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1.
Chinese Journal of Nephrology ; (12): 974-979, 2021.
Article in Chinese | WPRIM | ID: wpr-911917

ABSTRACT

Objective:To investigate the relationship between serum C3 and progression of renal function in IgA nephropathy.Methods:A single-center retrospective cohort study was conducted in patients with IgA nephropathy confirmed by renal biopsy who were admitted to the Second People's Hospital of Shenzhen from January 2011 to June 2020 and the patients were followed up until January 2021. Patients with secondary IgA nephropathy, baseline estimated glomerular filtration rate (eGFR)<30 ml·min -1·(1.73 m 2) -1, lack of baseline serum C3 or creatinine, and follow-up time<6 months were excluded. The clinical data, laboratory examination and renal pathology were collected. The threshold effect analysis was used to obtain the cut-off point, and inflection point and 95% confidence interval were obtained using bootstrapping resampling technique. According to the cut-off point, the patients were divided into serum C3<0.97 g/L group and C3≥0.97 g/L group. The baseline data between the two groups were compared. Cox regression model was used to analyze the correlation between serum C3 level and renal function progression. Results:A total of 414 patients were enrolled in this study, with 145 males (35.0%), and age of (35.15±9.18) years old. The baseline eGFR was 77.80(46.67, 106.10) ml·min -1·(1.73 m 2) -1, and the serum C3 was (1.04 ± 0.19) g/L. There were 153 patients with serum C3<0.97 g/L and 261 patients with serum C3≥0.97 g/L. Compared to patients with serum C3≥0.97 g/L, those patients with serum C3<0.97 g/L were younger and had higher proportion of females, higher levels of hemoglobin and eGFR, and lower levels of mean arterial pressure, total cholesterol, triglyceride, serum uric acid, serum creatinine, 24 h urinary protein, IgA and C4 (all P<0.05). The relationship between serum C3 and progression of renal function was found to be U-shaped by smooth curve fitting. After adjustment for confounding factors such as age, sex, mean arterial pressure, serum uric acid, 24 h urinary protein, and renal pathology (MESTC), the results of the threshold effect and multivariate Cox regression showed, for patients with C3<0.97 g/L, the risk of renal function progression decreased by 40% for every 0.1 g/L increase of C3 ( HR=0.60, 95% CI 0.39-0.94, P=0.024), but for patients with C3≥0.97 g/L, every 0.1 g/L increase in serum C3 increased the risk of renal function progression by 27%( HR=1.27, 95% CI 1.03-1.57, P=0.027). The inflection point was 0.97(95% CI 0.92-1.01) g/L. Conclusions:Serum C3 is nonlinear correlated with the progression of renal function in patients with IgA nephropathy. Serum C3 level maintaining at 0.92-1.01 g/L is associated with better renal prognosis.

2.
Acta Pharmaceutica Sinica ; (12): 3547-3554, 2021.
Article in Chinese | WPRIM | ID: wpr-906827

ABSTRACT

According to the commonly used tablet compressibility, compactability and tabletability equation, the influence of pressure range on the fitting results and parameters of different compression equations was studied, and the optimal pressure range of different equations was determined. Plastic material microcrystalline cellulose (MCC) PH102, brittle material spray dried lactose and Chinese medicine Sanqi were used as experimental objects, the compression curves of tablets were obtained by the combination of dies with different diameters. For Heckel equation, the shape of Heckel section of different materials is not uniform, and the specified linear fitting range cannot be obtained, therefore, different distances between fitting pressure starting point and starting point were set to observe the influence of pressure range on R2 of Heckel equation. The Kawakita equation, Gurnham equation, Ryshkewitch-Duckworth (R-D) equation and Power equation are fitted in three different pressure ranges of 15-200, 15-300 and 15-400 MPa, respectively. In order to find the best linear region of Heckel equation, the 3D scatter diagram of "starting point of pressure, pressure range and R2" is drawn. The best linear pressure ranges of Heckel curves of MCC, lactose and Sanqi were 20-170, 20-220 and 10-90 MPa, respectively. It is proved that the 3D scatter diagram is an effective method to find the linear range of Heckel equation. The change of pressure range has little influence on the curve fitting effect and compression parameters of Kawakita equation, Gurnham equation and Ryshkewitch-Duckworth equation. The low pressure range of 15-200 MPa can meet the fitting requirements of Kawakita equation, Gurnham equation, R-D equation and Power equation for different materials. Therefore, only by optimizing the pressure range, can the good fitting effect be ensured and the obtained compression parameters be more reliable and interpretable.

