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11.
Background
The human menstrual cycle is known to exhibit a significant amount of unexplained variability. This variation is typically dismissed as random fluctuations in an otherwise periodic and predictable system. Given the many delayed nonlinear feedbacks in the multiple levels of the reproductive endocrine system, however, the menstrual cycle can properly be construed as the output of a nonlinear dynamical system, and such a system has the possibility of being in a chaotic trajectory. We hypothesize that this is in fact the case and that it accounts for the observed variability. 相似文献12.
Sequence analysis of the ribosomal DNA internal transcribed spacer 2 from populations of Anopheles nuneztovari (Diptera: Culicidae) 总被引:3,自引:0,他引:3
Sequence variation of the ribosomal DNA internal transcribed spacer 2
(ITS2) was examined for populations of the malaria vector Anopheles
nuneztovari collected in Colombia, Venezuela, Bolivia, Suriname, and
Brazil. Mosquitoes from Colombia and Venezuela had identical ITS2 sequences
and were distinguished from sequences in other populations by three
insertion/deletion events (indels) and by one transversion. The length of
the ITS2 was 363-369 bp, and it had a G+C content of 55.3%- 55.7%.
Variation in the length of the ITS2 between and within populations was due
to indels in simple repeats. ITS2 consensus sequences were similar or
identical for samples from the following three groups: (1) Colombia,
Bolivia, and Venezuela; (2) Suriname and northern Brazil; and (3) eastern
and central Brazil. The presence of two different consensus sequences from
a single location near Manaus, Brazil, suggests that populations from
eastern Brazil and those from Suriname converge in this region of the
Amazon Basin. These data show that putative cryptic species of An.
nuneztovari are distinguished by very minor differences in DNA sequence of
the ITS2 region.
相似文献
13.
JU Nnadi IN Dimelu SI Nwani JC Madu CI Atama GN Attamah 《African Journal of Aquatic Science》2018,43(1):27-34
The current study investigated the effects of termite insecticide, Termex® (imidacloprid 35.50% SC), on biometric variations and oxidative stress biomarkers in Clarias gariepinus. Fish were exposed to 4.00 and 6.00 µg l–1 sublethal Termex® concentrations in 2017. The gill and liver tissues were sampled on days 7, 14, 21 and 28 and the results indicated that hepatosomatic index (HSI) decreased significantly when compared with the control on days 14, 21 and 28. The condition factor (CF) and viscera-somatic index (VSI) also decreased during the study period. The decrease was greater at 6.00 µg l–1 Termex® concentration on days 21 and 28 for CF and days 14 to 28 for VSI, respectively. The lipid peroxidation (LPO) in both tissues was highest in the 6.00 µg l?1 Termex® and increased with the duration. There was significant decrease (p < 0.05) in superoxide dismutase and glutathione peroxidase values, but significant increase in catalase activity in both tissues. The values of glutathione reductase in both tissues were comparable to the control, except on days 21 and 28 in the liver. There was negative correlation between the LPO in tissues and the HSI, CF and VSI values. The use of Termex® in the environment should be monitored to safeguard the health of aquatic organisms. 相似文献
14.
Alzheimer''s disease (AD) is the most common form of dementia. It is the sixth leading cause of death in old age people. Despite
recent advances in the field of drug design, the medical treatment for the disease is purely symptomatic and hardly effective. Thus
there is a need to understand the molecular mechanism behind the disease in order to improve the drug aspects of the disease. We
provided two contributions in the field of proteomics in drug design. First, we have constructed a protein-protein interaction
network for Alzheimer''s disease reviewed proteins with 1412 interactions predicted among 969 proteins. Second, the disease
proteins were given confidence scores to prioritize and then analyzed for their homology nature with respect to paralogs and
homologs. The homology persisted with the mouse giving a basis for drug design phase. The method will create a new drug design
technique in the field of bioinformatics by linking drug design process with protein-protein interactions via signal pathways. This
method can be improvised for other diseases in future. 相似文献
15.
16.
Bas E Dutilh Cristiane C Thompson Ana CP Vicente Michel A Marin Clarence Lee Genivaldo GZ Silva Robert Schmieder Bruno GN Andrade Luciane Chimetto Daniel Cuevas Daniel R Garza Iruka N Okeke Aaron Oladipo Aboderin Jessica Spangler Tristen Ross Elizabeth A Dinsdale Fabiano L Thompson Timothy T Harkins Robert A Edwards 《BMC genomics》2014,15(1)
Background
Vibrio cholerae is a globally dispersed pathogen that has evolved with humans for centuries, but also includes non-pathogenic environmental strains. Here, we identify the genomic variability underlying this remarkable persistence across the three major niche dimensions space, time, and habitat.Results
Taking an innovative approach of genome-wide association applicable to microbial genomes (GWAS-M), we classify 274 complete V. cholerae genomes by niche, including 39 newly sequenced for this study with the Ion Torrent DNA-sequencing platform. Niche metadata were collected for each strain and analyzed together with comprehensive annotations of genetic and genomic attributes, including point mutations (single-nucleotide polymorphisms, SNPs), protein families, functions and prophages.Conclusions
Our analysis revealed that genomic variations, in particular mobile functions including phages, prophages, transposable elements, and plasmids underlie the metadata structuring in each of the three niche dimensions. This underscores the role of phages and mobile elements as the most rapidly evolving elements in bacterial genomes, creating local endemicity (space), leading to temporal divergence (time), and allowing the invasion of new habitats. Together, we take a data-driven approach for comparative functional genomics that exploits high-volume genome sequencing and annotation, in conjunction with novel statistical and machine learning analyses to identify connections between genotype and phenotype on a genome-wide scale.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-654) contains supplementary material, which is available to authorized users. 相似文献17.