs UC; P = 0.0001, Pc = 0.0017, Controls vs IBD; P = 0.01, Pc > 0.05, Controls vs CD) and KIR3DS1 (P = 0.012, Pc > 0.05, Controls vs IBD). Our data suggest that imbalance between activating and inhibitory KIR may partially explain the different pathogeneses of these IBDs and that there is a hypothetical role for the telomeric B region (which contains both KIR2DS5 and KIR2DS1) in these diseases. 相似文献
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204.
E L Travis H D Thames T L Watkins I Kiss 《International journal of radiation biology and related studies in physics, chemistry, and medicine》1987,52(6):903-919
The kinetics of repair of sublethal damage in mouse lung was studied after fractionated doses of 137Cs gamma-rays. A wide range of doses per fraction (1.7-12 Gy) was given with interfraction intervals ranging from 0.5 to 24 h. The data were analysed by a direct method of analysis using the incomplete repair model. The half-time of repair (T1/2) was 0.76 h for the pneumonitis phase of damage (up to 8 months) and 0.65 h for the later phase of damage up to 12 months. The rate of repair was dependent on fraction size for both phases of lung damage and was faster after large dose fractions than after small fractions. The T1/2 was 0.6 h (95 per cent c.1. 0.53, 0.69) for doses per fraction greater than 5 Gy and 0.83 h (95 per cent c.1 0.76, 0.92) for doses per fraction of 2 Gy. Repair was nearly complete by 6 h, at least for the pneumonitis phase of damage. To the extent that extrapolation of these data to humans may be valid, these results imply that treatments with multiple fractions per day that involve the lung will not be limited by the necessity for interfraction intervals much longer than 6 h. 相似文献
205.
High copy number of highly similar mariner-like transposons in planarian (Platyhelminthe): evidence for a trans-phyla horizontal transfer 总被引:8,自引:2,他引:6
Garcia-Fernandez J; Bayascas-Ramirez JR; Marfany G; Munoz-Marmol AM; Casali A; Baguna J; Salo E 《Molecular biology and evolution》1995,12(3):421-431
Several DNA sequences similar to the mariner element were isolated and
characterized in the platyhelminthe Dugesia (Girardia) tigrina. They were
1,288 bp long, flanked by two 32 bp-inverted repeats, and contained a
single 339 amino acid open-reading frame (ORF) encoding the transposase.
The number of copies of this element is approximately 8,000 per haploid
genome, constituting a member of the middle- repetitive DNA of Dugesia
tigrina. Sequence analysis of several elements showed a high percentage of
conservation between the different copies. Most of them presented an intact
ORF and the standard signals of actively expressed genes, which suggests
that some of them are or have recently been functional transposons. The
high degree of similarity shared with other mariner elements from some
arthropods, together with the fact that this element is undetectable in
other planarian species, strongly suggests a case of horizontal transfer
between these two distant phyla.
相似文献
206.
207.
Kinetoplastida are protozoan organisms that probably diverged early in evolution from other eukaryotes. They are characterized
by a number of unique features with respect to their energy and carbohydrate metabolism. These organisms possess peculiar
peroxisomes, called glycosomes, which play a central role in this metabolism; the organelles harbour enzymes of several catabolic
and anabolic routes, including major parts of the glycolytic and pentosephosphate pathways. The kinetoplastid mitochondrion
is also unusual with regard to both its structural and functional properties. 相似文献
208.
209.
210.
Cannibals and their victims often share common resources and thus potentially compete. Smaller individuals are often competitively superior to larger ones because of size-dependent scaling of foraging and metabolic rates, while larger ones may use cannibalism to counter this competition. We study the interplay between cannibalism and competition using a size-structured population model in which all individuals consume a shared resource but in which larger ones may cannibalize smaller conspecifics. In this model, intercohort competition causes single-cohort cycles when cannibalism is absent. Moderate levels of cannibalism reduce intercohort competition, enabling coexistence of many cohorts. More voracious cannibalism, in combination with competition, produces large-amplitude cycles and a bimodal population size distribution with many small and few giant individuals. These coexisting "dwarfs" and "giants" have very different life histories, resulting from a reversal in importance of cannibalism and competition. The population structure at time of birth determines whether individuals suffer severe cannibalism, with the few survivors reaching giant sizes, or whether they suffer intense intracohort competition, with all individuals remaining small. These model results agree remarkably well with empirical data on perch population dynamics. We argue that the induction of cannibalistic giants in piscivorous fish is a population-dynamic emergent phenomenon that requires a combination of size-dependent cannibalism and competition. 相似文献