3.
Chinese Journal of Medical Instrumentation ; (6): 259-262, 2019.
Article in Chinese | WPRIM | ID: wpr-772512

ABSTRACT

OBJECTIVE@#To design a rapid scoliosis detection system for general survey.@*METHODS@#The camera was used to take the upright image of human back, and then the region of interest was extracted. After image preprocessing, the feature points of human back spine were extracted. The feature points were fitted into the spine contour curve. Finally, the Cobb angle of scoliosis was calculated according to the contour curve, and the scoliosis degree was judged.@*RESULTS@#The outline curve of the spine can be obtained by this method, and the Cobb angle of scoliosis can be calculated. It can detect scoliosis quickly, effectively and accurately.@*CONCLUSIONS@#Compared with the traditional methods, the digital image processing method can achieve rapid and non-destructive detection of scoliosis, save a lot of manpower and material resources, and is of great significance to the national survey of adolescent scoliosis.


Subject(s)
Adolescent , Humans , Image Processing, Computer-Assisted , Reproducibility of Results , Scoliosis , Spine , Diagnostic Imaging , Surveys and Questionnaires
4.
Journal of Biomedical Engineering ; (6): 414-420, 2019.
Article in Chinese | WPRIM | ID: wpr-774190

ABSTRACT

The convective polymerase chain reaction (CCPCR) uses the principle of thermal convection to allow the reagent to flow in the test tube and achieve the purpose of amplification by the temperature difference between the upper and lower portions of the test tube. In order to detect the amplification effect in real time, we added a fluorophore to the reagent system to reflect the amplification in real time through the intensity of fluorescence. The experimental results show that the fluorescence curve conforms to the S-type trend of the amplification curve, but there is a certain jitter condition due to the instability of the thermal convection, which is not conducive to the calculation of the cycle threshold (CT value). In order to solve this problem, this paper uses the dynamic method, using the double S-type function model to fit the curve, so that the fluorescence curve is smooth and the initial concentration of the nucleic acid can be deduced better to achieve the quantitative purpose based on the curve. At the same time, the PSO+ algorithm is used to solve the double s-type function parameters, that is, particle swarm optimization (PSO) algorithm combined with Levenberg-Marquardt, Newton-CG and other algorithms for curve fitting. The proposed method effectively overcoms PSO randomness and the shortcoming of traditional algorithms such as Levenberg-Marquardt and Newton-CG which are easy to fall into the local optimal solution. The of the data fitting result can reach 0.999 8. This study is of guiding significance for the future quantitative detection of real-time fluorescent heat convection amplification.


Subject(s)
Algorithms , Fluorescence , Fluorescent Dyes , Polymerase Chain Reaction
5.
Indian Heart J ; 2018 Jul; 70(4): 511-518
Article | IMSEAR | ID: sea-191605

