ObjectiveTo explore the effects of Jingui Shenqiwan （JSW） and Liuwei Dihuangwan （LDW） on the reproductive ability and brain function of normal mice and compare the actions of the two medications. MethodsSeven groups of female and male mice were divided at a ratio of 2∶1. Except for the control group， the other six groups were as follows： a group of both males and females receiving JSW （3.0 g·kg^-1）， a group of both males and females receiving LDW （4.5 g·kg^-1）， a group of males receiving water and females receiving JSW， a group of males receiving water while females receiving LDW， a group of females receiving water while males receiving JSW， and a group of females receiving water while males receiving LDW. Each group was administered the drug for 14 days and then caged together at a 2∶1 （female∶male） ratio to detect the number of pregnant mice and calculate the pregnancy rate. Pregnant mice continued receiving the drug until they naturally gave birth， which was followed by the observation of newborn mice， calculation of their average number， and the measurement of the offspring's preference for sugar water and neonatal recognition index. At the end of the experiment， the weights of the thymus and spleen were measured to calculate the organ coefficients， and mRNA or protein expression was analyzed in the brain and testes or ovaries. A 1% sucrose solution was used to examine the euphoria of their brain reward systems， while novel object recognition test （NOR） was applied to assess their memory capabilities. mRNA expression was detected using real-time quantitative polymerase chain reaction （Real-time PCR） assay， and protein expression was analyzed with Western blot. ResultsCompared with the control group， oral administration of JSW to both male and female mice for 14 days significantly increased the pregnancy rate of female mice on day 2 after being caged together （P<0.05）， while LDW showed a trend but no statistical significance. Additionally， compared with the control group， JSW could upregulate the gene expression of gonadotropin-releasing hormone （GnRH） in the thalamus， as well as reproductive stem cell factor （SCF） and tyrosine kinase receptor （c-Kit） in the testes and reproductive stem cell marker mouse vasa homologue （MVH） in the ovaries， upregulate the expression of proteins influencing neuronal functional activity， such as brain-derived neurotrophic factor （BDNF）， in hippocampal neurons （P<0.05）， and enhance sucrose preference in male mice （P<0.05）. Compared with the control group， JSW significantly increased sucrose preference and novel object recognition index in offspring mice （P<0.05）， which was related to the upregulation of hippocampal dopamine D1 receptor （D1R） and N-methyl-D-aspartate receptor （Nmdar） gene expression. Compared with the control group， both JSW and LDW could upregulate the protein expression of glucocorticoid receptor （GR）， BDNF， and tyrosine kinase receptor B （TrkB） in the hippocampus of offspring mice （P<0.05）. ConclusionJSW significantly enhances the reproductive ability of normal mice， which is not only related to the release of gonadotropin but also associated with its regulation of brain function. Additionally， JSW has a certain regulatory effect on the brain function of the offspring mice.

ObjectiveThis study aims to explore the mechanism by which Yishen Huoxue Tongqiao Formula improves metabolism-neuroplasticity and treats unilateral vestibular labyrinth destruction by regulating the metabolic balance of glutamate （Glu）/γ-aminobutyric acid （GABA）. Methods48 Sprague-Dawley （SD） adult rats were randomly divided into the sham operation group， model group， Yishen Huoxue Tongqiao Formula groups with low， medium， and high doses （9.20， 18.39， 36.78 g·kg^-1）， and betahistine group （1.62 mg·kg^-1）. A unilateral vestibular labyrinth destruction （vestibular dysfunction） model was established by intratympanic injection of chloroform into the right ear， while the control group received intratympanic injection of normal saline. Drugs were administered once daily for seven consecutive days. During the period， behavioral tests were performed to evaluate the behaviors of rats after unilateral vestibular labyrinth destruction. Hematoxylin-eosin （HE） staining and Nissl staining were used to observe the neuronal morphology in the medial vestibular nucleus. Golgi staining was employed to assess the number of dendritic spines of neurons in the medial vestibular nucleus. Ultra-performance liquid chromatography-tandem mass spectrometry （LC-ESI-MS/MS） was utilized to detect Glu/GABA. Immunofluorescence and immunohistochemistry were