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291.
Bont WS 《Molecular biology reports》2009,36(5):959-964
In order to explain the experimentally obtained results with biomembranes it has been assumed, that the diameter of all vesicles,
defined by a lipid bilayer, form a perfect crystal. Later on it appeared that biomembranes are liquid crystals. Nevertheless
already with biomembranes as crystals it was possible to calculate the diameters of all existing vesicles. As shown in the
present paper, the results with liquid crystals were identical to those with a perfect crystal-model. Here I demonstrate that
the geometric progression of the diameters of vesicles of biomembranes is based on the entropy of the lipids and it is shown
that the diameters of biomembranes fit four geometric series. The surface areas of these series of biomembranes can be approximated
by the two geometric series published previously.
The experiments and the theoretical studies on which this work is based have been carried out at the Netherlands Cancer Institute,
Amsterdam, The Netherlands. 相似文献
292.
A Neuro-Comparative Study between Single/Successive Thorium Dose Intoxication and Alginate Treatment
Mohamed M. Rezk 《Biological trace element research》2018,185(2):414-423
The adult male albino rats were grouped into five groups (control group and four variably treated groups with thorium (Th) in single or successive with or without alginate treatment). The IP administration of thorium nitrate (13.6 mg/kg b.wt.) induced a regional distribution and accumulation ordered as cerebellum > cerebral cortex > brain stem > hippocampus > hypothalamus > striatum. Also, it induces a significant increase in Na+, Ca2+, and Fe3+ ion content and malondialdehyde (MDA) level while K+ ions and glutathione (GSH) level were significantly decreased. On the other hand, the daily oral administration of 5% alginate showed a significant decreasing in the accumulation of thorium in the different brain areas and mitigated its hazardous effects. By the alginate treatment, Na+, Ca2+, Fe3+, and level of MDA were declined while K+ ions and GSH level showed a significant increase. The improvement of the investigated parameters was attributed to the specific chelating, regeneration, and antioxidant properties of the alginate. So, alginate administration could ameliorate the hazardous effects of thorium nitrate. 相似文献
293.
Nine white-rot fungal strains were screened for biodecolourization of brilliant green, cresol red, crystal violet, congo red
and orange II. Dichomitus squalens, Phlebia fascicularia and P. floridensis decolourized all of the dyes on solid agar medium and possessed better decolourization ability than Phanerochaete chrysosporium when tested in nitrogen-limited broth medium. Journal of Industrial Microbiology & Biotechnology (2002) 28, 201–203 DOI: 10.1038/sj/jim/7000222
Received 12 July 2001/ Accepted in revised form 22 October 2001 相似文献
294.
Lakhdar Ghazouani Nesrine Abboud Sonia Ben Hadj Khalifa Claire Perret Viviane Nicaud Wassim Youssef Almawi François Cambien Touhami Mahjoub 《Molecular biology reports》2011,38(1):495-501
P-selectin (SELP) and its counter-receptor, P-selectin glycoprotein ligand-1 (PSGL-1), play key role in the transient attachment
of leukocytes to endothelial cells predisposing to coronary heart disease (CHD). In the current report, 293 angiographically
proven CHD patients and 327 age, gender, and race-matched controls were included. Our aim was to evaluate the contribution
to CHD of the following SNPs: C-2123G, G-1969A and T715P in SELP, Met62Ile and the VNTR variants in PSGL-1 gene in a North African population from Tunisia. While there were no significant differences in the distribution of SELP
or PSGL-1 alleles or genotypes between patients and controls, a trend for a significant association of the C-2123G genotypes
distribution with incident CHD was observed (P = 0.06). Assuming an additive model of transmission, the risk was 74% higher among subjects carrying the GG genotypes in
comparison to those carrying the CC genotype (OR = 1.74 [1.01–2.98], P = 0.04) and 80% higher in the recessive model (OR = 1.80 [1.08–3.01], P = 0.02). Haplotype analysis did not identify any specific SELP or PSGL-1 haplotypes to be associated with CHD. The present
study demonstrated no evidence of association between individual SELP or PSGL-1 SNPs or haplotypes with incident CHD. However,
this study replicates absence of association of the mostly studied SNP, T715P, previously reported in individuals with African
origin. 相似文献
295.
