Objective To investigate the effects of nerve growth factor (NGF) on the expression of 67-kDa laminin receptor (67LR) in human bile duct carcinoma QBC939 cells, and study the possible mechanism of perineural invasion and metastasis of bile duct carcinoma. Methods ( 1 ) The expression of a high-affinity receptor for NGF, TrkA, was detected by immunofluorescence staining. ( 2 ) QBC393 cells were pretreated by β-NGF at different concentrations ( 1, 10, 100,200 μg/L), and then the mRNA and protein expressions of 67LR were examined by Real-Time PCR and Western blot assay. QBC939 cells were divided into control group and β-NGF (1, 10, 100,200 μg/L) groups. (3) The ideal concentration of β-NGF was selected according to the results of previous tests, and then the mRNA and protein expressions of 67LR were re-examined by adding specific TrkA inhibitor K252a at different concentrations ( 100,200,300 nmol/L). QBC939 cells were divided into control group, β-NGF 100 μg/L group and K252a ( 100,200,300 nmol/L) groups. All data were analyzed by one-way analysis of variance or LSD-test. Results (1) A strong expression of TrkA was detected in the membrane of QBC939 cells. (2) The mRNA and protein expressions of 67LR in QBC939 cells were 0.35 ± 0.06 and 0. 32 ± 0.05 in the control group, 0.38 ±0.14 and 0.50 ±0.09 in the β-NGF 1 μg/L group, 0.62 ±0.14 and 0. 69 ±0. 13 in β-NGF 10 μg/L group, 0.90 ± 0.08 and 0.93 ± 0.07 in the β-NGF 100 μg/L group, and 0. 70 ± 0. 10 and 0. 76 ±0.07 in the β-NGF 200 μg/L group, there were significant differences among the five groups (F = 22. 4, 14. 6,P ＜0.05). The mRNA and protein expressions of 67LR in the β-NGF 100 μg/L group were significantly higher than those in the control group ( t = 19. 0, 21.0, P ＜ 0. 05 ). (3) The mRNA and protein expressions of 67LR in the QBC939 cells were 0.35 ±0.10 and 0.41 ±0.10 in the control group, 0. 88 ±0. 14 and 0.84 ±0.10 in the β-NGF 100 μg/L group, 0.80±0.08 and 0.76 ±0.04 in the K252a 100 nmol/L group, 0.67 ±0.12 and 0.61 ± 0.09 in the K252a 200 nmol/L group, and 0. 43 ± 0.07 and 0. 50 ± 0. 12 in the K252a 300 nmol/L group, there were significant differences among the five groups ( F = 14. 1, 8. 9, P ＜ 0.05 ). There were no significant differences in the mRNA and protein expressions of 67LR between the K252a 300 nmol/L group and the control group (t =1.02, 0. 85, P＞0.05). Conclusion In bile duct carcinoma cells, NGF enhances the expression of 67LR by combining with TrkA, which might be the mechanism of NGF mediating perineural invasion of bile duct carcinoma.

Objective To investigate the effects of weightlessness on the apoptosis of hepatocytes in rats.Methods Eighty-four adult male Wistar rats were randomly divided into weightlessness group and control group according to the random number table.Tail-suspension was used to simulate the weightlessness model.Six rats were sacrificed in each group at the end of day 1-7.Hepatocyte apoptosis and p53 expression were detected by TUNEL assay and immunohistochemistry PV-6001,respectively.All data were analyzed by variance analysis.Results An increase of apoptosis index and up-regulated expression of p53 were detected in weightlessness group.The level of apoptotic index Was significantly higher in weightlessness group than in control group from day 1 to day 5(F=77.608,P<0.05),and the apoptotic indexes of the 2 groups were close at day 6 and day 7.The p53 proteins with positive expression were mainly detected in the nucleus.The level of positive expression of p53 in liver tissue in weightlessness group was higher than that in control group at the early stage(F=113.063,P<0.05).Few hepatocytes with positive expression were detected in control group and weightlessness group at a later stage.Conclusion There is a close relationship between hepatocyte apoptosis,changes of P53 expression and stress response and tolerance to weightlessness.