used to detect the expressions of neuronal nuclei （NeuN）， growth-associated protein 43 （GAP-43）， and glial fibrillary acidic protein （GFAP）. Western blot and real-time fluorescent quantitative polymerase chain reaction （Real-time PCR） were applied to determine the expressions of glutamate-immunoreactive （Glu-IR）， GABA， GFAP， postsynaptic density protein 95 （PSD-95）， and GAP-43. ResultsCompared with the sham operation group， the model group presented with head deviation， balance disorder， increased tail suspension score， nuclear consolidation of medial vestibular nerve neurons， and decreased Nissl bodies （P<0.01）. The number of dendritic spines in neurons and NeuN-positive cells decreased. The content of Glu decreased. The content of GABA increased （Glu/GABA decreased）. The expression of GAP-43 was down-regulated， and GFAP was up-regulated （P<0.05， P<0.01）. The expressions of Glu-IR， PSD-95， and GAP-43 proteins， as well as Glu-IR mRNA decreased， while the expressions of GABA and GFAP proteins and mRNA increased （P<0.05， P<0.01）. Compared with those in the model group， the head deviation， imbalanced behavior， and tail suspension scores in each treatment group decreased， with alleviated neuronal injury and recovered Nissl bodies （P<0.01）. The number of dendritic spines of neurons increased， and the number of NeuN-positive cells rebounded. The content of Glu increased， and the content of GABA decreased （Glu/GABA increased）. GFAP was down-regulated， and GAP-43 was up-regulated （P<0.05， P<0.01）. The expressions of Glu-IR， PMD-95， and GAP-43 proteins， as well as Glu-IR mRNA increased， while the expressions of GABA and GFAP proteins and mRNA decreased. The effect was more significant in the high-dose group （P<0.01）. ConclusionThe Yishen Huoxue Tongqiao Formula can alleviate vestibular dysfunction， and its mechanism may be associated with regulating the metabolic balance of Glu/GABA， mitigating neural damage， improving synaptic plasticity （promoting GAP-43 expression and inhibiting GFAP expression）， and facilitating vestibular compensation.

Objective: To characterize perioperative dynamic changes in immune-cell phenotypes and inflammatory cytokines in patients undergoing CPB (cardiopulmonary bypass) cardiac surgery, and to explore their associations with postoperative outcomes. Methods: In this prospective cohort study, 120 adult patients who underwent elective cardiac surgery under CPB at West China Hospital from May 2022 to March 2023 were enrolled. Perioperative immune-cell phenotypes and concentrations of 40 inflammation-related cytokines were measured. The primary outcomes were the sequential organ failure assessment (SOFA) score at 24 h after surgery and ΔSOFA (the peak SOFA score within 48 h after surgery minus the preoperative SOFA score). Secondary outcomes included major adverse cardiovascular events (MACE), acute kidney injury (AKI), respiratory failure, severe liver injury, and infection. Results: The mean age of enrolled patients was 57±10 years. Of these, 52% (62/120) were male and 90% (108/120) underwent valve surgery. During the rewarming to the end of CPB, neutrophil counts rapidly increased (7.39×10 /L vs preoperative 3.07×10 /L, P<0.001), with significant upregulation of CD11b (7.30×10 /L vs preoperative 3.05×10 /L, P<0.001) and CD54 (7.15×10 /L vs preoperative 2.99×10 /L, P<0.001). Lymphocyte counts increased at the end of CPB (1.75×10 /L vs preoperative 1.12×10 /L, P<0.001) but decreased significantly at 24 h after surgery (0.59×10 /L vs preoperative 1.12×10 /L, P<0.001). Plasma analysis showed that multiple pro-inflammatory cytokines increased during CPB and remained elevated up to 24 h after surgery; five chemokines and the anti-inflammatory cytokine IL-10 peaked at the end of CPB. The SOFA score increased from 1 (1, 2) preoperatively to 7 (5, 10) at 24 h after surgery, with a ΔSOFA of 6 (4, 8). Within 30 days after surgery, 48 patients (40.0%) developed AKI, 17 (14.2%) developed infection, 4 (3.3%) developed severe liver injury, 3 (2.5%) developed respiratory failure, and 3 (2.5%) experienced MACE. During the 2-year follow-up, 8 patients (6.7%) experienced MACE and 5 (4.2%) died. Conclusion: Multi-organ dysfunction is common after cardiac surgery under CPB (median ΔSOFA, 6), accompanied by perioperative activation of multiple immune-cell subsets and upregulation of pro-inflammatory, anti-inflammatory, and chemotactic mediators. This study provides data-driven evidence and research clues for further investigation of the associations between CPB-related immune perturbations and postoperative organ dysfunction and clinical outcomes.

