Objective To explore the feasibility and rationality of advanced integrated two-stage laparoscopic simulation training course in standardized training of surgical residents.Methods From December 2019 to December 2021,the advanced integrated two-stage laparoscopic simulation training course was carried out among 2019-2020 surgical residents who received standardized training in our hospital.The course was divided into two stages.In the first stage,BEST(best essential surgical technology training)course,adopted Darwin? endoscopic training system,Tianyan? endoscopic training system,Microport? 3D laparoscopic training system and simple simulative models were used.The second stage,BEST PLUS course,same platform as that in BEST course and in vitro animal models were used.The questionnaire survey method(before and after class questionnaire)was adopted to evaluate the curriculum setting,such as curriculum form,simulators,teaching method,time arrangement,curriculum difficulty,training effect,curriculum satisfaction and so on.Results A total of 37 surgical residents completed the two-stage course training and the questionnaire survey.The overall satisfaction rate with the curriculum setting was 100%.There were 32 residents(86.5%)thought that first stage training course could significantly improve their clinical skills,35 residents(94.6%)thought that second stage training course could significantly improve their clinical skills,and 36 resident(97.3%)thought that the first stage curriculum could significantly help them improve performance in the second stage curriculum.Conclusions The trainees had a high degree of recognition and satisfaction for the advanced integrated two-stage laparoscopic simulation training course.The overall design of course was reasonable and feasible,and was attractive to trainees.

Background Aluminum and fluoride are neurotoxic, and aluminum exposure alone is closely related to the overall cognitive function of operational workers. It is unclear about the effect of aluminum and fluoride interactions on cognitive function. Objective To evaluate a potential interaction effect of blood aluminum and urinary fluoride on the overall cognitive function of workers working in an aluminum plant. Methods Using cluster sampling, 230 workers in the electrolysis workshop of an aluminum group company in Shanxi Province were selected, and plasma aluminum concentrations were determined by inductively coupled plasma mass spectrometry (ICP-MS) and urinary fluoride by ion-selective electrode. The study participants were divided into a low blood aluminum group and a high blood aluminum group according to the median (M) of blood aluminum concentration, and a low urinary fluoride group and a high urinary fluoride group by a predetermined cutoff point (2.160 mg·L⁻¹). The Montreal Cognitive Assessment-Beijing (MoCA-BJ) was used to assess overall cognitive function of the workers. Logistic regression model was used to analyze the relationship between blood aluminum, urinary fluoride, and mild cognitive impairment (MCI), including multiplicative interaction analysis and correlation analysis; R language was used to fit an additive interaction model of blood aluminum and urinary fluoride on MCI and to calculate synergy index (S), relative excess risk due to interaction (RERI), and attributable proportion due to interaction (API). Results Among the 230 operational workers, the median blood aluminum concentration (P₂₅, P₇₅) was 40.11 (25.16, 58.89) µg·L⁻¹, and there were 104 cases of abnormal urinary fluoride, with an abnormality rate of 45.2%. There was a multiplicative interaction (OR=7.783, 95%CI: 1.377, 43.991) and no additive interaction (RERI=0.030, 95%CI: −0.498, 0.559; API=0.018, 95%CI: −0.279, 0.316; S=1.049, 95%CI: 0.519, 2.118) for the effect between blood aluminum and urinary fluoride on overall cognitive function of the workers. The logistic regression analysis showed that the risk of MCI was 12.105 (95%CI: 2.802, 52.287) times higher in workers with both high blood aluminum and high urinary fluoride than in those with low blood aluminum and low urinary fluoride, after adjusting for selected influencing factors. Conclusion Occupational exposure related high blood aluminum and high urinary fluoride are risk factors for cognitive dysfunction, and the coexistence of both indicators increases the risk of MCI in workers with occupational aluminum exposure, with a multiplicative interaction.