Objective To investigate the correlation between α1-adrenergic receptor and the pathological behavior of cholangiocarcinoma, and the effects of norepinephrine (NE) on the proliferation of cholangiocarcinoma cell line QBC939. Methods Thirty-six samples of cholangiocarcinoma were resected in Southwest Hospital from August 2002 to March 2008. The expression of α1-adrenergic receptor in the 36 samples of cholangiocarcinoma tissue and 4 samples of normal bile duct tissue were detected by SABC technique. The proliferation of cholangio-carcinoma cell line QBC939 was detected after processing the cells with NE, phentolamine and prazosin. All the data were analyzed by chi-square test. Results The high positive expression rate of α1-adrenergic receptor was 68% (17/25) in patients with lymph node metastasis, which was significantly higher than 9% (1/11) in patients without lymph node metastasis (χ2=10.604, P<0.05). The high positive expression rate of α1-adrenergic receptor was 85% (11/13) in patients with middle and low positioned cholangiocarcinoma, which was significantly higher than 30% (7/23) in patients with hilar cholangiocarcinoma (χ2=9.753, P<0.05). NE promoted the proliferation of cholangiocarcinoma cell line QBC939 by stimulating the expression of α1-adrenergic receptor, and in a concentration-dependent manner. The proliferative effect was weakened as time passed by, and it was eliminated by phentolamine and prazosin. Conclusions The expression of α1-adrenergic receptor is diverse due to lymph node metastasis and the location of the tumor, α1-adrenergic receptor with high expression may play an important role in the proliferation and metastasis of cholangiocarcinoma.

Objective To investigate the clinical significance of multiple tumor markers in the early diagnosis of cholangiocarcinoma.Methods 165 patients with histopathologically confirmed cholangiocarcinoma and 25 patients with gallstone canceration were enrolled in this study.36 patients with gallstones and 46 patients with bile duct stenosis were enrolled as controls.The determinations of multiple tumor markers,including carcinoembryonic antigen (CEA),CA125,CA153,CA242,CA19-9,alpha-fIetoprotein (AFP) and Ferritin,of all subjects and the imageological determinations of all the patients with cholangiocarcinoma and with gallstone canceration were analysed retrospectively.Comparisons between the groups were performed using the likelihood ratio test of the Chi-square test.Results CA19-9 had the highest sensitivity and specificity (83.6％ and 96.3％ respectively) for cholangiocarcinoma,and CA242 had a high sensitivity for gallstone canceration though it was not so sensitive in cholangiocarcinoma.Multiple tumor markers increased the sensitivity and specificity in the early diagnosis of cholangiocarcinoma.Compared with imageological determinations,multiple tumor markers had a higher sensitivity for the early diagnosis of cholangiocarcinoma with a tumor mass ＜1 cm.Conclusion Multiple tumor markers have important clinical values in the early diagnosis of cholangiocarcinoma.

Comparing the cardiovascular disease in onion-growing region with those in non-onion-growing region, we found that, the people in these two regions are similar in their living standard, economic income and dietary habits and customs. The death rates caused by cardiovascular disease in these two regions were 0.57‰ and 1.67‰ respectively. There were markedly different incidences (p

