Objective:To explore the intimal injury of two kinds of hemostatic clips under different clamping forces, and to optimize and verify the calculation formula of minimum occlusion force (MOF), so as to provide theoretical basis for selecting appropriate hemostatic clips to reduce vascular injury.Methods:A total of 96 male SD rats with body weight ranging from 280 to 300 g (Animal Experimental Center of Shanxi Medical University) were randomly assigned to metal hemostatic clip group ( n=48) and disposable hemostatic clip group ( n=48) by random number table method. Each group was further divided into four subgroups with clamping forces of 0.3, 0.6, 0.9 and 1.2 N for abdominal aortic injury experiments. The damage to the vascular intima was observed under a scanning electron microscope. A vascular closure model was established for mathematical analysis to derive the theoretical calculation formula of the arterial blood management factor (MOF). According to blood pressure (BP), blood vessel diameter (D) and hemostatic clamp width (W), the average values of theoretical and actual MOF data were analyzed by paired t test to verify the accuracy of the formula. From January 2021 to December 2022, six patients (with 12 branch arteries) who presented with oral and maxillofacial malignancies at the Department of Oral and Maxillofacial Surgery, Shanxi Medical University School and Hospital of Stomatology, were included to validate the accuracy of the MOF formula. Results:Under electron microscopy, when the clamping force was 0.3 N, the one-time hemostatic clip caused very little damage to the vascular intima (grade 1 injury), with only a few folds being flattened. When the clamping force was 0.6 N, both types of hemostatic clips caused partial peeling of the intima surface (grade 2-3 injury). However, when the clamping force was adjusted to 0.9 and 1.2 N, the damage caused by both types of hemostatic clips was more severe (grade 3-4 injury), with large areas of intima peeling or even disappearance. In some specimens of the metal hemostatic clip group, the damage even reached the muscular layer. Vascular closure model analysis showed that MOF=2×(1/2×π×D×W×BP), the mean diameter of abdominal aorta of 24 SD rats was (1.41±0.07) mm, the blood pressure was (83.29±11.56) mmHg (1 mmHg=0.133 kPa). The theoretical MOF value was (0.096±0.015) N, the actual clamping force (ACF) was (0.095±0.012) N, there was no statistical significance between the two groups ( t=-0.35, P=0.725). In clinical application, the MOF calculation formula was used to select the appropriate hemostatic clip for 12 arteries, successfully blocking the blood flow, verifying the accuracy of the formula. Conclusions:Hemostatic clips can cause damage to the inner membrane of blood vessels, and the greater the clamping force, the more severe the damage. Disposable hemostatic clips have certain advantages in avoiding excessive damage to the inner membrane of blood vessels. The theoretical MOF calculation formula has a certain degree of reliability and can be used as a reference to select the appropriate hemostatic clip with low damage.

Objective To evaluate the value of dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)in differentiating histopathological types of brain metastases from non-small cell lung cancer(NSCLC).Methods Sixty-eight patients with brain metastases confirmed by pathology were collected,including 47 lung adenocarcinoma patients divided into a lung adenocarcinoma group and 21 lung squamous cell carcinoma patients into a lung squamous cell carcinoma group.The two groups were compared in terms of the DCE-MRI derived parameters including volume transfer constant(Ktrans),extra vascular extracellular volume fraction(Ve)and plasma volume fraction(Vp);ROC curves were used to assess the diagnostic efficacy of different quantitative parameters for the pathologic types of brain metastases from lung adenocarcinoma group or lung squamous cell carcinoma.SPSS 22.0 software was used for statistical analysis.Results The lung adenocarcinoma group had the values of Ktrans,Ve,Vp and Ve+Vp higher than those of the lung squamous cell carcinoma group,with the differences being statistically significant(all P＜0.05).ROC curve analysis results showed that Ktrans,Vp and Ve had high differential diagnosis values for the pathologic types of brain metastases from lung adenocarcinoma group or lung squamous cell carcinoma,with the AUC being 1.000,0.998 and 0.875,the optimal Youden index being 0.183 min-1,0.039 and 0.270,the sensitivity being 100.00％,100.00％and 80.56％and the specificity being 100.00％,97.06％and 80.88％,respectively.Conclusion The quantitative parameters of DCE-MRI gain advantages in the differential diagnosis of NSCLC brain metastases,and provide references for the diagnosis and treatment of brain metastases of lung cancer.[Chinese Medical Equipment Journal,2025,46(5):54-59]

