Objective To investigate the correlation between G protein-coupled receptor family C group 6 member A(GPRC6A)gene polymorphisms and their expression and pulmonary infections in elderly patients with chronic heart failure(CHF).Methods 138 elderly CHF patients admitted to the Xianyang First People's Hospital from January 2021 to January 2024 were selected as the research subjects,and were divided into an infected group(n=42)and an uninfected group(n=96)based on their lung infection status.Polymerase chain reaction(PCR)was used to detect polymorphisms at the rs6901250 and rs1606365 loci of the GPRC6A gene.The allele and genotype frequency distributions of the infected and uninfected groups were compared.Logistic regression modeling was used to analyze the s6901250 and rs1606365 loci under three genetic models(co-dominant,dominant and reces-sive)and lung infections in elderly patients with CHF.Real-time fluorescence quantitative PCR(RT-qPCR)method was used to detect the expression level of GPRC6A gene.The predictive value of the mRNA expression level of the GPRC6A gene for the development of pulmonary infections in elderly patients with CHF was analyzed by applying the receiver operator characteristic(ROC)curve.Results The distribution of genotypes at loci rs6901250 and rs1606365 of the GPRC6A gene in both the infected and uninfected groups of the lungs of elderly CHF patients conformed to the Hardy-Weinberg equilibrium law(χ2=0.199～0.376,all P>0.05),which was representative of the population.Compared with the uninfected group,the frequency of allele A at locus rs6901250(57.14%vs 41.67%)was significantly higher in the infected group,Allele G(54.76%vs.37.50%)and genotype GG(14.06%vs 29.99%)frequencies were significantly higher at locus rs1606365,and the differences were statistically significant(χ2=5.628,7.114,6.849,all P<0.05).At locus rs6901250,in the co-dominant model(GG vs AA)and the dominant model(GA+AA vs GG),the elderly CHF patients with AA genotype the risk of lung infection was higher than that of GG genotype(OR=1.753,1.546,all P<0.05);.rs1606365 locus showed that the risk of lung infection was higher than that of CC genotype in el-derly CHF patients with GG genotype under all three genetic models of co-dominant model(CC vs GG),dominant model(CG+GG vs CC)and recessive model(CG+CC vs GG)(OR=1.833,1.741,0.695,all P<0.05).The mRNA expression level of GPR-C6A gene in the lung-infected group of elderly CHF patients(1.43±0.35)was significantly higher than that in the uninfected group(1.02±0.21),and the difference was statistically significant(t=8.515,P<0.001).The results of the ROC curve analysis showed that the GPRC6A gene expression level predicted lung infection in elderly CHF patients with an AUC value of 0.895,a cut-offvalue of 1.37,and sensitivity and specificity of 85.7%and 66.7%,respectively.Conclusion The AA genotype at the rs6901250 locus and the GG genotype at the rs1606365 locus of the GPRC6A gene increased the risk of developing lung infec-tions in elderly patients with CHF.MRNA expression levels of the GPRC6A gene were elevated in the infected group,and its ex-pression level could be used as a predictive indicator for the development of lung infections in elderly patients with CHF.