Objective:To analyze and summarize the implementation effect of basic essential surgical training (BEST) course of laparoscopic skills over the past 10 years and the practical experience in updating course content and models.Methods:The pre-class assessment questionnaires, basic laparoscopic operation assessment results, and post-class assessment questionnaires of the students who participated in the BEST course of laparoscopic skills were collected. According to the period of the course construction, the students were divided into two groups, namely students who used the course of single training system in the early stage (traditional group) and students who used the course integrating a variety of training systems after the course model was updated in the later stage (test group). The two groups were compared for the scores of track circle moving, tunnel crossing, and high and low columns, as well as their subjective evaluation of course setting and implementation effect. The t-test, Wilcoxon test, or chi-square test was conducted according to the data type using SPSS 13.0. Results:The time for 150 traditional group students to complete track circle moving, tunnel crossing, and high and low columns was 1.08 min (0.81 min, 1.60 min), 2.20 min (1.60 min, 3.27 min), and 4.86 min (3.28 min, 6.36 min), respectively, while the time for 75 test group students to complete the three operations was 1.27 min (0.87 min, 1.83 min), 2.57 min (1.58 min, 4.07 min), and 4.35 min (2.90 min, 6.42 min), respectively, with no significant difference between the two groups ( P>0.05). In terms of students' subjective evaluation of the course, a higher percentage of the test group students were satisfied with classroom environment, teaching method arrangement, training equipment, training opportunities, helping clinical work, and meeting pre-class expectations than those in the traditional group. Conclusion:The constantly updated BEST course can ensure the training quality of trainees and obtain their higher satisfaction. The benefits of this course in clinical practice can be further verified through long-term follow-up of these trainees.

Objective: To examine the correlation between visuospatial construction ability and occupational aluminum exposure among aluminum workers, so as to provide the evidence for early protection of occupational injury among aluminum workers. Methods: A total of 442 workers in an aluminum factory in Shanxi Province were selected using a cluster sampling method, and participants' demographic features and occupational history were collected. The blood aluminum concentration was measured using inductively coupled plasma mass spectrometry (ICP-MS), and the visuospatial construction ability was evaluated with the Cube Copying Test (CCT) of the Chinese version of the Montreal Cognitive Assessment (MoCA). The correlation between the visuospatial construction ability and blood aluminum concentration was examined using a multivariable logistic regression model. Results: A total of 442 aluminum workers were enrolled, and all participants were male, with a mean age of (43.40±7.31) years, labor service duration of (23.64±8.35) years and a mean blood aluminum concentration of 33.87 µg/L. Of all participants, there were 206 workers with impaired visuospatial construction ability (46.61%), including 127 workers with blood aluminum concentrations of >33.87 µg/L (61.65%); 190 workers with educational duration of 6 to 9 years (92.23%), 118 electrolytic aluminum workers (57.28%), 114 workers with work shifts (55.34%), and 123 workers with a very good sleep quality (59.71%). Multivariable logistic regression analysis revealed that blood aluminum concentrations of >33.87 µg/L (OR=2.490, 95%CI: 1.531-4.052), educational duration of 6 years or more (OR: 0.075-0.246, 95%CI: 0.015-0.622), work type as a non-electrolytic aluminum worker (OR=0.838, 95%CI: 0.425-0.987), work shift (OR=1.179, 95%CI: 1.078-1.435) and a very good sleep quality (OR=0.104, 95%CI: 0.012-0.896) significantly correlated with impaired visuospatial construction ability among aluminum worker. Conclusion Impaired visuospatial construction ability correlates with occupational aluminum exposure among aluminum workers.

