From visual teaching aids,experiment phenomenon,imagination,clinical cases and the aspects such as daily life phenomenon and computer supplementary teaching,this article has discussed the application of“Image-thinking” in biochemistry teaching,and from the angle of medical educational reform,it has also discussed the importance of its raising the teaching effect.

OBJECTIVE:To study the apoptosis of human leukemic cells induced by Dihydroartemisinin and its molecular mechanism.METHODS:Human leukemia K562 cells were treated by Dihydroartemisinin.The inhibitory effect on cell proliferation was assayed by MTT.Fluorescence microscopy was applied to observe the presence of apoptosis.The expression of caspase-3 was assayed with reverse transcription-polymerase chain reaction(RT-PCR).Levels of mitochondrial and cytoplasmic cytochrome C were determined using Western blot.RESULTS:After treatment with Dihydroartemisinin for 48 hours,the IC50 values of human leukemia K562 cells were 8? 10-5mol? L-1 detected at a wavelength of 570nm by MTT.Distinct morphology changes of cell apoptosis such as karyopyknosis and conglomeration were observed by Hoechst33342/PI staining.RT-PCR assay showed the expression of Caspase-3.Western-blot detection showed the decrease of mitochondrial cytochrome C concentration but the positive expression of cytoplasmic cytochrome C concentration.CONCLUSION:Dihydroartemisinin could inhibit proliferation and induce apoptosis of human leakemic K562 cells,this may partially attributed to the promotion of the delivery of cyt-c and the activation of caspase-3.

Objective: To investigated the effect of long-term low-concentration mixed benzene exposure on peripheral blood of male workers. Methods: A case-control study was conducted to select 452 male workers exposed to mixed benzene (benzene, toluene, xylene) for five consecutive years from January 2012 to December 2016 in an automobile manufacturer as case group, and 438 male administrative and logistic managers who underwent physical examination during the same period as control group. The peripheral blood of the two groups was tested and compared, and the occupational hazards in the workplace were detected. Results: There were low dose exposure to mixed benzene in the enterprise, but the test results met the occupational exposure limit requirements. During the five years from 2010 to 2016, between the two groups of workers, the mean values of WBC, NEUT, RBC and Hb were statistically different (P<0.05). There was no statistical difference (P>0.05) in the mean value of PLT. The abnormal rate of main peripheral blood indexes in the control group was higher than that in the exposed group. There were significant differences in NEUT, RBC and Hb (P< 0.05), but no significant differences in WBC and PLT (P>0.05). Conclusion It can not be concluded that long-term low-concentration mixed benzene exposure can cause the change of peripheral blood index.

Objective:To investigate the effect of early gradual diet on reducing delirium in elderly patients with hip arthroplasty.Methods:From January 2018 to January 2020, 74 cases of hip arthroplasty patients aged over 65 years old who were treated in the Third Affiliated Hospital of Sun Yat-sen University were selected as the observation objects. They were randomly divided into experimental group and control group with 37 cases in each group. The experimental group was given early gradual diet on the basis of routine postoperative care, while the control group was given routine postoperative diet on the basis of routine postoperative care. The incidence of postoperative delirium, Pittsburgh Sleep Quality Index (PSQI), patient satisfaction rate, average hospitalization days and average hospitalization expenses were used to evaluate the effect of early gradual diet on reducing delirium in elderly patients with hip arthroplasty.Results:The incidence of delirium in the experimental group was 2.70% (1/37) and 16.22% (6/37) in the control group, the difference was statistically significant ( χ2 value was 3.945, P<0.05); the hospitalization days of the experimental group were (10.68±5.13) d, (13.62±7.19) d in the control group. The difference of hospitalization days was statistically significant ( t value was 2.877, P<0.01). The incidence of difficulty in falling asleep and the satisfaction rate of the experimental group were 8.11% (3/37) and 94.59% (35/37) respectively, and those in the control group were 29.73% (11/37) and 78.38% (29/37) respectively, and the differences were statistically significant ( χ2 value was 5.638, 4.163, P<0.05). Conclusions:Early gradual diet after operation can reduce the incidence of delirium in elderly patients with hip arthroplasty, shorten the average hospitalization days, reduce the incidence of difficulty in falling asleep, improve patients' satisfaction, and help patients to pass through the perioperative period more safely and comfortably.

