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1.
Background
Chow and Liu showed that the maximum likelihood tree for multivariate discrete distributions may be found using a maximum weight spanning tree algorithm, for example Kruskal's algorithm. The efficiency of the algorithm makes it tractable for high-dimensional problems. 相似文献2.
Heterogeneity of human C4 gene size 总被引:7,自引:0,他引:7
In this article we present a study showing that the human C4 genes differ in length because of the presence or absence of a 6.5 kb intron near the 5 end of the gene. DNA from individuals of known HLA, factor B, and C4 haplotypes was analyzed for restriction fragment length polymorphism (RFLP) by Southern blot analysis with C4-specific cDNA probes. The RFLP patterns obtained showed that the C4 genes are either 22.5 kb or 16 kb in length. They are referred to as long and short C4 genes, respectively. A population study was carried out to examine the distribution of the gene size according to C4 allotypes and haplotypes. Long C4 genes included all C4A genes studied and also some C4B allotypes, e. g., B1 on most C4 A3B1 haplotypes. Similarly, C4B null genes were found to be of the long form. Other C4B allotypes tested were found to be coded for by short C4 genes, including B2, B1 in C4 A6B1 and C4 AQOB1 (with a single C4B gene haplotype).Abbreviations used in this paper C4
fourth component of complement
- C2
second component of complement
- BF
factor B
- MHC
major histocompatibility complex
- RFLP
restriction fragment length polymorphism
- EDTA
ethylenediaminetetraacetic acid
- SDS
lauryl sulfate, sodium salt 相似文献
3.
Fushi Wen Ho Hyung Woo Elizabeth A. Pierson Toril D. Eldhuset C. G. Fossdal N. E. Nagy Martha C. Hawes 《Plant Molecular Biology Reporter》2009,27(1):58-68
Root cap development in cereals and legumes is self-regulated by a repressor that accumulates in the extracellular environment,
and immersing the root tip into water results in renewed cap development. By exploiting this phenomenon, root cap mitosis
and differentiation can be synchronously induced among populations. In Pisum sativum L., messenger RNA (mRNA) differential display revealed changes in expression of approximately 1% of the sample mRNA population
within minutes of induced cap turnover. This profile changes sequentially over a period of 30 min, then stabilizes. Microarray
analysis of Medicago truncatula root caps confirmed changes in expression of approximately 1% of the target population, within minutes. A cell specific marker
for cap turnover exhibited the same temporal and spatial expression profile in the gymnosperm species Norway spruce (Picea abies) as in pea. Induced cap development provides a means to profile cell-specific gene expression among phylogenetically diverse
species from the early moments of mitosis and cellular differentiation. 相似文献
4.
S?ren Franzenburg Sebastian Fraune Philipp M Altrock Sven Künzel John F Baines Arne Traulsen Thomas CG Bosch 《The ISME journal》2013,7(4):781-790
Animals are colonized by complex bacterial communities. The processes controlling community membership and influencing the establishment of the microbial ecosystem during development are poorly understood. Here we aimed to explore the assembly of bacterial communities in Hydra with the broader goal of elucidating the general rules that determine the temporal progression of bacterial colonization of animal epithelia. We profiled the microbial communities in polyps at various time points after hatching in four replicates. The composition and temporal patterns of the bacterial communities were strikingly similar in all replicates. Distinct features included high diversity of community profiles in the first week, a remarkable but transient adult-like profile 2 weeks after hatching, followed by progressive emergence of a stable adult-like pattern characterized by low species diversity and the preponderance of the Betaproteobacterium Curvibacter. Intriguingly, this process displayed important parallels to the assembly of human fecal communities after birth. In addition, a mathematical modeling approach was used to uncover the organizational principles of this colonization process, suggesting that both, local environmental or host-derived factor(s) modulating the colonization rate, as well as frequency-dependent interactions of individual bacterial community members are important aspects in the emergence of a stable bacterial community at the end of development. 相似文献
5.
Yakovlev Igor A. Carneros Elena Lee YeonKyeong Olsen Jorunn E. Fossdal Carl Gunnar 《Planta》2016,243(5):1237-1249
Planta - A significant number of epigenetic regulators were differentially expressed during embryogenesis at different epitype-inducing conditions. Our results support that methylation of DNA and... 相似文献
6.