Objective:To evaluate the effect of irisin on ventilator-induced lung injury (VILI) in rats and the relationship with expression of NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasomes.Methods:Thirty-six SPF-grade healthy adult male Sprague-Dawley rats, aged 6-8 weeks, weighing 220-300 g, were divided into 3 groups ( n=12 each) using a random number table method: control group (group C), group VILI and irisin group (group I). All the groups underwent tracheotomy and intubation, group C kept spontaneous breathing for 4 h, and the animals were mechanically ventilated for 4 h in VILI and I groups.Irisin 1 μg/kg was injected via the tail vein at 30 min before tracheal intubation in group I, and the equal volume of normal saline mixture (normal saline∶phosphate buffer solution containing 5% trehalose=1∶9) were given in the other 2 groups via the tail vein.The rats were mechanically ventilated with the tidal volume of 20 ml/kg, respiratory rate 80 breaths/min, inspiratory/expiratory ratio 1∶1, inspired oxygen fraction ratio 21% and positive end-expiratory pressure 0.Blood samples from left femoral artery were collected before tracheal intubation and at the end of mechanical ventilation for detection of PaO 2.The animals were sacrificed and the lung tissue samples and bronchoalveolar lavage fluid (BALF) were then collected for examination of the pathological changes (under the light microscope), and for determination of wet to dry weight (W/D) ratio and the concentrations of total protein in BALF and interleukin-1β (IL-1β) and IL-18 in BALF and serum (by enzyme-linked immunosorbent assay), level of reactive oxygen species (ROS) in alveolar macrophages in BALF (by DCFH-DA) and the expression of NLRP3, apoptosis-associated speck-like protein (ASC) and caspase-1 protein and mRNA in lung tissues (by Western blot and by quantitative reverse transcription polymerase chain reaction). The pathological changes of the lung were scored. Results:Compared with group C, PaO 2 was significantly decreased at the end of mechanical ventilation, lung injury score and W/D ratio were increased, concentration of total protein and ROS level in alveolar macrophages in BALF and concentrations of BALF, IL-1β and IL-18 in serum were increased, and the expression of NLRP3, ASC and caspase-1 protein and mRNA in lung tissues was up-regulated in group VILI and group I ( P<0.01). Compared with group VILI, PaO 2 was significantly increased at the end of mechanical ventilation, lung injury score and W/D ratio were decreased, concentration of total protein and ROS level in alveolar macrophages in BALF and concentrations of BALF, IL-1β and IL-18 in serum were decreased, and the expression of NLRP3, ASC and caspase-1 protein and mRNA in lung tissues was down-regulated in group I ( P<0.05). Conclusion:Irisin can reduce VILI, and the mechanism is related to inhibiting activation of NLRP3 inflammasome and reducing inflammatory response in rats.

Objective:To investigate the effect of irisin on pyroptosis in rats with ventilator-induced lung injury.Methods:Thirty-six healthy clean-grade male Sprague-Dawley rats, weighing 200-250 g, aged 6-8 weeks, were divided into 3 groups ( n=12 each) using a random number table method: control group (group C), ventilator-induced lung injury group (group V) and ventilator-induced lung injury plus irisin group (group V+ I). In group V+ I, irisin 1 μg/kg was injected via the tail vein before mechanical ventilation.The animals were mechanically ventilated (tidal volume of 40 ml/kg, respiratory rate 60 breaths/min, inspiratory/expiratory ratio 1∶2, positive end expiratory pressure 0 and inspired oxygen fraction ratio 21%.Blood samples were then taken from the femoral artery for blood gas analysis, and PaO 2 was recorded.Bronchoalveolar lavage fluid (BALF) was collected, the total protein concentrations in BALF were measured, and the concentrations of BALF and serum interleukin-1β (IL-1β) and IL-18 were measure by enzyme-linked immunosorbent assay.The lung tissues were obtained for determination of the pathological changes after HE staining which were scored, wet to dry weight (W/D) ratio, expression of pyroptosis-related proteins N-terminal gasdermin D (GSDMD-N) and caspase-1 protein and mRNA (by Western blot or using real-time polymerase chain reaction). Results:Compared with group C, the lung injury score and W/D ratio were significantly increased, PaO 2 and OI were decreased, the total protein concentrations in BALF, concentrations of IL-1β and IL-18 in BALF and serum were increased, and the expression of caspase-1 and GSDMD-N protein and mRNA was up-regulated in group V ( P<0.01). Compared with group V, the lung injury score and W/D ratio were significantly decreased, PaO 2 and OI were increased, the total protein concentrations in BALF, concentrations of serum IL-1β and IL-18 in BALF and serum were decreased, and the expression of caspase-1 and GSDMD-N protein and mRNA was down-regulated in group V+ I ( P<0.01). Conclusion:The mechanism by which irisin reduces ventilator-induced lung injury is probably related to inhibiting pyroptosis in rats.

