Abstract The prevention and control of myopia in Chinese children and adolescents has become a major public health issue. While maintaining increased outdoor activity as a cornerstone intervention, there is an urgent need to explore new complementary approaches that can be effectively implemented in both indoor and outdoor settings. In recent years, environmental spatial frequency has gained increasing attention as one of the key environmental factors influencing the development and progression of myopia. Both animal studies and human research have confirmed that indoor environments lacking mid to high spatial frequency components, often characterized as "visually impoverished", can promote axial elongation and myopia through mechanisms such as disruption of retinal neural signaling, impaired accommodative function, and altered expression of related molecules. Based on the scientific consensus, it is recommended that "enriching of environmental spatial frequency" should be integrated into the myopia prevention and control framework. Following the principles of schoolled organization, family cooperation, community involvement, and student participation, specific measures are put forward in three areas：optimizing school visual settings, improving home spatial environments, and promoting healthy visual behavior. The aim is to create "visually friendly" indoor environments as an important supplement to outdoor activity, thereby providing a novel perspective and strategy for comprehensively advancing myopia prevention and control among children and adolescents.

Objective:To explore the value of ultrasound imaging characteristics combined with clinical indicators in assessing the prognosis of patients with pancreatic ductal adenocarcinoma (PDAC).Methods:A retrospective analysis was conducted for patients who underwent pancreatic contrast-enhanced ultrasound (CEUS) from September 2017 to October 2023 at Peking Union Medical College Hospital and were diagnosed with PDAC based on pathological findings. Various parameters were recorded, including CA19-9 levels, tumor size, location, morphologic features, echogenicity, presence of internal cystic components, dilatation of the main pancreatic duct, peripheral vascular invasion, CEUS characteristics, presence or absence of liver metastasis, and treatment methods. In April 2024, patient survival information was obtained through telephone follow-up or review of medical records. Based on the results of the cox regression model analysis, a nomogram model of the risk of death was developed. The receiver operating characteristic (ROC) curves were applied to evaluate the predictive efficacy of the model. The calibration curves were plotted to evaluate the accuracy of the model, and clinical decision curves were used to evaluate the clinical benefit of the model.Results:This study included a total of 207 patients with PDAC. As of April 2024, 71 patients were alive and 136 died, with a median survival time of 14 months (95% CI: 12 -17). Multivariate analysis confirmed that the elevated CA19-9 ( HR=1.689, 95% CI: 1.102-2.588), tumor size >4 cm ( HR=1.641, 95% CI: 1.159-2.322), taller-than-wide shapes ( HR=1.450, 95% CI: 1.019-2.065), incomplete hypo-enhancement ( HR=1.618, 95% CI: 1.100-2.380), and liver metastasis ( HR=1.687, 95% CI: 1.175-2.423) were independent risk factors for survival in patients with PDAC. A nomogram model was further constructed for 6-month, 12-month and 3-year survival of patients with PDAC. The areas under the ROC curve were 0.679, 0.705 and 0.815, respectively. The calibration curves suggested that the model was more accurate, and the clinical decision curves showed that the model had a better clinical benefit. Conclusion:The combined use of ultrasound imaging characteristics and clinical indicators could effectively predict the prognosis of PDAC patients. Specifically, tumor size >4 cm, taller-than-wide shapes, incomplete hypo-enhancement, elevated CA19-9, and the presence of liver metastasis are correlated with poorer survival outcomes. The nomogram model constructed on the basis of these factors can be used to assess the survival of patients with PDAC.

