Objective To evaluate the sensitivity and specificity of body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) measurements in diagnosing abdominal visceral obesity. Methods BMI, WC, and WHR wer...Objective To evaluate the sensitivity and specificity of body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) measurements in diagnosing abdominal visceral obesity. Methods BMI, WC, and WHR were assessed in 690 Chinese adults (305 men and 385 women) and compared with magnetic resonance imaging (MRI) measurements of abdominal visceral adipose tissue (VA). Receiver operating characteristic (ROC) curves were generated and used to determine the threshold point for each anthropometric parameter. Results 1) MRI showed that 61.7% of overweight/obese individuals (BMI≥25 kg/m2) and 14.2% of normal weight (BMI<25 kg/m2) individuals had abdominal visceral obesity (VA≥100 cm2). 2) VA was positively correlated with each anthropometric variable, of which WC showed the highest correlation (r=0.73-0.77, P<0.001). 3) The best cut-off points for assessing abdominal visceral obesity were as followed: BMI of 26 kg/m2, WC of 90 cm, and WHR of 0.93, with WC being the most sensitive and specific factor. 4) Among subjects with BMI≥28 kg/m2 or WC≥95 cm, 95% of men and 90% of women appeared to have abdominal visceral obesity. Conclusion Measurements of BMI, WC, and WHR can be used in the prediction of abdominal visceral obesity, of which WC was the one with better accuracy.展开更多
BACKGROUND: The various combination of multiphase enhancement multislice spiral CT (MSCT) makes the diagno- sis of a small hepatocellular carcinoma (sHCC) on the back- ground of liver cirrhosis possible. This stu...BACKGROUND: The various combination of multiphase enhancement multislice spiral CT (MSCT) makes the diagno- sis of a small hepatocellular carcinoma (sHCC) on the back- ground of liver cirrhosis possible. This study was to explore whether the combination of MSCT enhancement scan and alpha-fetoprotein (AFP) level ficiency for sHCC. could increase the diagnostic ef- METHODS: This study included 35 sHCC patients and 52 cir- rhotic patients without image evidence of HCC as a control group. The diagnoses were made by three radiologists em- ploying a 5-point rating scale, with postoperative pathologic results as the gold standard. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diag- nostic value of the three MSCT combination modes (arterial phase+portal-venous phase, arterial phase+delayed phase, arterial phase+portal-venous phase+delayed phase) and AFP levels for sHCC on the background of liver cirrhosis. RESULTS: The area under ROC curve (AUC), sensitivity, and specificity of the combination of arterial phase+portal- venous phase+delayed phase were 0.93, 93%, and 82%, respectively. The average AUC of the arterial phase+portal- venous phase+delayed phase combination was significantly greater than that of the arterial phase+portal-venous phase (AUC=0.84, P=0.01) and arterial phase+delayed phase (AUC=0.85, P=0.03). Arterial phase+portal-venous phase had a smaller AUC (0.84) than arterial phase+delayed phase (0.85), but the difference was insignificant (P=0.15). After combining MSCT enhancement scan with AFP, the AUC, sensitivity, and specificity were 0.95, 94%, and 83%, respectively, indicating a greatly increased diagnostic efficiency for sHCC. CONCLUSIONS: The combination of AFP and 3 phases MSCT enhancement scan could increase the diagnostic efficiency for sHCC on the background of liver cirrhosis. The application of ROC curve analysis has provided a new method and reference in HCC diagnosis.展开更多
Objective: To determine the endemic values of cutaneous leishmaniasis in different cities of Fars province, Iran. Methods: Totally, 29 201 cases registered from 2010 to 2015 in Iranian Fars province were selected, and...Objective: To determine the endemic values of cutaneous leishmaniasis in different cities of Fars province, Iran. Methods: Totally, 29 201 cases registered from 2010 to 2015 in Iranian Fars province were selected, and the endemic values of cutaneous leishmaniasis were determined by retrospective clusters derived from spatiotemporal permutation modeling on a time-series design. The accuracy of the values was assessed using receiver operating characteristic(ROC) curve. SPSS version 22, Arc GIS, and ITSM 2002 software tools were used for analysis. Results: Nine statistically significant retrospective clusters(P<0.05) resulted in finding seven significant and accurate endemic values(P<0.1). These valid endemic scores were generalized to the other 18 cities based on 6 different climates in the province. Conclusions: Retrospectively detected clusters with the help of ROC curve analysis could help determine cutaneous leishmaniasis endemic values which are essential for future prediction and prevention policies in the area.展开更多