Objective:To primarily investigate the application value of glasses-free three-dimensional (3D) laparoscopy system in laparoscopic radical resection of gastrointestinal malignant tumors.Methods:The retrospective cohort study was conducted. The clinical data of 165 patients with gastrointestinal malignant tumors who were admitted to the Ruijin Hospital of Shanghai Jiaotong University School of Medicine between October 2018 and May 2019 were collected. There were 99 males and 66 females, aged from 28 to 86 years, with a median age of 63 years. There were 68 of 165 patients with gastric cancer and 97 with colorectal cancer. Sixteen patients with gastric cancer who underwent laparoscopic radical gastrectomy using the glasses-free 3D laparoscopy system were divided into glasses-free 3D gastric cancer group, and 52 patients with gastric cancer who underwent laparoscopic radical gastrectomy using the polarized glasses 3D laparoscopy system were divided into polarized glasses 3D gastric cancer group. Nineteen patients with colorectal cancer who underwent laparoscopic radical colectomy or proctectomy using the glasses-free 3D laparoscopy system were divided into glasses-free 3D colorectal cancer group, and 78 patients with colorectal cancer who underwent laparoscopic radical colectomy or proctectomy using the polarized glasses 3D laparoscopy system were divided into polarized glasses 3D colorectal cancer group. Observation indicators: (1) operative situations of patients with gastric cancer; (2) postoperative recovery of patients with gastric cancer; (3) postoperative pathological examination results of patients with gastric cancer; (4) operative situations of patients with colorectal cancer; (5) postoperative recovery of patients with colorectal cancer; (6) postoperative pathological examination results of patients with colorectal cancer; (7) follow-up. Follow-up was conducted by outpatient examination or telephone interview to detect complications and survival of patients up to the postoperative 30th day. Measurement data with skewed distribution were represented as M ( P25, P75) or M (range), and comparison between groups was analyzed by the Mann-Whitney U test. Count data were represented as absolute numbers or percentages, and comparison between groups was analyzed using the chi-square test or Fisher exact probability. Results:(1) Operative situations of patients with gastric cancer: all the 68 gastric cancer patients received successfully laparoscopic radical gastrectomy, without intraoperative complication or conversion to laparotomy. Cases with distal gastrectomy or total gastrectomy(surgical methods) , operation time, volume of intraoperative blood loss were 11, 5, 195 minutes(169 minutes, 214 minutes), 20 mL (10 mL, 90 mL) in patients of the glasses-free 3D gastric cancer group, and 31, 21, 196 minutes(173 minutes, 222 minutes), 40 mL(20 mL, 100 mL) in patients of the polarized glasses 3D gastric cancer group, with no significant difference between the two groups ( χ2=0.432, Z=-0.362, -1.065, P>0.05). (2) Postoperative recovery of patients with gastric cancer: the time to first flatus, time to initial semi-fluid diet intake, duration of postoperative hospital stay were 2 days(2 days, 3 days), 6 days(5 days, 7 days), 10 days(9 days, 14 days) in patients of the glasses-free 3D gastric cancer group, and 2 days(2 days, 3 days), 6 days(5 days, 6 days), 11 days(9 days, 14 days) in patients of the polarized glasses 3D gastric cancer group, with no significant difference between the two groups ( Z=-0.163, -1.870, -0.570, P>0.05). The postoperative complication