As an important strategy in antiviral drug development, nucleoside analogs (NAs) have attracted considerable attention due to their unique mechanisms of action and favorable safety profile. This review systematically summarizes recent advances in the mechanisms of action of NAs, focusing on the following four aspects: (1) Targeting viral polymerases, inhibiting viral replication through mechanisms such as non-absolute termination, delayed chain termination and induction of viral RNA mutations in addition to classical chain termination, which has been newly discovered; (2) Regulating RNA methylation modifications—for instance, competitively inhibiting methyltransferases, which significantly reduces viral replication efficiency; (3) Depleting nucleotide pools—by affecting host cell purine nucleotide synthesis pathways, thereby indirectly inhibiting viral replication; and (4) Immunomodulatory functions—including activation of the STING pathway to promote interferon production. Furthermore, this review systematically discusses the breakthrough progress in prodrug technologies for addressing key clinical challenges such as drug resistance and off-target toxicity of NAs. These advances provide crucial technical support for the clinical translation of NAs. These advances provide key technical support for the clinical translation of NAs. This review clarifies the multi-target action rules of NAs and provides a theoretical framework for the design of next-generation broad-spectrum antiviral agents.

Objective:To conduct enrichment and biological behavior studies on CD44 + CD24 - triple-negative breast cancer (TNBC) stem-like cells, and to construct 68Ga-labeled CD44 peptide ( 68Ga-1, 4, 7-triazacyclononane-1, 4, 7-triacetic acid (NOTA)-CD44p) and evaluate its targeting ability towards the surface marker CD44 of TNBC stem-like cells. Methods:Suspension sphere culture method was utilized to enrich and cultivate CD44 + CD24 - cell subpopulations from TNBC cell line MDA-MB-231 and non-TNBC cell line MCF-7. Flow cytometry was used to detect the expression of stem cell markers of different groups, cell scratch assay was performed to assess the migration ability of CD44 + CD24 - cell subpopulations, and Transwell invasion assay was performed to evaluate the invasion ability of CD44 + CD24 - cell subpopulations. 68Ga-NOTA-CD44p was prepared, followed by purification and identification with high-performance liquid chromatography (HPLC). The targeting ability of 68Ga-NOTA-CD44p towards CD44 + TNBC cells was evaluated through cellular uptake and blocking experiments. Data were analyzed by independent-sample t test, one-way analysis of variance and the least significant difference t test. Results:Suspension sphere culture successfully enriched CD44 + CD24 - TNBC stem-like cell spheres. Compared to the non-TNBC cell line MCF-7, TNBC cell line MDA-MB-231 exhibited better sphere-forming ability (18.50±3.73 vs 31.83±4.92; t=5.29, P<0.001) and a higher proportion of CD44 + CD24 - cell subset ((24.97±8.12)% vs (90.93±4.46)%; F=170.10, t=14.93, both P<0.001). The wound healing rate ((71.00±11.00)% vs (28.33±4.16)%; F=42.91, t=8.02, both P<0.001) and invasion rate ((60.60±16.87)% vs (24.16±8.15)%; F=11.83, t=4.40, both P<0.01) of CD44 + CD24 - MDA-MB-231 group cells were significantly increased compared to the CD44 + CD24 - MCF-7 group. MDA-MB-231 cells showed strong uptake ability of 68Ga-NOTA-CD44p, which decreased after CD44p blocking. Conclusions:Compared to CD44 + CD24 - MCF-7 cells, CD44 + CD24 - MDA-MB-231 cells exhibit higher malignant biological behavior. 68Ga-NOTA-CD44p targets the surface marker CD44 of TNBC stem-like cells, laying the research foundation for targeted therapy against TNBC with tumor stem cells as targets.

Objective To study the level of fall-related self-awareness among the elderly in community and to explore the influence of cognitive reserve and social cohesion on fall-related self-awareness,thereby providing a reference for developing targeted interventions.Methods Toally 500 old people in communities were recruited by convenience sampling in Hengyang between August and September 2024.Data were collected with the general information questionnaire,neighbourhood cohesion scale,self-awareness of falls in elderly scale,and cognitive reserve index questionnaire.Hierarchical multiple linear regression analysis was employed to explore the effects of cognitive reserve and social cohesion on fall-related self-awareness while controlling for demographic variables.Results A total of 467 valid questionnaires were returned.The score of fall-related self-awareness was 54.60±6.64(moderate level).Social cohesion scores was 29.84±5.52(moderate level),and cognitive reserve score was 93.27±10.83(moderate level).The cognitive reserve and social cohesion were both positively correlated with fall-related self-awareness(all P<0.01).Community integration accounted for 9.10%of its total variability,and cognitive reserve accounted for 5.70%of the total variability of fall vigilance,while controlling for variables such as body mass index(BMI),sleep quality,sedentary habits,fear of falling and financial resources.Conclusion The elderly in communities exhibit a low level of fall-related self-awareness.More attention to risk of falling is required along with developing targeted and individualised training programs aiming at improvement of cognitive reserve and social cohesion,thereby reducing the incidence of falls.