Aim: To assess that metabolic status of spermatozoa could provide a useful tool for evaluation of semen quality. Methods: The accuracy of the spectrophotometric application of the resazurin reduction assay was asses...Aim: To assess that metabolic status of spermatozoa could provide a useful tool for evaluation of semen quality. Methods: The accuracy of the spectrophotometric application of the resazurin reduction assay was assessed using receiver operating characteristic (ROC) analysis. Results: Areas under ROC curves (AUC) for motile sperm concentration and sperm index (SI) (sperm concentration multiplied by the square root of percentage sperm motility multiplied by the percentage normal sperm morphology) were 0.922. The best discrimination between poor and good semen samples according to the SI was achieved at a cut-off point of A610 = 0.209, where high sensitivity (94.1%) and specificity (91.7%) were calculated. The assay was less accurate when motile sperm concentration was used as the criterion value, yielding sensitivity of 88.2% and specificity of 87.5%, respectively. Likelihood ratios (LR) indicate that absorbances lower than 0.209 were at least 11.3 times as likely to be found in good semen samples than those in poor according to the SI, whereas in the case of motile sperm concentration, the LR was calculated to be 7.06. Conclusion: These results show that the resazurin reduction assay combined with spectrophotometry is an accurate method of assessing the quality of boar semen.展开更多
Objective(s): Laryngeal inflammations lead to voice disorders. Medical conditions such as chronic laryngitis, gastroesophageal reflux, laryngopharyngeal reflux, Reinke edema and/or vocal folds hemorrhage, result in di...Objective(s): Laryngeal inflammations lead to voice disorders. Medical conditions such as chronic laryngitis, gastroesophageal reflux, laryngopharyngeal reflux, Reinke edema and/or vocal folds hemorrhage, result in diverse symptoms including chronic cough, throat cleaning and dysphonia (e.g. hoarseness). In turn, the dysphonic symptoms can be evaluated via subjective and objective procedures. The objective procedures usually include self-perceived questionnaires like the Voice Handicap Index (VHI). Studies reported that VHI can distinguish objectively dysphonic and non-dysphonic populations using the cut-off points of Receiver Operating Characteristic Curves. The purpose of this study was to calculate the cut-off points for individuals exhibiting voice symptoms which had been developed from laryngeal inflammatory diseases in Greece. Methods: One hundred and twelve participants (90 non-dysphonic and 22 dysphonic) filled in the Hellenic Voice Handicap Index (VHI) and the Greek translated version of Voice Evaluation Template (VEF) were administrated. All subjects were evaluated by an Otolaryngologist and a Speech-Language Pathologist. Results: The group with voice disorders exhibited higher VHI scores (in total and in its 3 subdomains) compared to non-dysphonic subgroup. Statistical significant differences were found for all VHI’s total cut-off point of 19.50 (sensitivity: 0.882, 1-specificity: 0.011) and for its three subdomains [functional 6.50 (sensitivity = 0.636, and 1-specificity = 0.022);physical 9.50 (sensitivity = 0.636, and 1-specificity = 0.000);emotional 6.50 (sensitivity = 0.455, and 1-specificity = 0.133)]. Conclusion: The preliminary results showed that VHI could discriminate individuals having voice disorders from laryngeal inflammations. The Voice Handicap Index can be used as a primary health care tool and a self-monitoring procedure in acute and sub-acute phases of the laryngeal inflammation.展开更多
Aim:To assess that metabolic status of spermatozoa could provide a useful tool for evaluation of semen quality. Methods:The accuracy of the spectrophotometric application of the resazurm reduction assay was assessed u...Aim:To assess that metabolic status of spermatozoa could provide a useful tool for evaluation of semen quality. Methods:The accuracy of the spectrophotometric application of the resazurm reduction assay was assessed using receiver operating characteristic(ROC)analysis.Results:Areas under ROC curves(AUC)for motile sperm concen- tration and sperm index(SI)(sperm concentration multiplied by the square root of percentage sperm motility multi- plied by the percentage normal sperm morphology)were 0.922.The best discrimination between poor and good semen samples according to the SI was achieved at a cut-off point of A_(610)=0.209,where high sensitivity(94.1%)and specificity(91.7%)were calculated.The assay was less accurate when motile sperm concentration was used as the criterion value,vielding sensitivity of 88.2% and specificity of 87.5%,respectively,Likelihood ratios(LR)indicate that absorbances lower than 0.209 were at least 11.3 times as likely to be found in good semen samples than those in poor according to the SI,whereas in the case of motile sperm concentration,the LR was calculated to be 7.06.Conclusion: These results show that the resazurin reduction assay combined with spectrophotometry is an accurate method of assessing the quality of boar semen.展开更多