Objective:To measure the radial artery (RA) diameter and explore its related factors by using optical coherence tomography (OCT).Methods:This was a cross-sectional study conducted in Cardiac Care Unit of Beijing Luhe Hospital, Capital Medical University. Patients who underwent first-ever right forearm access and OCT guided coronary intervention via right distal RA, and measurement of the whole portion of RA diameter with OCT in our center between January 2021 to December 2021 were enrolled. Following the coronary intervention, OCT was used to assess the entire RA. The RA diameter was measured from the RA ostium to 2 cm above the radial styloid process, with a 1 mm interval. Multiple linear regression analysis was performed to determine the factors related the RA diameter.Results:The study enrolled 124 patients with an age of (61.6±12.6) years, of whom 98 (79%) were male. The total length of the RA was (19.5±1.8) cm, for males (20.2±1.3) cm and females (17.2±1.2) cm. The average RA diameter was (3.13±0.50) mm, and the RA diameter at 2 to 5 cm above the radial styloid process was (2.98±0.53) mm. The average RA diameter was significantly larger for male patients than for female patients ((3.21±0.50) mm vs. (2.84±0.37) mm, P<0.001). Multiple linear regression analysis indicated that gender was significantly associated with RA diameter ( P=0.019). Conclusions:The average RA diameter measured by OCT is (3.13±0.50) mm, (2.98±0.53) mm at 2 to 5 cm above the radial styloid process. Gender is identified as a factor related to the RA diameter.

Objective To explore the value of diffusion kurtosis imaging(DKI)in the diagnosis of Parkinson's disease with mild cognitive impairment(PD-MCI)patients.Methods A total of 18 patients with Parkinson's disease cognitive normal(PDN),22 patients with PD-MCI,and 24 healthy controls(HC)were prospectively included.All participants underwent DKI,and regions of interest(ROI)were selected in the substantia nigra,red nucleus,striatum,and posterior cingulate gyrus for post-processing.The diagnostic efficacy of DKI parameters on PD patients' cognitive status was analyzed by the receiver operating characteristic(ROC)curve.Results Compared with the PDN group,the PD-MCI group had a longer disease duration and a higher H-Y stage.Compared with the HC group,the PD-MCI group showed significantly lower mean kurtosis(MK),radial kurtosis(RK),axial kurtosis(AK),and fractional anisotropy(FA)values in the substantia nigra and posterior cingulate gyrus.In the PDN group,FA and MK values in the substantia nigra were significantly decreased,while FA values in the striatum and posterior cingulate gyrus were significantly increased(P＜0.05).Compared with the PDN group,the PD-MCI group showed significantly decreased DKI parameter values in the substantia nigra and posterior cingulate gyrus,and significantly decreased RK,AK,and FA values in the striatum(P＜0.05).The FA values of striatum,posterior cingulate gyrus and joint predictors were the most effective in the diagnosis of PD-MCI and the area under the curve(AUC)were 0.826,0.853 and 0.960,respectively.Conclusion DKI can detect microstructural changes in PD patients.Microstructural alterations in the striatum and posterior cingulate gyrus have an impact on early cognitive function changes in PD patients.FA demonstrate high sensitivity and specificity in the diagnosis of PD-MCI,and the combined diagnostic efficacy across multiple regions is even higher.

