Objective:To investigate the predictive value of quantitative parameters of dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) in lymph node metastasis of breast cancer.Methods:A retrospective study was conducted on 98 breast cancer patients admitted to our hospital from Jan. 2021 to Dec. 2022. All patients underwent DCE-MRI before surgery and were followed up for 2 years. Finally, 16 cases of lymph node metastasis were confirmed and included in the metastasis group, and the remaining 82 cases without metastasis were included in the non- metastasis group. The clinical data, preoperative routine MRI features and DCE-MRI quantitative parameters of the two groups were analyzed and compared, and the predictive value of DCE-MRI quantitative parameters was analyzed by receiver operating characteristic curve (ROC) .Results:There was no statistically significant difference in age, course of disease and pathological type between the two groups ( t=0.65, 1.43, χ2=1.33, P>0.05) ; The proportion of patients with middle or high pathological grade in metastasis group was higher than that in non-metastasis group ( χ2=11.29, P<0.05). The maximum diameter, shape, internal enhancement pattern and time intensity curve type showed no statistically significant difference ( t=0.54, χ2=3.51, 0.67, 0.42, P>0.05) ; The proportion of patients with blurred edge features in metastasis group was higher than that in the other group ( χ2=4.53, P<0.05). The volume transfer constant (K trans) and reflux rate constant (Kep) in the metastasis group were higher than those in the other group ( t=2.97, 3.22, P<0.05), and extracellular space volume ratio (Ve) showed no statistically significant difference ( t=0.42, P>0.05). Receiver operating characteristic curve (ROC) results showed that the area under the curve (AUC) of K trans, Kep and their combined prediction of breast cancer lymph node metastasis was 0.758, 0.710 and 0.764, respectively, and the sensitivity was 56.25%, 42.75% and 62.50%, respectively. The specificity was 86.59%, 89.02% and 86.59% (all P<0.05) . Conclusions:Quantitative parameters of DCE-MRI can be used to predict lymph node metastasis of breast cancer, among which K trans, Kep and their combination are more effective in diagnosis.

Objective:To investigate the predictive value of quantitative parameters of dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) in lymph node metastasis of breast cancer.Methods:A retrospective study was conducted on 98 breast cancer patients admitted to our hospital from Jan. 2021 to Dec. 2022. All patients underwent DCE-MRI before surgery and were followed up for 2 years. Finally, 16 cases of lymph node metastasis were confirmed and included in the metastasis group, and the remaining 82 cases without metastasis were included in the non- metastasis group. The clinical data, preoperative routine MRI features and DCE-MRI quantitative parameters of the two groups were analyzed and compared, and the predictive value of DCE-MRI quantitative parameters was analyzed by receiver operating characteristic curve (ROC) .Results:There was no statistically significant difference in age, course of disease and pathological type between the two groups ( t=0.65, 1.43, χ2=1.33, P>0.05) ; The proportion of patients with middle or high pathological grade in metastasis group was higher than that in non-metastasis group ( χ2=11.29, P<0.05). The maximum diameter, shape, internal enhancement pattern and time intensity curve type showed no statistically significant difference ( t=0.54, χ2=3.51, 0.67, 0.42, P>0.05) ; The proportion of patients with blurred edge features in metastasis group was higher than that in the other group ( χ2=4.53, P<0.05). The volume transfer constant (K trans) and reflux rate constant (Kep) in the metastasis group were higher than those in the other group ( t=2.97, 3.22, P<0.05), and extracellular space volume ratio (Ve) showed no statistically significant difference ( t=0.42, P>0.05). Receiver operating characteristic curve (ROC) results showed that the area under the curve (AUC) of K trans, Kep and their combined prediction of breast cancer lymph node metastasis was 0.758, 0.710 and 0.764, respectively, and the sensitivity was 56.25%, 42.75% and 62.50%, respectively. The specificity was 86.59%, 89.02% and 86.59% (all P<0.05) . Conclusions:Quantitative parameters of DCE-MRI can be used to predict lymph node metastasis of breast cancer, among which K trans, Kep and their combination are more effective in diagnosis.