目的:甲状腺功能障碍性视神经病变(dysthyroid optic neuropathy,DON)严重危害甲状腺相关眼病患者视力。本研究观察DON患者的视觉功能改变,并评价DON检测指标的诊断价值。方法:回顾性分析2017年1月至2019年12月在中南大学湘雅医院就诊...目的:甲状腺功能障碍性视神经病变(dysthyroid optic neuropathy,DON)严重危害甲状腺相关眼病患者视力。本研究观察DON患者的视觉功能改变,并评价DON检测指标的诊断价值。方法:回顾性分析2017年1月至2019年12月在中南大学湘雅医院就诊的49例DON患者(98眼)的临床资料。所有患者均行最佳矫正视力(best corrected visual acuity,BCVA)、Humphrey视野、视觉诱发电位(visual evoked potential,VEP)和对比敏感度检测。将98眼分为DON组(45眼)和非DON组(53眼)。采用t检验比较2组患者上述各项检测的相关指标,受试者操作特征(receiver operating characteristic,ROC)曲线分析各指标的敏感度和特异度。结果:DON组的BCVA和视野指数(visual field index,VFI)均显著低于非DON组(均P<0.05),平均缺损(mean deviation,MD)和模式标准偏差(pattern standard deviation,PSD)均显著高于非DON组(均P<0.05)。DON组的低频对比敏感度(low frequency contrast sensitivity,CSL)、中频对比敏感度(medium frequency contrast sensitivity,CSM)、高频对比敏感度(high frequency contrast sensitivity,CSH)均明显低于非DON组(均P<0.05),CSH尤为明显。在15°、30°和60°空间频率时,与非DON组比较,DON组的N135波幅显著降低,N75波、P100波、N135波的潜伏期显著延长(均P<0.05);在15°和30°空间频率时,DON组较非DON组P100波幅明显降低(均P<0.05)。ROC曲线分析结果显示:VFI、CSL、CSM、CSH和15°P100波幅诊断DON的曲线下面积(area under the curve,AUC)分别为0.812、0.841、0.880、0.784和0.791,以CSM的敏感度和特异度最高。结论:DON患者的视觉功能均存在不同程度的受损。VFI、CSL、CSM、CSH和15°P100波幅可能成为早期诊断DON的有效指标。展开更多
Background: To combine dinicopathological characteristics associated with lymph node metastasis for submucosal gastric cancer into a nomogram. Methods: We retrospectively analyzed 262 patients with submucosal gastri...Background: To combine dinicopathological characteristics associated with lymph node metastasis for submucosal gastric cancer into a nomogram. Methods: We retrospectively analyzed 262 patients with submucosal gastric cancer who underwent D2 gastrectomy between 1996 and 2012. The relationship between lymph node metastasis and clinicopathological features was statistically analyzed. With multivariate logistic regression analysis, we made a nomogram to predict the possibility of lymph node metastasis. Receiver operating characteristic (ROC) analysis was also performed to assess the predictive value of the model. Discrimination and calibration were performed using internal validation. Results: A total number of 48 (18.3%) patients with submucosal gastric cancer have pathologically lymph node metastasis. For submucosal gastric carcinoma, lymph node metastasis was associated with age, tumor location, macroscopic type, size, differentiation, histology, the existence of ulcer and lymphovascular invasion in univariate analysis (all P〈0.05). The multivariate logistic old, macroscopic type III or mixed, undifferentiated type, regression analysis identified that age _〈50 years and presence of lymphovascular invasion were independent risk factors of lymph node metastasis in submucosal gastric cancer (all P〈0.05). We constructed a predicting nomogram with all these factors for lymph node metastasis in submucosal gastric cancer with good discrimination [area under the curve (AUC) =0.844]. Internal validation demonstrated a good discrimination power that the actual probability corresponds closely with the predicted probability. Conclusions: We developed a nomogram to predict the rate of lymph node metastasis for submucosal gastric cancer. With good discrimination and internal validation, the nomogram improved individualized predictions for assisting clinicians to make appropriated treatment decision for submucosal gastric cancer patients.展开更多
Along with the development of digital X-ray imaging technology, a new, economical and practicalpaper-based output system gradually emerged. To reduce cost, more and more radiologic institutions began to change from fi...Along with the development of digital X-ray imaging technology, a new, economical and practicalpaper-based output system gradually emerged. To reduce cost, more and more radiologic institutions began to change from film copies to lower-priced paper prints for documenting radiologic findings.Therefore, laser paper printers are frequently used as an alternative to duplicating film though the use of printed images is not yet widespread. The aim of this study was to compare the practical value of high-resolution paper printer with dry film copies for detecting small solitary pulmonary nodules (SPNs).展开更多
