排序方式: 共有92条查询结果,搜索用时 281 毫秒
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Lamia Lahouar Fatma Ghrairi Mouldi El Felah Hichem Ben Salem Abdel Hedi Miled Mohamed Hammami Lotfi Achour 《Journal of physiology and biochemistry》2011,67(1):27-34
The aim of the present study is to evaluate the effects of diet enriched with dietary fiber of barley variety “Rihane” and
azoxymethane on serum and liver lipid variables in male rats. Forty male rats were divided into four groups and fed on control
diet or experimental diet that contained control enriched with dietary fiber of barley variety “Rihane”. Animals were injected
with saline (controls) or azoxymethane (20 mg/kg body weight s.c.) at 7 and 8 weeks of age. The experimental diet significantly
decreased cholesterol level compared with the control diet. Rats fed with BR diet significantly increased the serum high-density
lipoprotein (HDL) cholesterol and significantly decreased low-density lipoprotein (LDL) cholesterol concentrations. The experimental
diet decreased the atherogenic index (p < 0.05) compared with the control diet. Whereas the azoxymethane induced a significant increase of liver lipid, serum LDL
and triglyceride concentrations, but it caused a significant reduction of HDL. Consequently, the ratio of HDL/TC decreased
significantly compared with the control (p < 0.05). Accordingly, these results indicated that the diet enriched with dietary fiber of barley variety “Rihane” could
be effective in decreasing the atherogenic risk factors in rats whereas the use of the azoxymethane as colon-specific carcinogen
substance altered the lipid metabolism. 相似文献
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Jean-Yves Winum Alessandro Cecchi Achour Seridi Andrea Scozzafava Jean-Louis Montero Claudiu T. Supuran 《Journal of enzyme inhibition and medicinal chemistry》2013,28(4):477-481
A series of N-cyanomethyl aromatic sulfonamides and bis-sulfonamides was prepared by reaction of arylsulfonyl halides with aminoacetonitrile. The obtained derivatives incorporated various aryl moieties, such as 4-halogeno/alkyl/aryl/nitro-substituted-phenyl, pentafluorophenyl or 2-naphthyl. Moderate inhibitory activity was detected for some compounds against the cytosolic human isoform II of the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1), hCA II, with inhibition constants of 90, 180 and 560 nM for the 4-nitrophenyl-, 4-iodophenyl- and pentafluorophenyl-N-cyanomethylsulfonamides, respectively. Other derivatives acted as weak inhibitors of isoforms hCA I (KIs of 720 nM–45 μM), hCA II (KIs of 1000–9800 nM) and hCA IX (KIs of 900–10200 nM). Thus, the N-cyanomethylsulfonamide zinc binding group is less effective than the sulfonamide, sulfamate or sulfamide ones for the design of effective CA inhibitors. 相似文献
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Arij Mechergui Wafa Achour Assia Ben Hassen 《World journal of microbiology & biotechnology》2014,30(8):2181-2188
We aimed to compare accuracy of genus and species level identification of Neisseria spp. using biochemical testing and 16S rRNA sequence analysis. These methods were evaluated using 85 Neisseria spp. clinical isolates initially identified to the genus level by conventional biochemical tests and API NH system (Bio-Mérieux®). In 34 % (29/85), more than one possibility was given by 16S rRNA sequence analysis. In 6 % (5/85), one of the possibilities offered by 16S rRNA gene sequencing, agreed with the result given by biochemical testing. In 4 % (3/85), the same species was given by both methods. 16S rRNA gene sequencing results did not correlate well with biochemical tests. 相似文献
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Velloso LM Michaëlsson J Ljunggren HG Schneider G Achour A 《Journal of immunology (Baltimore, Md. : 1950)》2004,172(9):5504-5511
Lymphocytic choriomeningitis virus infection of H-2(b) mice generates a strong CD8(+) CTL response mainly directed toward three immunodominant epitopes, one of which, gp33, is presented by both H-2D(b) and H-2K(b) MHC class I molecules. This CTL response acts as a selective agent for the emergence of viral escape variants. These variants generate altered peptide ligands (APLs) that, when presented by class I MHC molecules, antagonize CTL recognition and ultimately allow the virus to evade the cellular immune response. The emergence of APLs of the gp33 epitope is particularly advantageous for LCMV, as it allows viral escape in the context of both H-2D(b) and H-2K(b) MHC class I molecules. We have determined crystal structures of three different APLs of gp33 in complex with both H-2D(b) and H-2K(b). Comparison between these APL/MHC structures and those of the index gp33 peptide/MHC reveals the structural basis for three different strategies used by LCMV viral escape mutations: 1) conformational changes in peptide and MHC residues that are potential TCR contacts, 2) impairment of APL binding to the MHC peptide binding cleft, and 3) introduction of subtle changes at the TCR/pMHC interface, such as the removal of a single hydroxyl group. 相似文献
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Summary Following the demise of the stromatoporoid-coral reef community in Late Frasnian time, Lower Carboniferous carbonate shelf
profiles possessed a ramp geometry, with major organic buildups represented by mud-rich mounds. Microfacies petrography of
the exceptionally well-preserved Upper Viséan (Lower Carboniferous) carbonate ramp of the Béchar Basin, Algerian Sahara, may
well contribute significantly to our understanding of the paleoecological zonation of Carboniferous non-rimmed platforms,
and of the still enigmatic mounds commonly referred to as Waulsortian banks or mounds.