Objective:To analyze the application effects of case-based learning (CBL) + Seminar teaching method based on Toulmin model in the education and teaching of clinical medicine innovation class.Methods:A total of 60 students from the clinical medicine innovation class at The Second Affiliated Hospital of Guangzhou Medical University from September 2021 to September 2023 were selected as research objects. These students were divided into control group ( n=30) and research group ( n=30) according to different teaching programs. The traditional teaching method was adopted in the control group, and the CBL + Seminar teaching method based on Toulmin model was adopted in the research group. The two groups were compared in terms of clinical knowledge, clinical skill, and clinical case analysis scores; changes in clinical thinking ability after teaching; and satisfaction with the teaching process. SPSS 22.0 was used for t-test and chi-square test. Results:The research group significantly outperformed the control group in clinical knowledge [(89.59±3.46) points vs. (83.23±3.02) points], clinical skill [(88.87±3.23) points vs. (83.62±3.13) points], and clinical case analysis [(89.73±3.51) points vs. (82.62±3.19) points] ( t=7.58, 6.39, 8.21, P<0.001). The clinical thinking ability after teaching was significantly higher in the research group compared to the control group [(258.49±13.36) points vs. (242.56±13.02) points] ( t=4.67, P<0.001). The overall satisfaction rate of teaching was significantly higher in the research group compared to the control group (100.00% vs. 80.00%, χ2=4.63, P=0.031). Conclusions:The CBL + Seminar teaching method based on Toulmin model can effectively improve student learning performance and clinical thinking ability, demonstrating a promising application value in the education and teaching of clinical medicine innovation class.

Objective:To analyze the application effects of case-based learning (CBL) + Seminar teaching method based on Toulmin model in the education and teaching of clinical medicine innovation class.Methods:A total of 60 students from the clinical medicine innovation class at The Second Affiliated Hospital of Guangzhou Medical University from September 2021 to September 2023 were selected as research objects. These students were divided into control group ( n=30) and research group ( n=30) according to different teaching programs. The traditional teaching method was adopted in the control group, and the CBL + Seminar teaching method based on Toulmin model was adopted in the research group. The two groups were compared in terms of clinical knowledge, clinical skill, and clinical case analysis scores; changes in clinical thinking ability after teaching; and satisfaction with the teaching process. SPSS 22.0 was used for t-test and chi-square test. Results:The research group significantly outperformed the control group in clinical knowledge [(89.59±3.46) points vs. (83.23±3.02) points], clinical skill [(88.87±3.23) points vs. (83.62±3.13) points], and clinical case analysis [(89.73±3.51) points vs. (82.62±3.19) points] ( t=7.58, 6.39, 8.21, P<0.001). The clinical thinking ability after teaching was significantly higher in the research group compared to the control group [(258.49±13.36) points vs. (242.56±13.02) points] ( t=4.67, P<0.001). The overall satisfaction rate of teaching was significantly higher in the research group compared to the control group (100.00% vs. 80.00%, χ2=4.63, P=0.031). Conclusions:The CBL + Seminar teaching method based on Toulmin model can effectively improve student learning performance and clinical thinking ability, demonstrating a promising application value in the education and teaching of clinical medicine innovation class.