296.
In many species, including wheat, crossing over is distal, and the proximal regions of chromosome arms contribute little to
genetic maps. This was thought to be a consequence of terminal initiation of synapsis favoring distal crossing over. However,
in an inverted rye chromosome arm, the pattern of metaphase I chiasmata was also inverted, suggesting that crossover frequencies
were specific to chromosome segments. Here, wheat chromosome arms 2BS and 4AL, with essentially entire arms inverted in reverse
tandem duplications (rtd), were studied in the MI of meiosis. Inversion–duplication placed the recombining segments in the
middle of the arms. While the overall pairing frequencies of the inverted–duplicated arms were considerably reduced relative
to normal arms, chiasmata, if present, were always located in the same regions as in structurally normal arms, and relative
chiasma frequencies remained the same. The frequencies of fragment or fragment + bridge configurations in AI and AII indicated
that of the two tandemly arranged copies of segments in rtds, the more distal inverted segments were more likely to cross
over than the segments in their original orientations. These observations show that also in wheat, relative crossover frequencies
along chromosome arms are predetermined and independent of the segment location. The segments normally not licensed to cross
over do not do so even when placed in seemingly most favorable positions for it. 相似文献
297.
Yasuro Fuse Takahiro Okamoto Kazuhide Hayakawa Hajime Karatani Etsu Yamada 《Limnology》2016,17(3):207-221
Humic substances extracted and purified from bottom sediments of northern Lake Biwa, Japan, in November 2012 and 2013 were characterized using elemental analysis, Fourier-transform infrared spectroscopy, hydrogen-1 nuclear magnetic resonance (1H NMR) analysis, and pyrolysis gas chromatography/mass spectrometry (Py-GC/MS). The infrared (IR) bands in the spectra of humic acids showed the presence of amide linkages and polysaccharides. Results of 1H NMR analysis showed that the humic acids contained approximately twice the number of aliphatic protons as those in the Japanese soil standards used for comparison. Results of the Py-GC/MS analysis, which evaluates pyrolysis temperature dependency of the amount of pyrolysis products, showed that the generation of pyrolysis products in humic acids also differed from that in Japanese soil standards but was similar to that of phytoplankton in Lake Biwa. This analysis method is the first to provide extensive information about the chemical structure of humic substances; conventional Py-GC/MS provides limited information for a single temperature. Data suggest that humic acids in lake sediments are related to chemical characteristics of phytoplankton. Results shed new light on the origins of humic substances in deep-water-lake sediments and provide insights into material recycling in such sediments. 相似文献
298.
299.
Erwinia amylovora causes fire blight of apple, pear, and other members of the Rosaceae family. The enzyme LuxS catalyzes the last step in the
production of autoinducer-2 (AI-2), a molecule implicated with quorum sensing in many bacterial species. It is now well recognized
that LuxS also plays a central role in sulfur metabolism and in the activated methyl cycle, which is responsible for the generation
of S-adenosyl-l-methionine. A research paper has reported that luxS is not involved with quorum sensing in Er. amylovora, but in our study, Er. amylovora strain NCPPB1665 (Ea1665) produced luxS-dependent extracellular AI-2 activity. Additionally, the maximal AI-2 activity occurred during late-exponential and early-stationary
growth phases and diminished during the stationary phase. The luxS mutant of Ea1665 was constructed, and the phenotypes of a defined luxS mutant have been characterized. Inactivation of luxS in Ea1665 impaired motility, extracellular polysaccharide (EPS) production, and tolerance for hydrogen peroxide, and reduced virulence
on pear leaves.
Yan Gao and Junxian Song contributed equally to this research. 相似文献
300.
Eric Letouzé Yves Allory Marc A Bollet François Radvanyi Frédéric Guyon 《Genome biology》2010,11(7):R76
We present a computational method, TuMult, for reconstructing the sequence of copy number changes driving carcinogenesis,
based on the analysis of several tumor samples from the same patient. We demonstrate the reliability of the method with simulated
data, and describe applications to three different cancers, showing that TuMult is a valuable tool for the establishment of
clonal relationships between tumor samples and the identification of chromosome aberrations occurring at crucial steps in
cancer progression. 相似文献