Objective:To clarify the safety, repair rate, durability, and risk factors for recurrent mitral regurgitation(MR) in patients with Barlow disease(BD) who total thoracoscopic minimally invasive mitral valvuloplasty(TMVP).Methods:Clinical data, mid-term and long-term outcomes of BD patients who underwent TMVP at Guangdong Provincial People's Hospital from January 2009 to June 2022 were retrospectively analyzed. Patients were divided into a group with no MR recurrence(group A) and a group with MR recurrence(group B) according to whether recurrent MR appeared in the postoperative period, and the data of the two groups of patients were compared with each other for the risk factor analysis.Results:The repair rate of TMVP was 98.4%, and no patient died perioperatively. The median follow-up time was 3.1(1.7, 5.2) years, the follow-up rate was 95.8%, and there was no patient died. As of March 2023, 112 patients developed no recurrent MR(group A), 11 patients developed recurrent MR(group B), and 2 patients in group B underwent repeated mitral valve surgery. The left atrial diameter(LAD) and left ventricular end-systolic diameter(LVESD) were higher in group B than in group A patients[LAD: (50.9±7.7)mm vs.(43.7±8.7)mm, P=0.009; LVESD: (37.1±5.5)mm vs.(33.2±4.7)mm, P=0.011], and the percentage of tendon cord rupture was higher in group B than in group A( P=0.022), while the rest of the baseline data were not statistically significant. There was no statistically significant difference between two groups in terms of the use of different surgical techniques, aortic cross-clamp time, cardiopulmonary bypass time, and operative time. Postoperative LAD, postoperative LVESD, and postoperative left ventricular end-diastolic diameter of group B patients were higher than those of group A( P<0.05). There was no statistically significant difference in perioperative and long-term complication rates between the two groups. Multifactorial Cox regression analysis revealed that advanced age( HR=1.049, 95% CI: 0.997-1.103, P=0.066) and large preoperative LVESD( HR=1.168, 95% CI: 1.053-1.295, P=0.003) were the risk factors for postoperative recurrence MR. Conclusion:Total thoracoscopic minimally invasive BD repair is safe, which has a high success rate and good long-term results. Advanced age and large preoperative LVESD are risk factors for recurrent MR in the long term.

Forensic medicine has been designated as a first-level discipline,presenting new opportunities and challenges for the development of forensic medicine.Since the 1980s,the establishment of foren-sic medicine discipline and the cultivation of high-level forensic talents have become hot topics in the development of forensic medicine in China.Since the 13th Five-Year Plan,the forensic team of Shanxi Medical University has been aiming at the forefront,proposing the development goals of"Five First-class"and the discipline development path"Six Major Achievements".It has selected benchmark disci-plines,identified gaps in disciplinary development,unified thoughts,formulated completion timelines,concentrated superior resources,assigned tasks to individuals,and created an"Organized Fill-in-the-Blank Format"forensic medicine discipline construction model with the characteristics of the new era.The construction model of forensic medicine has achieved good results in the goals,discipline frame-work,scientific research,talent cultivation,discipline team and platform construction,forming a rela-tively complete discipline construction and management system,and accumulating valuable experience for the construction of first-level discipline and high-level talent cultivation of forensic medicine.

Objective:To explore the value of ultrasound imaging characteristics combined with clinical indicators in assessing the prognosis of patients with pancreatic ductal adenocarcinoma (PDAC).Methods:A retrospective analysis was conducted for patients who underwent pancreatic contrast-enhanced ultrasound (CEUS) from September 2017 to October 2023 at Peking Union Medical College Hospital and were diagnosed with PDAC based on pathological findings. Various parameters were recorded, including CA19-9 levels, tumor size, location, morphologic features, echogenicity, presence of internal cystic components, dilatation of the main pancreatic duct, peripheral vascular invasion, CEUS characteristics, presence or absence of liver metastasis, and treatment methods. In April 2024, patient survival information was obtained through telephone follow-up or review of medical records. Based on the results of the cox regression model analysis, a nomogram model of the risk of death was developed. The receiver operating characteristic (ROC) curves were applied to evaluate the predictive efficacy of the model. The calibration curves were plotted to evaluate the accuracy of the model, and clinical decision curves were used to evaluate the clinical benefit of the model.Results:This study included a total of 207 patients with PDAC. As of April 2024, 71 patients were alive and 136 died, with a median survival time of 14 months (95% CI: 12 -17). Multivariate analysis confirmed that the elevated CA19-9 ( HR=1.689, 95% CI: 1.102-2.588), tumor size >4 cm ( HR=1.641, 95% CI: 1.159-2.322), taller-than-wide shapes ( HR=1.450, 95% CI: 1.019-2.065), incomplete hypo-enhancement ( HR=1.618, 95% CI: 1.100-2.380), and liver metastasis ( HR=1.687, 95% CI: 1.175-2.423) were independent risk factors for survival in patients with PDAC. A nomogram model was further constructed for 6-month, 12-month and 3-year survival of patients with PDAC. The areas under the ROC curve were 0.679, 0.705 and 0.815, respectively. The calibration curves suggested that the model was more accurate, and the clinical decision curves showed that the model had a better clinical benefit. Conclusion:The combined use of ultrasound imaging characteristics and clinical indicators could effectively predict the prognosis of PDAC patients. Specifically, tumor size >4 cm, taller-than-wide shapes, incomplete hypo-enhancement, elevated CA19-9, and the presence of liver metastasis are correlated with poorer survival outcomes. The nomogram model constructed on the basis of these factors can be used to assess the survival of patients with PDAC.

