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1.
The tumour necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6) mRNA accumulation and the release of the cytokines TNF-alpha and IL-6 was determined in leukemic cells isolated from bone marrow biopsy from patients with acute lymphoblastic leukemia: ALL-common type (cALL), 11 patients; ALL-T type, nine patients. The non-leukemic bone marrow cells (BMMC) and peripheral blood mononuclear cells (PBMC) from healthy donors were used as a control. The mRNA was assessed by fluorescent in situ hybridization in cell suspension and analyzed with flow cytometry. The accumulation of cytokine mRNA was higher in cALL cells as compared to ALL-T and PBMC (control) and was comparable to cytokines mRNA accumulation in BMMC. The production of IL-6 by leukemic cells from both types of leukemia was significantly lower than in BMMC. The bioactive TNF was not detected in either of the leukemia groups studied. TNF-alpha protein was produced by ALL-T cells and BMMC but not by cALL type of leukemic cells. The synthesis of IL-6 was significantly enhanced by TNF-alpha in BMMC and ALL-T while the presence of TNF-alpha had no effect on IL-6 synthesis in the culture of cALL leukemic cells. It was concluded that despite IL-6 and TNF-alpha mRNA contents, leukemic cells representing early stage of B-cell development (CD10+) showed disregulation of production of these cytokines.  相似文献   
2.
The random sequential adsorption (RSA) approach was used for modelling irreversible adsorption phenomena of polyatomic particles at homogeneous interfaces. Particles of spherical and spheroidal shape, characterised by various axis ratio parameter A, were considered. In the latter case, the flat (side-on) and unoriented adsorption was discussed. The sticking probability (available surface function) was determined for various particle shapes together with “jamming” coverages for clean and precovered surfaces. The structure of adsorbed particle monolayers (under transient and jammed states) was analysed quantitatively in terms of the pair correlation functions. Methods of extrapolation of these results to interacting (soft) particle systems were also discussed. The theoretical predictions were confronted with existing experimental results derived for monodisperse spherical particles. A good agreement with theory was found both in respect of jamming coverages and the monolayer structure. These theoretical and experimental studies demonstrated that minor amounts of small particles (nanometer size range) exert decisive influence on adsorption of larger particles. This phenomenon can be treated as analogous to the surface poisoning effect occurring in heterogeneous catalytic systems. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
3.
The cesium salts Cs x H3?x PW12O40 of Cs content x = 2 up to x = 3 were tested as the catalysts in the gas and liquid phase reactions. Dehydration of ethanol and transesterification of triglycerides with methanol were selected as the catalytic reactions. Apart from the standard preparation, the catalysts were prepared by two-stage procedure with methanol or water as a solvent. The Cs-salts were characterized by FT-IR, XRD, scanning electron microscopy and energy dispersive X-ray techniques. In turn, the influence of Cs-salts composition on the pH and conductivity of their aqueous colloidal solutions was investigated. The results obtained by the latter techniques were also characteristic for acidity of surface layer of colloidal particles because of surface layer-solution equilibrium. It has been shown that the secondary structure of acidic cesium salts existing in crystalline samples (solid solution of H3PW12O40 in Cs3PW12O40) changes after contacting with polar medium to the system consisting most probably of Cs3PW12O40 core with epitaxial layer of heteropolyacid. This is result of the protons migration from bulk to surface layer of primary particles enhanced by polar medium. It strongly influences the surface acidity of primary particles as well as the activity of Cs-salts in transesterification of triglycerides with methanol. In such polar medium, Cs2HPW12O40 salt becomes the most active catalyst, more active than Cs2.5H0.5PW12O40. An accumulation of partial glycerides and in particular glycerol on the surface of primary particles of Cs-salts resulted in relatively low maximum conversion of triglycerides, most probably due to partial blockage of the catalytic centers. This effect and the almost constant activity of Cs-salts under recycling use in the transesterification experiments are considered to be experimental evidences that methanolysis over Cs-salts was accomplished with the participation of surface protons.  相似文献   
4.
S. Ng  P. Warszynski  M. Zembala  K. Malysa   《Minerals Engineering》2000,13(14-15):1519-1532
Size, rise velocity, shape, and composition of bitumen-air aggregates floating to the froth layer during the processing of 11.1% bitumen Estuarine ore, and 7.2% bitumen Marine ore under various operating conditions (caustic dosage and feed density) were determined. The flux of the bitumen-air aggregates inside a Primary Separation Vessel (PSV) processing 2 tonnes/hour of the ore was in-situ monitored and video recorded. The mass of bitumen contained in the aggregates floating to the froth layer under different operating conditions was calculated on the basis of the measured rise velocities and dimensions of the aggregates. It was found that the type of ore processed was the parameter having the largest effect on size and composition of the bitumen-air aggregates floating to the froth layer inside the PSV during a 50°C warm slurry extraction process. In the case of the Estuarine ore the average mass of bitumen contained in an average aggregate was ca. 9*10−4 g, and the average aggregate size was ca. 1.0 mm. During processing of the low grade (Marine) ore the aggregates were smaller (within 0.33–0.69 mm) and they carried much less (from 0.17–1.37*10−4 g) bitumen, depending on other operating conditions (caustic dosage and feed density). A good correlation between size of the bitumen-air aggregates and bitumen recovery in the primary separation vessel was found. Thus, size of the aggregates can be used as an indication of better flotation recovery.  相似文献   
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6.