ABSTRACT

Objective To develop a mobile app called “TMT Predict” to predict the results of Treadmill Test (TMT), using data mining techniques applied to a clinical dataset using minimal clinical attributes. To prospectively test the results of the app in realtime to TMT and correlate with coronary angiogram results. Methods In this study, instead of statistics, data mining approach has been utilized for the prediction of the results of TMT by analyzing the clinical records of 1000 cardiac patients. This research employed the Decision Tree algorithm, a new modified version of K-Nearest Neighbor (KNN) algorithm, K-Sorting and Searching (KSS). Furthermore, curve fitting mathematical technique was used to improve the Accuracy. The system used six clinical attributes such as age, gender, body mass index (BMI), dyslipidemia, diabetes mellitus and systemic hypertension. An Android app called “TMT Predict” was developed, wherein all three inputs were combined and analyzed. The final result is based on the dominating values of the three results. The app was further tested prospectively in 300 patients to predict the results of TMT and correlate with Coronary angiography. Results The accuracy of predicting the result of a TMT using data mining algorithms, Decision Tree and K-Sorting & Searching (KSS) were 73% and 78%, respectively. The mathematical method curve fitting predicted with 82% accuracy. The accuracy of the mobile app “TMT Predict”, improved to 84%. Age-wise analysis of the results show that the accuracy of the app dips when the age is more than 60 years indicating that there may be other factors like retirement stress that may have to be included. This gives scope for future research also. In the prospective study, the positive and negative predictive values of the app for the results of TMT and coronary angiogram were found to be 40% and 83% for TMT and 52% and 80% for coronary angiogram. The negative predictive value of the app was high, indicating that it is a good screening tool to rule out coronary artery heart disease (CAHD). Conclusion “TMT Predict” is a simple user-friendly android app, which uses six simple clinical attributes to predict the results of TMT. The app has a high negative predictive value indicating that it is a useful tool to rule out CAHD. The “TMT Predict” could be a future digital replacement for the manual TMT as an initial screening tool to rule out CAHD.

6.
Chinese Journal of Medical Aesthetics and Cosmetology ; (6): 188-191, 2018.
Article in Chinese | WPRIM | ID: wpr-712373

ABSTRACT

Objective To study the variation of the dental and basal arch forms before and after orthodontic treatment of patients with skeletal class Ⅱ malocclusion by tooth extraction.Methods The mandibular dental casts of 25 skeletal class Ⅱ patients were laser scanned before and after treatment.The facial axis (FA) points,which were used to represent the dental arch,and the WALA point,which were used to represent the basal bone,were identified for each tooth from the right first molar to the left first molar.We constructed the curve with points of projection of the FA and WALA point on the reference plane,and compared the curve of dental arch and basal bone before and after treatment.Results The width of anterior middle and posterior of the basal arch increased (0.835± 1.259) mm,(1.700±1.280) mm and (2.170±1.227) mm,respectively.While the dental arch had a wider width (1.110±1.566) mm in posterior segment but a narrower one in anterior (3.345±2.907) mm.Conclusions The width of middle and posterior of basal bone represented by WALA ridge becomes wider after orthodontic treatment with tooth extraction in patients with skeletal class Ⅱ malocclusion,while the dental arch turns to a new form,which is more coordinated to the basal bone.

7.
Chinese Journal of Medical Instrumentation ; (6): 79-83, 2018.
Article in Chinese | WPRIM | ID: wpr-774504

ABSTRACT

This paper realized an electromagnetic tracking system based on electrically-controlled rotating magnetic field. A tracking system using the digital signal processor (DSP) as the control processing device was developed, including a controllable constant current source module, a magnetic field source module, a three-axis magnetic sensor and ADC interface circuit. The experimental results verified that each time the system could be stable positioning, average error of position was 0.282 cm, the average error of orientation was 0.696o, the positioning time was 1.572 s. Through calibration and further improvement of the hardware circuit, the performance of the system is expected to further improve.


Subject(s)
Calibration , Electromagnetic Phenomena , Equipment Design , Magnetic Fields
8.
World Science and Technology-Modernization of Traditional Chinese Medicine ; (12): 1711-1714, 2015.
Article in Chinese | WPRIM | ID: wpr-478651

ABSTRACT

The research on regulation rules of traditional Chinese medicine (TCM) syndrome was the core of TCM syndrome information. It was thought that the constitution identification which provided the technology for evaluating health status was one of the bases in drawing the curve of conditional standard of syndrome. It was fitted and analyzed by the curve of conditional evolution of syndrome through establishing the curve of conditional standard of TCM constitution theory. It was the key technology of realizing the dynamical evaluation of TCM clinical effect.

