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排序方式: 共有120条查询结果,搜索用时 15 毫秒
111.
Safronova V Chizhevskaya E Bullitta S Andronov E Belimov A Charles TC Lindström K 《FEMS microbiology letters》2007,269(2):207-212
Seven slow-growing bacterial strains isolated from root nodules of yellow serradella (Ornithopus compressus) that originated from Asinara Island on North Western Sardinia in Italy were characterized by partial 16S rRNA gene and intergenic spacer (ITS) sequencing as well as amplified fragment length polymorphism (AFLP) genomic fingerprinting. The results indicated that the O. compressus isolates belong to the Bradyrhizobium canariense species. The analysis of ITS sequences divided the branch of B. canariense strains into two statistically separated groups (ITS clusters I and II). All the strains in ITS cluster I showed the presence of unique oligonucleotide insert TTAGAGACTTAGGTTTCTK. This insert was neither found in other described species of the family Rhizobiaceae nor in any other bacterial families and can be used as a natural and high selective genetic marker for ITS cluster I of B. canariense strains. ITS grouping of O. compressus isolates was supported by the unweighted pair group method with arithmetic averages cluster analysis of their AFLP patterns, suggesting that the strains of ITS cluster II were genetically closer to each other than to isolates from the ITS cluster I. A taxonomic importance is supposed of the revealed 19 bp ITS insert for an intraspecific division within high heterogeneous B. canariense species. 相似文献
112.
RD Calixto R Verlengia AH Crisp TB Carvalho MD Crepaldi AA Pereira AK Yamada GR da Mota CR Lopes 《Biology of sport / Institute of Sport》2014,31(4):289-294
This study aimed to compare the effects of different velocities of eccentric muscle actions on acute blood lactate and serum growth hormone (GH) concentrations following free weight bench press exercises performed by resistance-trained men. Sixteen healthy men were divided into two groups: slow eccentric velocity (SEV; n = 8) and fast eccentric velocity (FEV; n = 8). Both groups performed four sets of eight eccentric repetitions at an intensity of 70% of their one repetition maximum eccentric (1RMecc) test, with 2-minute rest intervals between sets. The eccentric velocity was controlled to 3 seconds per range of motion for SEV and 0.5 seconds for the FEV group. There was a significant difference (P < 0.001) in the kinetics of blood lactate removal (at 3, 6, 9, 15, and 20 min) and higher mean values for peak blood lactate (P = 0.001) for the SEV group (9.1 ± 0.5 mM) compared to the FEV group (6.1 ± 0.4 mM). Additionally, serum GH concentrations were significantly higher (P < 0.001) at 15 minutes after bench press exercise in the SEV group (1.7 ± 0.6 ng · mL−1) relative to the FEV group (0.1 ± 0.0 ng · mL−1). In conclusion, the velocity of eccentric muscle action influences acute responses following bench press exercises performed by resistance-trained men using a slow velocity resulting in a greater metabolic stress and hormone response. 相似文献
113.
Andre M Siqueira Janieldo A Cavalcante Shelia Vítor-Silva Roberto C Reyes-Lecca Aline C Alencar Wuelton M Monteiro Márcia AA Alexandre Mour?o Maria Paula G Caterina Guinovart Quique Bassat Maria das Gra?as C Alecrim Marcus VG Lacerda 《Memórias do Instituto Oswaldo Cruz》2014,109(5):569-576
Anaemia is amongst the major complications of malaria, a major public health problem
in the Amazon Region in Latin America. We examined the haemoglobin (Hb)
concentrations of malaria-infected patients and compared it to that of
malaria-negative febrile patients and afebrile controls. The haematological
parameters of febrile patients who had a thick-blood-smear performed at an infectious
diseases reference centre of the Brazilian Amazon between December 2009-January 2012
were retrieved together with clinical data. An afebrile community control group was
composed from a survey performed in a malaria-endemic area. Hb concentrations and
anaemia prevalence were analysed according to clinical-epidemiological status and
demographic characteristics. In total, 7,831 observations were included. Patients
with Plasmodium falciparum infection had lower mean Hb
concentrations (10.5 g/dL) followed by P. vivax-infected individuals
(12.4 g/dL), community controls (12.8 g/dL) and malaria-negative febrile patients
(13.1 g/dL) (p < 0.001). Age, gender and clinical-epidemiological status were
strong independent predictors for both outcomes. Amongst malaria-infected
individuals, women in the reproductive age had considerably lower Hb concentrations.
In this moderate transmission intensity setting, both vivax and falciparum malaria
are associated with reduced Hb concentrations and risk of anaemia throughout a wide
age range. 相似文献
114.