Objective:To explore the relationship between work connectivity behavior after-hours, self-regulatory fatigue and work engagement of nurses, so as to provide reference for developing strategies to improve nurses′work engagement.Methods:This was a cross-sectional survey study. A total of 661 nurses from 10 hospitals in Shandong Province were selected as subjects by convenience sampling method from June to August 2022. The Work Connectivity Behavior After-hours Scale, Self-Regulatory Fatigue Scale and Work Engagement Scale were used to measure the work connectivity behavior after-hours, self-regulatory fatigue level and work engagement level. A structural equation model was constructed to evaluate the mediating effect of self-regulatory fatigue on work connectivity behavior after-hours and work engagement.Results:The scores of work connectivity behavior after-hours, self-regulatory fatigue and work engagement of nurses were (37.66 ± 7.05), (42.98 ± 10.55) and (34.29 ± 6.58) points, respectively. The total effect of work connectivity behavior after hours on work engagement was -0.336 6. The work connectivity behavior after-hours was positively correlated with self-regulatory fatigue ( r = 0.423, P<0.01) and work engagement was negatively correlated with work connectivity behavior after-hours and self-regulatory fatigue ( r = -0.361, -0.479, both P<0.01). Self-regulatory fatigue had a partial mediating effect on work connectivity behavior after-hours and work engagement, accounting for 46.61% of the total effect. Conclusions:Self-regulatory fatigue has a mediating effect on the relationship between nurses′ work connectivity behavior after-hours and work engagement. Nursing managers should reduce the degree of self-regulatory fatigue of nurses by preventing their work connectivity behavior after-hours, so as to improve the work involvement level of nurses.

Objective To assess the local treatment efficacy of percutaneous radiofrequency ablation(PRFA) in combination with percutaneous ethanol injection(PEI) therapy protocol for liver metastases in patients with colorectal cancer.Methods From February 2000 to February 2004, total of 61 liver metastatic lesions(1.5～7.8 cm) from 37 colorectal cancer patients were ablated by using RF-2000 generator and 10-needle LeVeen electrode percutaneously guided by B-ultrasound.Tumors larger than 2.5 cm in diameter were treated by multiple overlapping radiofrequency ablations encompassing the entire lesion as well as a rim of normal liver tissue(approximately 1.0 cm).PEI was performed additionally.The Chiba needle and Quadra-Fuse multi-pronged injection needle were used for tumors ranged 1～2 cm and for those larger than 3 cm respectively.Results The procedures were performed successfully in all patients.The post-PRFA/PEI complication rate was 5.4%.The follow-up rate was 97.3%(36/37).Thirteen patients achieved a complete response(CR),and 21 achieved a partial response(PR).The effective rate(CR+PR) was 94.4%.The patients' survival rates were 97.2% at 1 year,75.0% at 2 years,and 52.8% at 3 years respectively.Conclusion The results of this study suggest that the treatment protocol of PRFA in combination with PEI was an effective mini-invasive local ablation therapy,which was part of the comprehensive management of the colorectal liver metastases.

OBJECTIVE: To explore the influencing factors of occupational stress from occupational hazards in employees of a power grid enterprise. METHODS: A total of 972 employees from 3 substations and 1 power dispatch center of a power grid enterprise were selected as research subjects by the cluster sampling method. The Chinese version of the Job Content Questionnaire was used to evaluate the occupational stress using the job demand control(JDC) model. The influence of occupational hazards on occupational stress was analyzed. RESULTS: The median, the 25 th and 75 th percentile scores [M(P_(25), P_(75))] of the 972 research subjects on job demand, job control, and social support dimensions of JDC model occupational stress were 14(12, 15), 25(23, 26), 24(23, 24), respectively. The M(P_(25), P_(75)) of the demand/control(D/C) ratio was 0.99(0.89, 1.13). The incidence of occupational stress was 48.4%(470/972) by the JDC model. The job demand dimension scores, D/C ratios, and incidence of occupational stress by JDC model were higher in employees exposed to electromagnetic radiation, high temperature, high altitude, and visual display terminal(VDT) than in those employees not exposed to the above factors(all P<0.05). The results of multivariate logistic regression analysis showed that the risk of occupational stress increased in those employees exposed to high temperature, high altitude and VDT(all P<0.05) after excluding the influence of confounding factors such as age, length of service, monthly income and exercise. The odds ratio and 95% confidence intervals were 1.91(1.43-2.54) and 1.67(1.26-2.21), respectively. CONCLUSION: The level of occupational stress among employees in power grid enterprise is relatively high by JDC model. High-temperature, high-altitude and VDT operation are the main risk factors of occupational stress by JDC model.