Objective:To analyze the differences in clinicopathological features of colon cancers and survival between patients with right- versus left-sided colon cancers.Methods:This was a retrospective cohort study. Information on patients with colon cancer from January 2016 to August 2020 was collected from the prospective registry database at Peking Union Medical College Hospital . Primary tumors located in the cecum, ascending colon, and proximal two‐thirds of the transverse colon were defined as right-sided colon cancers (RCCs), whereas primary tumors located in the distal third of the transverse colon, descending colon, or sigmoid colon were defined as left‐sided colon cancers (LCCs). Clinicopathological features were compared using the χ 2 test or Mann‐Whitney U test. Survival was estimated by Kaplan‐Meier curves and the log‐rank test. Factors that differed significantly between the two groups were identified by multivariate survival analyses performed with the Cox proportional hazards function. One propensity score matching was performed to eliminate the effects of confounding factors. Results:The study cohort comprised 856 patients, with TNM Stage I disease, 391 (45.7%) with Stage II, and 336 (39.3%) with Stage III, including 442 (51.6%) with LCC and 414 (48.4%) with RCC and 129 (15.1%). Defective mismatch repair (dMMR) was identified in 139 patients (16.2%). Compared with RCC, the proportion of men (274/442 [62.0%] vs. 224/414 [54.1%], χ 2=5.462, P=0.019), body mass index (24.2 [21.9, 26.6] kg/m 2 vs. 23.2 [21.3, 25.5] kg/m 2, U=78,789.0, P<0.001), and well/moderately differentiated cancer (412/442 [93.2%] vs. 344/414 [83.1%], χ 2=22.266, P<0.001) were higher in the LCC than the RCC group. In contrast, the proportion of dMMR (40/442 [9.0%] vs. 99/414 [23.9%], χ 2=34.721, P<0.001) and combined vascular invasion (106/442[24.0%] vs. 125/414[30.2%], χ 2=4.186, P=0.041) were lower in the LCC than RCC group. The median follow‐up time for all patients was 48 (range 33, 59) months. The log‐rank test revealed no significant differences in disease-free survival (DFS) ( P=0.668) or overall survival (OS) ( P=0.828) between patients with LCC versus RCC. Cox proportional hazards model showed that dMMR was significantly associated with a longer DFS (HR=0.419, 95%CI: 0.204?0.862, P=0.018), whereas a higher proportion of T3‐4 (HR=2.178, 95%CI: 1.089?4.359, P=0.028), N+ (HR=2.126, 95%CI: 1.443?3.133, P<0.001), and perineural invasion (HR=1.835, 95%CI: 1.115?3.020, P=0.017) were associated with poor DFS. Tumor location was not associated with DFS or OS (all P>0.05). Subsequent analysis showed that RCC patients with dMMR had longer DFS than did RCC patients with pMMR (HR=0.338, 95%CI: 0.146?0.786, P=0.012). However, the difference in OS between the two groups was not statistically significant (HR=0.340, 95%CI:0.103?1.119, P=0.076). After propensity score matching for independent risk factors for DFS, the log‐rank test revealed no significant differences in DFS ( P=0.343) or OS ( P=0.658) between patients with LCC versus RCC, whereas patient with dMMR had better DFS ( P=0.047) and OS ( P=0.040) than did patients with pMMR. Conclusions:Tumor location is associated with differences in clinicopathological features; however, this has no impact on survival. dMMR status is significantly associated with longer survival: this association may be stronger in RCC patients.