Objective: To establish the diagnostic quantitative criteria for fire-heat syndrome (FHS) of Chinese medicine (CM) based on the receiver operating characteristic (ROC) curve and principal component analysis (...Objective: To establish the diagnostic quantitative criteria for fire-heat syndrome (FHS) of Chinese medicine (CM) based on the receiver operating characteristic (ROC) curve and principal component analysis (PCA). Methods: The symptoms and signs of FHS cases and healthy subjects from Guangzhou, Henan and Hunan of China were collected through questionnaire, and the diagnostic quantitative score tables were established for the three regions, respectively, with the method of maximum likelihood analysis. The homogeneity test was then performed on the diagnostic score tables for the three regions with ROC curve, and the diagnostic efficiency of diagnostic score tables for the three regions was compared with the prospective test and retrospective test. The method of PCA was adopted to obtain the analysis matrix for classifying the tapes of FHS. Results: Twenty-seven elements of FHS were confirmed through Chi-square test, and the diagnostic score tables for the three regions were established with the method of maximum likelihood analysis on the basis of the collected case data. According to the ROC curve test, the areas under ROC curve of Guangzhou diagnostic score table assessment with candidates in Guangzhou, Henan and Hunan were 0.998, 0.961 and 0.956, respectively. It showed that the diagnostic efficiency of Guangzhou diagnostic score tables was the highest one. With the prospective test, the area under ROC of Guangzhou diagnostic score table was 0.949, and more than any other diagnostic score table. By PCA, FHS was classified into excess fire and deficiency fire, and then classified into syndrome of flaring up of Heart (Xin) fire, syndrome of Lung (Fei)-Stomach (Wei) excess fire, syndrome of deficiency of Liver (Gan)-yin and Kidney (Shen)-yin, and syndrome of deficiency of Lung-yin from the view of viscera. In the retrospective test, the consistency with clinicians' diagnosis was 69.4%, and in the prospective test, it was 70.1%. Conclusions: The Guangzhou diagnostic score table could be used as the recommended criteria for the diagnosis of FHS. The classification of FHS was basically in conformity with the clinical situation.展开更多
Very often it so happens that the cost of operating an Intrusion Detection System (IDS) exceeds the cost of purchasing the IDS itself. In such cases, regular operation and maintenance of the system becomes expensive. ...Very often it so happens that the cost of operating an Intrusion Detection System (IDS) exceeds the cost of purchasing the IDS itself. In such cases, regular operation and maintenance of the system becomes expensive. Thus, it becomes essential to reduce the operating cost of the IDS without compromising on the performance and reliability of the IDS. Apart from the initial cost of procuring the IDS, other costs include cost of accessories required and cost of administration etc. In this paper we calculate the cost benefit tradeoffs of an IDS. We propose a method to determine the optimum operating point of the IDS. In an effort to solve the problems of the previously proposed metrics, we propose a decision tree based approach to calculate the cost of operating an IDS in a mobile ad hoc network. Mathematically and programmatically we deduce the minimum operating point of operation of an IDS and generate the receiver operating characteristic curve of the IDS. To further ascertain this, we use available network packet capture data and calculate the minimum operating cost of an IDS. The main motive behind this paper is to show that the cost of operating an IDS in a MANET can be minimized and hence the effectiveness and performance of the IDS can be maximized.展开更多
文摘Objective To evaluate the sensitivity and specificity of body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) measurements in diagnosing abdominal visceral obesity. Methods BMI, WC, and WHR were assessed in 690 Chinese adults (305 men and 385 women) and compared with magnetic resonance imaging (MRI) measurements of abdominal visceral adipose tissue (VA). Receiver operating characteristic (ROC) curves were generated and used to determine the threshold point for each anthropometric parameter. Results 1) MRI showed that 61.7% of overweight/obese individuals (BMI≥25 kg/m2) and 14.2% of normal weight (BMI<25 kg/m2) individuals had abdominal visceral obesity (VA≥100 cm2). 2) VA was positively correlated with each anthropometric variable, of which WC showed the highest correlation (r=0.73-0.77, P<0.001). 3) The best cut-off points for assessing abdominal visceral obesity were as followed: BMI of 26 kg/m2, WC of 90 cm, and WHR of 0.93, with WC being the most sensitive and specific factor. 4) Among subjects with BMI≥28 kg/m2 or WC≥95 cm, 95% of men and 90% of women appeared to have abdominal visceral obesity. Conclusion Measurements of BMI, WC, and WHR can be used in the prediction of abdominal visceral obesity, of which WC was the one with better accuracy.