9.
Nutrition Research and Practice ; : 368-376, 2014.
Article in English | WPRIM | ID: wpr-142640

ABSTRACT

BACKGROUND/OBJECTIVES: The objectives of this study were to investigate the effects of lycopene on the migration, adhesion, tube formation capacity, and p38 mitogen-activated protein kinase (p38 MAPK) activity of endothelial progenitor cells (EPCs) cultivated with high glucose (HG) and as well as explore the mechanism behind the protective effects of lycopene on peripheral blood EPCs. MATERIALS/METHODS: Mononuclear cells were isolated from human peripheral blood by Ficoll density gradient centrifugation. EPCs were identified after induction of cellular differentiation. Third generation EPCs were incubated with HG (33 mmol/L) or 10, 30, and 50 microg/mL of lycopene plus HG. MTT assay and flow cytometry were performed to assess proliferation and apoptosis of EPCs. EPC migration was assessed by MTT assay with a modified boyden chamber. Adhesion assay was performed by replating EPCs on fibronectin-coated dishes, after which adherent cells were counted. In vitro vasculogenesis activity was assayed by Madrigal network formation assay. Western blotting was performed to analyze protein expression of both phosphorylated and non-phosphorylated p38 MAPK. RESULTS: The proliferation, migration, adhesion, and in vitro vasculogenesis capacity of EPCs treated with 10, 30, and 50 microg/mL of lycopene plus HG were all significantly higher comapred to the HG group (P < 0.05). Rates of apoptosis were also significantly lower than that of the HG group. Moreover, lycopene blocked phosphorylation of p38 MAPK in EPCs (P < 0.05). To confirm the causal relationship between MAPK inhibition and the protective effects of lycopene against HG-induced cellular injury, we treated cells with SB203580, a phosphorylation inhibitor. The inhibitor significantly inhibited HG-induced EPC injury. CONCLUSIONS: Lycopene promotes proliferation, migration, adhesion, and in vitro vasculogenesis capacity as well as reduces apoptosis of EPCs. Further, the underlying molecular mechanism of the protective effects of lycopene against HG-induced EPC injury may involve the p38 MAPK signal transduction pathway. Specifically, lycopene was shown to inhibit HG-induced EPC injury by inhibiting p38 MAPKs.


Subject(s)
Humans , Apoptosis , Blotting, Western , Centrifugation, Density Gradient , Ficoll , Flow Cytometry , Glucose , p38 Mitogen-Activated Protein Kinases , Phosphorylation , Protein Kinases , Signal Transduction , Stem Cells
10.
Nutrition Research and Practice ; : 368-376, 2014.
Article in English | WPRIM | ID: wpr-142637

ABSTRACT

BACKGROUND/OBJECTIVES: The objectives of this study were to investigate the effects of lycopene on the migration, adhesion, tube formation capacity, and p38 mitogen-activated protein kinase (p38 MAPK) activity of endothelial progenitor cells (EPCs) cultivated with high glucose (HG) and as well as explore the mechanism behind the protective effects of lycopene on peripheral blood EPCs. MATERIALS/METHODS: Mononuclear cells were isolated from human peripheral blood by Ficoll density gradient centrifugation. EPCs were identified after induction of cellular differentiation. Third generation EPCs were incubated with HG (33 mmol/L) or 10, 30, and 50 microg/mL of lycopene plus HG. MTT assay and flow cytometry were performed to assess proliferation and apoptosis of EPCs. EPC migration was assessed by MTT assay with a modified boyden chamber. Adhesion assay was performed by replating EPCs on fibronectin-coated dishes, after which adherent cells were counted. In vitro vasculogenesis activity was assayed by Madrigal network formation assay. Western blotting was performed to analyze protein expression of both phosphorylated and non-phosphorylated p38 MAPK. RESULTS: The proliferation, migration, adhesion, and in vitro vasculogenesis capacity of EPCs treated with 10, 30, and 50 microg/mL of lycopene plus HG were all significantly higher comapred to the HG group (P < 0.05). Rates of apoptosis were also significantly lower than that of the HG group. Moreover, lycopene blocked phosphorylation of p38 MAPK in EPCs (P < 0.05). To confirm the causal relationship between MAPK inhibition and the protective effects of lycopene against HG-induced cellular injury, we treated cells with SB203580, a phosphorylation inhibitor. The inhibitor significantly inhibited HG-induced EPC injury. CONCLUSIONS: Lycopene promotes proliferation, migration, adhesion, and in vitro vasculogenesis capacity as well as reduces apoptosis of EPCs. Further, the underlying molecular mechanism of the protective effects of lycopene against HG-induced EPC injury may involve the p38 MAPK signal transduction pathway. Specifically, lycopene was shown to inhibit HG-induced EPC injury by inhibiting p38 MAPKs.