incidence of the glasses-free 3D gastric cancer group was 12.5%(2/16), including 1 case with duodenal stump fistula, 1 case with anastomotic bleeding. The postoperative complication incidence of the polarized glasses 3D gastric cancer group was 17.3%(9/52), including 2 cases with duodenal stump fistula, 2 cases with delayed gastric emptying, 1 case with pulmonary infection, 1 case with abdominal bleeding, 1 case with anastomotic leakage, 1 case with chylous fistula, 1 case with intestinal obstruction. All the patients with complications were cured after symptomatic supportive treatment. There was no significant difference in the complication incidence between the two groups ( χ2=0.209, P>0.05). (3) Postoperative pathological examination results of patients with gastric cancer: the tumor diameter, cases in stage T1, T2, T3, T4 (tumor T staging), cases with vascular invasion, cases with nerve invasion, cases with tumor nodule, cases in stage N0, N1, N2, N3 (tumor N staging), the number of positive lymph node, the number of lymph node dissected, cases with qualified lymph node dissected, cases in stage Ⅰ, Ⅱ, Ⅲ, Ⅳ (TNM clinical staging) were 3.0 cm(2.0 cm, 5.0 cm), 5, 3, 1, 7, 8, 5, 2, 3, 2, 4, 7, 6(1, 15), 28(22, 43), 15, 4, 3, 9, 0 in patients of the glasses-free 3D gastric cancer group, and 3.5 cm(2.0 cm, 6.0 cm), 13, 10, 4, 25, 19, 23, 2, 26, 6, 7, 13, 1(0, 7), 29(21, 39), 43, 21, 10, 20, 1 in patients of the polarized glasses 3D gastric cancer group. There was no significant difference in the tumor diameter, tumor T staging, cases with vascular invasion, cases with nerve invasion, cases with tumor nodule, the number of lymph node dissected, cases with qualified lymph node dissected, TNM clinical staging between the two groups ( Z=-0.570, -0.434, χ2 =0.926, 0.851, 1.655, Z=-0.579, χ2=1.193, Z=-1.134, P>0.05). There were significant differences in the tumor N staging and the number of positive lymph node between the two groups ( Z=-2.167, -2.283, P<0.05). (4) Operative situations of patients with colorectal cancer: all the 97 colorectal cancer patients received successfully laparoscopic radical colectomy or proctectomy, without intraoperative complications or conversion to laparotomy. Cases with radical colectomy or proctectomy (surgical methods), operation time, volume of intraoperative blood loss were 7, 12, 132 minutes(97 minutes, 156 minutes), 20 mL(10 mL, 50 mL) in patients of the glasses-free 3D colorectal cancer group, and 40, 38, 124 minutes(110 minutes, 159 minutes), 25 mL(15 mL, 65 mL) in patients of the polarized glasses 3D colorectal cancer group, with no significant difference between the two groups ( χ2 =1.276, Z=-0.141, -0.863, P>0.05). (5) Postoperative recovery of patients with colorectal cancer: the time to first flatus, time to initial semi-fluid diet intake, duration of postoperative hospital stay were 2 days(1 days, 3 days), 5 days(5 days, 6 days), 8 days(7 days, 10 days) in patients of the glasses-free 3D colorectal cancer group, and 2 days(1 days, 3 days), 5 days(4 days, 6 days), 8 days(6 days, 10 days) in patients of the polarized glasses 3D colorectal cancer group, with no significant difference between the two groups ( Z=-0.678, -1.751, -1.674, P>0.05). The complication incidence of the glasses-free 3D colorectal cancer group was 15.8%(3/19), including 1 case with anastomotic leakage after low anterior proctectomy, 1 case with incision infection, 1 case with urinary tract infection. The complication incidence of the polarized glasses 3D colorectal cancer group was 14.1%(11/78), including 3 cases with anastomotic leakage after low anterior