Ventricular assist devices(VADs)have emerged as a pivotal therapeutic option for end-stage heart failure,undergoing significant technological advancements from pneumatic membrane pumps to continuous-flow centrifugal pumps.This review provides a detailed overview of several VAD models,including HeartMate Ⅲ,EVAHEART 2,and Heart Con.The initial generation of VADs established a foundation for subsequent developments,despite the occurrence of frequent complications.The second generation of VADs demonstrated a notable improvement in patient prognosis but carried the risk of ventricular collapse.The third generation of VADs represents a further reduction in size,incorporating magnetic levitation technology to enhance durability and blood compatibility.In the future,the development of VADs will focus on better emulating the physiological function of the native heart,improving pulsatility,and extending device longevity.As technology advances,VADs are expected to offer heart failure patients with a greater range of treatment options and a higher quality of life.

Objective:To evaluate the value of noninvasive assessment of the 13C-methacetin breath test (13C-MBT) based on infrared isotope spectrometry for liver function reserve in patients with nonalcoholic fatty liver disease (NAFLD). Methods:A total of 120 NAFLD patients met the diagnostic criteria,who admitted to Department of Liver Diseases of the First Affiliated Hospital of Xinjiang Medical University from January 2023 to January 2024,were prospectively selected. Patients were divided into three groups based on liver stiffness measurement (LSM) of FibroTouch:mild fibrosis group (LSM<7.0 kPa,n=40),moderate fibrosis group (7.0≤LSM<9.5 kPa) and severe fibrosis group (LSM≥9.5 kPa,n=40). Meanwhile,40 healthy subjects were selected as a healthy control group. All subjects underwent 13C-MBT and conventional liver function tests. The differences of 13C-MBT parameters and liver function indicators among various groups were compared,and the correlations between 13C-MBT parameters and the degree of liver fibrosis,and between liver function indexes and the degree of liver fibrosis were analyzed. Receiver operating characteristic (ROC) curve was used to evaluate the judgment ability of 13C-MBT parameters to the degree of liver fibrosis. Results:The 13C-MBT parameters in NAFLD patients were lower than those in healthy control group,and the differences were statistically significant (F=27.413,28.635,29.851,P<0.05). With the aggravation of liver fibrosis,13C-MBT parameters in NAFLD patients gradually decreased. The 13C-MBT parameters of severe fibrosis group were significantly lower than those in the mild and moderate fibrosis groups,with statistically significant differences (t=12.331,13.020,14.232,22.033,21.032,29.332,P<0.05),respectively. The 13C-MBT parameters were positively correlated with liver function indicators,and were negatively correlated with LSM,and the absolute values of the correlation coefficients were>0.5,all of them showed statistically significant differences (r=0.375,-0.875,P<0.05). The 13C-MBT parameters had higher sensitivity and specificity in judging the degree of liver fibrosis. Taking MVmax40 as an example,when the limit value was 9.5 kPa,the sensitivity was 86.3％,and the specificity was 83.8％,and the accuracy was 85.0％,and the area under curve (AUC) was 0.913. Conclusion:13C-MBT based on infrared isotope spectrometry is a non-invasive,safe,rapid and accurate detection method,which can reflect the liver function reserve and liver fibrosis degree of NAFLD patients,and has important clinical value for the diagnosis and treatment of NAFLD.