Subject(s)
Humans , Apoptosis , Blotting, Western , Centrifugation, Density Gradient , Ficoll , Flow Cytometry , Glucose , p38 Mitogen-Activated Protein Kinases , Phosphorylation , Protein Kinases , Signal Transduction , Stem Cells
11.
Chinese Journal of Epidemiology ; (12): 711-713, 2013.
Article in Chinese | WPRIM | ID: wpr-318315

ABSTRACT

Objective To study the relationship of per-capita tobacco consumption and lung cancer mortality in Henan province,and to provide evidence for policy development on tobacco control and reduction of lung cancer mortality.Methods Data regarding lung cancer mortality and per-capita tobacco consumption among household residents from 1992 to 2011,was collected from published almanacs in Henan and Henan Tumor Institutes.Trend Method was used to analyze the development of lung cancer in Henan province and the trend of per-capita tobacco consumption of residents in the household.‘Spearman rank correlation' was used to analyze the correlation between per-capita tobacco consumption of residents in the household from 1992 to 2001 and the lung cancer mortality rates from 2002 to 2011,with the lag time unite as 10 years in this study.Cure Estimation was used to fit the model regarding the relationship between per-capita tobacco consumption of residents in the household and lung cancer.Results Lung cancer mortality among those permanent residents in Henan province increased from 14.75/100 000 in 1992 to 27.00/100 000 in 2011,with an increase of 83.05%.Both the trend of per-capita tobacco consumption among the permanent residents and the lung cancer mortality were uprising,with the tobacco consumption showing a lag effect to the lung cancer mortality.Correlation coefficient between the per-capita tobacco consumption of residents in the household from 1992 to 2001 and the lung cancer mortality from 2002 to 2011 was rs=0.770,P=0.009<0.05,with statistically significant difference.Along with the uprising trend of lung cancer mortality,the per-capita tobacco consumption of residents in the household was also parallelly rising with the equation of relevance betweenper-capita tobacco consumption of residents in the household in Henna province and lung cancer as y =2.60 x0.46 (F=576.483) and the R2 was 0.667.Conclusion Per-capita tobacco consumption of residents in the household in Henan province appeared a factor that influencing the lung cancer mortality and an association between the per-capita tobacco consumption of residents in the household and lung cancer was noticed.Tobacco consumption had a lag trend to the mortality of lung cancer.

12.
Chinese Journal of Digestive Endoscopy ; (12): 328-331, 2013.
Article in Chinese | WPRIM | ID: wpr-434911

ABSTRACT

Objective Study the drug resistance trend of Helicobacter pylori (H.pylori) based on polynomial regression equation to provide reference for clinical medication.Methods A total of 3496 clinical isolates of H.pylori collected from 2007 to 2012 were used for drug sensitivity test of six common-used drugs to evaluate the resistance rate of each drug.Correlation analysis were performed on each of the two drugs.Constructed log curve,exponential curve,inverted exponential curve,polynomial curve and sigmoid curve for each kind of drug resistance rate and did regression analysis for each drug resistance rate.Results According to the results of drug sensitivity test from 2007 to 2012,amoxicillin,furazolidone and gentamicin had strong antibacterial activity to H.pylori and got a lower drug resistance rate.The resistance rate of levofloxacin and clarithromycin were increasing year by year and the resistance of metronidazole had been maintained at a high level.The predictive drug resistance rate of clarithromycin,metronidazole,levofloxacin,amoxycillin,gentamicin and furaxone in 2013 were 21.49%,95.47%,20.70%,0.10%,0.09% and 0.10%,respectively.The results were consistent with those of H.pylori infection rate in Southeast China performed by Jianzhong Zhang.Conclusion A certain quantitative relationship exists between the time and the helicobacter resistance rate.The established model can be used to predict the future trend of H.pylori resistance rate.It can be used to guide clinical rotation,the restriction of the use of antibiotics,and to reduce the generation of antibiotic resistant bacteria.