proctectomy, 2 cases with intestinal obstruction, 2 cases with urinary tract infection, 2 cases with incision infection, 1 case with anastomotic bleeding, 1 case with pulmonary infection. One of the 3 cases with anastomotic leakage after low anterior proctectomy in the polarized glasses 3D colorectal cancer group was cured after remedial terminal ileostomy. The other patients with complications were cured after symptomatic supportive treatment. There was no significant difference in the complication incidence between the two groups ( χ2=0.035, P>0.05). (6) Postoperative pathological examination results of patients with colorectal cancer: the tumor diameter, cases in stage T1, T2, T3, T4 (tumor T staging), cases with vascular invasion, cases with nerve invasion, cases with tumor nodule, cases in stage N0, N1-N2 (tumor N staging), the number of positive lymph node, the number of lymph node dissected, cases with qualified lymph node dissected, cases in stage Ⅰ, Ⅱ, Ⅲ, Ⅳ (TNM clinical staging) were 5.0 cm(3.0 cm, 6.0 cm), 3, 2, 7, 7, 3, 2, 1, 8, 11, 0(0, 4), 17(14, 23), 18, 2, 3, 12, 2 in patients of the glasses-free 3D colorectal cancer group, and 4.0 cm(3.0 cm, 5.0 cm), 7, 16, 43, 12, 14, 12, 7, 46, 32, 0(0, 1), 16(13, 19), 74, 14, 17, 40, 7 in patients of the polarized glasses 3D colorectal cancer group, with no significant difference between the two groups ( Z=-0.768, -1.135, χ2 =0.049, 0.292, 0.278, 1.762, Z=-0.694, -1.349, χ2=0.001, Z=-1.011, P>0.05). (7) Follow-up: 165 patients received follow-up, with out short-term reoperation or postoperative death in the postoperative 30 days. Conclusion:There is no significant difference in the efficacy between glasses-free 3D laparoscopic surgery and polarized glasses 3D laparoscopic surgery for radical resection of gastrointestinal malignant tumors, of which the clinical value requires further study.

Aging ; Cellular Senescence ; Heterochromatin ; Humans ; Sirtuins ; genetics ; Stem Cells

To establish an animal model of acute-on-chronic liver failure (ACLF) that would replicate the pathological process of ACLF in humans, rats were administered porcine serum (PS) for 11 weeks. Liver fibrosis was determined by pathological and biochemical assessments. The animals then were injected with d-galactosamine (d-gal) and lipopolysaccharide (LPS). The survival times of animals with cirrhosis and ACLF were determined over 48 h. Other animals were killed at 0, 4, 8 and 12 h after administration of d-gal/LPS. Liver injury was assessed by histopathological analysis and biochemical indices, and apoptosis was detected by Western blot and TUNEL analysis. After PS administration for 11 weeks the serum levels of hyaluronic acid and N-procollagen type III peptide increased significantly, and serious fibrosis and cirrhosis was observed at weeks 10 and 11. Cirrhotic rats were injected with d-gal/LPS to induced ACLF; the rate of mortality over 48 h was 80%. ALT and AST levels increased markedly at 4 h, but decreased significantly at 8 and 12 h post-treatment. The total bilirubin, direct bilirubin, and total bile acids levels increased markedly at 8 and 12 h. Clotting times, TNF-and IL-6 levels increased significantly, except for 12 h post-treatment. Apoptosis, inflammation and necrosis were elevated as determined by hematoxylin-eosin staining and TUNEL assays. BCL-2 levels decreased significantly, While BAX levels increased significantly. Cytochromeexpression peaked at 8 h post-d-gal/LPS treatment. In conclusion, an ACLF model induced by PS and d-gal/LPS was established and the underlying mechanisms of ACLF development were explored.