Objective To investigate the correlation between G protein-coupled receptor family C group 6 member A(GPRC6A)gene polymorphisms and their expression and pulmonary infections in elderly patients with chronic heart failure(CHF).Methods 138 elderly CHF patients admitted to the Xianyang First People's Hospital from January 2021 to January 2024 were selected as the research subjects,and were divided into an infected group(n=42)and an uninfected group(n=96)based on their lung infection status.Polymerase chain reaction(PCR)was used to detect polymorphisms at the rs6901250 and rs1606365 loci of the GPRC6A gene.The allele and genotype frequency distributions of the infected and uninfected groups were compared.Logistic regression modeling was used to analyze the s6901250 and rs1606365 loci under three genetic models(co-dominant,dominant and reces-sive)and lung infections in elderly patients with CHF.Real-time fluorescence quantitative PCR(RT-qPCR)method was used to detect the expression level of GPRC6A gene.The predictive value of the mRNA expression level of the GPRC6A gene for the development of pulmonary infections in elderly patients with CHF was analyzed by applying the receiver operator characteristic(ROC)curve.Results The distribution of genotypes at loci rs6901250 and rs1606365 of the GPRC6A gene in both the infected and uninfected groups of the lungs of elderly CHF patients conformed to the Hardy-Weinberg equilibrium law(χ2=0.199～0.376,all P>0.05),which was representative of the population.Compared with the uninfected group,the frequency of allele A at locus rs6901250(57.14%vs 41.67%)was significantly higher in the infected group,Allele G(54.76%vs.37.50%)and genotype GG(14.06%vs 29.99%)frequencies were significantly higher at locus rs1606365,and the differences were statistically significant(χ2=5.628,7.114,6.849,all P<0.05).At locus rs6901250,in the co-dominant model(GG vs AA)and the dominant model(GA+AA vs GG),the elderly CHF patients with AA genotype the risk of lung infection was higher than that of GG genotype(OR=1.753,1.546,all P<0.05);.rs1606365 locus showed that the risk of lung infection was higher than that of CC genotype in el-derly CHF patients with GG genotype under all three genetic models of co-dominant model(CC vs GG),dominant model(CG+GG vs CC)and recessive model(CG+CC vs GG)(OR=1.833,1.741,0.695,all P<0.05).The mRNA expression level of GPR-C6A gene in the lung-infected group of elderly CHF patients(1.43±0.35)was significantly higher than that in the uninfected group(1.02±0.21),and the difference was statistically significant(t=8.515,P<0.001).The results of the ROC curve analysis showed that the GPRC6A gene expression level predicted lung infection in elderly CHF patients with an AUC value of 0.895,a cut-offvalue of 1.37,and sensitivity and specificity of 85.7%and 66.7%,respectively.Conclusion The AA genotype at the rs6901250 locus and the GG genotype at the rs1606365 locus of the GPRC6A gene increased the risk of developing lung infec-tions in elderly patients with CHF.MRNA expression levels of the GPRC6A gene were elevated in the infected group,and its ex-pression level could be used as a predictive indicator for the development of lung infections in elderly patients with CHF.

Objective:To investigate the value of immune inflammatory index in predic-ting the therapeutic efficacy of neoadjuvant chemoradiotherapy for esophageal squamous cell carci-noma (ESCC).Methods:The retrospective case-control study was conducted. The clinicopatholo-gical data of 163 patients with ESCC who were admitted to Zhongshan Hospital of Fudan University from December 2015 to December 2020 were collected. There were 135 males and 28 females, aged (62±8)years. All 163 patients underwent neoadjuvant chemoradiotherapy and radical resection for ESCC. Observation indicators: (1) relationship between immune inflammatory index and clinical characteristic in patients; (2) relationship between immune inflammatory index and efficacy of neoadjuvant chemoradiotherapy in patients; (3) influencing factor analysis for pathologic complete response and good response of tumor regression grade after neoadjuvant chemoradiotherapy; (4) efficiency of immune inflammatory index in predicting efficacy of neoadjuvant chemoradiotherapy. Measurement data with normal distribution were represented as Mean± SD. Count data were described as absolute numbers, and comparison between groups was conducted using chi-square test. Comparison of ordinal data was conducted using the rank sum test. The receiver operating characteristic (ROC) curve was used to determine the optimal cut-off value. Univariate and multi-variate analyses were conducted using the