Objective To propose a classification method for ultrasound images of pedicle screw canals based on radiomics analysis,and to evaluate the integrity of the screw canal.Methods With thoracolumbar spine specimens from 4 fresh cadavers,50 pedicle screw canals were pre-established and ultrasound images of the canals were acquired.A total of 2 000 images(1 000 intact and 1 000 damaged canal samples)were selected.The dataset was randomly divided in a 4∶1 ratio using 5-fold cross-validation to form training and testing sets(consisting of 1 600 and 400 samples,respectively).Firstly,the optimal radius of the region of interest was identified using the Otsu's thresholding method,followed by feature extraction using pyradiomics.Principal component analysis and the least absolute shrinkage and selection operator algorithm were employed for dimensionality reduction and feature selection,respectively.Subsequently,3 machine learning models(support vector machine[SVM],logistic regression,and random forest)and 3 deep learning models(visual geometry group[VGG],ResNet,and Transformer)were used to classify the ultrasound images.The performance of each model was evaluated using accuracy.Results With a region of interest radius of 230 pixels,the SVM model achieved the highest classification accuracy of 96.25%.The accuracy of the VGG model was only 51.29%,while the accuracies of the logistic regression,random forest,ResNet,and Transformer models were 85.50%,80.75%,80.17%,and 75.18%,respectively.Conclusion For ultrasound images of pedicle screw canals,the machine learning model performs better than the deep learning model as a whole,and the SVM model has the best classification performance,which can be used to assist physicians in diagnosis.

Objective:To investigate the value of mammography and MRI parameters combined with red cell distribution width to lymphocyte ratio (RLR) in predicting recurrence and metastasis of breast cancer after modified radical surgery.Methods:104 female breast cancer patients who received improved radical surgery in Jiande First People’s Hospital from Jun. 2021 to Dec. 2023 were included as the study objects. The Japanese MGU-1000D MAMMOREX Pe.ru.ru DIGITAL mammography machine was used to examine each subject before surgery, and the X-ray signs of the primary tumor lesion were recorded, including maximum diameter, breast density, calcification, mass morphology, vascular signs and tumor margin. The primary tumor was evaluated by MRI using a MAGNETOM Verio magnetic resonance imaging machine and a dedicated breast examination coil, the apparent diffusion coefficient (ADC) value was measured and automatically calculated, and the RLR was recorded.Results:There were 31 patients with recurrence and metastasis and 73 patients without recurrence or metastasis. The proportion of patients with clinical stage III and Ki67 level > 14% in postoperative recurrence and metastasis group was significantly higher than that in patients without recurrence and metastasis. The proportion of patients with calcification, vascular thickening, increase and burr at the edge of mass in the recurrence and metastasis group was significantly higher than that in the patients without recurrence or metastasis. The ADC value of patients with recurrence and metastasis after breast cancer surgery was 0.93±0.12, and that of patients without recurrence and metastasis was 1.08±0.15, the former was significantly lower than the latter, and the difference was statistically significant ( t=5.64, P<0.001). The RLR of peripheral blood in patients with recurrence and metastasis after breast cancer surgery was 21.36±2.39, and that of patients without recurrence and metastasis was 19.93±2.14, the former was significantly higher than the latter, and the difference was statistically significant ( t=4.37, P<0.001). Multivariate Logistic regression analysis showed that axillary lymph node metastasis, vascularization, thickening, burr on tumor edge, small ADC value and large peripheral blood RLR were independent risk factors for recurrence and metastasis after breast cancer surgery ( P<0.05). ROC curve results showed that the area under the curve of the logistic regression model based on the above factors was 0.860 (0.798-0.921), the sensitivity was 80.4%, and the specificity was 81.8%. Conclusion:Mammogram and MRI parameters combined with peripheral blood RLR level have certain value in predicting recurrence and metastasis after modified radical breast cancer surgery.

