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1.
A new method for the solution of the damped Burgers' equation is described. The marker method relies on the definition of a convective field associated with the underlying partial differential equation; the information about the approximate solution is associated with the response of an ensemble of markers to this convective field. Some key aspects of the method, such as the selection of the shape function and the initial loading, are discussed in some details. The marker method is applicable to a general class of nonlinear dispersive partial differential equations. © 2005 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2006  相似文献   
2.
In this paper we study a free boundary problem modelling the growth of nonnecrotic tumors. The main trait of this free boundary problem is that it is essentially multidimensional, so that its well-posedness is hard to establish by using the usual methods in the classical theory of free boundary problems. In this paper we use the functional analysis method based on the theory of analytic semigroups to prove that this problem has a unique local solution in suitable function spaces. Continuous dependence of the solution on the initial data and regularities of the solution can also be easily obtained by using the argument of this paper.  相似文献   
3.
Zheng YF  Xu GW  Liu DY  Xiong JH  Zhang PD  Zhang C  Yang Q  Lv S 《Electrophoresis》2002,23(24):4104-4109
Thirteen normal and modified nucleosides, primarily degradation products of transfer ribonucleic acid (tRNA), were evaluated as potential tumor markers for cancer patients. Their urinary concentrations were determined by means of micellar electrokinetic capillary chromatography (MEKC) in the urine from 54 healthy adults and 70 cancer patients, then quantitatively expressed as a function of creatinine excretion. It was found that urinary nucleosides for cancer patients were on the average significantly higher than those for healthy controls, however, no significant differences were found between male and female or between different ages. Based on 13 urinary nucleoside concentrations, principal component analysis (PCA) could be used to classify 72% of cancer patients from the healthy controls. The present study shows that the precise measurement of urinary nucleosides by MEKC in combining with PCA technique may provide a clinically useful approach for diagnosis of cancer.  相似文献   
4.
Cytochrome-c detection   总被引:2,自引:0,他引:2  
Following a myocardial infarction (MI) cells die or are damaged and their contents leak into the blood circulation, resulting in elevated serum levels of various enzymes, proteins, and organic molecules. Over the past few decades, it has become standard practice to employ the detection of these elevated substances as markers for the confirmation of MIs and to monitor MI patients’ response to treatment. Although it has previously been shown that cytochrome-c, a small respiratory protein, is among those elevated, the lack of a suitable detection system has prevented its routine use in the diagnosis of MIs. We present a preliminary study in which chemiluminescence was employed to detect elevated levels of cytochrome-c in the serum of MI patients. The technique, which is specific for c-type proteins, is approx 30 times more sensitive than the traditional Coomassie blue stain and can detect as little as 0.03 μg of protein. It also has potential for diagnostic use in other diseases that are characterized by mitochondrial damage.  相似文献   
5.
The gold nanoprisms (GNPs) have exhibited special plasmonic properties for biomedical applications because of their unique shapes and dimensions. Based on their optical performance, the NIR dye IR780 not only enabled the GNPs-based nanosystem as SERRS nanoparticles for Raman-encoded molecular imaging, but also enhanced the plasmonic photothermal property by laser irradiation. Meanwhile, the GNPs/IR780-Lyp-1 by introduction of tumor-homing peptide segment LyP-1, which presents high affinity to p32 protein, demonstrated the increased enrichment in tumor region and enhanced photothermal therapy efficacy.  相似文献   
6.
In the present era, a major drawback of current anti-cancer drugs is the lack of satisfactory specificity towards tumor cells. Despite the presence of several therapies against cancer, tumor homing peptides are gaining importance as therapeutic agents. In this regard, the huge number of therapeutic peptides generated in recent years, demands the need to develop an effective and interpretable computational model for rapidly, effectively and automatically predicting tumor homing peptides. Therefore, a sequence-based approach referred herein as THPep has been developed to predict and analyze tumor homing peptides by using an interpretable random forest classifier in concomitant with amino acid composition, dipeptide composition and pseudo amino acid composition. An overall accuracy and Matthews correlation coefficient of 90.13% and 0.76, respectively, were achieved from the independent test set on an objective benchmark dataset. Upon comparison, it was found that THPep was superior to the existing method and holds high potential as a useful tool for predicting tumor homing peptides. For the convenience of experimental scientists, a web server for this proposed method is provided publicly at http://codes.bio/thpep/.  相似文献   
7.
In this paper, a tumor immune model with time delay is studied. First, the stability of nonnegative equilibria is analyzed. Then the time delay τ is selected as a bifurcation parameter and the existence of Hopf bifurcation is proved. Finally, by using the canonical method and the central manifold theory, the criteria for judging the direction and stability of Hopf bifurcation are given.  相似文献   
8.
探讨了血清、头发中Cu、Zn及Cu/Zn比值对肺癌、肝癌及胃肠道肿瘤的诊断价值,检测了171例样品,并与156名健康者进行对比研究.结果显示血清和头发Cu、Cu/Zn可作为恶性肿瘤的筛选指标,发Cu、Cu/Zn有助于肺癌临床分期,血清Cu有助于肝癌诊断和预示进展程度,而Cu/Zn可能对胃肠道肿瘤的诊断和预后更有用.  相似文献   
9.
水溶性金属卟啉肿瘤靶向磁共振成像造影剂的研究   总被引:5,自引:0,他引:5  
利用显微荧光-阿达玛变换三维图像分析研究了Cu-TSPP,Mn-TSPP,Cu-TMAP,Mn-TMAP4种水溶性金属卟啉人细胞间质进入肿瘤细胞内的富集过程,对金属卟啉的自旋-晶格驰豫性能(R1)的天空结果表明,Mn(Ⅱ)卟啉配合物的R1、值结Gd-DTPA提高1.5-2倍。  相似文献   
10.
《Electroanalysis》2003,15(3):225-229
The interaction between avidin and biotin was evaluated electrochemically by monitoring the change in the electrode response of redox markers. Biotin was immobilized on the electrode surface by means of the electrochemical polymerization of biotinylated pyrrole and pyrrole. When avidin was introduced onto the biotinylated polypyrrole electrode surface, the large change in the electrode response of the redox marker was detected. The fact that the change in the electrode response of a marker ion could be attributed to the electrostatic interaction between avidin on the electrode surface and the redox marker ion present in a solution was verified by replacing avidin with NutrAvidin. At a pH lower than the isoelectric point of avidin, the electrode response of ferrocyanide as an anionic marker ion increased linearly within the range of 5.0×10?9 ?3.0×10?8 M avidin. The relative standard deviation at 1.5×10?8 M avidin was about 5.4% (n=5). The detection of biotin was also performed using a competitive reaction between biotin in solution and biotin that had been immobilized on the electrode surface in the form of the biotinylated polypyrrole.  相似文献   
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