Logistic regression model. The area under the curve (AUC) of ROC curve was used to evaluate the efficiency of predictive model. Results:(1) Relationship between immune inflammatory index and clinical characteristic in patients. ① Optimal cut-off value of systemic immune-inflammation index (SII), neutrophil-lymphocyte ratio (NLR), platelet-lympho-cyte ratio (PLR). Results of ROC curve analysis showed that the AUC of SII, NLR, PLR in predicting efficacy of neoadjuvant chemoradiotherapy for patients with ESCC was 0.70(95% confidence interval as 0.61?0.77), 0.78(95% confidence interval as 0.69?0.84), 0.79(95% confidence interval as 0.70?0.85), respectively, with the maximum value of Youden index and the optimal cut-off value as 0.25, 0.32, 0.52 and 446×10 9/L, 2.09, 138. ② Relationship between SII, NLR, PLR and clinical charac-teristic in patients. According to the optimal cut-off value of SII, NLR, PLR, all 163 patients were divided into cases with SII <446×10 9/L as 99, cases with SII ≥446×10 9/L as 64, cases with NLR <2.09 as 107, cases with NLR ≥2.09 as 56, cases with PLR<138 as 88, cases with PLR ≥138 as 75, respectively. There was a significant difference in clinical N staging of tumor in patients with SII <446×10 9/L and SII ≥446×10 9/L ( P<0.05). There were significant differences in clinical N staging and clinical TNM staging of tumor in patients with NLR<2.09 and NLR≥2.09 ( P<0.05). (2) Relationship between immune inflammatory index and efficacy of neoadjuvant chemoradiotherapy in patients. Of 163 patients undergoing neoadjuvant chemoradiotherapy, there were 54 cases with pathologic complete response and 109 cases without pathologic complete response, 94 cases with good response of tumor regression grade and 69 cases with poor response of tumor regression grade. Of the 54 patients with pathologic complete response, cases with SII <446×10 9/L and SII ≥446×10 9/L, cases with NLR <2.09 and NLR ≥2.09, cases with PLR <138 and PLR ≥138 before neoadjuvant chemoradiotherapy were 42 and 12, 47 and 7, 48 and 6, respectively. The above indicators were 57 and 52, 60 and 49, 40 and 69 in the 109 cases without pathologic complete response. There were significant differences in the above indicators between patients with pathologic complete response and without pathologic complete response ( χ2=9.83, 16.39, 39.60, P<0.05). Of the 94 cases with good response of tumor regression grade, cases with SII <446×10 9/L and SII ≥446×10 9/L, cases with NLR <2.09 and NLR ≥2.09, cases with PLR <138 and PLR ≥138 before neoadjuvant chemoradiotherapy were 59 and 35, 78 and 16, 56 and 38, respectively. The above indicators were 40 and 29, 29 and 40, 32 and 37 in the 69 cases with poor response of tumor regression grade. There was no significant difference in the SII and PLR ( χ2=0.38, 2.79, P>0.05) and there was a significant difference in the NLR ( χ2=29.59, P<0.05) between patients with good response of tumor regression grade and poor response of tumor regre-ssion grade. (3) Influencing factor analysis for pathologic complete response and good response of tumor regression grade after neoadjuvant chemoradiotherapy. Results of multivariate analysis showed that PLR <138 before neoadjuvant chemoradiotherapy was an independent protective factor for pathologic complete response in ESCC patients undergoing neoadjuvant chemoradiotherapy ( odds ratio=1.98, 95% confidence interval as 1.56?2.51, P<0.05) and NLR <2.09 before neoadjuvant chemo-radiotherapy was an independent protective factor for good response of tumor regression grade ( odds ratio=2.50, 95% confidence interval as 1.40?4.46, P<0.05). (4) Efficiency of immune inflam-matory index in predicting efficacy of neoadjuvant chemoradio-therapy. The AUC of PLR <138 before neoadjuvant chemoradiotherapy in predicting pathologic complete response of ESCC patients undergoing neoadjuvant chemoradiotherapy was 0.79(95% confidence interval as 0.64?0.87, P<0.05), with the sensitivity, specificity and Youden index as 0.89, 0.63 and 0.52, respectively. The AUC of NLR <2.09 before neoadjuvant chemoradiotherapy in predic-ting good response of tumor regression grade of ESCC patients undergoing neoadjuvant chemoradio-therapy was 0.76 (95% confidence interval as 0.64?0.81, P<0.05), with the sensitivity, specificity and Youden index as 0.83, 0.58 and 0.41, respectively. Conclusion:The PLR<138 and NLR <2.09 before neoadjuvant chemoradiotherapy are independent protective factors for the pathologic complete response and good response of tumor regression grade, respectively, of ESCC patients undergoing neoadjuvant chemoradiotherapy, and both of them can predict the curative effect of neoadjuvant chemoradiotherapy well.

