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1.
Serum samples from endometrial cancer (EC) patients and healthy females were analyzed using surface-enhanced laser desorption-ionization time-of-flight mass spectrometry (SELDI-TOF-MS) to discover the potential diagnostic biomarker for detection of EC. A preliminary training set of spectra derived from 40 E C patients and 30 healthy women were used to develop a proteomic model that effectively discriminated cancer patients from healthy women. The training set had a specificity of 100% and sensitivity of 92.5% in the EC detection. A blind test set, including 20 new cancer cases and 10 healthy women, was used to validate the sensitivity and specificity of this multivariate model, which had a corresponding results of 60% in specificity and 75% in sensitivity, respectively. The combination of SELDI-TOF-MS with bioinformatics tools could help find new biomarkers and establish the detection of EC with high sensitivity and specificity.  相似文献   

2.
We developed a special methylene blue solution for staining of cervix shedding cells based on catalytic oxidizing chromogenic reaction, which shows a potential for cervical cancer cytology screening. We screened a total of 1 922 women for cervical cancer with the special methylene blue staining method and a conventional Pap smear method using cervix shedding cells. Then, the patients with positive indicators of the Pap smear or this special solution staining method were examined by the electron colposcopy and histopathological examination. Staining of cervical exfoliated cells with this reactive oxygen-based special solution showed that the number of positive cases was 140(7.28%). Among them, 21 cases showed dark green(1.09%), and 119 cases showed purple black(6.19%). The results of the Pap smear method showed that the number of positive cases was 123(6.40%), of which ASCUS was 105(5.46%), ASC-H was 5(0.26%), and LSIL was 9(0.47%), and HSIL was 4(0.21%). For cervical exfoliated cell special staining solution for screening cervical intraepithelial neoplasia(CIN-Ⅱ, CIN-Ⅲ) and cervical cancer, sensitivity was 83.33%, specificity was 65.52%, accuracy was 74.29%, missed diagnosis rate was 13.33%, positive coincidence rate was 51.43%, and the negative coincidence rate is 86.67%. Our results proved the value of this method for early screening of cervical cancer through clinical practice in China.  相似文献   

3.
In the present investigation, magnetic separation studies using an induced roll magnetic separator were conducted to beneficiate low-grade ferruginous manganese ore. The feed ore was assayed to contain 22.4% Mn and 35.9% SiO2, with a manganese-to-iron mass ratio (Mn:Fe ratio) of 1.6. This ore was characterized in detail using different techniques, including quantitative evaluation of minerals by scanning electron microscopy, which revealed that the ore is extremely siliceous in nature and that the associated gangue minerals are more or less evenly distributed in almost all of the size fractions in major proportion. Magnetic separation studies were conducted on both the as-received ore fines and the classified fines to enrich their manganese content and Mn:Fe ratio. The results indicated that the efficiency of separation for deslimed fines was better than that for the treated unclassified bulk sample. On the basis of these results, we proposed a process flow sheet for the beneficiation of low-grade manganese ore fines using a Floatex density separator as a pre-concentrator followed by two-stage magnetic separation. The overall recovery of manganese in the final product from the proposed flow sheet is 44.7% with an assay value of 45.8% and the Mn:Fe ratio of 3.1.  相似文献   

4.
Objective: To develop a new bioinformatic tool based on a data-mining approach for extraction of the most informative proteins that could be used to find the potential biomarkers for the detection of cancer. Methods: Two independent datasets from serum samples of 253 ovarian cancer and 167 breast cancer patients were used. The samples were examined by surfaceenhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS). The datasets were used to extract the informative proteins using a data-mining method in the discrete stationary wavelet transform domain. As a dimensionality reduction procedure, the hard thresholding method was applied to reduce the number of wavelet coefficients. Also, a distance measure was used to select the most discriminative coefficients. To find the potential biomarkers using the selected wavelet coefficients, we applied the inverse discrete stationary wavelet transform combined with a two-sided t-test. Results: From the ovarian cancer dataset, a set of five proteins were detected as potential biomarkers that could be used to identify the cancer patients from the healthy cases with accuracy, sensitivity, and specificity of 100%. Also, from the breast cancer dataset, a set of eight proteins were found as the potential biomarkers that could separate the healthy cases from the cancer patients with accuracy of 98.26%, sensitivity of 100%, and specificity of 95.6%. Conclusion: The results have shown that the new bioinformatic tool can be used in combination with the high-throughput proteomic data such as SELDI-TOF MS to find the potential biomarkers with high discriminative power.  相似文献   