基金supported by grants from the National Natural Science Foundation of China(81301275,81471736 and 81671760)the National Science and Technology Pillar Program during the Twelfth Five-Year Plan Period(2015BAI01B09)Heilongjiang Province Foundation for Returness(LC2013C38)
文摘BACKGROUND: The various combination of multiphase enhancement multislice spiral CT (MSCT) makes the diagno- sis of a small hepatocellular carcinoma (sHCC) on the back- ground of liver cirrhosis possible. This study was to explore whether the combination of MSCT enhancement scan and alpha-fetoprotein (AFP) level ficiency for sHCC. could increase the diagnostic ef- METHODS: This study included 35 sHCC patients and 52 cir- rhotic patients without image evidence of HCC as a control group. The diagnoses were made by three radiologists em- ploying a 5-point rating scale, with postoperative pathologic results as the gold standard. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diag- nostic value of the three MSCT combination modes (arterial phase+portal-venous phase, arterial phase+delayed phase, arterial phase+portal-venous phase+delayed phase) and AFP levels for sHCC on the background of liver cirrhosis. RESULTS: The area under ROC curve (AUC), sensitivity, and specificity of the combination of arterial phase+portal- venous phase+delayed phase were 0.93, 93%, and 82%, respectively. The average AUC of the arterial phase+portal- venous phase+delayed phase combination was significantly greater than that of the arterial phase+portal-venous phase (AUC=0.84, P=0.01) and arterial phase+delayed phase (AUC=0.85, P=0.03). Arterial phase+portal-venous phase had a smaller AUC (0.84) than arterial phase+delayed phase (0.85), but the difference was insignificant (P=0.15). After combining MSCT enhancement scan with AFP, the AUC, sensitivity, and specificity were 0.95, 94%, and 83%, respectively, indicating a greatly increased diagnostic efficiency for sHCC. CONCLUSIONS: The combination of AFP and 3 phases MSCT enhancement scan could increase the diagnostic efficiency for sHCC on the background of liver cirrhosis. The application of ROC curve analysis has provided a new method and reference in HCC diagnosis.
文摘Objective: To determine the endemic values of cutaneous leishmaniasis in different cities of Fars province, Iran. Methods: Totally, 29 201 cases registered from 2010 to 2015 in Iranian Fars province were selected, and the endemic values of cutaneous leishmaniasis were determined by retrospective clusters derived from spatiotemporal permutation modeling on a time-series design. The accuracy of the values was assessed using receiver operating characteristic(ROC) curve. SPSS version 22, Arc GIS, and ITSM 2002 software tools were used for analysis. Results: Nine statistically significant retrospective clusters(P<0.05) resulted in finding seven significant and accurate endemic values(P<0.1). These valid endemic scores were generalized to the other 18 cities based on 6 different climates in the province. Conclusions: Retrospectively detected clusters with the help of ROC curve analysis could help determine cutaneous leishmaniasis endemic values which are essential for future prediction and prevention policies in the area.
文摘Aim: To assess that metabolic status of spermatozoa could provide a useful tool for evaluation of semen quality. Methods: The accuracy of the spectrophotometric application of the resazurin reduction assay was assessed using receiver operating characteristic (ROC) analysis. Results: Areas under ROC curves (AUC) for motile sperm concentration and sperm index (SI) (sperm concentration multiplied by the square root of percentage sperm motility multiplied by the percentage normal sperm morphology) were 0.922. The best discrimination between poor and good semen samples according to the SI was achieved at a cut-off point of A610 = 0.209, where high sensitivity (94.1%) and specificity (91.7%) were calculated. The assay was less accurate when motile sperm concentration was used as the criterion value, yielding sensitivity of 88.2% and specificity of 87.5%, respectively. Likelihood ratios (LR) indicate that absorbances lower than 0.209 were at least 11.3 times as likely to be found in good semen samples than those in poor according to the SI, whereas in the case of motile sperm concentration, the LR was calculated to be 7.06. Conclusion: These results show that the resazurin reduction assay combined with spectrophotometry is an accurate method of assessing the quality of boar semen.