Objective:To evaluate the feasibility and clinical outcomes of navigation-assisted total knee arthroplasty (TKA) using adjusted restricted kinematic alignment (arKA).Methods:Data of 14 consecutive cases of OrthoPilot navigation-assisted TKA using arKA from October 2019 to September 2021 were retrospectively analyzed, including 3 males and 9 females. The average age was 67.71±8.96 years with mean body mass index (BMI) 25.94±3.12 kg/m 2. 27 consecutive patients who underwent navigation-assisted TKA using aMA during the same period were assessed as the control group. There were no significant differences in gender, age or BMI between the two groups. Intraoperative parameters including operative duration, tibia resection angle, frontal femoral angle, axial femoral angle, joint line translation, medial and lateral gap in extension and flexion position were recorded. Radiographic parameters including hip-knee-ankle (HKA) angle, coronal femoral component angle (cFCA), coronal tibial component angle (cTCA), sagittal femoral component angle (sFCA) and sagittal tibial component angle (sTCA) were measured. Functional outcomes were assessed by Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Hospital for Special Surgery (HSS) score. Surgery-related complications were recorded. Results:All cases were followed up. The mean follow-up of arKA group was 18.57±6.98 months and follow-up of aMA group was 22.15±4.91 months. The intraoperative tibial resection was 3.07°±1.00° in arKA group versus 0.67°±0.56° in aMA group ( P<0.05). The lateral cutting height of tibia was 9.07±1.82 mm in arKA group versus 6.89±2.94 mm in aMA group ( P<0.05). The lateral gap in flexion was 1.71±0.83 mm in arKA group versus 1.04±0.71 mm in aMA group ( P<0.05). The difference of medial-lateral flexion laxity was 1.14±0.86 mm in arKA group versus 0.41±0.75 mm in aMA group ( P<0.05). The postoperative HKA angle was 174.10°±1.63° in arKA group versus 177.12°±2.07° in aMA group ( P<0.05). The cTCA was 87.58°±0.85° in arKA group versus 89.14°±1.23° in aMA group ( P<0.05). The cFCA was 93.10°±1.75° in arKA group versus 90.41°±3.01° in aMA group ( P<0.05). There was no statistical difference between the two groups in sFCA (1.30°±0.82° vs. 1.56°±1.19°), sTCA (87.16°±0.95° vs. 87.79°±1.04°) and femoral notching (7.1% vs. 11.1%). The preoperative HSS score in arKA group was 46.07±4.68 and HSS score at 1 month postoperatively was 73.86±3.48 ( P<0.05). The preoperative HSS score in aMA group was 47.04±4.52 and HSS score at 1 month postoperatively was 74.04±3.57 ( P<0.05). There was no statistical difference between the two groups in WOMAC score (12.93±2.37 vs. 12.63±2.34) and HSS score (86.86±2.74 vs. 86.11±2.95) at 6 months postoperatively. 2 cases (14.3%) in arKA group and 5 cases (18.5%) in aMA group had deep venous thrombosis (χ 2=0.12, P=0.733). Conclusion:Navigation-assisted TKA using arKA offers the surgeons a new alignment option for severe knee deformity with satisfactory clinical outcomes, the arKA technique has advantages in soft tissue protection and gap balance regulation compared to aMA technique.

Objective To study the association between serum testosterone level and insulin resistance (IR) in elderly male hypertensive patients.Methods One hundred and seven elderly male hypertensive patients were divided into IR group (n=44) and IR-free group (n=63).Their total TST level was measured,their FAI and TSI were assayed.The patients were further divided into TST≥14 nmol/L group (n=72) and TST＜14 nmol/L group (n=35).The association between serum testosterone level and IR in elderly male hypertensive patients was analyzed.Results The serum TST level,FAI and TSI were significantly lower in IR group than in IR-free group (12.02±2.66 nmol/L vs 15.98±3.98 nmol/L;20.16％±2.75％ vs 28.53％±4.74％;2.26±0.49 nmol/U vs 3.21±0.55 nmol/U,27.67％±5.49％ vs 25.98％±4.98％;2.95±0.39 nmol/U vs 2.78±0.64 nmol/U,P＜0.05).The FAI and TSI were significantly higher in hypertention grade 1 patients than in hypertension grade 3 patients (P＜0.05).The IR was significantly lower while the serum TST level,FAI and TSI were significantly higher in TST≥14 nmol/L group than in TST＜14 nmol/L group (33.3％ vs 57.1％,P=0.019;18.43±3.41 nmol/L vs 12.15±2.23 nmol/L,P=0.002;32.49％±5.67％ vs 24.57％±6.94％,P=0.036;3.53±0.87 nmol/U vs 2.55±0.62 nmol/U,P=0.016).TST,FAI and TSI were negatively associated with HOMA-IR (r=-0.406,r=-0.469,r=-0.429,P=0.000).Conclusion Low serum TST level is a risk factor for IRin elderly male hypertensive patients.