5.
Cancer diagnosis and treatment are of great interest due to the high death rate of cancer.To improve the cure rates of cancer,a diagnostic tool which can detect and treat cancer at initial stages is great needed.Laser-induced fluorescence(LIF) is an adequate analytical technique with advantages of high sensitivity,low sample consumption,short testing time,and suitable for in situ testing.Therefore,it has become one of the most widely used spectroscopic methods for cancer in vivo diagnosis in recent years.This review mainly focuses on the applications of in vivo LIF to distinguish premalignant,malignant from normal tissues in a variety of organ systems,such as lung breast,colon,cervix,esophagus,and bronchus.The potential influence factors for cancer diagnostics and the subsequent suitability of the method to different applications are well discussed.Meanwhile,the technical merits and weaknesses of the LIF technology for cancer diagnosis are also evaluated.Furthermore,different exogenous fluorophores,endogenous fluorophores,and fluorophores synthesized in the tissue are compared on their active principle and effect contrast.The technical potentials of LIF for further development and future applications are also presented as well in this review.  相似文献   

6.
This paper introduces a computerized on-line partial discharge (PD) monitoring and diagnostic system for transformers. The system, which is already in use in a power station, uses wide-band active transducers and a data acquisition unit with modularized and exchangeable components. The system software is a power equipment monitoring and diagnostic system, which is based on the component object model, and was developed for monitoring multiple parameters in multiple power supply systems. The statistical characteristics of PDs in power transformers were studied using 7 experimental models for simulating PDs in transformers and 3 models for simulating interfering discharges in air. The discharge features were analyzed using a 3-D pattern chart with a three-layer back-propagation artificial neural network used to recognize the patterns. The results show that PDs in air and oil can be distinguished. The model can be used for interference rejection on-line monitoring of partial discharge in transformers.  相似文献   

7.
In this study, the effect of simvastatin on the atherosclerotic plaque stability and the angiogenesis in the atherosclerotic plaque of rabbits was observed. Thirty New Zealand rabbits were randomly divided into the normal control group, the model control group and the simvastatin group, 10 in each group. Rabbits in the normal control group were fed with normal forage, while rabbits in the rest two groups were fed with high fat forage. The balloon injury was performed two weeks later to establish an abdominal aortic atherosclerosis model, and then high fat forage was successively fed to them. Meanwhile, simvastatin at the daily dose of 2.5 mg/kg body weight was administered to rabbits in the simvastatin group. After 6 weeks of successive administration, levels of blood lipids were measured after blood sampling, and the serum high sensitivity C-reactive protein (hsCRP) and matrix metalloproteinase-3,-9 (MMP-3,-9) were detected using enzyme-linked immunosorbent assay. The macroscopically pathological indices of the plaque tissue were observed using hematoxylin and eosin (HE) staining of abdominal aorta specimens under a light microscope, and the plaque area (PA), cross-sectional vascular area (CVA) and correcting plaque area (PA/CVA) were determined quantitatively using imaging software. The protein expressions of the vascular endothelial growth factor (VEGF), factor VIII related antigen (FVIIIRAg), MMP-3 and cluster of differentiation antigen 40 ligand (CD40L) in the plaque were detected with the immunohistochemical method. Compared with the model control group, the levels of VEGF, FVIIIRAg, MMP-3, CD40L protein expression and the serum expression levels of hsCRP, MMP-3, MMP-9 in the simvastatin group were significantly reduced (P〈0.05, P〈0.01). The ratio PA/CVA in the simvastatin group was more significantly reduced when compared with that in the model control group (P〈0.01). The levels of serum total cholesterol (TC), triglyceride (TG) and low-density lipoprotein cholesterol (LDL) were significantly reduced in the simvastatin group when compared with those in the model control group (P〈0.05, P〈0.01). Simvastatin plays a certain role in stabilizing the atherosclerotic plaque, and inhibiting the angiogenesis in the atherosclerotic plaque may be one of possible mechanisms.  相似文献   