Objective:To compare the treatment time stability, inter- and intra-fraction errors, and clinical target volume (CTV) to planning target volume (PTV) margin expansions under different gated window settings in deep inspiration breath hold (DIBH) radiotherapy for breast cancer, and to analyze the correlation between organ at risk (OAR) dose optimization and changes in lung volume.Methods:A retrospective analysis was conducted on 65 patients with left-sided breast cancer who received DIBH radiotherapy after modified radical mastectomy. CT simulation positioning was performed using 2 mm or 3 mm gated window for DIBH, followed by target delineation, treatment planning, and dose verification. During treatment, setup errors guided by cone beam CT (CBCT), intra-fraction monitoring errors, and treatment times were recorded. The coefficient of variation (CV) of treatment time was calculated for both gated window settings. Based on inter- and intra-fraction error distributions, the expansion distance of the CTV were determined using the van Herk formula. Dosimetric differences between DIBH and free-breathing (FB) plans for the left lung, heart, and left anterior descending coronary artery (LAD) were compared. Spearman correlation analysis was performed between the relative increase in left lung volume and the relative reduction in OAR dose. Paired t-tests were used for inter-group comparisons. Results:The mean CV of the 3 mm gated window group was 0.08±0.03, which was lower than that of the 2 mm group (0.10±0.04; t=-3.91, P<0.001). The setup errors of the 2 mm group in the X, Y, and Z directions were (1.27±1.03), (1.68±0.94), (1.90±1.25) mm, respectively-significantly smaller than those of the 3 mm group [(1.81±1.41), (2.07±1.69), (2.93±1.90) mm; t=-5.80, -2.33, -5.33; P<0.001,=0.014,<0.001). Setup errors for both groups were within the 25%-75% range and all below 5 mm. The intra-fraction deviations of the 2 mm group in the X, Y, and Z directions were (0.54±0.33), (0.79±0.44), (0.70±0.53) mm, respectively, significantly smaller than those of the 3 mm group [(0.62±0.43), (0.93±0.66), (0.87±0.67) mm; t=-3.87, -3.46, -2.71,all P<0.001). The mean intra-fraction errors of both groups were within 1 mm, with greater deviations in the Y and Z directions than those in the X direction. The CTV expansion margins for the 2 mm group in the X, Y, and Z directions were 4.21, 5.35, 5.99 mm, respectively, while those for the 3 mm group were 5.81, 6.89, 9.06 mm. Compared with FB, DIBH significantly reduced the doses to the left lung, heart, and LAD (all P<0.01). The increase in left lung volume was moderately negatively correlated with the reduction in left lung D mean ( r=-0.43, P=0.028), and highly negatively correlated with the dose reductions to the heart and LAD (both P<0.001). Conclusions:The variability in respiratory gated window settings can lead to differences in treatment time stability as well as inter- and intra-fraction errors, consequently affecting CTV-to-PTV margins. The DIBH technique demonstrates significant dosimetric benefits in reducing radiation exposure to the left lung, heart, and LAD. Volumetric expansion of the left lung is strongly and inversely correlated with the reduction in radiation dose to both the heart and LAD.

40 patients with choronic periodontitis underwent periodontal basic treatment were randomly divided into 2 groups(n=20).The patients in control group used special toothpaste and toothbrush to brush their teeth after meals,those in the experimental group brushed their teeth with special toothpaste and toothbrush in the morning,evening and after meals,and wore personalized film pressing trays containing cymene care solution while sleeping at night.Gingival bleeding,periodontal pocket depth and attachment loss were ob-served after 4,6 and 10 weeks respectively.The personalized tray combined with cymbidium reduced the depth of periodontal pocket(P＜0.05)and the rate of probing bleeding sites(P＜0.05)more effectively,and showed no statistical significance in the change of attachment loss(P＜0.05).Cymene care solution is effective in the improvement of periodontal health.

BACKGROUND:MXene-based hydrogel is a kind of nano-composite multifunctional hydrogel material,which has broad application prospects in the field of chronic wound repair,such as diabetic foot,pressure sore,cancer,and traumatic ulcer.OBJECTIVE:To review the advantages of MXene-based hydrogels and their application and related action mechanism in wound repair.METHODS:The articles included in CNKI,VIP,PubMed,and Science Direct databases were searched from January 2010 to October 2023.The key words were"MXene,hydrogel,tissue engineering application,wound repair"in Chinese and"MXene,hydrogel,wound repair"in English.Finally,70 articles that met the criteria were selected for review.RESUILTS AND CONCLUSION:MXene-based hydrogels have excellent mechanical,electrical,photo-thermal properties,biocompatibility,and antibacterial effects in wound tissue engineering,and can be combined with other organic and inorganic substances to produce greater therapeutic effects in hydrogel.MXene-based hydrogels can be applied to skin wounds in combination with wound monitoring,drug delivery and release,and photothermal therapy.Despite some progresses in the design and preparation of MXene-based hydrogel composites,they are still in the fundamental research stage.There is a lack of clinical validation regarding their effectiveness and safety,but they hold great potential for development and application.