Objective To observe the protective effect of dexmedetomidine(Dex)at different doses com-bined with ulinastatin in lung resection patients with one lung ventilation. Methods 80 patients having undergone unilateral lung resection were divided into four groups randomly:control group(C group)and groups Dex 1-3,20 cases in each group.One lung ventilation(OLV)was used in all the groups during operation.The patients in groups Dex 1-3 were treated with 0.5,1.0,2.0 μg/kg combined with ulinastatin,and the C group with amount of normal sa-line instead.The comparisons were done among the four groups in terms of SOD,L-6,IL-10,serum malondialde-hyde(MDA)concentration at 5 min after endotracheal intubation(T0),30 min(T1),60 min(T2),120 min (T3)as well as the levels of FVC,FEVl and FEVl/FVC at 24 h,48 h and 72 h after surgery. Results In the groups C and Dex 1,SOD decreased at T1-4 and IL-6,MDA and IL-10 at T2-4 rose.SOD decreased at T2-4 in groups Dex 2-3 and MDA,IL-6 and IL-10 rose.Compared with group C,the levels of SOD and IL-10 at T2-4 in groups Dex 1-2 and at T1-4 in group Dex 3 rose. In groups Dex 1-3,postoperative FVC,FEVl and FEVl/FVC rose.Compared with group Dex 1 or 2 respectively,SOD and IL-10 at T2-4 in group Dex 3 significantly rose,but MDA and IL-6 significantly declined;FVC,FEVl and FEVl/FVC significantly rose 48 h and 72 h after surgery (P<0.05). Conclusion Dex combined with ulinastatin has a protective effect for patients with one lung ventila-tion after lung resection,with the best-suggested dose of 1.0 μg/kg.

Objective To analyze the spatial distribution patterns of rodent community and the risk factors of disease transmission in natural foci of Xiji County,Ningxia,in order to provide a scientific basis for disease control and prevention.Methods Rodents were captured at different habitats in different latitudes which were selected with a stratified sampling method in 2012-2013.Capture rate of different rodent species and spatial distribution patterns of the animal community were analyzed.Antigen and antibody of hantavirus were detected in lung tissue and blood of the rodents with immunofluorescence and enzyme-linked immunosorbent assay (ELISA),respectively.Serum F1 antibody of Yersinia pestis (Y.pestis) was detected with indirect hemagglutination test and Y.pestis from liver and spleen tissue was cultured in vitro.Results Fourteen species of rodents were captured,belonging to 2 orders,7 families and 9 genera.Among them,ground squirrels and wood mouse were dominant species,accounted for 49.56％ (112/226) and 34.51％ (78/226) of the community,respectively.Infections of hantavirus and Y.pestis were not found in the rodent's community.Conclusion With the improvement of ecological environment in Xiji County,the spatial distribution patterns of rodent community is changing; the risk of zoonotic plague is reduced,but the risk of hemorrhagic fever with renal syndrome is being.

BACKGROUND:Bone marrow mesenchymal stem cel transplantation is considered as a promising therapy for spinal cord injury. How to more effectively promote the survival of bone marrow mesenchymal stem cel s in the area of spinal cord injury and to accelerate the recovery of motor function after spinal cord injury is a current study focus. Previous studies have found that low-frequency electromagnetic fields can promote bone marrow mesenchymal stem cel proliferation and differentiation, but whether the low-frequency electromagnetic fields can be applied to bone marrow mesenchymal stem cel transplantation for treatment of spinal cord injury requires further studies. OBJECTIVE:To discuss the effects of low-frequency electromagnetic fields on motor function of spinal cord injury rats after transplantation of bone mesenchymal stem cel s. METHODS:Sixty-four rat models of incomplete spinal cord injury at T 10 were established by compression method and then randomized into control group, transplantation group (bone mesenchymal stem cel transplantation), electromagnetic field group and combination group (electromagnetic field+bone mesenchymal stem cel transplantation). After successful modeling, bone mesenchymal stem cel s labeled with 5-bromo-2'-deoxyuridine were injected into the original injured site in the transplantation group and combination group, which were isolated and purified with the fast adherence method;while alpha-minimum essential medium was injected into the electromagnetic field group and control group for instead. At 24 hours post-operation, the electromagnetic field group and combination group were explored to low-frequency electromagnetic fields (frequency 50 Hz, magnetic indaction intensity 5 mT) for 60 minutes per day. RESULTS AND CONCLUSION:After cel transplantation for 21 days, the Basso, Beattie, and Bresnahan scores in the combination group was higher than the other groups (P<0.05). 5-Bromo-2'-deoxyuridine positive cel s grew wel , and integrated into the normal spine;syringomyelia was reduced, and the number of spinal neural cel s was increased in the combination group. In addition, glial fibril ary acidic protein expression was decreased in the combination group, while matrix metal oproteinase 2 expression was increased. It indicates that low-frequency electromagnetic fields could promote recovery of motor function in the spinal cord injury rats transplanted with bone mesenchymal stem cel s, which could be associated that low-frequency electromagnetic fields facilitate the survival of transplanted bone mesenchymal stem cel s, up-regulate the expression of matrix metal oproteinase 2, and reduce glial scar formation in the spinal cord injured site.