文摘Objective(s): Laryngeal inflammations lead to voice disorders. Medical conditions such as chronic laryngitis, gastroesophageal reflux, laryngopharyngeal reflux, Reinke edema and/or vocal folds hemorrhage, result in diverse symptoms including chronic cough, throat cleaning and dysphonia (e.g. hoarseness). In turn, the dysphonic symptoms can be evaluated via subjective and objective procedures. The objective procedures usually include self-perceived questionnaires like the Voice Handicap Index (VHI). Studies reported that VHI can distinguish objectively dysphonic and non-dysphonic populations using the cut-off points of Receiver Operating Characteristic Curves. The purpose of this study was to calculate the cut-off points for individuals exhibiting voice symptoms which had been developed from laryngeal inflammatory diseases in Greece. Methods: One hundred and twelve participants (90 non-dysphonic and 22 dysphonic) filled in the Hellenic Voice Handicap Index (VHI) and the Greek translated version of Voice Evaluation Template (VEF) were administrated. All subjects were evaluated by an Otolaryngologist and a Speech-Language Pathologist. Results: The group with voice disorders exhibited higher VHI scores (in total and in its 3 subdomains) compared to non-dysphonic subgroup. Statistical significant differences were found for all VHI’s total cut-off point of 19.50 (sensitivity: 0.882, 1-specificity: 0.011) and for its three subdomains [functional 6.50 (sensitivity = 0.636, and 1-specificity = 0.022);physical 9.50 (sensitivity = 0.636, and 1-specificity = 0.000);emotional 6.50 (sensitivity = 0.455, and 1-specificity = 0.133)]. Conclusion: The preliminary results showed that VHI could discriminate individuals having voice disorders from laryngeal inflammations. The Voice Handicap Index can be used as a primary health care tool and a self-monitoring procedure in acute and sub-acute phases of the laryngeal inflammation.
文摘Aim:To assess that metabolic status of spermatozoa could provide a useful tool for evaluation of semen quality. Methods:The accuracy of the spectrophotometric application of the resazurm reduction assay was assessed using receiver operating characteristic(ROC)analysis.Results:Areas under ROC curves(AUC)for motile sperm concen- tration and sperm index(SI)(sperm concentration multiplied by the square root of percentage sperm motility multi- plied by the percentage normal sperm morphology)were 0.922.The best discrimination between poor and good semen samples according to the SI was achieved at a cut-off point of A_(610)=0.209,where high sensitivity(94.1%)and specificity(91.7%)were calculated.The assay was less accurate when motile sperm concentration was used as the criterion value,vielding sensitivity of 88.2% and specificity of 87.5%,respectively,Likelihood ratios(LR)indicate that absorbances lower than 0.209 were at least 11.3 times as likely to be found in good semen samples than those in poor according to the SI,whereas in the case of motile sperm concentration,the LR was calculated to be 7.06.Conclusion: These results show that the resazurin reduction assay combined with spectrophotometry is an accurate method of assessing the quality of boar semen.
文摘目的:甲状腺功能障碍性视神经病变(dysthyroid optic neuropathy,DON)严重危害甲状腺相关眼病患者视力。本研究观察DON患者的视觉功能改变,并评价DON检测指标的诊断价值。方法:回顾性分析2017年1月至2019年12月在中南大学湘雅医院就诊的49例DON患者(98眼)的临床资料。所有患者均行最佳矫正视力(best corrected visual acuity,BCVA)、Humphrey视野、视觉诱发电位(visual evoked potential,VEP)和对比敏感度检测。将98眼分为DON组(45眼)和非DON组(53眼)。采用t检验比较2组患者上述各项检测的相关指标,受试者操作特征(receiver operating characteristic,ROC)曲线分析各指标的敏感度和特异度。结果:DON组的BCVA和视野指数(visual field index,VFI)均显著低于非DON组(均P<0.05),平均缺损(mean deviation,MD)和模式标准偏差(pattern standard deviation,PSD)均显著高于非DON组(均P<0.05)。DON组的低频对比敏感度(low frequency contrast sensitivity,CSL)、中频对比敏感度(medium frequency contrast sensitivity,CSM)、高频对比敏感度(high frequency contrast sensitivity,CSH)均明显低于非DON组(均P<0.05),CSH尤为明显。在15°、30°和60°空间频率时,与非DON组比较,DON组的N135波幅显著降低,N75波、P100波、N135波的潜伏期显著延长(均P<0.05);在15°和30°空间频率时,DON组较非DON组P100波幅明显降低(均P<0.05)。ROC曲线分析结果显示:VFI、CSL、CSM、CSH和15°P100波幅诊断DON的曲线下面积(area under the curve,AUC)分别为0.812、0.841、0.880、0.784和0.791,以CSM的敏感度和特异度最高。结论:DON患者的视觉功能均存在不同程度的受损。VFI、CSL、CSM、CSH和15°P100波幅可能成为早期诊断DON的有效指标。