Objective:To analyze the differences in clinicopathological features of colon cancers and survival between patients with right- versus left-sided colon cancers.Methods:This was a retrospective cohort study. Information on patients with colon cancer from January 2016 to August 2020 was collected from the prospective registry database at Peking Union Medical College Hospital . Primary tumors located in the cecum, ascending colon, and proximal two‐thirds of the transverse colon were defined as right-sided colon cancers (RCCs), whereas primary tumors located in the distal third of the transverse colon, descending colon, or sigmoid colon were defined as left‐sided colon cancers (LCCs). Clinicopathological features were compared using the χ 2 test or Mann‐Whitney U test. Survival was estimated by Kaplan‐Meier curves and the log‐rank test. Factors that differed significantly between the two groups were identified by multivariate survival analyses performed with the Cox proportional hazards function. One propensity score matching was performed to eliminate the effects of confounding factors. Results:The study cohort comprised 856 patients, with TNM Stage I disease, 391 (45.7%) with Stage II, and 336 (39.3%) with Stage III, including 442 (51.6%) with LCC and 414 (48.4%) with RCC and 129 (15.1%). Defective mismatch repair (dMMR) was identified in 139 patients (16.2%). Compared with RCC, the proportion of men (274/442 [62.0%] vs. 224/414 [54.1%], χ 2=5.462, P=0.019), body mass index (24.2 [21.9, 26.6] kg/m 2 vs. 23.2 [21.3, 25.5] kg/m 2, U=78,789.0, P<0.001), and well/moderately differentiated cancer (412/442 [93.2%] vs. 344/414 [83.1%], χ 2=22.266, P<0.001) were higher in the LCC than the RCC group. In contrast, the proportion of dMMR (40/442 [9.0%] vs. 99/414 [23.9%], χ 2=34.721, P<0.001) and combined vascular invasion (106/442[24.0%] vs. 125/414[30.2%], χ 2=4.186, P=0.041) were lower in the LCC than RCC group. The median follow‐up time for all patients was 48 (range 33, 59) months. The log‐rank test revealed no significant differences in disease-free survival (DFS) ( P=0.668) or overall survival (OS) ( P=0.828) between patients with LCC versus RCC. Cox proportional hazards model showed that dMMR was significantly associated with a longer DFS (HR=0.419, 95%CI: 0.204?0.862, P=0.018), whereas a higher proportion of T3‐4 (HR=2.178, 95%CI: 1.089?4.359, P=0.028), N+ (HR=2.126, 95%CI: 1.443?3.133, P<0.001), and perineural invasion (HR=1.835, 95%CI: 1.115?3.020, P=0.017) were associated with poor DFS. Tumor location was not associated with DFS or OS (all P>0.05). Subsequent analysis showed that RCC patients with dMMR had longer DFS than did RCC patients with pMMR (HR=0.338, 95%CI: 0.146?0.786, P=0.012). However, the difference in OS between the two groups was not statistically significant (HR=0.340, 95%CI:0.103?1.119, P=0.076). After propensity score matching for independent risk factors for DFS, the log‐rank test revealed no significant differences in DFS ( P=0.343) or OS ( P=0.658) between patients with LCC versus RCC, whereas patient with dMMR had better DFS ( P=0.047) and OS ( P=0.040) than did patients with pMMR. Conclusions:Tumor location is associated with differences in clinicopathological features; however, this has no impact on survival. dMMR status is significantly associated with longer survival: this association may be stronger in RCC patients.

Objective:To investigate the interactive effect of mismatch repair (MMR) protein status and adverse clinicopathological features on prognosis of stage Ⅰ-Ⅲ colon cancer.Methods:The retrospective cohort study was conducted. The clinicopathological data of 1 650 patients with colon cancer of stage Ⅰ-Ⅲ who were admitted to 7 hospitals in China from January 2016 to December 2017 were collected. There were 963 males and 687 females, aged 62(53,71)years. Patients were classified as 230 cases of MMR deficiency (dMMR) and 1 420 cases of MMR proficiency (pMMR) based on their MMR protein status. Observation indicators: (1) comparison of clinicopathological characteristics between patients of different MMR protein status; (2) analysis of factors affecting the survival outcomes of patients of dMMR; (3) analysis of factors affecting the survival outcomes of patients of pMMR; (4) interaction analysis of MMR and adverse clinicopathological features on survival outcomes. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was conducted using the independent t test. Measurement data with skewed distribution were represented as M( Q1, Q3), and comparison between groups was conducted using the Mann-Whitney U test. Count data were described as absolute numbers, and comparison between groups was conducted using the chi-square test or Fisher exact probability. Comparison of ordinal data was conducted using the Mann-Whitney U test. The random forest interpolation method was used for missing values in data interpolation. Univariate analysis was conducted using the COX proportional risk regression model, and multivariate analysis was conducted using the COX stepwise regression with forward method. The coefficient of multiplication interaction effect was obtained using the interaction term coefficient of COX proportional risk regression model. Evaluation of additive interaction effects was conducted using the relative excess risk due to interaction ( RERI). Results:(1) Comparison of clinicopathological characteristics between patients of different MMR protein status. There were significant differences in age, T staging, the number of lymph node harvest, the number of lymph node harvest <12, high grade tumor between patients of dMMR and pMMR ( P<0.05). (2) Analysis of factors affecting the survival outcomes of patients of dMMR. Results of multivariate analysis showed that T staging, N staging, the number of lymph node harvest <12 were independent factors affecting the disease-free survival (DFS) of colon cancer patients of dMMR ( hazard ratio=3.548, 2.589, 6.702, 95% confidence interval as 1.460-8.620, 1.064-6.301, 1.886-23.813, P<0.05). Age and N staging were independent factors affecting the overall survival (OS) of colon cancer patients of dMMR ( hazard ratio=1.073, 10.684, 95% confidence interval as 1.021-1.126, 2.311-49.404, P<0.05). (3) Analysis of factors affecting the survival outcomes of patients of pMMR. Results of multivariate analysis showed that age, T staging, N staging, vascular tumor thrombus were independent factors affecting the DFS of colon cancer patients of pMMR ( hazard ratio=1.018, 2.214, 2.598, 1.549, 95% confidence interval as 1.006-1.030, 1.618-3.030, 1.921-3.513, 1.118-2.147, P<0.05). Age, T staging, N staging, high grade tumor were independent factors affecting the OS of colon cancer patients of pMMR ( hazard ratio=1.036, 2.080, 2.591, 1.615, 95% confidence interval as 1.020-1.052, 1.407-3.075, 1.791-3.748, 1.114-2.341, P<0.05). (4) Interaction analysis of MMR and adverse clinicopathological features on survival outcomes. Results of interaction analysis showed that the multiplication interaction effect between the number of lymph node harvest <12 and MMR protein status was significant on DFS of colon cancer patients ( hazard ratio=3.923, 95% confidence interval as 1.057-14.555, P<0.05). The additive interaction effects between age and MMR protein status, between high grade tumor and MMR protein status were significant on OS of colon cancer patients ( RERI=-0.033, -1.304, 95% confidence interval as -0.049 to -0.018, -2.462 to -0.146). Conclusions:There is an interaction between the MMR protein status and the adverse clinicopathological features (the number of lymph node harvest <12, high grade tumor) on prognosis of colon cancer patients of stage Ⅰ-Ⅲ. In patients of dMMR, the number of lymph node harvest <12 has a stronger predictive effect on poor prognosis. In patients of pMMR, the high grade tumor has a stronger predictive effect on poor prognosis.

Objective:Upper gastrointestinal bleeding (UGIB) is a common gastrointestinal disease in the emergency department. Identifying low-risk patients suitable for outpatient treatment is the focus of clinical and research. A simple predictive model was developed to identify patients with UGIB who could safely avoid hospitalization, thus providing a feasible basis for triage by emergency physicians.Methods:A retrospective cohort study was conducted on patients with UGIB treated at Zhongda Hospital Southeast University from January 2015 to December 2020. Baseline demographic data and clinical parameters at the initial presentation were recorded. Multivariate logistic regression model was performed to identify predictors of safe discharge.Results:Six hundred and twelve patients (45.9%) were not safely discharged. There were significant differences in age, Charlson comorbidity index, systolic blood pressure, pulse rate, hemoglobin, albumin, blood urea nitrogen, creatinine and international normalized ratio between the safe discharge group and the non-safe discharge group ( P<0.05). Using multivariate logistic regression analysis, a total of 7 variables were included in the clinical prediction model of UGIB risk stratification: Charlson comorbidity index > 2, systolic blood pressure < 90 mmHg, hemoglobin < 10 g/dL, blood urea nitrogen ≥6.5 mmol/L, albumin <30 g/L, pulse ≥100 beats/min and international normalized ratio ≥1.5. The sensitivity, specificity, positive predictive value, and negative predictive value for predicting unsafe discharge were 98.37%, 24.10%, 52.3%, and 94.6%, respectively, with the best cutoff value ≥1. The area under the receiver operating characteristic (AUROC) curve was 0.822, which was significantly higher than Glasgow Blatchford score (GBS) 0.786 (95% CI: 0.752-0.820, P< 0.01) and AIMS65 0.676 (95% CI: 0.638-0.714, P< 0.01). Conclusions:The predictive model has a reliable predictive value, which can provide references for emergency medical staff to triage patients with UGIB, thereby reducing medical expenses and having certain social and economic benefits.