BACKGROUND:The repair and management of ful-thickness skin defects resulting from burns and chronic wounds remain a significant unmet clinical chal enge. Using epidermal stem cel s and keratinocyte growth factor for ful-thickness wound repair is a promising approach. Low-frequency electromagnetic fields which are a non-invasive physical stimulation therapy have been recognized as a good method to enhance wound healing. OBJECTIVE:To develop a new strategy to accelerate wound healing by transplanting transfected epidermal stem cel s and keratinocyte growth factor and treating with low-frequency electromagnetic fields in a mouse model. METHODS:Epidermal stem cel s from Sprague-Dawley neonatal rats were isolated and cultured in vitro, then the cel s were labeled with 5-bromo-2-deoxyuridine and transfected by Ad-KGF, a recombinant adenovirus carrying the keratinocyte growth factor. Mice were given to create ful thickness skin wound on the dorsum and randomly assigned to four groups:control group, transplantation of epidermal stem cel s group, transplantation of keratinocyte growth factor gene modified epidermal stem cel s group, and transplantation of keratinocyte growth factor gene modified epidermal stem cel s plus low-frequency electromagnetic field exposure group. RESULTS AND CONCLUSION:The best healing pattern was observed in the keratinocyte growth factor gene modified epidermal stem cel s plus low-frequency electromagnetic field exposure group (P<0.05) at days 9 and 16. 5-Bromo-2-deoxyuridine labeled cel s existed in the wound in the treated groups at day 9. A significantly increased expression of endogenous keratinocyte growth factor was detected in the transplantation of Keratinocyte Growth Factor gene modified epidermal stem cel s group, and transplantation of keratinocyte growth factor gene modified epidermal stem cel s plus low-frequency electromagnetic field exposure group at day 16. A wel-advanced epithelialization was observed in transplantation of keratinocyte growth factor gene modified epidermal stem cel s plus low-frequency electromagnetic field exposure group at days 16 and 30. These results suggest that low-frequency electromagnetic fields enhanced wound healing fol owing the transplantation of keratinocyte growth factor gene modified epidermal stem cel s.

Objective To establish a convenient ~(13)C-breath test system in live mice,and investigate the value of ~(13)C-methacetin breath test(~(13)C-MBT) in the diagnosis of acute liver damage of mice with domestically synthesized ~(13)C-methacetin. Methods Domestically synthesized ~(13)C.methacetin was prepared from aeamol by methylation. Abdominal injection of CCl_4 was adopted to duplicate acute liver damage of mice,then the mice were housed under normal laboratory condition for a whole month to gain recovery,which were indentified by hepatic pathological examinations and biochemical teats of liver function.After fasting, the mice were orally administered ~(13)C-methacetin,and the expired air was collected at various time points. Infrared spectrometer was employed, and delm over baseline(DOB) curves of ~(13)C-exhalation were drawn. Results Six to eight min after administration of ~(13)C-methacetin,the rate of ~(13)C-exhalation peaked in control group(51.9±2.04), and decreased thereafter. Sixteen min after administration of ~(13)C-methacetin,the rate of ~(13)JC-exhalation peaked in model group(26.37±5.74), and decreased thereafter.There were significant differences between these two groups(P<0.05).There was no significant difference in peak value and time to reach the peak on DOB curves of ~(13)C-methacetin breath test after the two groups of mice were housed under the same condition for a month(P>0.05).Conclution ~(13)C-MBT facilitates the collection and evaluation of ~(13)CO_2 in the expired air of live mice,and yields precise reflection of alterations of liver function in acute liver injury and functional recovery.