8.
Better understanding of variations in the mechanical properties of cancer cells could help to provide novel solutions for the diagnosis,prevention,and treatment of cancers.We therefore developed a calculation model of the intracellular elastic modulus based on the contact pressure between the silicon tip of an atomic force microscope and the target cells,and cutting depth.Ovarian cells(UACC-1598) and colon cancer cells(NCI-H716) were cut into sequential layers using an atomic force microscope silicon tip.The cutting area on the cells was 8μm×8μm,and the loading force acting on the cells was increased from 17.523 to 32.126μN.The elastic modulus distribution was measured after each cutting process.There were significant differences in contact pressure and cutting depth between different cells under the same loading force,which could be attributed to differences in their intrinsic structures and mechanical properties.The differences between the average elastic modulus and surface elastic modulus for UACC-1598 and NCI-H716 cells were 0.288±0.08 kPa and 0.376±0.16 kPa,respectively.These results demonstrate that this micro-cutting method can be used to measure intracellular mechanical properties,which could in turn provide a more accurate experimental basis for the development of novel methods for the diagnosis and treatment of various diseases.  相似文献   

9.
fMRI time series analysis based on stationary wavelet and spectrum analysis   总被引:3,自引:0,他引:3  
The low signal to noise ratio (SNR) of functional MRI (fMRI) prefers more sensitive data analysis methods. Based on stationary wavelet transform and spectrum analysis, a new method with high detective sensitivity was developed for analyzing fMRI time series, which does not require any prior assumption of the characteristics of noises. In the proposed method, every component of fMRI time series in the different time-frequency scales of stationary wavelet transform was discerned by the spectrum analysis, then the components from noises were removed using the stationary wavelet transform, finally the components of real brain activation were detected by cross-correlation analysis. The results obtained from both simulated and in vivo visual experiments illustrated that the proposed method has much higher sensitivity than the traditional cross-correlation method.  相似文献   

10.
The enrichment of copper from copper–cyanide wastewater by solvent extraction was investigated using a quaternary ammonium salt as an extractant. The influences of important parameters, e.g., organic-phase components, aqueous pH values, temperature, inorganic anion impurities, CN/Cu molar ratio, and stripping reagents, were examined systematically, and the optimal conditions were determined. The results indicated that copper was effectively concentrated from low-concentration solutions using Aliquat 336 and that the extraction efficiency increased linearly with increasing temperature. The aqueous pH value and concentrations of inorganic anion impurities only weakly affected the extraction process when varied in appropriate ranges. The CN/Cu molar ratio affected the extraction efficiency by changing the distribution of copper–cyanide complexes. The difference in gold leaching efficiency between using raffinate and fresh water was negligible.  相似文献   

11.
A highly sensitive and specific microplate chemiluminescence enzyme immunoassay (CLEIA) was developed for the quantitative evaluation of carbohydrate antigen 72-4 (CA72-4) in human serum, using luminol-H2O2 catalyzed by horseradish peroxidase (HRP) as the chemiluminescence system. The simple and quick determination was accomplished through a sandwich reaction mode. Several physicochemical parameters of the immunoreaction, including incubation conditions, antibody coating conditions, dilution ratio of anti-CA72-4-HRP conjugate, and chemiluminescence reaction time, were studied and optimized. The proposed method exhibited a linear range of 0-200 U/mL with correlation coefficient and detection limit of 0.9995 and 0.18 U/mL, respectively. The inter-assay and intra-assay coefficients of variation (CV) were both less than 10%. The average recovery of two clinical sera with low and high concentration CA72-4 was 99.3% and 98.7%, respectively. Normal tumor markers, including AFP, CEA, CA24-2, CA19-9 and CA15-3, did not cross-react with each other. The method's stability was evaluated by assessing its analytical performance after storing the immunoreagents at 4℃ and 37℃ for 7 days. Little difference was found, indicating satisfactory stability of the method. The present method has been successfully applied to the detection of CA72-4 human serum, and showed a good correlation with the commercially available ELISA kit (r^2=0.9383). This method showed great potential in the fabrication of diagnostic kit for CA72-4, and could be well used in diagnosis of cancer in clinical practice.  相似文献   