Objective: To understand the prevalence of gynecologic diseases among married female workers. Methods: The data of married female workers who underwent occupational health examination in a physical examination center from January to December 2017 were collected. The relationship between the detection of common gynecological diseases, age and occupational types examined by gynecological routine, TCT, breast B-mode ultrasound, uterus and appendix B-mode ultrasound were analyzed. Results: Among the 1142 female workers, the total detection rate of reproductive tract infections was 67.25% (768/1142), the total detection rate of breast-related diseases was 75.22% (859/1142) ; the total detection rate of gynecological tumors and benign lesions was 14.71% (168/1142). The detection rate of breast hyperplasia was the highest 67.08% (766/1142), followed by vaginitis 51.66% (590/1142). Among the abnormalities detected in breast-related diseases, gynecological tumors and benign lesions, the highest detection rate was found in public institutions (85.66% and 27.13%), and the lowest was found in factory workers (70.24% and 7.89%). With the increase of age, the detection rate of breastrelated diseases (breast hyperplasia, breast cyst), gynecological tumors, benign lesions (uterine myoma), and Nessler's cyst abnormalities in married female workers increased (χ²_trend=7.647、21.653、107.411、53.802, P<0.05), while the detection rate of columnar epithelium of cervix decreased (χ²_trend=7.404, P<0.05). There was no significant difference in the total detection rate of reproductive tract infectious diseases (vaginitis, cervical polyps, cervical hypertrophy) among married famale workers of different ages (P<0.05) . Conclusion The common gynecological diseases of married female workers are affected by many factors such as age and occupation. Health examination and health education should be carried out regularly to reduce the incidence of gynecological diseases among female workers according to different ages and occupations.

BackgroundGraduate students frequently face life events， many of which may adversely affect their mental well-being. However， the interaction between life events and the development of depression， anxiety， and somatic symptoms remains unclear. ObjectiveTo explore the relationship between life events and the development of depressive， anxiety and somatic symptoms in graduate students， thereby informing prevention strategies for these conditions. MethodsA sample of 6 722 newly enrolled graduate students at a comprehensive university in Southwest China from September to November 2018 was selected. The assessment was conducted using the Adolescent Self-rating Life Events Checklist （ASLEC）， the 7-item Generalized Anxiety Disorder scale-7 item （GAD-7）， the Patient Health Questionnaire Depression Scale-9 item （PHQ-9）， and the Patient Health Questionnaire-15 （PHQ-15）. Network analysis was implemented by using the bootnet and qgraph packages in the R software （version 4.2.3）， with centrality indices calculated to identify core and bridge symptoms within the network. ResultsThe study encompassed a total of 6 171 graduate students， representing 91.80% of the target population. The prevalence rates of anxiety， depressive， and somatic symptoms among graduate students were 12.59% （777/6 171）， 16.63% （1 026/6 171）， and 27.66% （1 707/6 171）， respectively. Network analysis revealed that 'academic stress' was the core symptom with the highest strength and expected influence （both values=1.207）， while 'feeling down， depressed， or hopeless' was the bridge symptom with the highest bridge strength and bridge expected influence （both values=0.454）. There was no significant difference in global network strength and edge weight between women and men （P>0.05）. ConclusionAcademic stress， emerging as the core symptom， assumes a dominant position within the symptom network and exhibits strong interactions with other negative affective states. There was no gender difference in the network structure.

BackgroundPrevious studies have identified a close relationship among psychological neglect and abuse， negative affect， different stages of adolescence， and suicidal ideation. However， the mechanisms underlying the impact of psychological abuse and neglect on suicidal ideation among left-behind adolescents remain unclear， and this field of research is still in its relative infancy. ObjectiveTo explore the relationship between psychological neglect/abuse and suicidal ideation among left-behind adolescents， as well as the mediating role of negative affect and the moderating effect of different stages of adolescence， so as to provide insights for preventing and intervening suicidal ideation in this population. MethodsFrom November 2021 to May 2022， a cluster random sampling technique was utilized to select 2 309 left-behind adolescents in western China. Assessments were conducted using the Child Psychological Abuse and Neglect Scale （CPANS）， the Positive and Negative Suicide Ideation （PANSI） and the Positive and Negative Affect Schedule for Children （PANAS-C）. Spearman correlation coefficients were calculated across all samples， and Process 4.1 was employed to test the mediating role of negative affect and the moderating role of different stages of adolescence in the pathway linking psychological abuse/neglect to suicidal ideation. ResultsA total of 2 119 left-behind adolescents （mean age： 14.94±1.20 years） completed the study， with males comprising 51.34% （1 088/2 119） and females 48.66% （1 031/2 119）.Among left-behind adolescents， scores on CPANS psychological neglect subscale showed positive correlations with both psychological abuse subscale scores and PANAS-C negative affect subscale scores （r=0.446， 0.496， P<0.01）. Additionally， CPANS psychological neglect and psychological abuse subscale scores were also positively correlated with PANSI scores （r=0.487， 0.508， P<0.01）. Furthermore， PANAS-C negative affect subscale scores demonstrated a positive correlation with PANSI scores （r=0.499， P<0.01）. Negative affect partially mediated the relationship between psychological abuse/psychological neglect and suicidal ideation， with effect sizes of 0.166 （95% CI： 0.141~0.191） and 0.131 （95% CI： 0.112~0.152）. Different stages of adolescence moderated the latter part （negative emotion → suicidal ideation） of the indirect mediation path from psychological neglect to suicidal ideation through negative affect （β=-0.066， P<0.01）. ConclusionBoth psychological neglect and psychological abuse may influence suicidal ideation among left-behind adolescents via negative affect. Moreover， different stages of adolescence may moderate the indirect path from psychological neglect to suicide ideation through negative affect.