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121.
F Espa?a M Martínez J Sánchez-Cuenca CD Vera A Estellés JF Jiménez-Cruz 《Canadian Metallurgical Quarterly》1996,30(4):512-518
OBJECTIVE: To improve the specificity and sensitivity of the prostate-specific-antigen (PSA) assay for the distinction between prostate cancer and benign prostate hyperplasia (BPH). METHODS: Two sensitive immunoassays, one that measures free PSA and PSA complexed to alpha 1-antichymotrypsin (alpha 1-ACT) with the same efficiency (PSAag assay) and another that specifically measures the complex between PSA and alpha 1-ACT, have been designed to measure the PSA forms in the plasma of 84 patients with prostate disease and in the seminal plasma from 60 healthy individuals. RESULTS: The proportion of plasma PSA in complex with alpha 1-ACT was significantly higher in the 34 patients with prostate cancer (89 +/- 12%, mean +/- SD; median, 91%) than in the 50 patients with BPH (71 +/- 12%; 73%) and did not correlate with the total amount of PSA. Normal seminal plasma (n = 60) had 2.1 +/- 0.6 mg/ml PSA, 175 +/- 62 microns/ml alpha 1-ACT and 9.6 +/- 3.4 micrograms/ml PSA: alpha 1-ACT complex. CONCLUSION: These results confirm that PSA: alpha 1-ACT may be a good marker for a differential diagnosis of carcinoma of the prostate and BPH. 相似文献
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124.
L. Valade I. Malfant A. Glaria J.-F. Lamère B. Garreau de Bonneval D. de Caro S. Vincendeau K. Jacob M.-L. Doublet A. Zwick 《Journal of Low Temperature Physics》2006,142(3-4):449-452
For the development of new crystal and electronic structures in molecular conductors, dimeric tetrathiafulvalene (TTF) and
tetraselenafulvalenes (TSFs)1–3 linked by single or double methyl antimony bridge(s) have been prepared and their neutral crystal structures have been investigated.
The donor2 (cis-2) forms a metallic cation radical salt with tetracyanoquinodimethane (TCNQ) containing one-dimensional array interactions. 相似文献
125.
126.
The in vitro effect of citric acid application on periodontally involved root surfaces was investigated using scanning electron microscopy. Teeth were selected following specific criteria. The specimens were prepared for observation, and the features of the root surface were studied. The results demonstrated that a 3-minute application of citric acid (pH = 1.0) to the root surface after scaling and root planing demineralized the outer root surface, opened the dentinal tubules, and exposed collagen fibers. Scaling and root planing alone left the surface with a smear layer, scattered islands of cementum, and no collagen fibers or exposed dentinal tubules. 相似文献
127.
Anodic oxidation of mecoprop herbicide at lead dioxide 总被引:1,自引:0,他引:1
The electrochemical oxidation of an aqueous solution containing mecoprop (2-(2-methyl-4-chlorophenoxy)propionic acid) has
been studied at PbO2 anodes by cyclic voltammetry and bulk electrolysis. The influence of current density, hydrodynamic conditions, temperature
and pH on the degradation rate and current efficiency is reported. The results obtained show that the use of PbO2 leads to total mineralization of mecoprop due to the production of oxidant hydroxyl radical electrogenerated from water discharge.
The current efficiency for the electro-oxidation of mecoprop is enhanced by low current density, high recycle flow-rates and
high temperature. In contrast, the pH effect was not significant. It has also been observed that mecoprop decay kinetics follows
a pseudo-first-order reaction and the rate constant increases with rising current density. 相似文献
128.
129.
We present an analysis of a stochastic model of the vascular endothelial growth factor (VEGF) receptor. This analysis addresses the contribution of ligand-binding-induced oligomerization, activation of src-homology 2 domain-carrying kinases and receptor internalization in the overall behaviour of the VEGF/VEGF receptor (VEGFR) system. The analysis is based upon a generalization of a Wentzel-Kramers-Brillouin (WKB) approximation of the solution of the corresponding master equation. We predict that tumour-mediated overexpression of VEGFRs in the endothelial cells (ECs) of tumour-engulfed vessels leads to an increased sensitivity of the ECs to low concentrations of VEGF, thus endowing the tumour with increased resistance to anti-angiogenic treatment. 相似文献
130.
Extended Hyperbolic Model for Sand-to-Concrete Interfaces 总被引:1,自引:0,他引:1
Jesús E. Gómez George M. Filz Robert M. Ebeling 《Canadian Metallurgical Quarterly》2003,129(11):993-1000
A relatively simple, four-parameter extended hyperbolic model for interfaces was developed for use in soil-structure interaction analyses. The model accommodates arbitrary stress path directions and includes three important elements: (1) development of a yield surface during interface shear; (2) a formulation for yield-inducing shear stiffness that is applicable to any stress path orientation; and (3) a formulation for unloading-reloading shear stiffness. The model was evaluated against the results of shear tests performed at the interface between three different types of sand and a concrete surface under a variety of stress paths. Comparisons between measured and calculated interface response indicate that the model provides accurate estimates of the response of sand-to-concrete interfaces. 相似文献