ObjectiveTo explore the effect of Shenge Bushen Capsules （SBC） on sexual development in normal 3-week-old mice. MethodsThe experiment consisted of two parts. In the first part， mice were divided into four groups： The control group and the low， medium， and high-dose SBC groups （234.7， 469.4， 938.7 mg·kg^-1， respectively）. In the second part， mice were divided into four groups： Control group， Pseudostellariae Radix polysaccharide （PRP） group， total flavonoids group， and SBC group， all receiving a dose of 469.4 mg·kg^-1. After 7 days of administration， the vaginal opening of female mice and the descent of testes and scrotum in male mice， as well as the ovarian and testicular organ indices， were observed. After 4 weeks of administration， female and male mice were housed together for 2 days， and the pregnancy rate of females was monitored. After delivery， the pregnant female mice continued receiving the treatment for 4 weeks， and the sexual development of their offspring， including vaginal opening， testicular descent， and organ indices of ovaries and testes， was observed. Serum sex hormones were measured by enzyme-linked immunosorbent assay （ELISA）， and the expression of gonadotropin-releasing hormone （GnRH） and growth hormone （GH） proteins in the hypothalamus was assessed by Western blot. ResultsCompared with the control group， there was no significant effect on the vaginal opening of female mice or the descent of testes in male mice after 7 days of SBC administration. After 4 weeks of administration， the pregnancy rate in the low-dose group was significantly reduced （P<0.05）， but no significant effects were observed in the other groups. The three doses of SBC did not significantly affect the ovarian or testicular organ indices， and there was no significant upregulation in the expression of GnRH or GH in the hypothalamus. The primary component of SBC， Pseudostellariae Radix polysaccharide， significantly reduced the vaginal opening in female mice after 7 days of administration （P<0.05）. After 4 weeks， the serum estradiol levels of non-pregnant female mice were decreased （P<0.05）， but there was no significant effect on the expression of GnRH or GH proteins in the hypothalamus of either male or female mice. Additionally， there were no significant effects on precocious puberty indicators， such as vaginal opening and testicular descent， in the offspring mice. ConclusionSBC does not significantly promote precocious puberty in young mice， and it does not have any noticeable effects on the pregnancy rate of adult mice or the sexual development of their offspring.