Objective To investigate the mechanism of action of integrin α4 (ITGA4) in liver fibrosis based on the anti-liver fibrosis effect of sticky sugar amino acid (SSAA) in rats. Methods A rat model of liver fibrosis was induced by intraperitoneal injection of CCl 4 , and then colchicine and low-, middle-, and high-dose SSAA were used for intervention, with blank control group and SSAA group as control. After 12 weeks of experimental intervention, serum and liver samples were collected to measure the serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), and HE staining and Sirius Red staining were used to observe the pathological conditions of liver tissue; quantitative real-time PCR was used to measure the transcriptional level of ITGA4, integrin β1 (ITGB1), transforming growth factor-β1 (TGFβ1), alpha-smooth muscle actin (α-SMA), and TIMP2 in liver tissue; Western blot was used to measure the relative protein expression levels of ITGA4, ITGB1, TGFβ1, α-SMA, MMP2, TIMP1, and TIMP2; immunohistochemistry was used to observe the protein expression of TGFβ1 and α-SMA. A one-way analysis of variance was used for comparison of continuous data between multiple groups, and the least significant difference t -test was used for comparison between two groups. Results There were significant increases in AST and ALT in the CCl 4 model group, and intervention with colchicine or low-, middle-, and high-dose SSAA reduced the levels of AST and ALT, with a significant difference between the CCl 4 model group and the other groups (all P < 0.05). HE staining and Sirius Red staining showed disordered structure of hepatic lobules and an increase in collagen fibers in the CCl 4 model group, and the structure of hepatic lobules was improved after intervention with colchicine or low-, middle-, and high-dose SSAA. The CCl 4 model group had significantly higher transcriptional levels of ITGA4, TGFβ1, α-SMA, and TIMP2 than the other groups, and there were significant reductions in the transcriptional levels of each factor after intervention with colchicine or SSAA, with a significant difference between the CCl 4 model group and the other groups (all P < 0.05). The CCl 4 model group had significantly higher protein expression levels of ITGA4, TGFβ1, α-SMA, TIMP2, and TIMP1 and a significantly lower protein expression level of MMP2 than the other groups, and intervention with colchicine or SSAA inhibited the expression of ITGA4, TGFβ1, α-SMA, TIMP2, and TIMP1 and promoted the expression of MMP2. Immunohistochemistry showed that the CCl 4 model group had significantly higher expression levels of TGFβ1 and α-SMA than the other groups, which was inhibited by intervention with colchicine or SSAA. The high-dose SSAA group had the most significant effect in reducing aminotransferases, improving lobular structure, and inhibiting the protein expression of liver fibrosis factors. Conclusion The high expression of ITGA4 in the liver is associated with the development of liver fibrosis, which is consistent with the increases in the expression of TGFβ1 and α-SMA. Inhibiting the expression of ITGA4 can provide more therapeutic targets for liver fibrosis and expand the anti-liver fibrosis mechanism of SSAA.

Objective To determine the diagnosis value of urinary albumin(mAlb)/creatinine(Ucre) ratio in random urine from patients with early diabetic nephropathy.Methods From March 2015 to December 2016,98 case with simple diabetes and early diabetic nephropathy in Ankang Hospital of Traditional Chinese Medicine were selected,including 47 cases with simple diabetes and 51 cases with early diabetic nephropathy.And 60 healthy people were selected as control group.The mAlb and mAlb/Ucre ratios in morning urine,postprandial urine and random urine were detected for three times in three days,and the resluts were calculated and analyzed.Results In early diabetic nephropathy group,the mAlb concentration varied during different time periods,mAlb in morning urine [(60.5 ± 27.1)mg/L] and postprandial urine [(60.7 ± 26.7)mg/L] were significantly increased compared with that in random urine [(40.9 ± 25.1) mg/L] (F =9.551,P =0.000).The MAlb/Ucre ratios were stable in morning urine,postprandial urine and random urine of each period (P ＞ 0.05).The positive rate of mAlb/Ucre ratio was sharply higher than mAlb alone in random urine (90.2％ vs.62.7％).No statistically significant difference showed in positive rates of mAlb/Ucre ratio in subjects from different groups(the positive rate of morning urine specimen was 92.2％;postprandial urine 88.2％;random urine 90.2％,P ＞ 0.05).Conclusion Positive rate of mAlb/Ucre ratio changed slightly during different test periods,and is superior to mAlb alone in clinic application.Additionally,the positive rate of mAlb/Ucre ratio in random urine could serve as an indicator in early screening of early diabetic nephropathy.