13.
Journal of Huazhong University of Science and Technology (Medical Sciences) ; (6): 119-123, 2012.
Article in Chinese | WPRIM | ID: wpr-248550

ABSTRACT

The accuracy and repeatability of computer aided cervical vertebra landmarking (CACVL) were investigated in cephalogram.120 adolescents (60 boys,60 girls) aged from 9.1 to 17.2 years old were randomly selected.Twenty-seven landmarks from the second to fifth cervical vertebrae on the lateral cephalogram.were identified.In this study,the system of CACVL was developed and used to identify and calculate the landmarks by fast marching method and parabolic curve fitting.The accuracy and repeatability in CACVL group were compared with those in two manual landmarking groups [orthodontic experts (OE) group and orthodontic novices (ON) group].The results showed that,as for the accu racy,there was no significant difference between CACVL group and OE group no matter in x-axis or y-axis (P>0.05),but there was significant difference between CACVL group and ON group,as well as OE group and ON group in both axes (P<0.05).As for the repeatability,CACVL group was more reliable than OE group and ON group in both axes.It is concluded that CACVL has the same or higher accuracy,better repeatability and less workload than manual landmarking methods.It's reliable for cervical parameters identification on the lateral cephalogram and cervical vertebral maturation prediction in orthodontic practice and research.

14.
Chinese Journal of Digestive Endoscopy ; (12): 5-8, 2011.
Article in Chinese | WPRIM | ID: wpr-382662

ABSTRACT

Objective To investigate the method of locating intestinal lesions by scatter diagram which simulating the movement of capsule endoscopy in small intestine and its significance. Methods A total of 30 consecutive patients with lesions in small intestine which was diagnosed by wireless capsule endoscopy (WCE) and confirmed by following surgery were enrolled in the study as group A. The time index was defined as the ratio of the transition time from the duodenojejunal flexure to the lesion to that to the ileocaecal valve. For each case in group A, the time index was marked on a horizontal axis with the distance between duodenojejunal flexure and the lesion on a vertical axis. The best curve was obtained to simulate the intestinal movement, and 30 other patients selected by the same criteria were used as group B to testify the accuracy of the curve. Results Parabola and quadratic equation were obtained from group A to simulate the intestinal peristalsis. Calculation of errors in group B showed a minimal error of 0. 79 cm, a maximal error of 41.49 cm and a mean error of ( 19. 64± 13. 98 ) cm. Patients with errors less than 20 cm accounted for 50%(15/30), those with errors less than 30 cm were 67% (20/30), and those with errors less than 50 cm amounted to 100% (30/30). Conclusion Locating the lesion in small intestine by transition time of WCE is of high accuracy and is able to facilitating the diagnosis yield of WCE.

15.
Rev. bras. colo-proctol ; 29(1): 51-56, jan.-mar. 2009. ilus, graf, tab
Article in Portuguese | LILACS | ID: lil-518064