ObjectiveTo investigate the effect and mechanism of cordycepin in inhibiting fat infiltration after rotator cuff injuries in rats by regulating the Wnt/β-catenin signaling pathway， providing a theoretical basis for clinical treatment of rotator cuff injuries. MethodsFifty SPF-grade female SD rats were used in this study， with 10 randomly selected as the blank group. A rotator cuff injury repair model was established by supraspinatus tendon and suprascapular nerve compression. The successfully modeled rats were randomized into model and low-dose （20 mg·kg^-1）， medium-dose （40 mg·kg^-1）， and high-dose （80 mg·kg^-1） cordycepin groups. After 6 weeks of treatment， the gait analysis was performed to assess the limb function in rats. Oil red O staining and Masson staining were employed to observe pathological changes in the muscle tissue. Enzyme-linked immunosorbent assay （ELISA） was used to measure the levels of interleukin-1β （IL-1β）， interleukin-6 （IL-6）， and tumor necrosis factor-α （TNF-α） in the serum. Immunohistochemistry （IHC） was employed to detect the expression of peroxisome proliferator-activated receptor γ （PPARγ） and CCAAT/enhancer-binding protein α （C/EBPα）， which are markers of adipogenesis. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） and Western blot were employed to determine the mRNA and protein levels， respectively， of Wnt3a， Wnt10b， and β-catenin. ResultsCompared with the blank group， the model group showed decreases in stride length and paw print area （P<0.01）， an increase in ratio of wet muscle mass reduction and a decrease in muscle fiber cross-sectional area （P<0.05）， and decreased ratios of fat infiltration area and collagen fiber area （P<0.01）. Additionally， the model group showed elevated levels of IL-1β， IL-6， and TNF-α （P<0.05）， up-regulated protein levels of PPARγ and C/EBPα （P<0.01）， and down-regulated mRNA and protein levels of Wnt3a， Wnt10b， and β-catenin （P<0.05， P<0.01）. Compared with the model group， the low-， medium-， and high-dose cordycepin groups showed increases in stride length and paw print area （P<0.01）， a decrease in ratio of wet muscle mass reduction and an increase in muscle fiber cross-sectional area （P<0.05）， and increases in ratios of fat infiltration area and collagen fiber area （P<0.05， P<0.01）. In addition， cordycepin lowered the serum levels of IL-1β， IL-6， and TNF-α （P<0.05， P<0.01）， down-regulated the protein levels of PPARγ and C/EBPα （P<0.01）， and up-regulated the mRNA and protein levels of Wnt3a， Wnt10b， and β-catenin （P<0.05， P<0.01）. ConclusionCordycepin can improve the limb function， alleviate rotator cuff muscle atrophy， fat infiltration， and fibrosis， and inhibit inflammation in rats by regulating the Wnt/β-catenin signaling pathway.

OBJECTIVE To establish the fingerprint of Pinghuo tea standard decoction and a method for determination of multi-component to clarify the transfer relationship of quantities and quality from pieces and standard decoction. METHODS Fifteen batches of Pinghuo tea standard decoction were prepared and the extract rate was determined； the fingerprint of the preparation was established by using high-performance liquid chromatography（HPLC）； the similarity evaluation and the determination of common peaks were performed， and chemometric analysis was performed； the same method was used to determine the content of indicator components and the transfer rate was calculated. The chromatographic column was Venusil C18 column with mobile phase consisted of acetonitrile-0.1% phosphoric acid solution （gradient elution）； the column temperature was 30 ℃， and the detection wavelengths were 238 nm （0-37 min， 85-102 min） and 330 nm （37-85 min） at a flow rate of 1.0 mL/min with an injection volume of 10 μL. RESULTS The similarity of HPLC fingerprints for 15 batches of Pinghuo tea standard decoction was not lower than 0.968. A total of 24 common peaks were calibrated and 9 peaks were recognized， which were as follows neochlorogenic acid （peak 3）， chlorogenic acid （peak 6）， geniposide （peak 9）， glycyrrhizin （peak 10）， galuteolin （peak 11）， isochlorogenic acid A （peak 14）， luteolin （peak 21）， kaempferol （peak 23） and glycyrrhizic acid （peak 24）. Cluster analysis， principal component analysis and orthogonal partial least squares discriminant analysis showed consistent results， all of which could classify the 15 batches of samples into three categories. The linear range of indicator components in 15 batches of Pinghuo tea standard decoction， such as geniposide， luteolin， isochlorogenic acid A， glycyrrhizin， and glycyrrhizic acid， were 0.020 580-0.411 600， 0.001 617-0.080 850， 0.006 076-0.607 600， 0.005 125-0.071 740， and 0.017 288-0.432 200 mg/mL， respectively； RSDs of precision， repeatability， stability and recovery rate tests were all not higher than 4% （n＝6）. The mass fractions ranged 3.227 9-10.002 2， 0.297 4-0.554 6， 3.350 1-6.159 6， 0.720 6-1.073 3， 2.003 1-3.030 1 mg/g； transfer rates from the pieces and standard decoction were 19.762 8%-35.840 5%， 12.123 3%-21.254 0%， 46.097 2%-82.869 4%， 58.708 8%-91.629 6%， 39.114 3%-63.710 6%. The transfer rates of the extract from 15 batches of Pinghuo tea standard decoction ranged from 61.15%-84.68%. CONCLUSIONS Established HPLC fingerprint and content determination methods in this study are simple and accurate， which can provide reference for the quantitative value transfer study， quality control， clinical application and the development of subsequent formulations of Pinghuo tea standard decoction.