文摘Background: To combine dinicopathological characteristics associated with lymph node metastasis for submucosal gastric cancer into a nomogram. Methods: We retrospectively analyzed 262 patients with submucosal gastric cancer who underwent D2 gastrectomy between 1996 and 2012. The relationship between lymph node metastasis and clinicopathological features was statistically analyzed. With multivariate logistic regression analysis, we made a nomogram to predict the possibility of lymph node metastasis. Receiver operating characteristic (ROC) analysis was also performed to assess the predictive value of the model. Discrimination and calibration were performed using internal validation. Results: A total number of 48 (18.3%) patients with submucosal gastric cancer have pathologically lymph node metastasis. For submucosal gastric carcinoma, lymph node metastasis was associated with age, tumor location, macroscopic type, size, differentiation, histology, the existence of ulcer and lymphovascular invasion in univariate analysis (all P〈0.05). The multivariate logistic old, macroscopic type III or mixed, undifferentiated type, regression analysis identified that age _〈50 years and presence of lymphovascular invasion were independent risk factors of lymph node metastasis in submucosal gastric cancer (all P〈0.05). We constructed a predicting nomogram with all these factors for lymph node metastasis in submucosal gastric cancer with good discrimination [area under the curve (AUC) =0.844]. Internal validation demonstrated a good discrimination power that the actual probability corresponds closely with the predicted probability. Conclusions: We developed a nomogram to predict the rate of lymph node metastasis for submucosal gastric cancer. With good discrimination and internal validation, the nomogram improved individualized predictions for assisting clinicians to make appropriated treatment decision for submucosal gastric cancer patients.
基金This study was supported by grants from the National Natural Science Foundation of China (No. 81101043), Natural Science Foundation of Jiangsu Province (No. BK2011178), and the Priority Academic Program Development of Jiangsu Higher Education institutions.
文摘Along with the development of digital X-ray imaging technology, a new, economical and practicalpaper-based output system gradually emerged. To reduce cost, more and more radiologic institutions began to change from film copies to lower-priced paper prints for documenting radiologic findings.Therefore, laser paper printers are frequently used as an alternative to duplicating film though the use of printed images is not yet widespread. The aim of this study was to compare the practical value of high-resolution paper printer with dry film copies for detecting small solitary pulmonary nodules (SPNs).
基金Supported by the National Natural Science Foundation of China(No.81273817)the Program of Guangdong Province Administration of Traditional Chinese Medicine(No.20121225)
文摘Objective: To establish the diagnostic quantitative criteria for fire-heat syndrome (FHS) of Chinese medicine (CM) based on the receiver operating characteristic (ROC) curve and principal component analysis (PCA). Methods: The symptoms and signs of FHS cases and healthy subjects from Guangzhou, Henan and Hunan of China were collected through questionnaire, and the diagnostic quantitative score tables were established for the three regions, respectively, with the method of maximum likelihood analysis. The homogeneity test was then performed on the diagnostic score tables for the three regions with ROC curve, and the diagnostic efficiency of diagnostic score tables for the three regions was compared with the prospective test and retrospective test. The method of PCA was adopted to obtain the analysis matrix for classifying the tapes of FHS. Results: Twenty-seven elements of FHS were confirmed through Chi-square test, and the diagnostic score tables for the three regions were established with the method of maximum likelihood analysis on the basis of the collected case data. According to the ROC curve test, the areas under ROC curve of Guangzhou diagnostic score table assessment with candidates in Guangzhou, Henan and Hunan were 0.998, 0.961 and 0.956, respectively. It showed that the diagnostic efficiency of Guangzhou diagnostic score tables was the highest one. With the prospective test, the area under ROC of Guangzhou diagnostic score table was 0.949, and more than any other diagnostic score table. By PCA, FHS was classified into excess fire and deficiency fire, and then classified into syndrome of flaring up of Heart (Xin) fire, syndrome of Lung (Fei)-Stomach (Wei) excess fire, syndrome of deficiency of Liver (Gan)-yin and Kidney (Shen)-yin, and syndrome of deficiency of Lung-yin from the view of viscera. In the retrospective test, the consistency with clinicians' diagnosis was 69.4%, and in the prospective test, it was 70.1%. Conclusions: The Guangzhou diagnostic score table could be used as the recommended criteria for the diagnosis of FHS. The classification of FHS was basically in conformity with the clinical situation.