12.
PCDD/Fs in the urban air of Dalian,China were monitored with high-volume active sampler from November 2009 to October 2010.The concentration of Cl 4-8 DD/Fs ranged from 3065 to 49538 fg m-3,with an average of 10249 fg m-3.The international toxic equivalents(I-TEQ) value of that was 61.8 1182 fg m-3,with an average of 235 fg m-3,which was comparable to those in the other urban locations around the world.It was found that the Cl 4 8 DD/Fs appeared to be present mainly in the particle phase during winter,spring and autumn,while during summer which were dominantly in gas phase.The ratio of Cl 4-8 DD/Fs present in particle phase increased with the increasing level of chlorination.The concentrations of PCDFs and PCDDs decreased with the increase of chlorinated level,while the concentrations of 2,3,7,8-PCDDs congeners increased with the increase of chlorination level.The homolog profiles of the concentrations of PCDFs presented were higher than those of the PCDDs,which indicated the PCDD/Fs pollution source of the air in Dalian was characteristic for thermal source pollution.The correlation analysis of meteorological parameters with the concentrations of Cl 4-8 CDD/Fs was conducted using SPSS packages,and it was found that the ambient temperature and atmospheric pressure were important factors influence the concentration of PCDD/Fs in the air.The respiratory risk and intake dioxins of the residents around the sampling sites were studied in the paper.It was found that Junge-Pankow model was much more accurate in predicting the gas-particle partitioning behavior of PCDD/Fs homologues during winter,while the Harner-Bidleman model shows better agreement with the measured data during winter and summer.  相似文献   

13.
SQUAMOSA (SQUA) subfamily includes important perianth identity genes of MADS-box gene family. SQUA genes of Dendrocalamus latiflorus were sequenced, and phylogenetic form on SQUA genes in angiosperms was analyzed. Relative rate and adaptive evolution after SQUA gene duplication in recent common ancestor of monocots and eudicots were analyzed using the methods of relative rate test, statistic on synonymous and non-synonymous coden substitution sites and likelihood rate test. The results show that both of relative rate and synonymous and non-synonymous coden substitution in eudicot clade are significantly higher than those in monocot clade, and the value of dN/ds uncovered possible positive selective pressure in eudicot clade.  相似文献   

14.
The excision repair cross-complementing group 2(ERCC2)gene encodes a DNA repair protein,which is absolutely necessary in nucleotide excision repair.A polymorphism in codon 751 that induces a Lys→Gln substitution has been suggested to reduce the DNA repair capacity.Therefore,we conducted a matched case-control study to investigate the role of ERCC2 Lys751Gln polymor- phism in the development of lung cancer in the Chinese population.The genotype of ERCC2 gene was analyzed by di-allele-specific-amplifi- cation with artificially modified primers(diASA-AMP)in 200 original lung cancer cases and 200 controls.The results showed that carriers of Lys/Gln and Gln/Gln genotypes had a 3.32-fold higher risk of lung cancer compared with carriers of Lys/Lys genotype.Furthermore, the mutant genotypa of 751Gln allele was found to be associated with an increased risk in both lung squamous cell carcinoma and lung ade- nocarcinoma.However,no significant interaction between 751Gln variants and smoking was observed after stratifying according to the smoking status in this study.The results suggest that the Lys751Gln polymorphism in ERCC2 gene is a potential biomarker for suscepti- bility of lung cancer in the Chinese population.  相似文献   

15.
The excision repair cross-complementing group 2 (ERCC2) gene encodes a DNA repair protein, which is absolutely necessary in nucleotide excision repair. A polymorphism in codon 751 that induces a Lys→Gln substitution has been suggested to reduce the DNA repair capacity. Therefore, we conducted a matched case-control study to investigate the role of ERCC2 Lys751Gln polymorphism in the development of lung cancer in the Chinese population. The genotype of ERCC2 gene was analyzed by di-allele-specific-amplification with artificially modified primers (diASA-AMP) in 200 original lung cancer cases and 200 controls. The results showed that carriers of Lys/Gln and Gln/Gln genotypes had a 3.32-fold higher risk of lung cancer compared with carriers of Lys/Lys genotype. Furthermore, the mutant genotype of 751Gln allele was found to be associated with an increased risk in both lung squamous cell carcinoma and lung adenocarcinoma. However, no significant interaction between 751Gln variants and smoking was observed after stratifying according to the smoking status in this study. The results suggest that the Lys751Gln polymorphism in ERCC2 gene is a potential biomarker for susceptibility of lung cancer in the Chinese population.  相似文献   