ABSTRACT

OBJETIVO: avaliar a dispersão de curvas Força x Elongação (FE) representativas do comportamento mecânico de alça cólica íntegra de ratos. MATERIAIS E MÉTODOS: dez segmentos de cólon descendente de ratos machos Wistar foram submetidos ao teste biomecânico Energia Total de Ruptura. Cada curva gerada por esse ensaio foi ajustada ao modelo de Boltzmann, o qual correlaciona os valores de força e elongação por meio da combinação dos parâmetros A1, A2, x0 e d x. Nesse contexto, para cada parâmetro, foram calculadas as médias, os desvios padrão e correlações. Após, determinou-se a dispersão resultante da força em todo processo de deformação através de uma análise que considera as correlações entre as grandezas, com base na lei de propagação das incertezas. Para determinar um intervalo no qual estarão contidos 95% dos valores de força, a dispersão resultante foi multiplicada por um fator de abrangência considerando-se uma distribuição normal. RESULTADOS: os valores da média, do desvio padrão e das correlações foram determinados. A dispersão resultante dos valores de força foi expandida, delineando-se limites dentro dos quais estarão contidas as curvas FE para um intervalo de confiança de 95%. CONCLUSÃO: essa metodologia poderá auxiliar na avaliação de variáveis que interfiram no comportamento mecânico intestinal.


PURPOSE: to evaluate the dispersion of Force x Elongation curves (FE) that represents the mechanical behavior of rat's colon. MATERIALS AND METHODS: ten descending colon segments were submitted to the Total Energy of Rupture Test. Each curve generated by this test was fitted to Boltzmann model that correlates the values of force and elongation through the combination of the parameters A1, A2, x0 and d x. Then, for each parameter were calculated the mean, standard deviation and their correlations. Later, the resultant dispersion was determinated in the whole deformation process by an analysis that considers the correlations between the greatnesses based on the propagation of uncertainties law. The resultant dispersion was multiplied by a coverage factor, considering a normal distribution, to determinate an interval in which 95% of force values will be present. RESULTS: the mean, standard deviation and correlation were determined. The resultant dispersion of force values was expanded drawing limits inside which FE curves will be for a confidence interval of 95%. CONCLUSION: this methodology will be possibly used to evaluate variables that act on the intestinal mechanical behavior.


Subject(s)
Animals , Rats , Biomechanical Phenomena , Colon , Experimental Development , General Surgery , Intestinal Fistula , Models, Theoretical
16.
Journal of the Korean Society of Magnetic Resonance in Medicine ; : 103-109, 2007.
Article in Korean | WPRIM | ID: wpr-227811

ABSTRACT

To develop an advanced non-linear curve fitting (NLCF) algorithm for performing dynamic susceptibility contrast study of the brain. The first pass effects give rise to spuriously high estimates of Ktrans for the voxels that represent the large vascular components. An explicit threshold value was used to reject voxels. The blood perfusion and volume estimation were accurately evaluated in the T2*-weighted dynamic contrast enhanced (DCE)-MR images. From each of the recalculated parameters, a perfusion weighted image was outlined by using the modified non-linear curve fitting algorithm. The present study demonstrated an improvement of an estimation of the kinetic parameters from the DCE T2*-weighted magnetic resonance imaging data with using contrast agents.


Subject(s)
Humans , Brain , Contrast Media , Gadolinium DTPA , Magnetic Resonance Imaging , Perfusion
17.
International Journal of Laboratory Medicine ; (12)2006.
Article in Chinese | WPRIM | ID: wpr-528050

ABSTRACT

Objective To discuss the clinical application of polynomial curves fitting.Methods Based on the experiments of TBIL, ALT, DBIL and Cr,the linear experimental data were polynomial fitted.Results The optimal polynomial of TBIL is y=-3.886+7.544x , and the evaluation is linear 1; The optimal polynomial of ALT is y=5.293+25.897x-0.043 x~2, and the evaluation is linear 2;The optimal polynomial of DBIL is y=-2.950+1.688x+0.011x~2, and it′s non-linear; The optimum polynomial of Cr is y=11.654+14.512x-0.010 x~2, and the evaluation is inexactitude.Conclusion The polynomial fitting curve is the perfect linear evaluation method. It guarantees both the accuracy and reliability of the experimental results, and is more suitable to clinic.