Objective To evaluate the effect of remifentanil preconditioning ( RP ) on intestinal is?chemia?reperfusion ( I∕R) injury in rats and its relationship with opioid receptors. Methods Seventy?two Sprague?Dawley rats, aged 6-7 weeks, weighing 250-280 g, were randomly divided to 9 groups ( n=8 each): sham operation group (S), intestinal I∕R group (group I∕R), RP group, different opioid receptor antagonists groups (N, BNI and CTOP groups), and opioid receptor antagonists + RP groups (N+RP, BNI+RP and CTOP+RP groups) . Intestinal I∕R was produced by clamping the superior mesenteric artery for 1 h followed by 2 h reperfusion in all the groups except group S. RP was induced by 3 cycles of 5 min infusion of remifentanil 0?2 μg·kg-1 ·min -1 followed by 5 min infusion of normal saline before ischemia. Naltrindole (δ?receptor antagonist, 5 mg∕kg) , nor?binaltorphimine (κ?receptor antagonist, 5 mg∕kg) and CTOP (μ?receptor antagonist, 1 mg∕kg) were administered before RP. At 2 h of reperfusion, blood sam?ples were collected from the cardiac apex for determination of serum diamine oxidase ( DAO) activity. Intes? tinal tissues were then removed for microscopic examination. Intestinal damage was assessed and scored ac?cording to Chiu. Apoptosis in intestinal mucosal epithelial cells was detected using TUNEL assay, and ap?optosis index was calculated. The expression of activated caspase?3 in intestinal mucosal epithelial cells was measured by Western blot. Results Compared with group S, the serum DAO activity, Chiu′s score, and apoptosis index were significantly increased, and the expression of activated caspase?3 was up?regulated in I∕R and RP groups ( P<0?05) . Compared with group I∕R, the serum DAO activity, Chiu′s score, and ap?optosis index were significantly decreased, and the expression of activated caspase?3 was down?regulated in RP, BNI+RP and CTOP groups (P<0?05), and no significant change was found in the parameters men?tioned above in N, N+RP, BNI and CTOP+RP groups (P>0?05). Compared with group RP, the serum DAO activity, Chiu′s score, and apoptosis index were significantly increased, and the expression of activa?ted caspase?3 was up?regulated in N+RP and CTOP+RP groups ( P<0?05) , and no significant change was found in the parameters mentioned above in group BNI+RP ( P>0?05) . Conclusion RP can mitigate in?testinal I∕R injury in rats, and the mechanism is related to the anti?apoptotic effect mediated by activation ofδ?and μ?opioid receptors, but not κ?opioid receptors.

Objective To investigate the effects of remote limb ischemic preconditioning (RLIP) on the lung injury in patients undergoing abdominal aortic aneurysm repair.Methods Sixty-two ASA Ⅱ or Ⅲ patients of both sexes,aged 54-72 yr,with body mass index 21-36 kg/m2,undergoing elective abdominal aortic aneurysm repair,were randomly divided to 2 groups ( n =31 each):control group (group C) and RLIP group.RLIP consisted of two 5-min cycles of left upper limb ischemia induced by a blood pressure cuff placed on the left upper arm and inflated to 200 mm Hg,with an intervening 5 min of reperfusion,during which time the cuff was deflated.RLIP was performed after anesthesia induction and before the start of surgery.Arterial and venous blood samples were taken at 10 min after intubation (T0),and 30 min and 4,8,12 and 24 h after aortic unclamping (T1-5) for blood gas analysis and determination of the concentrations of serum interleukin (IL)-6,tumor necrosis factor (TNF)-α,and plasma malondialdehyde (MDA) and superoxide dismutase (SOD) activity.The alveolar-arterial oxygen pressure difference (PA-aO2 ) and respiratory index (RI) were calculated.The peak airway pressure (Ppeak),plat airway pressure (Pplat) and positive end expiratory pressure (PEEP) were recorded at the same time points mentioned above to calculate dynamic lung compliance (Cd) and static lung compliance (Cs).The incidence of hypoxemia,extubation time and duration of stay in intensive care unit (IGU) were also recorded.Results Compared with group C,PA-aO2,RI and the concentration of IL-6 were significantly decreased at T3-5,Cs,Cd and SOD activity were significantly increased at T2-5,and the concentrations of TNF-α and MDA were significantly decreased at T2-5 in group RLIP ( P ＜ 0.05).Compared with group C,the incidence of hypoxemia was significantly decreased,and extubation time and duration of stay in ICU were significantly shortened in group RLIP ( P ＜ 0.05).Conclusion RLIP can reduce the lung injury through inhibition of the inflammatory response and lipid peroxidation in patients undergoing abdominal aortic aneurysm repair.

