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91.
A number of studies have suggested that an immune response to human leukocyte antigen (HLA) alloantigens may contribute to protection against HIV infection. In the present study, we examined the effect of alloantigen-stimulated cell lines obtained from peripheral blood mononuclear cells (PBMC) of HIV-uninfected (HIV-) individuals and the soluble factors produced by these cell lines on HIV-1 replication. Multiple in vitro restimulation with irradiated allogeneic PBMC from HIV- donors resulted in the expansion of CD8(+) T-cell lines that inhibited HIV-1 replication when cocultured with either autologous or heterologous in vitro-infected phytohemagglutinin (PHA) blasts. Supernatants from the alloantigen-stimulated cell lines also inhibited HIV replication in both PHA blasts and a chronically infected cell line. The alloantigen-stimulated cell lines and the factors they produced inhibited both T-cell-tropic (T) and macrophage-tropic (M) isolates of HIV-1. Blocking experiments using anti-chemokine antibodies suggested that this inhibition of HIV replication was not due to the beta-chemokines present in cocultures of cell lines with HIV-infected blasts. These results indicate that alloantigen-stimulation of PBMC from HIV- individuals activates CD8(+) T cells that produce soluble factor(s) that inhibit HIV replication of a wide spectrum of HIV-1 isolates through a chemokine-independent mechanism. This is a US government work. There are no restrictions on its use. 相似文献
92.
E Caldiroli F Marino M Cosentino F De Ponti AM Fietta A Mazzone A Zibetti S Lecchini GM Frigo 《Canadian Metallurgical Quarterly》1998,57(4):215-221
AIM: To gain a full understanding of the concept of equity and means of promoting and monitoring a more equitable healthservice. BACKGROUND: With previous policy decisions having sidelined equity, a new government is likely to wish to reverse this trend. ORIGINS OF INFORMATION: Government and expert opinion. DATA ANALYSIS: A critical approach to previous literature. KEY ISSUES: Equity is not a unitary concept and so it is explored and dissected using the framework of: Distribution of Resources, Access and Uptake of Healthcare, Standards and Outcomes of Healthcare, Health Status. Means of improving and monitoring equity in these four areas are suggested. CONCLUSIONS: There are a number of ways of considering the concept of equity and for any fruitful discussion to occur there needs to be an agreed working definition. Specific topics are discussed where equity is lacking and a plan of action is suggested which is likely to improve equity in the areas identified. 相似文献
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95.
GM Rossolini S Schippa ML Riccio F Berlutti LE Macaskie MC Thaller 《Canadian Metallurgical Quarterly》1998,54(8):833-850
Bacterial nonspecific acid phosphohydrolases (NSAPs) are secreted enzymes, produced as soluble periplasmic proteins or as membrane-bound lipoproteins, that are usually able to dephosphorylate a broad array of structurally unrelated substrates and exhibit optimal catalytic activity at acidic to neutral pH values. Bacterial NSAPs are monomeric or oligomeric proteins containing polypeptide components with an M(r) of 25-30 kDa. On the basis of amino acid sequence relatedness, three different molecular families of NSAPs can be distinguished, indicated as molecular class A, B and C, respectively. Members of each class share some common biophysical and functional features, but may also exhibit functional differences. NSAPs have been detected in several microbial taxa, and enzymes of different classes can be produced by the same bacterial species. Structural and phyletic relationships exist among the various bacterial NSAPs and some other bacterial and eucaryotic phosphohydrolases. Current knowledge on bacterial NSAPs is reviewed, together with analytical tools that may be useful for their characterization. An overview is also presented concerning the use of bacterial NSAPs in biotechnology. 相似文献
96.
M Montagna O Serova BS Sylla MG Mattei GM Lenoir 《Canadian Metallurgical Quarterly》1996,98(6):738-740
The h-PRL-1 gene codes for a new phosphotyrosine phosphatase that may play an important role in the control of basic cellular processes such as cell growth and proliferation. Using the cDNA of the h-PRL-1 gene as a probe, we examined a somatic mouse and hamster x human hybrid panel and found that chromosomes 1, 17 and 11 harbor sequences homologous to h-PRL-1. By in situ hybridization of metaphase spreads, subchromosomal localizations were determined at bands 1p35-p34, 17q12-q21 and 11q24-q25; in addition, a faint signal was detected at 12q24. The chromosomal assignment of the genes homologous to h-PRL-1 will help the investigation of its possible involvement in human diseases involving genetic alteration at these chromosomal regions. 相似文献
97.
Diofantos G. Hadjimitsis Marinos G. Hadjimitsis Chris Clayton Brian A. Clarke 《Water Resources Management》2006,20(3):449-465
Determination of turbidity is a common component of water-quality assessments. In regions where there are a lot of inland
waters such as dams, sampling even a small proportion of those dams for monitoring and assessing water quality is cost prohibitive.
Satellite remote sensing has the potential to be a powerful tool for assessing water quality over large spatial scales. The
overall objective of this study was to examine whether Landsat-5 TM (Thematic Mapper) and Landsat-7 ETM+ (Enhanced Thematic
Mapper) could be used to measure turbidity across theKourris Dam, which is the biggest dam in Cyprus. This paper presents
the results obtained by applying the linear regression analysis in order to examine the relationship between the turbidity
measurements measured in-situ during the satellite overpass against at-satellite atmospheric corrected reflectance values.
It has been found that the reflectance, after atmospheric correction, at LandsatTMBands 1 and 3 is strongly related with turbidity
levels after linear regression analysis. The most significant correlation was occurred when reflectance in TM band 3 and logarithmic
reflectance in TM band 3 were correlated with turbidity measurements. Indeed, the correlation coefficient (R) when atmospheric
corrected reflectance (ρ) in the LandsatTMband 3 were correlated against turbidity, before atmospheric correction was R =
0.38 and after atmospheric correction was R = 1; and when atmospheric corrected logarithmic reflectance (Log ρ) in the Landsat
TM band 3 were correlated against turbidity, before atmospheric correction was R = 0.46 and after atmospheric correction was
R = 1. 相似文献
98.
99.
M Garofalo R Borioni A Penta Peppo GM Actis Dato P Tempesta L Chiariello 《Canadian Metallurgical Quarterly》1995,37(4):202-203
Femoral artery lesions may occur after cardiac catheterization or percutaneous transluminal coronary angioplasty (PTCA). The incidence of pseudoaneurysm following transfemoral catheterization ranges from 0.21 to 6.25%. Among 3162 cardiac catheterization procedures thirteen (0.41%) patients presented a femoral pseudoaneurysm requiring surgical repair. The Authors reported their technical consideration about the utility of extraperitoneal iliac control during surgical repair of femoral artery pseudoaneurysm due to cardiac catheterization. 相似文献
100.