Facies are grouped into two broad groups: (a) a mound facies group which comprises sponge wackestone-bafflestone, sponge-fenestellid
bafflestone-wackestone, crinoid wackestone-packstone, and bedded flanks of intraclastic wackestone-packstone, all four facies
composing the actual mud-rich mounds, and (b) a supramound facies group composed of coral-microbial framestone, crinoid packstone-grainstone,
algal-foraminiferal grainstone and oolite grainstone.
Calcareous algae are important bathymetric indicators and are used to delineate three bathymetric zones based on light penetration:
the aphotic zone, which contains no calcareous algae; the dysphotic zone, where there is little ambient light, and which is
characterized by the presence of red algae (Fasciella, Ungdarella, Stacheia, Epistacheoides) and absence of green algae; and the euphotic zone, which receives the full spectrum of sunlight, and is characterized by
the occurrence of both green algae (Koninckopora, Kamaenella, Kamaena, Palaeoberesella, Calcisphaera, Anthracoporellopsis, Issinella, Exvotarisella) and red algae.
Integration of algal zonation, distribution of the other biota, and recurrence of distinct assemblages, enable recognition
of seven depth-related benthic assemblages. Together with the physical properties of the facies, the benthic assemblages were
used to define seven bathymetric zones, from upper to lower ramp: (1) algal assemblage (upper ramp); (2) crinoid-ramose bryozoan
assemblage (mid-ramp); and (3) productid brachiopod assemblage, (4) colonial rugose coral-microbial encruster assemblage,
(5) crinoid-fenestellid assemblage, (6) sponge-fenestellid, and (7) sponge assemblage (lower ramp).
The vertical zonation of the mud-rich mounds and associated facies differ from that reported from the classical Upper Tournaisian-Lower
Viséan Waulsortian mound-bearing successions. 相似文献
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Induction of anti-gp160 cytotoxic T cells cross-reacting with various V3 loop P18 peptides in human immunodeficiency virus type 1 envelope-immunized individuals. 下载免费PDF全文
Cytotoxic T lymphocytes (CTL) may be important to prevent cell-to-cell transmission of human immunodeficiency virus type 1 (HIV-1), the agent responsible for AIDS. In this study, we investigated the epitope specificity of CTLs induced in individuals immunized against the virus envelope glycoprotein gp160. The determinant of HIV-1 gp160 for the stimulation of CTL is located in a region of high sequence variability among HIV-1 isolates, the so-called V3 loop P18. Using a panel of P18 peptides, we compared the CTL specificities of cells from two individuals immunized with vaccinia virus recombinants expressing the envelope glycoproteins from two different strains of HIV-1, IIIB and SIMI. For this purpose, CTLs specific for the IIIB P18 peptide (RIQRGPGRAFVTIGK) were compared with CTLs for the site from the SIMI isolate (TLHMGPKRAFYATGD). The results indicate that in contrast to CD8+ CTLs induced by the glycoprotein from strain IIIB, CD8+ CTLs induced by strain SIMI strongly cross-reacted with targets presenting P18 peptides as well as envelope proteins from the divergent MN and RF isolates but failed to cross-react with targets that presented the IIIB peptide. These data have implications for the design of an HIV vaccine. 相似文献
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