Objective:To explore potential predictors of refractory Mycoplasma pneumoniae pneumonia (RMPP) in early stage. Methods:The prospective multicenter study was conducted in Zhejiang, China from May 1 st, 2019 to January 31 st, 2020. A total of 1 428 patients with fever >48 hours to <120 hours were studied. Their clinical data and oral pharyngeal swab samples were collected; Mycoplasma pneumoniae DNA in pharyngeal swab specimens was detected. Patients with positive Mycoplasma pneumoniae DNA results underwent a series of tests, including chest X-ray, complete blood count, C-reactive protein, lactate dehydrogenase (LDH), and procalcitonin. According to the occurrence of RMPP, the patients were divided into two groups, RMPP group and general Mycoplasma pneumoniae pneumonia (GMPP) group. Measurement data between the 2 groups were compared using Mann-Whitney U test. Logistic regression analyses were used to examine the associations between clinical data and RMPP. Receiver operating characteristic (ROC) curves were used to analyse the power of the markers for predicting RMPP. Results:A total of 1 428 patients finished the study, with 801 boys and 627 girls, aged 4.3 (2.7, 6.3) years. Mycoplasma pneumoniae DNA was positive in 534 cases (37.4%), of whom 446 cases (83.5%) were diagnosed with Mycoplasma pneumoniae pneumonia, including 251 boys and 195 girls, aged 5.2 (3.3, 6.9) years. Macrolides-resistant variation was positive in 410 cases (91.9%). Fifty-five cases were with RMPP, 391 cases with GMPP. The peak body temperature before the first visit and LDH levels in RMPP patients were higher than that in GMPP patients (39.6 (39.1, 40.0) vs. 39.2 (38.9, 39.7) ℃, 333 (279, 392) vs. 311 (259, 359) U/L, both P<0.05). Logistic regression showed the prediction probability π=exp (-29.7+0.667×Peak body temperature (℃)+0.004×LDH (U/L))/(1+exp (-29.7+0.667×Peak body temperature (℃)+0.004 × LDH (U/L))), the cut-off value to predict RMPP was 0.12, with a consensus of probability forecast of 0.89, sensitivity of 0.89, and specificity of 0.67; and the area under ROC curve was 0.682 (95% CI 0.593-0.771, P<0.01). Conclusion:In MPP patients with fever over 48 to <120 hours, a prediction probability π of RMPP can be calculated based on the peak body temperature and LDH level before the first visit, which can facilitate early identification of RMPP.

Objective:To evaluate the pathological features of a heart failure with preserved ejection fraction(HFpEF) model, which is established by spontaneously hypertensive rats (SHR) through high-fat diet and diabetic factors.Methods:Twenty specific pathogen-free grade(SPF grade) and 14-week-old SHR rats were randomly divided into SHR group (normal diet) and HFpEF group [high-fat diet combined with intraperitoneal injection of streptozotocin (STZ, 25 mg/kg) were used to create a diabetic complex model] with 10 rats in each group. Ten SPF and 14-week-old WKY rats with the same genetic background were set as blank control group (WKY group). All rats were fed for 8 weeks. Echocardiography was performed to measure cardiac parameters: peak velocity of early diastolic mitral inflow(E), peak velocity of late diastolic mitral inflow(A), and the early diastolic mitral annulus e′ in the same cardiac cycle, left atrial ejection fraction (LAEF), left ventricular ejection fraction (LVEF), left atrial diameter, right atrial diameter and interventricular septal thickness(IVST). Serological testing included glucose (GLU) and glycosylated serum protein (GSP); Enzyme-linked immunoassay (ELISA) testing included insulin (INS), glucagon (PG), C-peptide (CP), leptin (LEP), atrial natriuretic peptide (ANP) and B-type brain natriuretic peptide (BNP). The rat heart tissue was stained with HE, and the morphological changes of atrial/ventricular tissue were observed under an optical microscope.Results:The pathological characteristics of HFpEF was established in SHR rats fed with high fat and diabetes. Echocardiography showed that compared with the WKY group, the values of E, E/A and E/e′ in the HFpEF group were significantly increased (all P<0.01), and e′and LAEF were significantly reduced (all P<0.01). In the HFpEF group, the anteroposterior and tranverse dimensions of the left atrium and the long-axis dimension of the right atrium increased to varying degrees (all P<0.05), and the IVST was also significantly increased ( P<0.01). At the same time, atrial wall was thickened obviously, myocardial cells were disordered, and myocardial fibers were broken. Compared with the WKY group, the levels of serum markers ANP and BNP in HFpEF group were significantly increased (all P<0.01), and the levels of serum insulin-related indicators INS, PG, CP, LEP, GSP, and GLU increased to varying degrees (all P<0.01). Conclusions:The composite model established by SHR rats through high-fat diet and diabetic factors can simulate the Doppler echocardiographic changes and pathological features of HFpEF, as well as abnormal changes in serum related markers and insulin indicators.