It has been demonstrated that long-term space flights have a significantly greater impact on the cardiovascular, skeletal, and nervous systems of astronauts. The structural and functional alterations in the skeletal and muscular systems resulting from exposure to weightlessness can lead to the development of low back pain, significantly impairing the ability of astronauts to perform tasks and respond to emergencies. Both space flight and simulated microgravity have been shown to result in low back pain among astronauts, with the following factors identified as primary contributors to this phenomenon. The occurrence of intervertebral disc (IVD) edema results in the stimulation of type IV mechanoreceptors, which subsequently activate nociceptive afferents. The protrusion of an IVD causes compression of the spinal nerve roots. Furthermore, the elongation of the vertebral column and/or the diminished lumbar curvature of the spine exert traction on the dorsal root nerves. Paravertebral muscle degeneration leads to the inhibition of decreased nociceptive activity of the wide-dynamic range neurons of the spinal dorsal horn. Moreover, endogenous pain descending facilitation triggered by conditioning stimulation can be enhanced via the thalamic mediodorsal nuclei, while endogenous pain descending inhibition triggered by conditioning stimulation can be weakened via the thalamic ventromedial nuclei. Psychological factors may contribute to the development of low back pain. The mechanisms governing the generation, maintenance, and alleviation of low back pain in weightlessness differ from those observed in normal gravitational environments. This presents a significant challenge for space medicine research. Therefore, the elucidation of the occurrence and development mechanism of low back pain in weightlessness is important for the prevention and treatment during space flight. To reduce the incidence of low back pain during long-term missions on the space station, astronauts may choose to wear specialized space clothing that can provide axial physiological loads, designed to stimulate both musculature and skeletal structures, mitigating potential increases in vertebral column length, diminished lumbar curvature, and intervertebral disc edema and/or muscular atrophy. Additionally, assuming a “fetal tuck position” described as the knees to chest position may increase lumbar IVD hydrostatic pressure, subsequently reducing disc volume, rectifying diminished lumbar curvature, and alleviating dorsal root nerve tensions. Moreover, this position may reduce type IV mechanoreceptor facilitation and nerve impulse propagation from the sinuvertebral nerves of the annulus fibrosus. Elongated posterior soft tissues (apophyseal joint capsules and ligaments) with spinal flexion may potentially stimulate type I and II mechanoreceptors. It is also recommended to exercise the paraspinal muscles to prevent and alleviate the decrease in their cross-sectional area and maintain their structure and function. Photobiomodulation has been proved to be an effective means of activating the pain descending inhibition pathway of the central nervous system. In addition, astronauts should be encouraged to participate in mission-related activities and strive to avoid psychological problems caused by the long-term confinement in a small space station. The article presents a concise review of potential causes and targeted treatment strategies for low back pain induced by space flight or simulated microgravity in recent years. Its objective is to further elucidate the mechanisms underlying the occurrence and development of low back pain in weightless environments while providing scientific evidence to inform the development of guidelines for preventing, treating, and rehabilitating low back pain during long-term space flights.