16.
Software system can be classified into many function modules from the perspective of user. Unified modeling language( UML) class diagram of each function module was extracted,and design characteristic metrics which influenced software maintainability were selected based on UML class diagram.Choosing metrics of UML class diagram as predictors,and mean maintenance time of function module was regarded as software maintainability parameter. Software maintainability models were built by using back propagation( BP) neural network and radial basis function( RBF) neural network, respectively and were simulated by MATLAB. In order to evaluate the performance of models,the training results were analyzed and compared with leaveone-out cross-validation and model performance evaluation criterion. The result indicated that RBF arithmetic was superior to BP arithmetic in predicting software maintainability.  相似文献   

17.
Increasing complexity of distributed hydrological model (DHM) has lowered the efficiency of convergence.In this study,global sensitivity analysis (SA) was introduced by combining multiobjective (MO) optimization for DHM calibration.Latin Hypercube-once at a time (LH-OAT) was adopted in global parameter SA to obtain relative sensitivity of model parameter,which can be categorized into different sensitivity levels.Two comparative study cases were conducted to present the efficiency and feasibility by combining SA with MO(SA-MO).WetSpa model with non-dominated sorting genetic algorithm-Ⅱ (NSGA-Ⅱ) algorithm and EasyDHM model with multi-objective sequential complex evolutionary metropolis-uncertainty analysis (MOSCEM-UA)algorithm were adopted to demonstrate the general feasibility of combining SA in optimization.Results showed that the LH-OAT was globally effective in selecting high sensitivity parameters.It proves that using parameter from high sensitivity groups results in higher convergence efficiency.Study case Ⅰ showed a better Pareto front distribution and convergence compared with model calibration without SA.Study case Ⅱ indicated a more efficient convergence of parameters in sequential evolution of MOSCEM-UA under the same iteration.It indicates that SA-MO is feasible and efficient for high dimensional DHM calibration.  相似文献   

18.
The thermoplasticity of duplex stainless steel 2205 (DSS2205) is better than that of lean duplex steel 2101 (LDX2101), which undergoes severe cracking during hot rolling. The microstructure, microhardness, phase ratio, and recrystallization dependence of the deformation compatibility of LDX2101 and DSS2205 were investigated using optical microscopy (OM), electron backscatter diffraction (EBSD), Thermo-Calc software, and transmission electron microscopy (TEM). The results showed that the phase-ratio transformations of LDX2101 and DSS2205 were almost equal under the condition of increasing solution temperature. Thus, the phase transformation was not the main cause for the hot plasticity difference of these two steels. The grain size of LDX2101 was substantially greater than that of DSS2205, and the microhardness difference of LDX2101 was larger than that of DSS2205. This difference hinders the transfer of strain from ferrite to austenite. In the rolling process, the ferrite grains of LDX2101 underwent continuous softening and were substantially refined. However, although little recrystallization occurred at the boundaries of austenite, serious deformation accumulated in the interior of austenite, leading to a substantial increase in hardness. The main cause of crack formation is the microhardness difference between ferrite and austenite.  相似文献   

19.
The influence of particle migration induced by groundwater source heat pump( GWSHP) operation on aquifer parameters was theoretically analyzed. Then the sensitivity analysis of different influencing factors,which influenced aquifer parameters with GWSHP operation,was evaluated by using grey relational analysis method through a case study. The present study indicated that the erosion parameter, hydraulic conductivity and initial concentration were critical influencing factors which affected the aquifer parameters and the suitability of GWSHP. It also indicated that the discharge of single well should be controlled and the diameter of single well should be selected appropriately in order to decrease particle migration.  相似文献   

20.
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