Objective:To analyze the current situation of medical consumables management policy in China,and to provide a reference for the refined management of medical consumables.Methods:Through the policy triangle model and policy tool theory,it comprehensively analyzes the reimbursement medical consumables catalogue and payment management policy of medical insurance in China,covering the policy background,content,process,and participant dimensions.Results:The use frequency of medical consumables policy tools is not balanced,the payment management rules need to be refined,and the participation of multi-stakeholders such as patients is lacking.Conclusion:It is necessary to further strengthen the foundational management of reimbursement medical consumables catalogue,improve the access mechanism of medical consumables for medical insurance,and explore the formulation of categorized payment standards and innovative payment mechanisms.

Objective:To investigate the current situation and correlation between mental health and stressors of new professional master's degree graduates in clinical medicine, and to provide empirical support for improving student mental health.Methods:An online questionnaire survey was conducted among 3 587 fresh graduate students with master's degree in clinical medicine from 65 training institutions in China. SPSS 26.0 was used to compare and analyze the measurement data. Descriptive statistics were used to analyze the mental health using Symptom Checklist-90 (SCL-90) and the current status of stressors. The influence factors and correlation between mental health and stressors were analyzed by means of differentiation analysis and correlation analysis.Results:The SCL-90 overall mean score as well as the scores of obsessive-compulsive symptoms, interpersonal sensitivity, depression, terror, anxious, psychoticism, and hostility of new professional master's degree graduates in clinical medicine were all higher than the national norm ( P<0.05). Among the participants, 58.21% (2 088/3 587) exhibited varying degrees of symptoms listed in the SCL-90. Students from families with low per capita income and low parental education level have more prominent psychological problems. The top three stressors perceived were job seeking, research tasks, and self-ability. Students with positive SCL-90 symptoms reported significantly higher perceived stress in all three stressor dimensions compared to their symptom-negative counterparts ( P<0.001), indicating a significant correlation between mental health status and stressors. Conclusions:The mental health status of new professional master's degree graduates in clinical medicine is concerning and warrants focused attention from educational authorities, academic institutions, and families.

Objective:To understand the graduation destination of newly graduated medical master's students in China and analyze their employment status.Methods:A questionnaire survey was conducted on 15 942 medical master's students who graduated in 2023. Descriptive analysis, χ2 test, and Kruskal-Wallis rank-sum test were used to understand the current situation and differences in the graduation destinations, employment units, job positions, and starting salaries of different types of medical master's graduates. Results:The employment rate of medical master's graduates was 58.21% (9 280/15 942). In terms of graduation destinations, male graduates, professional degree holders, graduates from non-"Double First-Class" universities, and nursing majors had a high proportion of confirmed employment units. Male graduates, academic degree holders, graduates from "Double First-Class" universities, and basic medical science majors had a high proportion pursuing further studies domestically. In terms of employment, the highest proportion of medical master's graduates worked in hospitals (84.92%, 6 495/7 648) and the lowest proportion worked in primary-level medical and healthcare institutions (1.02%, 78/7 648). The majority (78.07%, 5 971/7 648) held professional technical positions. Starting salaries were relatively low and ranged between 3 001 and 5 000 yuan/month, accounting for 30.99% (2 370/7 648).Conclusions:The employment rate of medical master's graduates is low, with concentrated employment units and job positions, and there is a lack of talents in primary medical institutions. Colleges and universities and education management departments should adopt policy-driven approaches to support key demographic groups and encourage employment in primary healthcare. Training programs should be timely adjusted in response to market demands and focus on cultivating the comprehensive quality and job competence of medical master's graduates. Additionally, student-centered approaches should be used to strengthen the employment guidance and career planning services.