[Objective] To investigate the seroprevalence characteristics of hepatitis E virus (HEV) among blood donors with hepatitis B virus (HBV) infection, so as to provide data support for the monitoring, prevention and treatment of HEV. [Methods] From January to December 2022, 219 samples positive for hepatitis B surface antigen (HBsAg), 142 occult hepatitis B virus infection (OBI) samples (HBV group) and 873 samples tested negative (control group) were collected. 361 samples were further tested with viral load assay and serological testing for five serological markers (HBsAg, HBsAb, HBeAg, HBeAb and HBcAb), and the DNA load was measured using real time fluorescence quantitative PCR. Commercially available enzyme-linked immunosorbent assays (ELISA) were used for the detection of anti-HEV IgG, anti-HEV IgM and HEV antigen (Ag). The Chi-square test or Fisher's exact test was used to assess the differences in the reactivity rates of anti-HEV IgG and anti-HEV IgM among different blood donor populations and different variables. Multivariable logistic regression was used to examine potential risk factors associated with anti-HEV IgG seroprevalence. [Results] In the HBV group, HBsAg positive donors exhibited low expression of antigen. The HBV DNA load of OBI infected donors ranged from 1 to 131.43 IU/mL (median 11.24 IU/mL). The prevalence of anti-HEV IgG and IgM antibody in the HBV group were 34.63% and 1.11%, respectively. Among them, the prevalence of anti-HEV IgG and anti-HEV IgM in the HBV group was 34.63% and 0, respectively (P<0.05), while in the OBI donors, they were 41.55% and 2.82%, respectively. In the normal donors, the reactivity rates for anti-HEV IgG and anti-HEV IgM were 18.67% and 1.49%, respectively. Statistical analysis showed that there was a difference in the reactivity rate of anti-HEV IgG between the HBV-infected donors and the normal donors (34.63% vs 18.67%, P<0.05), but no difference in the reactivity rate of anti-HEV IgM (1.11% vs 1.49%, P>0.05). No HEV Ag was detected in either group of blood donors. Multivariate logistic regression analysis indicated that age was an independent risk factor for anti-HEV IgG reactivity in both groups of blood donors. [Conclusion] The reactivity rate of anti-HEV IgG among HBV-infected blood donors was significantly higher than that in the normal donors in Wuhan, with age being an independent risk factor. Therefore, for HBV-infected donors, it is essential to strengthen and prioritize the prevention and treatment of HEV to reduce the spread of HEV.

OBJECTIVE To analyze the occurrence characteristics and risk factors of adverse drug reactions （ADR） of gemcitabine for injection in national centralized volume-based procurement （hereinafter referred to as “centralized procurement”）， and provide reference for clinical safe drug use. METHODS A retrospective study was conducted to collect the relevant case reports of gemcitabine for injection reported to the National Adverse Drug Reaction Monitoring System by Inner Mongolia Autonomous Region from January 2022 to December 2023； basic information of patients， drug use status， patient outcomes， rational drug use and other information were collected， and the occurrence characteristics of ADRs with leukopenia， myelosuppression， neutropenia， thrombocytopenia and liver dysfunction were analyzed. Univariate analysis and multivariate Logistic regression were used to analyze the correlation of gender， age， combination of antitumor drugs， original malignant tumor and drug dose with ADR. RESULTS A total of 315 cases reports （315 patients） of gemcitabine-induced ADR were included in this study， with a male-to-female ratio of 1.42∶1 and age of （61.17±9.13） years. The primary malignant tumor was pancreatic cancer （73 cases， 23.17%）. Leukopenia， myelosuppression and nausea were the most common ADR， followed by neutropenia， thrombocytopenia， liver dysfunction and so on. The severity grade of ADR was mainly 1-2， and the outcome of most ADR was good. Multivariate Logistic regression analysis showed that combination of antitumor drugs was a risk factor for myelosuppression and neutropenia （RR＝2.154， 95%CI： 1.218- 3.807， P＝0.008； RR＝3.099， 95%CI： 1.240-7.744， P＝0.016）； gender （female） was a risk factor for leukopenia and liver dysfunction （RR＝0.508， 95%CI： 0.302-0.853， P＝0.010； RR＝0.301， 95%CI： 0.102-0.887， P＝0.029）. In terms of drug use rationality， there were 143 cases （45.40%） of drug 126.com use in accordance with the indications of the label， and 172 cases （54.60%） of off-label drug use. Among them， the primary malignant tumors were bladder cancer， bile duct cancer and ovarian cancer， which ranked the top three off-label drug use. CONCLUSIONS The ADR caused by gemcitabine in Inner Mongolia is mainly in the blood and digestive systems. The severity of ADRs is mainly classified as 1-2 levels， and most ADRs have good outcomes. Gender （female） and combination medication are risk factors for gemcitabine-induced ADR. Appropriate chemotherapy regimen should be selected according to the patient’s condition and physical condition， and ADR monitoring in blood and digestive systems should be strengthened during medication of gemcitabine.

