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991.
The clinical, haematological and cytogenetic data for 20 patients with an acquired abnormality of 11q23 and 10p have been reviewed at this workshop. Patients predominantly presented with de novo AML M5a and the most common cytogenetic finding was an inversion of part of the long arm of chromosome 11 followed by a translocation between 11q and 10p. Band p12 represented the most common breakpoint on chromosome 10. The t(10;11) subgroup defined a subset of younger 11q23 patients, the majority of whom achieve a first complete remission despite the differing treatment regimens.  相似文献   
992.
993.
With exception of ZrO2, the individual oxides and binary compositions in the system Al2O3–Cr2O3–TiO2 are the most important oxide materials for the preparation of thermally sprayed coatings. In this contribution selected results of recent own research activities are summarized. This includes the comparison of microstructures, phase compositions, and properties of coatings, deposited by atmospheric plasma spraying (APS) and high velocity oxy‐fuel (HVOF) spraying. The possibilities arriving from the use of suspensions as feedstock are reviewed. Special attention is paid to the advantage of use of binary compositions in this system. Tribological, electrical and corrosion properties of the coatings are discussed.  相似文献   
994.
995.
Lifetime Prediction of Plastic Pipes by means of Internal Pressure Creep Test The Lifetime Prediction of plastic pipes is based, according to the current set of relevant technical regulations, mainly on the Internal Creep Rupture Test. In this examination, the test for the pipes performed in an accelerated mode with a defined internal pressure and at increased temperatures. In compliance with the applicable Arrhenius rate law, an extrapolation of the measured values then takes place.  相似文献   
996.
Broad-range PCR has proven to be useful for the detection of bacteria. A set of broad-range PCR primers directed against conserved regions in the 16S rRNA gene was designed to specifically amplify either gram-positive or gram-negative bacteria. The gram type-specific broad-range PCR correctly classified all 62 pathogenic species tested.  相似文献   
997.
Background and Aims: A 3‐year study was carried out in order to evaluate the ecophysiology, yield and quality characteristics of Vitis vinifera L. cv. Kékfrankos (syn. Limberger) at Eger‐Nagyeged hill (steep slope) and at Eger‐K?lyuktet? (flat) vineyard sites located in the Eger wine region, Hungary. The aim of this paper was to analyse the effect of ‘vintage’ and ‘terroir’ on the seasonal changes of Kékfrankos ecophysiology and its possible relationship with yield and wine composition. Methods and Results: Grapevine physiological responses (midday‐ and pre‐dawn water potential, pressure–volume analysis and gas‐exchange), growing stages, yield and wine composition of each vineyard were studied. Lower grapevine water supply was detected at Eger‐Nagyeged hill in each season due to its steep slope and soil characteristics. Pressure‐volume curves indicated that there was no osmotic adjustment in the leaves of this variety. Higher osmotic concentration was measured at turgor loss and full turgor in the leaves of the unstressed vineyard (Eger‐K?lyuktet?) presumably due to higher photosynthetic activity. Differences in soil water content of the vineyards resulted in a slightly altered cell wall elasticity. Stomatal conductance, transpiration rate and photosynthetic production per unit leaf area were affected by water availability. Lower yield in Eger‐Nagyeged hill was partly associated with decreased photosynthetic production of the canopy. Improved wine quality of Eger‐Nagyeged hill was due to moderate water stress which induced higher concentration of anthocyanins and phenolics in the berries. The duration of the phenological stages was dependent on vintage temperature characteristics rather than on vineyard site. Conclusion: There was a close relationship between environmental conditions, Kékfrankos gas‐exchange, water relations, yield and wine composition. Water deficit plays an important role in creating a terroir effect, resulting in decreased yield, better sun exposure of leaves and clusters and thus higher concentration of phenolics and anthocyanins. Although quality is mainly influenced by vintage differences, vineyard characteristics are able to buffer unfavourable vintage effects even within a small wine region. Significance of the Study: Stomatal conductance, pre‐dawn water potential and climatic data may be reliable parameters for terroir classification, although variety–terroir interactions must always be considered.  相似文献   
998.
Some of the deepest structural slurry walls in the world were designed for permanent training walls at the Dam No. 2 Hydropower Project on the Arkansas River. Each of the 152 wall panels had to be optimized for embedment, length, section type, and restraining system. Compatibility for deflection and load transfer of adjacent panels was an integral part in designing individual structural slurry wall panels to behave as a system of panels. Design of the structural slurry walls utilized the computer program RIDO to analyze the deflection, shear, and moment under construction and operation conditions. Structural requirements for the design based on the RIDO analyses were checked using STAAD-III. A third program (SOILSTRUCT) was used to verify the 2D global deformation of the proposed structural slurry wall system. Analyses and design had to be completed in a short 9-month time frame. This paper presents the design methodology, approach, and procedures for optimization of the structural slurry wall system required to make this project a reality.  相似文献   
999.
Interactions of human immunodeficiency virus type 1 (HIV-1) with hematopoietic stem cells may define restrictions on immune reconstitution following effective antiretroviral therapy and affect stem cell gene therapy strategies for AIDS. In the present study, we demonstrated mRNA and cell surface expression of HIV-1 receptors CD4 and the chemokine receptors CCR-5 and CXCR-4 in fractionated cells representing multiple stages of hematopoietic development. Chemokine receptor function was documented in subsets of cells by calcium flux in response to a cognate ligand. Productive infection by HIV-1 via these receptors was observed with the notable exception of stem cells, in which case the presence of CD4, CXCR-4, and CCR-5, as documented by single-cell analysis for expression and function, was insufficient for infection. Neither productive infection, transgene expression, nor virus entry was detectable following exposure of stem cells to either wild-type HIV-1 or lentivirus constructs pseudotyped in HIV-1 envelopes of macrophage-tropic, T-cell-tropic, or dualtropic specificity. Successful entry into stem cells of a vesicular stomatitis virus G protein-pseudotyped HIV-1 construct demonstrated that the resistance to HIV-1 was mediated at the level of virus-cell membrane fusion and entry. These data define the hematopoietic stem cell as a sanctuary cell which is resistant to HIV-1 infection by a mechanism independent of receptor and coreceptor expression that suggests a novel means of cellular protection from HIV-1.  相似文献   
1000.
We derive an expression for the temporal fractional Talbot effect in delay lines with arbitrary orders of dispersion. We then demonstrate, experimentally and by numerical simulations, that a simple device consisting of a number of uniform fiber Bragg gratings or of waveguides can serve for such a tailored dispersive delay line for periodic optical pulses. The device produces temporally delayed and phase-shifted replicas of the original pulses, similarly to what happens in dispersive delay lines in the fractional Talbot effect. Such devices can be useful for compensation for the nonquadratic spectral phase of diode lasers, of dispersive elements in systems used for temporal imaging, real-time spectral analysis, and periodic pulse generation.  相似文献   
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