18.
China Pharmacy ; (12)2005.
Article in Chinese | WPRIM | ID: wpr-530776

ABSTRACT

OBJECTIVE:To investigate the drug quality in rural area during the period of the national rural "two networks" construction.METHODS:A questionnaire investigation on the rate of qualified during 5 years was conducted in which the data of 26 provinces(or cities)which were valid were given a curve fitting analysis.RESULTS:The rate of qualified of chemical drug showed an increasing tendency year by year,so did the Chinese traditional medicine.And the latter's development trend was better than the former.CONCLUSIONS:The eligible proportion of drugs showed an uptrend year by year,and the "two networks" construction in rural areas remarkably enhanced the drug quality in rural area.

19.
Korean Journal of Nuclear Medicine ; : 257-262, 2005.
Article in Korean | WPRIM | ID: wpr-115915

ABSTRACT

PURPOSE: Gastric emptying scan (GES) is usually acquired up to 2 hours. Our study investigated whether a fraction of meal-retention in the stomach at 120 minutes (FR120) was predicted from the data measured for 90 minutes by using non-linear curve fitting. We aimed at saving the delayed imaging by utilizing mathematical models. MATERIALS AND METHODS: Ninety-six patients underwent GES immediately after taking a boiled egg with 74 MBq (2 mCi) Tc-99m DTPA. The patients were divided into Group I (T1/2 < or=90 min) and Group II (90 min< T1/2< or=120 min). Group I (n=51) had 21 men and 30 women, and Group II (n=45) 15 men and 30 women. There was no significant difference in age and sex between the two groups. Simple exponential, power exponential, and modified power exponential curves were acquired from the measured fraction of meal-retention at each time (0, 15, 30, 45, 60, 75, and 90 min) by non-linear curve fitting (MATLAB (R) 5.3) and another simple exponential fitting was performed on the fractions at late times (60, 75, and 90 min). A predicted FR120 was calculated from the acquired functional formulas. A correlation coefficient between the measured FR120 and the predicted FR120 was computed (MedCalc (R) 6.0). RESULTS: Correlation coefficients (r) between the measured FR120 and the predicted FR120 of each mathematical functions were as follows: simple exponential function (Group I: 0.8858, Group II: 0.5982, p< 0.0001), power exponential function (Group I: 0.8755, Group II: 0.6008, p< 0.0001), modified power exponential function (Group I: 0.8892, Group II: 0.5882, p< 0.0001), and simple exponential function at the late times (Group I: 0.9085, Group II: 0.6832, p< 0.0001). In all the fitting models, the predicted FR120 were significantly correlated with the measured FR120 in Group I but not in Group II. There was no statistically significant difference in correlation among the 4 mathematical models. CONCLUSION: In the cases with T1/2 < or=90 min, the predicted FR120 is significantly correlated with the measured FR120. Therefore, FR120 can be predicted from the data measured for 90 minutes by using non-linear curve fitting, saving the delayed imaging after 90 minutes when T1/2 < or=90 min is ascertained.


Subject(s)
Female , Humans , Male , Gastric Emptying , Models, Theoretical , Ovum , Pentetic Acid , Radionuclide Imaging , Stomach
20.
Journal of the Korean Society of Magnetic Resonance in Medicine ; : 36-42, 2005.
Article in Korean | WPRIM | ID: wpr-141559

ABSTRACT

PURPOSE: To develop a novel approach to calculate the sensitivity profiles of the phased array coil for use in non-uniform intensity correction. MATERIALS AND METHODS: The proposed intensity correction method estimates the sensitivity profile of the coil to extract intensity variations that represent the scanned image. The sensitivity profile is estimated by fitting a non-linear curve to various angles of projections through the imaged object in order to eliminate the high-frequency image content. Filtered back projection is then used to compute the estimates of the sensitivity profile of each coil. The method was applied both to phantom and brain images from 8-channel phased-array coil and 4-channel phased-array coil, respectively. RESULTS: Intensity-corrected images from the proposed method have more uniform intensity than those from the commonly used `sum-of-squares' approach. By using the proposed correction method, the intensity variation was reduced to 6.1% from 13.1%, acquired from the `sum-of-squares'. CONCLUSION: The proposed method is more effective at correcting the intensity non-uniformity of the phased-array surface-coil images than the conventional`sum-of-squares' method.


Subject(s)
Brain
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