Objective:To assess the core competencies of internal medicine residents undergoing standardized residency training and to explore the effectiveness of core competency evaluation on mobile devices.Methods:The mobile formative evaluation module was developed based on the "Xueyiku" teaching management platform. From January to December 2023, clinical teachers were asked to evaluate 150 internal medicine residents based on the "Resident Core Competency Milestone Evaluation System in China Consortium of Elite Teaching Hospitals", and the results were analyzed using non-parametric tests.Results:Among the six core competencies of internal medicine residents, professionalism received the highest score, whereas teaching skill received a lower score (97.50 vs. 90.00; H=167.31, P<0.001). Second-year residents had significantly higher scores than first-year residents (93.00 vs. 90.00; P<0.001), but similar scores to third-year residents (93.00 vs. 93.00; P>0.05). In addition, there was no significant difference in score among residents with different medical education backgrounds ( P>0.05). Conclusions:More emphasis should be placed on improving the teaching skills of internal medicine residents, along with the implementation of tiered progressive training. The mobile core competency evaluation is an effective means for assessing the comprehensive skills of residents in a timely manner.

Objective:To assess the feasibility and security the orientation of foreign bodies using a portable X-ray machine in computer-aided navigation surgery.Methods:A model with a metallic foreign body was constructed.Under the fluoroscopy of a portable X-ray machine,4 points on 2 straight lines passing through the tip of the foreign body were recorded by the navigation e-quipment,and subsequently,the midpoints of the common perpendicular segments of the 2 lines were calculated as the coordinates of the foreign body(Bilinear Method).2 operators measured the coordinates of the foreign body 10 times and compared the measured coordinates of the foreign body with the actual coordinates of the foreign body in order to analyze the accuracy of the Bilinear Method.Radiation doses to model area and operators at different locations were measured using ionizing radiation detectors.Results:The ac-curacy of the Bilinear Method for measuring foreign body coordinates was(1.98±0.77)mm,and that of the 2 operators was 1.55±0.68 and 2.40±0.36 respectively(P=0.02).The radiation dose was(221.45±50.15)μSv in the model and(4.44±1.35)μSv in the operator's chest.Conclusion:The accuracy of the coordinates of the foreign body intraoperation measured by Bilinear Method meets general clinical needs,and different operators may produce different accuracy.The radiation dose is small.

Objective To evaluate the value of dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)in differentiating histopathological types of brain metastases from non-small cell lung cancer(NSCLC).Methods Sixty-eight patients with brain metastases confirmed by pathology were collected,including 47 lung adenocarcinoma patients divided into a lung adenocarcinoma group and 21 lung squamous cell carcinoma patients into a lung squamous cell carcinoma group.The two groups were compared in terms of the DCE-MRI derived parameters including volume transfer constant(Ktrans),extra vascular extracellular volume fraction(Ve)and plasma volume fraction(Vp);ROC curves were used to assess the diagnostic efficacy of different quantitative parameters for the pathologic types of brain metastases from lung adenocarcinoma group or lung squamous cell carcinoma.SPSS 22.0 software was used for statistical analysis.Results The lung adenocarcinoma group had the values of Ktrans,Ve,Vp and Ve+Vp higher than those of the lung squamous cell carcinoma group,with the differences being statistically significant(all P＜0.05).ROC curve analysis results showed that Ktrans,Vp and Ve had high differential diagnosis values for the pathologic types of brain metastases from lung adenocarcinoma group or lung squamous cell carcinoma,with the AUC being 1.000,0.998 and 0.875,the optimal Youden index being 0.183 min-1,0.039 and 0.270,the sensitivity being 100.00％,100.00％and 80.56％and the specificity being 100.00％,97.06％and 80.88％,respectively.Conclusion The quantitative parameters of DCE-MRI gain advantages in the differential diagnosis of NSCLC brain metastases,and provide references for the diagnosis and treatment of brain metastases of lung cancer.[Chinese Medical Equipment Journal,2025,46(5):54-59]