The working principle of Bausch&Lomb BL11110 phacoemulsification system was described.Three cases of typical faults of the phacoemulsification system were introduced,and the causes were analyzed,then the maintenance measures were given accordingly.References were provided for diagnosing and eliminating the faults of the phacoemulsification system.[Chinese Medical Equipment Journal,2025,46(4):118-120]

Objective:To clarify the safety, repair rate, durability, and risk factors for recurrent mitral regurgitation(MR) in patients with Barlow disease(BD) who total thoracoscopic minimally invasive mitral valvuloplasty(TMVP).Methods:Clinical data, mid-term and long-term outcomes of BD patients who underwent TMVP at Guangdong Provincial People's Hospital from January 2009 to June 2022 were retrospectively analyzed. Patients were divided into a group with no MR recurrence(group A) and a group with MR recurrence(group B) according to whether recurrent MR appeared in the postoperative period, and the data of the two groups of patients were compared with each other for the risk factor analysis.Results:The repair rate of TMVP was 98.4%, and no patient died perioperatively. The median follow-up time was 3.1(1.7, 5.2) years, the follow-up rate was 95.8%, and there was no patient died. As of March 2023, 112 patients developed no recurrent MR(group A), 11 patients developed recurrent MR(group B), and 2 patients in group B underwent repeated mitral valve surgery. The left atrial diameter(LAD) and left ventricular end-systolic diameter(LVESD) were higher in group B than in group A patients[LAD: (50.9±7.7)mm vs.(43.7±8.7)mm, P=0.009; LVESD: (37.1±5.5)mm vs.(33.2±4.7)mm, P=0.011], and the percentage of tendon cord rupture was higher in group B than in group A( P=0.022), while the rest of the baseline data were not statistically significant. There was no statistically significant difference between two groups in terms of the use of different surgical techniques, aortic cross-clamp time, cardiopulmonary bypass time, and operative time. Postoperative LAD, postoperative LVESD, and postoperative left ventricular end-diastolic diameter of group B patients were higher than those of group A( P<0.05). There was no statistically significant difference in perioperative and long-term complication rates between the two groups. Multifactorial Cox regression analysis revealed that advanced age( HR=1.049, 95% CI: 0.997-1.103, P=0.066) and large preoperative LVESD( HR=1.168, 95% CI: 1.053-1.295, P=0.003) were the risk factors for postoperative recurrence MR. Conclusion:Total thoracoscopic minimally invasive BD repair is safe, which has a high success rate and good long-term results. Advanced age and large preoperative LVESD are risk factors for recurrent MR in the long term.

Objective:To systematically evaluate the clinical efficacy and safety of Tonifying kidney and activating blood thera-py for the treatment of diabetic mellitus erectile dysfunction.Methods:China National Knowledge Infrastructure(CNKI),Wanfang Data,VIP,Chinese Biomedical Database(CBM),PubMed,Cochrane Library,Embase and Web of Science were searched from incep-tion until October 20th of 2024,for randomized controlled trials of Tonifying kidney and activating blood therapy for the treatment of dia-betic erectile dysfunction.Literature screening,quality evaluation,and data extraction were carried out in accordance with relevant standards.The software of RevMan5.4 was used for the analysis of publication bias.And meta-analysis was conducted to assess the im-pact of this therapy on IIEF-5,total effective rate,adverse reactions.The evidence levels according to the analysis results were evalua-ted.Results:Totally 19 RCTs were included,involving 1 612 patients.The result of meta-analysis indicated that Tonifying kidney and activating blood therapy had advantages on the improvement of IIEF-5 scores(MD=3.59,95％CI[2.14,5.03],P＜0.01),total effective rate(OR=4.30,95％CI[3.29,5.32],P＜0.000 01).However,there was no statistically significant difference in the inci-dence of adverse reactions(OR=0.98,95％CI[0.48,2.01],P=0.96)between the two groups.Conclusions:Tonifying kidney and activating blood therapy can improve the clinical efficacy and IIEF-5 score for the patients with diabetic erectile dysfunction.But considering the limited quantity of included studies,more high-quality studies still be needed to validate the therapeutic effect.