Sajin Bae Cornelia M Ulrich Lynn B Bailey Olga Malysheva Elissa C Brown David R Maneval Marian L Neuhouser Ting-Yuan David Cheng Joshua W Miller Yingye Zheng Liren Xiao Lifang Hou Xiaoling Song Katharina Buck Shirley AA Beresford Marie A Caudill 《Epigenetics》2014,9(3):396-403
DNA methylation is an epigenetic mechanism that regulates gene expression and can be modified by one-carbon nutrients. The objective of this study was to investigate the impact of folic acid (FA) fortification of the US food supply on leukocyte global DNA methylation and the relationship between DNA methylation, red blood cell (RBC) folate, and other one-carbon biomarkers among postmenopausal women enrolled in the Women's Health Initiative Observational Study. We selected 408 women from the highest and lowest tertiles of RBC folate distribution matching on age and timing of the baseline blood draw, which spanned the pre- (1994–1995), peri- (1996–1997), or post-fortification (1998) periods. Global DNA methylation was assessed by liquid chromatography-tandem mass spectrometry and expressed as a percentage of total cytosine. We observed an interaction (P = 0.02) between fortification period and RBC folate in relation to DNA methylation. Women with higher (vs. lower) RBC folate had higher mean DNA methylation (5.12 vs. 4.99%; P = 0.05) in the pre-fortification period, but lower (4.95 vs. 5.16%; P = 0.03) DNA methylation in the post-fortification period. We also observed significant correlations between one-carbon biomarkers and DNA methylation in the pre-fortification period, but not in the peri- or post-fortification period. The correlation between plasma homocysteine and DNA methylation was reversed from an inverse relationship during the pre-fortification period to a positive relationship during the post-fortification period. Our data suggest that (1) during FA fortification, higher RBC folate status is associated with a reduction in leukocyte global DNA methylation among postmenopausal women and; (2) the relationship between one-carbon biomarkers and global DNA methylation is dependent on folate availability. 相似文献
115.
Sarfraz A Tunio Neil J Oldfield Dlawer AA Ala'Aldeen Karl G Wooldridge David PJ Turner 《BMC microbiology》2010,10(1):280
Background
Glyceraldehyde 3-phosphate dehydrogenases (GAPDHs) are cytoplasmic glycolytic enzymes, which although lacking identifiable secretion signals, have also been found localized to the surface of several bacteria (and some eukaryotic organisms); where in some cases they have been shown to contribute to the colonization and invasion of host tissues. Neisseria meningitidis is an obligate human nasopharyngeal commensal which can cause life-threatening infections including septicaemia and meningitis. N. meningitidis has two genes, gapA-1 and gapA-2, encoding GAPDH enzymes. GapA-1 has previously been shown to be up-regulated on bacterial contact with host epithelial cells and is accessible to antibodies on the surface of capsule-permeabilized meningococcal cells. The aims of this study were: 1) to determine whether GapA-1 was expressed across different strains of N. meningitidis; 2) to determine whether GapA-1 surface accessibility to antibodies was dependant on the presence of capsule; 3) to determine whether GapA-1 can influence the interaction of meningococci and host cells, particularly in the key stages of adhesion and invasion. 相似文献116.
Albert Eduardo Silva Martins Norma Lucena-Silva Renan Gomes Garcia Stefan Welkovic Aureliana Barboza Maria Luiza Bezerra Menezes Magda Maruza Terezinha Tenório Ricardo AA Ximenes 《Memórias do Instituto Oswaldo Cruz》2014,109(6):738-747
Human immunodeficiency virus (HIV)-positive patients have a greater prevalence of
coinfection with human papillomavirus (HPV) is of high oncogenic risk. Indeed, the
presence of the virus favours intraepithelial squamous cell lesion progression and
may induce cancer. The aim of this study was to evaluate the prevalence of HPV
infection, distribution of HPV types and risk factors among HIV-positive patients.
Cervical samples from 450 HIV-positive patients were analysed with regard to oncotic
cytology, colposcopy and HPV presence and type by means of polymerase chain reaction
and sequencing. The results were analysed by comparing demographic data and data
relating to HPV and HIV infection. The prevalence of HPV was 47.5%. Among the
HPV-positive samples, 59% included viral types of high oncogenic risk. Multivariate
analysis showed an association between HPV infection and the presence of cytological
alterations (p = 0.003), age greater than or equal to 35 years (p = 0.002), number of
partners greater than three (p = 0.002), CD4+ lymphocyte count <
200/mm3 (p = 0.041) and alcohol abuse (p = 0.004). Although high-risk
HPV was present in the majority of the lesions studied, the low frequency of HPV 16
(3.3%), low occurrence of cervical lesions and preserved immunological state in most
of the HIV-positive patients were factors that may explain the low occurrence of
precancerous cervical lesions in this population. 相似文献
117.
Zverev A. O. Pershina E. V. Shapkin V. M. Kichko A. K. Mitrofanova O. P. Kobylyanskii V. D. Yuzikhin O. S. Belimov A. A. Andronov E. E. 《Microbiology》2020,89(2):231-241
Microbiology - The composition of rhizosphere microbial communities was studied for different species and varieties of agricultural gramineous plants (rye and wheat) grown in the soils contrasting... 相似文献
118.
Archives of Microbiology - 相似文献
119.
120.