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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
S Bastian JL Paquet C Robert B Cremers B Loillier JF Larrivée DR Bachvarov F Marceau D Pruneau 《Canadian Metallurgical Quarterly》1998,253(3):750-755
Near-haploidy is a rare cytogenetic finding in childhood acute lymphoblastic leukaemia (ALL) and is associated with a poor prognosis. A second hyperdiploid line, occurring presumably by endoreduplication of the near-haploid stemline, is often observed. We present a case of common ALL in relapse characterized morphologically by a dual population of small and large lymphoblasts. Cytogenetic analysis supplemented with fluorescence in-situ hybridization (FISH) studies localized near-haploidy and hyperdiploidy to the small and large blast population respectively. DNA ploidy determination confirmed two abnormal clones with near-haploidy as the predominant one. A novel t(9;12)(q11;q13) was present in the near-haploid clone and was duplicated in the hyperdiploid clone. This finding identified cells bearing near-haploidy to be the clonogenic population following malignant transformation and confirmed endoreduplication as the mechanism for the presence of associated hyperdiploidy. 相似文献
993.
B López-Romero G Evrard F Durant M Sevrin P George 《Canadian Metallurgical Quarterly》1998,6(10):1745-1757
X-ray diffraction and ab initio MO theoretical calculations were used in order to investigate the structural and electronic properties of sarmazenil, a weak inverse agonist at the omega modulatory sites (benzodiazepine receptors). This compound was compared to bretazenil, a partial agonist, and to the antagonist flumazenil on the basis of structural and electronic data. The conformational and theoretical properties (interatomic pi overlap populations, molecular electrostatic potential (MEP), the topology of frontier orbitals, and proton affinity) of these three imidazobenzodiazepinones were determined in order to analyse the stereoelectronic properties in relation with their distinct intrinsic efficacies at the omega modulatory sites. 相似文献
994.
B. Meng 《Materials and Structures》1996,29(4):195-205
A knowledge of fractal properties of the pore system is extremely useful with regard to the interrelationships between moisture transport and pore structure. The fractal dimension characterises the egree of resolutiondependence of a property. Given a completely interlaced pore system such as that of sandstone, the fractal dimension of the pore volume, or the porosity, quantifies the cross-sectional variability of the pore channels and is thus of great relevance with regard to transport processes. The fractal dimension of the pore surface describes the surface roughness. A newly-developed measuing technique is presented for the simultaneous determination of fractal dimensions of porosity and pore surface and for establishing fraction radii distributions in order to derive relevant parameters for moisture transport. 相似文献
995.
996.
A Elhage S Vanderstichele E Leblanc B Castelain D Querleu 《Canadian Metallurgical Quarterly》1996,24(11):830-833
Total abdominal hysterectomy and bilateral salpingo-oophorectomy has long been the standard surgical treatment for endometrial cancer. Radical hysterectomy is not useful in stage I. in women with extreme obesity and medical risk factors, vaginal hysterectomy is recommended. Laparoscopy-assisted vaginal hysterectomy complete the oncologic treatment if lymphadenectomy is necessary. 相似文献
997.
B. Wu P.L. Chu 《Photonics Technology Letters, IEEE》1996,8(2):230-232
We report an experimental investigation of the fast optical switching in a Sm/sup 3+/-doped fiber. We discovered that this fiber can effect a fast switching speed less than 5 ns. However, the required switching power is 472 W with pulsewidth 10 ns. 相似文献
998.
Summary The magnetohydrodynamic (MHD) boundary layer flow over a flat plate is examined here for two cases, viz. a uniform free-stream velocity and a uniform hydrostatic pressure. The nonlinear boundary layer equations are solved using a reliable finite-difference method. The boundary layer physical parameters such as skin-friction coefficient, displacement, momentum and energy thicknesses of the boundary layer are determined. It is found that the normal surface velocity gradient decreases with the local magnetic interaction parameter for the cases of a uniform hydrostatic pressure, whereas in the case of a uniform free-stream volocity it increases with the interaction parameter. 相似文献
999.
The fabrication, properties and composition of heated phosphate-bonded clay bricks are reported. The strength of phosphate-bonded clay bodies is shown to be related to the equilibrium pH of the clay mix. The highest strengths were obtained for mixes with equilibrium pH 7 fired at 500°C which gave a modulus of rupture 60% higher than the unmodified clay heated under similar conditions but at 800°C firing temperature. The phosphate-bonded products were also of low porosity and improved dimensional stability. An insight into the probable mechanism of strength development of the heated product has been obtained from XRD, SEM and DSC studies. The results show that the properties of the phosphate-bonded clay bodies are critically affected by new mineral phases resulting from the reactions of phosphates with clay which subsequently undergo physico-chemical changes above 550°C. 相似文献
1000.
Z Zdrojewski A Raszeja-Specht J Kustosz A Skibowska B Rutkowski 《Canadian Metallurgical Quarterly》1996,53(5):434-438
Platelets (PLT) play an important role in hemostasis, modulation of immunological and inflammatory processes. There is also evidence that PLT takes part in the development of atherosclerosis and glomerulosclerosis. The aim of presented study was to determine morphological and functional changes of platelets and their relation to the lipid, protein and coagulation factors disturbances in patients with chronic glomerulonephritis (CGN). The studies were carried out in 60 patients with CGN diagnosed by renal biopsy: 30 patients without nephrotic syndrome (NS)-CGN and 30 patients with NS-CGN+NS. Protein and lipid disturbances, coagulation factors were estimated using routine laboratory methods. Platelet count (PLT), mean platelet volume (MPV) and modal platelet volume (PLT-Mode) were measured using Technicon H1 hematological autoanalyser. Platelet function was assessed by aggregometry using turbidimetric method (inductors: ADP 1-3 microM, collagen 50g/ml, epinephrine 0.25-5 microM). Spontaneous platelet aggregation (SPA) was measured in platelet rich plasma (PRP) without inductors for 15 min, in 1-2 hours after venesection. SPA was observed in 9 of 30 patients with CGN and in 19 of 30 patients with CGN+NS. MPV and PLT Mode were significantly higher in patient showing SPA compared with those without. Significant correlations between SPA and the concentration of plasma albumin (r = -0,70; p < 0.02) TG and CH-LDL (r = 0,61; p < 0.05) were found in CGN+NS patients. APTT was significantly shorter in patients showing SPA compared with those without and negative significant correlation between SPA and APTT was found. Platelet aggregation to inductors in CGN and CGN+NS patients was diminished compared with control group. Lack of second phase aggregation in response to aggregation inducers was observed in patients with SPA. Conclusions. 1. Platelet hyperaggregation play an important role in hypercoagulation state in CGN patients. 2. SPA in vitro was observed in majority of CGN+NS patients and in some without NS. 3. Pathomechanism of SPA is probably multifactorial (hypoalbuminemia, dyslipidemia, changes in concentration of coagulation parameters). 相似文献