文摘Very often it so happens that the cost of operating an Intrusion Detection System (IDS) exceeds the cost of purchasing the IDS itself. In such cases, regular operation and maintenance of the system becomes expensive. Thus, it becomes essential to reduce the operating cost of the IDS without compromising on the performance and reliability of the IDS. Apart from the initial cost of procuring the IDS, other costs include cost of accessories required and cost of administration etc. In this paper we calculate the cost benefit tradeoffs of an IDS. We propose a method to determine the optimum operating point of the IDS. In an effort to solve the problems of the previously proposed metrics, we propose a decision tree based approach to calculate the cost of operating an IDS in a mobile ad hoc network. Mathematically and programmatically we deduce the minimum operating point of operation of an IDS and generate the receiver operating characteristic curve of the IDS. To further ascertain this, we use available network packet capture data and calculate the minimum operating cost of an IDS. The main motive behind this paper is to show that the cost of operating an IDS in a MANET can be minimized and hence the effectiveness and performance of the IDS can be maximized.
文摘目的探讨肾小管及肾小球相关标志物在2型糖尿病(type 2 diabetes mellitus,T2DM)患者不同肾损伤阶段的诊断价值。方法选取于2018年4月1日至2019年10月31日入住首都医科大学附属北京同仁医院内分泌科的T2DM患者272例,完善临床生化指标及尿蛋白四项:尿微量白蛋白/肌酐(urinary albumin to creatinine ratio,ACR)、α1-微球蛋白/肌酐(urinary α1-microglobulin to creatinine ratio,UA1CR)、免疫球蛋白G/肌酐(urinary immunoglobulin G to creatinine ratio,UIGG)、转铁蛋白/肌酐(urinary transferrin to creatinine ratio,UTRF);进行眼底照相、核医学99mTc-EC检测肾有效血浆流量(effective renal plasma flow,ERPF)和99mTc-DTPA检测肾小球滤过率(glomerular filtration rate,GFR)。根据ACR和眼底检查结果分为4组:正常蛋白尿无糖尿病视网膜病变(diabetic retinopathy,DR)132例,即对照组(ACR≤30 mg/g);正常蛋白尿合并DR 32例,为糖尿病肾病(diabetic kidney disease,DKD)前期组;微量蛋白尿组78例(30<ACR≤300 mg/g)和大量蛋白尿组30例(ACR>300 mg/g)。比较四组间尿蛋白四项和ERPF、GFR的水平,通过受试者工作特征(receiver operating characteristic,ROC)曲线评价上述各指标在不同肾损伤阶段的诊断价值。结果尿蛋白四项和ERPF、GFR的水平在不同组间差异有统计学意义(P<0.05)。在尿蛋白正常组中,DR组中肾小管功能标志物UA1CR较对照组明显升高(P<0.01);肾小球功能标志物ACR、UTRF和GFR在两组间差异无统计学意义(P>0.05),DR组UIGG较对照组升高(P<0.01)。在微量蛋白尿组和大量蛋白尿组,尿蛋白四项随肾损伤程度增加而增加,而ERPF和GFR随肾损伤程度增加而降低。ROC曲线分析显示,在尿蛋白排出正常的T2DM患者中合并DR组中肾小管功能标志物UA1CR和ERPF的曲线下面积(area under the curve,AUC)分别为68.2%(P<0.01)和60.5%(P<0.05),而肾小球功能标志物ACR和GFR的AUC均小于60%,差异无统计学意义(P>0.05)。尿蛋白四项及GFR在微量和大量蛋白尿组的AUC均大于60%(P<0.05),ERPF在大量蛋白尿组AUC为67.2%(P<0.05)。结论T2DM极早期微血管改变即ACR正常仅有DR时,肾小管标志物UA1CR先于肾小球标志物ACR和GFR发生变化。肾损伤早期,肾小管标志物诊断效能优于肾小球;肾损伤后期,肾小球标志物诊断效能优于肾小管。提示DKD肾小管功能的改变可能早于肾小球。