Objective: To investigate the changes of dentin surface and the effects of different surface treatments on the rebonding effect following non-destructive restoration removal by an Er:YAG laser and to provide reference for oral clinical operation Methods: This study was approved by the ethics review committee of the unit. Using computer-aided design and computer-aided manufacturing (CAD/CAM) technology, 102 zirconia specimens (4 mm × 4 mm × 1.5 mm) were fabricated. In total, 110 impacted third molar teeth were extracted, and 102 dentine blocks (4 mm × 4 mm × 2 mm) were prepared. The zirconia specimen and dentin blocks were bonded with resin cement before removal with an Er: YAG laser. Three disassembled dentin blocks were randomly selected, and the components of dentin surface elements were analyzed by energy dispersive X-ray spectroscopy (EDX). The removed dentin blocks were randomly divided into three groups (n = 33) based on the different surface treatments: control group (no treatment), sandblasting group (50 μm, Al2O3 sandblasting), and laser irradiation group (Er: YAG laser irradiation, parameters were set to 10 Hz, 60 mJ, 0.6 W). Three dentin blocks were randomly selected in each group for scanning electron microscopy (SEM) observation, and the residual resin on dentin surface of remaining 30 dentin blocks in each group were observed under an optical microscope at 20 times magnification. Scores were obtained using the adhesive remnant index (ARI) method. Three groups of dentin blocks (n = 30) that underwent different surface treatments were rebonded with resin cement according to standard procedures and then divided into two subgroups for aging (n = 15). One subgroup was subjected to a 37 ℃ water bath for 24 h, and the other subgroup was subjected to 5 000 thermal cycles after a 37 ℃ water bath for 24 h, and the micro-shear bonding strength of each group was measured. The microshear bonding strength of each group was measured, and fracture modes were analyzed. The differences of dentine surface ARI between the three groups, as well as the inter-group differences in fracture mode, and bonding strength, and the intra-group differences before and after aging were compared between the three groups. Results: When zirconia was removed by Er: YAG laser, there was no obvious damage on the dentin surface, but C and Si elements in dentin increased significantly. After different surface treatments, the ARI scores of the sandblasting and laser irradiation groups were lower than those of the control group (P<0.05), while ARI was not significantly different between the sandblasting and laser irradiation groups (P>0.05). The dentin surface morphology was also different. There was a large amount of residual resin on the dentin surface of the control group. In the sandblasting group, the residual resin was lower, the dentin surface was rough, and the dentin tubules were visible. A large amount of residual resin was observed on the dentin surface of the laser irradiation group. After 24 h of water bath at 37 ℃, the bonding strengths of the control group, sandblasting group, and laser irradiation group were (6.13 ± 2.40) MPa, (9.39 ± 2.00) MPa, and (5.85 ± 1.44) MPa, respectively, and the bonding strength of the sandblasting group was significantly higher than that of the other two groups (P<0.05). After being subjected to 24 h of water bath at 37 ℃ and 5 000 thermal cycles, the bonding strengths of the control group, sandblasting group, and laser irradiation group were (5.39 ± 0.83) MPa, (8.45 ± 1.20) MPa and (4.84 ± 1.43) MPa, respectively. The bonding strength of the sandblasting group was significantly higher than that of the other two groups (P<0.05). There was no significant difference between the control group, sandblasting group, and laser irradiation group before and after 5 000 thermal cycles following 24 h of water bath at 37 ℃ (P>0.05). In the control group, sandblasting group, and laser irradiation group, cohesive fracture was not observed. The fracture mode was mainly adhesive fracture. Before and after 5 000 thermal cycles, the frequency of mixed fracture in the sandblasting group was significantly higher than that in the other two groups (P<0.05). Conclusion Er: YAG laser removal of zirconia does not damage dentin, but a large amount of resin remains on the dentin surface after removal. The sandblasting process can effectively remove these residual resins, thereby improving the dentine rebonding effect.