PR Marcelino MS Aoki AFS Arruda CG Freitas A Mendez-Villanueva A Moreira 《Biology of sport / Institute of Sport》2016,33(1):37-42
The purpose of this study was to investigate the effect of court size on physiological responses and physical performance of young elite basketball players. Twelve male basketball players (18.6 ± 0.5 years; 88.8 ± 14.5 kg; 192.6 ± 6.5 cm) from an under-19 team performed two small-sided games (matches) with different court areas (28x15 m and 28x9 m; 28x15 and 28x9 protocols). The number of players (3x3) was kept the same in each protocol. The players performed a repeated-sprint ability (RSA) test before and after each match. Blood lactate concentration was collected before (pre) and after (post) the matches, and the session rating of perceived exertion (session-RPE) was determined 30 minutes after the match. Best and mean time in the RSA test were not different between the 28x15 and the 28x9 match protocols (p > 0.05). A significant difference was observed for lactate concentration from pre- to post-match (p < 0.05) in both protocols (28x15 and 28x9); however, there was no significant interaction between protocols. A similar session-RPE mean score (28x15: 7.2 ± 1.4 and 28x9: 6.6 ± 1.4) was detected for both protocols (p > 0.05, ES=0.41). In summary, the results of the current study suggest that the different court areas induced similar responses. Although there was no significant difference in effort perception, players tended to perceive a greater effort in the larger court size. 相似文献
7.
8.
Abstract Helicoverpa armigera oviposition preference for, and larval development on sorghum hybrids with differing resistance to sorghum midge, Stenodiplosis sorghicola , were investigated. When H. armigera larvae were fed seed of resistant and susceptible hybrids in the laboratory there were no differences in larval and pupal sizes or the rate of development. The same result was recorded when larvae fed on panicles on plants in a glasshouse. On some sampling occasions, significantly more eggs were laid on panicles of resistant hybrids in the field. This occurred when plants were in plots and also in a mixed planting. Midge-resistance status did not affect levels of egg parasitism. In a field study using recombinant inbred lines between a midge-resistant and a midge-susceptible line, no relationship was found between level of resistance and oviposition of H. armigera . We conclude that, although midge-resistant hybrids are sometimes preferred for oviposition by H. armigera, the resistance per se does not determine this preference. Egg survival, larval survival, development and resultant damage are not significantly affected by the midge-resistance status of the host. 相似文献
9.
Multiplex real-time PCR for monitoring Heterobasidion annosum colonization in Norway spruce clones that differ in disease resistance 总被引:1,自引:0,他引:1
Hietala AM Eikenes M Kvaalen H Solheim H Fossdal CG 《Applied and environmental microbiology》2003,69(8):4413-4420
A multiplex real-time PCR assay was developed to monitor the dynamics of the Picea abies-Heterobasidion annosum pathosystem. Tissue cultures and 32-year-old trees with low or high resistance to this pathogen were used as the host material. Probes and primers were based on a laccase gene for the pathogen and a polyubiquitin gene for the host. The real-time PCR procedure was compared to an ergosterol-based quantification method in a tissue culture experiment, and there was a strong correlation (product moment correlation coefficient, 0.908) between the data sets. The multiplex real-time PCR procedure had higher resolution and sensitivity during the early stages of colonization and also could be used to monitor the host. In the tissue culture experiment, host DNA was degraded more rapidly in the clone with low resistance than in the clone with high resistance. In the field experiment, the lesions elicited were not strictly proportional to the area colonized by the pathogen. Fungal colonization was more restricted and localized in the lesion in the clone with high resistance, whereas in the clone with low resistance, the fungus could be detected until the visible end of the lesion. Thus, the real-time PCR assay gives better resolution than does the traditionally used lesion length measurement when screening host clones for resistance. 相似文献
10.
D Taruscio C Morciano P Laricchiuta P Mincarone F Palazzo CG Leo S Sabina R Guarino J Auld T Sejersen D Gavhed K Ritchie M Hilton-Boon J Manson PG Kanavos D Tordrup V Tzouma Y Le Cam J Senecat G Filippini S Minozzi C Del Giovane H Schünemann JJ Meerpohl B Prediger L Schell R Stefanov G Iskrov T Miteva-Katrandzhieva P Serrano-Aguilar L Perestelo-Perez MM Trujillo-Martín J Pérez-Ramos A Rivero-Santana A Brand H van Kranen K Bushby A Atalaia J Ramet L Siderius M Posada I Abaitua-Borda V Alonso Ferreira M Hens-Pérez FJ Manzanares 《Orphanet journal of rare diseases》2014,9(Z1):O14