To explore the safety and efficacy for radiofrequency ablation of paroxysmal supraventricular tachycardia (PSVT) guided by Carto Univu three-dimensional mapping system.
 Methods: A total of 99 patients with PSVT underwent radiofrequency catheter ablation (RFCA) were assigned to a Carto Univu group (51 patients) and a two-dimensional X-ray group (48 patients) according to the mapping method. The operation time, X-ray exposure time, X-ray exposure dose, dose area product (DAP), operation success rate and complication rate were compared between the two groups.
 Results: The Carto Univu group and the two-dimensional X-ray group were not significant difference in the operation time, the X-ray exposure time of placing catheter, the X-ray DAP of placing catheter, the number of discharge, the discharge power, and the total discharge time (P>0.05). The mapping and ablation time, total exposure time, mapping and ablation DAP and total DAP in the Carto Univu group were significantly lower than those in the two-dimensional X-ray group (P<0.01). In the right accessory pathway cases, the mapping and ablation DAP and the total DAP in the Carto Univu group decreased compared with X-ray group (P<0.05), but it decreased more profound (P<0.01) in the left accessory pathway cases and the dual atrioventricular nodal pathways cases. Seven cases in the Carto Univu group achieved "zero X-ray", including 5 cases of the dual atrioventricular nodal pathways and 2 cases of the left accessory pathway. The immediate success rate for the two groups was 100%. After 3-12 months of follow-up, there was no recurrence in the Carto Univu group but 3 suspected recurrences in the two-dimensional X-ray group. In addition, no complications occurred in the two groups. 
 Conclusion: Carto Univu electroanatomic mapping system can guide PSVT safely and effectively during radiofrequency ablation and reduce radiation exposure to both doctors and patients. It is especially suitable for dual atrioventricular nodal pathways, which may even achieve "zero X-ray". Perhaps Carto Univu will be the first choice for RFCA of dual atrioventricular nodal pathways.
Catheter Ablation ; instrumentation ; methods ; Humans ; Imaging, Three-Dimensional ; instrumentation ; methods ; Operative Time ; Radiation Exposure ; prevention & control ; statistics & numerical data ; Radiography ; statistics & numerical data ; Recurrence ; Tachycardia, Supraventricular ; diagnostic imaging ; surgery ; Treatment Outcome

Objective To evaluate the value of magnetic resonance black-blood thrombus imaging (BTI) of the stage of disease in intracranial venous and sinus thrombosis(CVT).Methods From June 2015 to October 2016,37 patients with CVT diagnosed with routine imaging examinations in Beijing Xuanwu Hospital,Capital Medical University were enrolled prospectively,and they also underwent BTI examination.The patients were randomly divided into either a acute group (≤14 d,n=23) or a chronic group (>15 d,n=14) according to the time from the onset of symptoms to BTI.Signal to noise ratio(SNR) and contrast to noise ratio(CNR) difference between acute and chronic CVT groups were compared.The magnetic resonance venography (MRV) examination was used as a reference to calculate the accuracy of BTI on per-segment level.Results (1) The SNR and CNR of thrombosis in the acute group and chronic group were 206±97 and 94±41,201±96 and 86±40,respectively.There was significant difference between two groups (t=4.9 and 5.0 respectively;all P<0.01).(2) In 37 patients with CVT,the thrombi in 159 cerebral veins and venous sinus segments were detected with MRV.BTI identified the thrombi accurately in 152 vascular segments,and the thrombi in 352 vascular segments were eliminated.The diagnostic sensitivity and specificity were 95.6% (152/159) and 98.0% (352/359) respectively.Conclusion Achieving direct angiography of cerebral venous thrombosis,BTI technique can accurately differentiate acute or chronic thrombus.It has higher accuracy.