Objective To study the level of fall-related self-awareness among the elderly in community and to explore the influence of cognitive reserve and social cohesion on fall-related self-awareness,thereby providing a reference for developing targeted interventions.Methods Toally 500 old people in communities were recruited by convenience sampling in Hengyang between August and September 2024.Data were collected with the general information questionnaire,neighbourhood cohesion scale,self-awareness of falls in elderly scale,and cognitive reserve index questionnaire.Hierarchical multiple linear regression analysis was employed to explore the effects of cognitive reserve and social cohesion on fall-related self-awareness while controlling for demographic variables.Results A total of 467 valid questionnaires were returned.The score of fall-related self-awareness was 54.60±6.64(moderate level).Social cohesion scores was 29.84±5.52(moderate level),and cognitive reserve score was 93.27±10.83(moderate level).The cognitive reserve and social cohesion were both positively correlated with fall-related self-awareness(all P<0.01).Community integration accounted for 9.10%of its total variability,and cognitive reserve accounted for 5.70%of the total variability of fall vigilance,while controlling for variables such as body mass index(BMI),sleep quality,sedentary habits,fear of falling and financial resources.Conclusion The elderly in communities exhibit a low level of fall-related self-awareness.More attention to risk of falling is required along with developing targeted and individualised training programs aiming at improvement of cognitive reserve and social cohesion,thereby reducing the incidence of falls.

Objective:To investigate the current situation and correlation between mental health and stressors of new professional master's degree graduates in clinical medicine, and to provide empirical support for improving student mental health.Methods:An online questionnaire survey was conducted among 3 587 fresh graduate students with master's degree in clinical medicine from 65 training institutions in China. SPSS 26.0 was used to compare and analyze the measurement data. Descriptive statistics were used to analyze the mental health using Symptom Checklist-90 (SCL-90) and the current status of stressors. The influence factors and correlation between mental health and stressors were analyzed by means of differentiation analysis and correlation analysis.Results:The SCL-90 overall mean score as well as the scores of obsessive-compulsive symptoms, interpersonal sensitivity, depression, terror, anxious, psychoticism, and hostility of new professional master's degree graduates in clinical medicine were all higher than the national norm ( P<0.05). Among the participants, 58.21% (2 088/3 587) exhibited varying degrees of symptoms listed in the SCL-90. Students from families with low per capita income and low parental education level have more prominent psychological problems. The top three stressors perceived were job seeking, research tasks, and self-ability. Students with positive SCL-90 symptoms reported significantly higher perceived stress in all three stressor dimensions compared to their symptom-negative counterparts ( P<0.001), indicating a significant correlation between mental health status and stressors. Conclusions:The mental health status of new professional master's degree graduates in clinical medicine is concerning and warrants focused attention from educational authorities, academic institutions, and families.

Objective:To understand the graduation destination of newly graduated medical master's students in China and analyze their employment status.Methods:A questionnaire survey was conducted on 15 942 medical master's students who graduated in 2023. Descriptive analysis, χ2 test, and Kruskal-Wallis rank-sum test were used to understand the current situation and differences in the graduation destinations, employment units, job positions, and starting salaries of different types of medical master's graduates. Results:The employment rate of medical master's graduates was 58.21% (9 280/15 942). In terms of graduation destinations, male graduates, professional degree holders, graduates from non-"Double First-Class" universities, and nursing majors had a high proportion of confirmed employment units. Male graduates, academic degree holders, graduates from "Double First-Class" universities, and basic medical science majors had a high proportion pursuing further studies domestically. In terms of employment, the highest proportion of medical master's graduates worked in hospitals (84.92%, 6 495/7 648) and the lowest proportion worked in primary-level medical and healthcare institutions (1.02%, 78/7 648). The majority (78.07%, 5 971/7 648) held professional technical positions. Starting salaries were relatively low and ranged between 3 001 and 5 000 yuan/month, accounting for 30.99% (2 370/7 648).Conclusions:The employment rate of medical master's graduates is low, with concentrated employment units and job positions, and there is a lack of talents in primary medical institutions. Colleges and universities and education management departments should adopt policy-driven approaches to support key demographic groups and encourage employment in primary healthcare. Training programs should be timely adjusted in response to market demands and focus on cultivating the comprehensive quality and job competence of medical master's graduates. Additionally, student-centered approaches should be used to strengthen the employment guidance and career planning services.

Objective:To analyze the current situation of medical consumables management policy in China,and to provide a reference for the refined management of medical consumables.Methods:Through the policy triangle model and policy tool theory,it comprehensively analyzes the reimbursement medical consumables catalogue and payment management policy of medical insurance in China,covering the policy background,content,process,and participant dimensions.Results:The use frequency of medical consumables policy tools is not balanced,the payment management rules need to be refined,and the participation of multi-stakeholders such as patients is lacking.Conclusion:It is necessary to further strengthen the foundational management of reimbursement medical consumables catalogue,improve the access mechanism of medical consumables for medical insurance,and explore the formulation of categorized payment standards and innovative payment mechanisms.