Objective To explore the long-term outcomes and prognostic factors of laparoscopic gastrectomy for stage T4a gastric cancer.Methods The retrospective case-control study was conducted.The clinicopathological data of 224 patients who underwent laparoscopic gastrectomy of gastric cancer and D2 lymph node dissection in the Ruijin Hospital of Shanghai Jiaotong University School of Medicine between February 2004 and December 2014 were collected.Lymph node dissection followed the Japanese Gastric Cancer Treatment Guidelines (13th edition).Anastomotic methods included Billroth Ⅰ,Billroth Ⅱ and Roux-en-Y gastrojejunostomy or esophagojejunostomy.Patients who were diagnosed in stage T4a by postoperative pathological examination underwent 5-fluorouracil chemotherapy.Observation indicators:(1) treatment;(2) postoperative pathological examination;(3) follow-up;(4) prognostic factors analysis.Follow-up using outpatient examination and telephone interview was performed to detect the postoperative tumor recurrence or metastases up to death (end of follow-up) or July 31,2016.Measurement data with normal distribution were represented as x±s and comparison between groups was analyzed using Student-t test.Measurement data with skewed distribution were described as M (Q).Comparisons of count data were analyzed using the chi-square test.The overall and disease-free survival curves,overall and disease-free survival rates were respectively drawn and calculated using the Kaplan-Meier method.The survival analysis was done by the Log-rank method.The univariate analysis was done by the chisquare test,and COX regression model which included affecting factors (P＜0.10) in the univariate analysis was used for the multivariate analysis.Results (1) Treatment:all the 244 patients underwent successful operation,without conversion to open surgery.Surgical method:laparoscopic-assisted distal gastrectomy (4 combined with cholecystectomy,1 with splenectomy and 1 with transverse colectomy) were detected in 125 patients and laparoscopic-assisted total gastrectomy in 99 patients (3 combined with cholecystectomy and 2 with splenectomy).Anastomotic method:Billroth Ⅰ,Billroth Ⅱ and Roux-en-Y gastrojejunostomy or esophago-jejunostomy were respectively applied to 85,29 and 110 patients.Operation time and volume of intraoperative blood loss were (229±50)minutes and (229 ± 146)mL.All patients underwent 6 or 8 cycles 5-fluorouracil chemotherapy.(2)Postoperative pathological examination:numbers of lymph node dissected and positive lymph nodes were 25± 11 per case and 13 (8,25),with R0 resection.Tumor pathological diagnosis of 224 patients:tumor diameter was (4.5±2.3)cm.Tumors in 29,64,122 and 9 patients respectively located in 1/3 proximal stomach,1/3 middle segment of stomach,1/3 distal stomach and involving 2/3 or total stomach.Tumor differentiation:moderate-and high-differentiated tumors and low-and un-differentiated tumors were detected in 82 and 142 patients,respectively.Postoperative N staging:53,46,55 and 70 patients were detected in staging N0,N1,N2 and N3,respectively.Lymph node metastasis rates of 51,58,53 and 62 patients were 0,1％-15％,16％-40％ and ＞40％,respectively.Postoperative staging was T4a staging.(3) Follow-up:212 of 224 patients were followed up for 7-120 months,with a median time of 32 months.Of 212 follow-up patients,118 were survived and 94 died.Of 118 survived patients,13 and 105 were respectively survived with tumors and without tumor.Of 94 deaths,causes of 8 and 86 were respectively non-tumor and tumor-related deaths.The 5-year overall and disease-free survival rates of 224 patients were respectively 47.2％ and 43.6％.(4) Prognostic factors analysis:results of univariate analysis showed that tumor location,tumor diameter,N staging and lymph node metastasis rate were related factors affecting the postoperative 5-year overall and disease-free survival rates of patients undergoing laparoscopic gastrectomy of stage T4a gastric cancer (x2 =6.365,3.740,32.232,48.977,P＜0.10;x2 =9.919,8.818,34.277,45.612,P＜ 0.10).Results of multivariate analysis showed that lymph node metastasis rate was an independent factor affecting the postoperative 5-year overall and disease-free survival rates of patients undergoing laparoscopic gastrectomy of stage T4a gastric cancer (HR =1.828,1.197,95％ confidence interval:1.353-2.469,0.945-1.516,P＜0.05).Postoperative 5-year overall and disease-free survival rates were respectively 72.5％,57.0％,41.6％,23.3％ and 70.0％,53.9％,37.0％,32.4％in staging N0,N1,N2 and N3 patients,with statistically significant differences in different staging (x2 =32.232,34.277,P＜0.05).Conclusion There are good long-term outcomes in laparoscopic gastrectomy for stage T4a gastric cancer,and lymph node metastasis rate is an independent factor affecting postoperative overall and disease-free survival of patients.