The photodynamic effect of Victoria blue BO (VB-BO) and photoirradiation on peripheral blood mononuclear cells was studied. The cells were preincubated with VB-BO followed by photoirradiation and overnight culture. The highest percentage of dead cells (propidium iodide assay in flow cytometry) was seen in the monocyte population. The lymphocytes showed a lower sensitivity to VB-BO photodynamic action than the monocytes (12% vs 80% of PI-positive cells). The effect of VB-BO and phototreatment on lymphocyte function was studied using a mitogen-induced proliferation assay. A decrease of mitogen response was observed. The VB-BO and photoirradiation were also used on leukemic cells. The leukemic cells from acute myeloid leukemia and B precursors leukemia were sensitive to VB-BO photodynamic action. The high VB-BO sensitivity of monocytes and leukemic cells (myeloid and lymphoid B derived) suggests possible application of VB-BO for selective depletion of monocytes or sensitive leukemic cells.  相似文献   
7.
OBJECTIVES: Previous reports indicate that up to 10% of patients with localized renal cell carcinoma have direct intracaval neoplastic extension. Many patients with locally confined tumors and small intracaval tumor extensions can be surgically cured. Few studies have documented long-term survival after radical surgery for renal cell carcinoma involving higher vena caval tumor extension. We report the follow-up of 34 consecutive patients undergoing radical nephrectomy and intrahepatic or supradiaphragmatic intracaval thrombectomy for renal cell carcinoma. METHODS: From October 1982 through January 1993, 34 consecutive patients with a mean age of 60 years were identified as having clinical Stage T3 renal cell carcinoma (mean diameter 9.5+/-4.0 cm) with intrahepatic (41%) or supradiaphragmatic (59%) intracaval neoplastic extension. Patients underwent radical nephrectomy with intrahepatic caval thrombectomy (38%) or supradiaphragmatic caval thrombectomy using cardiac bypass with hypothermia and circulatory arrest (62%). Clinical outcome was assessed during a mean follow-up of 30 months (range 1 to 182). RESULTS: A total of 24 (71%) of 34 tumors demonstrated capsular penetration, and 22 (65%) of 34 had significant perinephric extension into Gerota's fascia by pathologic analysis. Metastatic disease was identified in 35% of patients either at the time of surgery or by pathologic analysis. Using Kaplan-Meier actuarial analysis, the likelihood of survival for all 34 consecutive patients after surgery was 68% (95% confidence interval [CI] 49% to 81%) at 1 year, 32% (95% CI 18% to 48%) at 2 years, 14% (95% CI 5% to 28%) at 5 years, and 9% (95% CI 2% to 24%) at 10 years. Neither capsular penetration, perinephric extension, the level of intracaval extension of tumor, nor the use of cardiopulmonary bypass significantly affected survival. CONCLUSIONS: In patients with renal cell carcinoma and intrahepatic or supradiaphragmatic intracaval extension of tumor, the presence of metastases is a frequent occurrence and, if present, greatly diminishes survival. Improvements in the preoperative detection of occult metastases are needed if surgery alone is to improve survival.  相似文献   
8.
Autonomic impairment is associated with poor prognosis in many diseases. The pathogenesis of the uremic autonomic neuropathy has not been convincingly established, so the article reviews available information on factors involved in its development, furthermore the authors put forward their own hypothetical scheme of the pathogenesis. The last section outlines the methods most commonly used for its diagnosis and finally the authors discuss symptoms suggestive of this neuropathy in clinical setting.  相似文献   
9.
We report the construction of two cloning vectors that are based on the Pseudomonas-Escherichia shuttle vector, pUCP19. The new vectors, pUCPKS and pUCPSK, contain a significantly expanded multiple cloning site (MCS) with an adjacent T7 promoter sequence. In conjunction with specifically engineered host strains encoding an inducible T7 RNA polymerase, these vectors allow the controlled production of plasmid-encoded proteins in both Escherichia coli and Pseudomonas aeruginosa to analyse the spectrum of products encoded by cloned segments of DNA. The usefulness of these vectors was demonstrated by expressing the chloramphenicol acetyltransferase (CAT)-encoding gene.  相似文献   
10.
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