Objective To investigate the effects of intestinal ischemia-reperfusion (I/R) on the brain in rats. Methods Sixty-four healthy male SD rats weighing 250-300 g were randomly allocated to one of 2 groups (n = 32 each): sham operation group (S) and intestinal I/R group (I/R). Intestinal I/R was produced by occlusion of superior mesenteric artery (SMA) for 90 min followed by reperfusion. Eight animals were sacrificed at each of the following time points: 2, 6, 12 and 24 h of reperfusion (T1-4) in each group. After a median sternotomyblood samples were taken from left ventricle for measurement of plasma TNF-α and IL-6 (by ELISA). Intestine and brain tissue was harvested for microscopic examination and detection of apoptosis ( by TUNEL). The cognitive function was tested using Morris water maze at 24 h. Results No abnormality was found in intestine and brain tissue in group S. Intestinal damage and neurodegeneration were detected in group I/R. Intestinal I/R significantly increased cerebral apoptosis in group I/R compared with group S. Plasma TNF-a and IL-6 concentrations were significantly higher at T1-4 in group I/R than in group S. The escape latency and swimming distance were significantly increased, while the number of crossing the platform was decreased in group I/R compared with group S. There was no significant difference in the swimming speed between the 2 groups. Conclusion Intestinal I/R can induce brain injury and lead to cognitive dysfunction. I/R-induced release of inflammatory mediators and neuronal apoptosis are involved in the underlying mechanism.

Objective To investigate the changes in skin microcirculatory perfusion during induction of general anesthesia and the effects oftwo fluid therapy regimens in patients undergoing abdominal surgery.Methods Thirty-six ASA Ⅰ or Ⅱ patients aged 18-64 yr scheduled for elective major abdominal surgery were randomized to receive either 6% hydroxyetlayl starch(130/0.4)7 ml/kg(HES group,n=18)or lactated Ringer's solution 7 ml/kg(RL group,n=18)for compensatory intravascular volultne expansion(CVE)before tracheal intubation.Meanwhile both groups received continuous intravenous infusion of RL at a of 8 ml·kg~(-1)·h~(-1).Tracheal intubation was performed at 40 min after the onset of infusion.Anesthesia was maintained with with sevoflurane,remifentanil and rocuronium.Operation was started at 20 min after tracheal intubation.The microcirculatory perfusion was measured on forehead skin by using Doppler perfusion imaging system(LDPI)PI)at the onset of fluid infusion(T_0,baseline),the end of endotracheal intubation(T_1)and the onset of skin incision(T_2).Rwsults The MAP,HR,blood gases and body temperature were within the normal during the experiment and there was no significant difference between the 2 groups.The skin microcirculatory perfusion and CVP at T_1 were significantly higher in group HES than in group RL(P<0.05 or 0.01).Compared with the baseline value at T_0,the skin microcirculatory perfusion at T_1 was significantly increased in group HES(P<0.01),but there was no significant change in the skin microcirculatory perfusion at T_1 in group RL(P>0.05),the skin microcirculatory perfusion at T_2 was singificantly decreased in both groups(P<0.01),and CVP and PaO_2/FiO_2 at T_(1.2) were significantly increased,while Hb at T_(1.2) was significantly decreased in both groups(P<0.05).The skin microcirculatory perfusion in both groups was significantly lower at T_2 than at T_1(P<0.01).Conclusion The infusion of 6% HES 130/0.4 can improve the skin microcirculatory perfusion and the effect is better than that of RL during induction of general anesthesia in patients seheduled for abdominal surgery.