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Objective To identify risk factors of non-curative resection in superficial esophageal cancer (SEC) after endoscopic submucosal dissection and to evaluate the prognosis. Methods We retrospectively analyzed the data of 207 SEC patients who received ESD. The median follow-up was 48 months. Results The en bloc resection rate was 89.25% (191/214), the complete resection rate was 80.84 % (173/214), the curative resection rate was 70.09% (150/214) and the non-curative resection rate was 29.91% (64/214). The maximum long diameter of specimen was 110 mm. Age, gender, tumor size, lesions performance during surgery and operation time were associated with the non-curative resection (P < 0.05). Female, lesion diameter≥50mm and poorly performed lesions were identified as significant risk factors for non-curative resection. In the non-curative resection group, there was no difference in cancer-free survival and survival between patients who had no additional treatmeat after ESD and those who underwent surgery or radiotherapy. Conclusion For patients with poor general condition who are not willing to undergo surgery or chemoradiotherapy, regular endoscopy seems to be an option.

In order to determine influence of ventilation mode on dust distribution on fully mechanized heading face and explore dust reduction effect under different ventilation modes, the 209 fully mechanized heading face of Longde Coal Mine was taken as research object, and the software of FLUENT was used to simulate distribution of dust in the roadway and dust distribution law and dust reduction effect under combined pumping and pressure ventilation mode. Accuracy of numerical simulation was verified through field measurement. The analysis results show that the dust pollution in the roadway under the forced-in ventilation mode is serious, the area affected by dust is large and settlement is slow; the simulation results are basically the same as the measured dust concentration in the field, which virifies reliability of the numerical simulation results, and furthermore, the rationality of the established mathematical model and its parameter settings is explained; by comparing dust reduction effect of ventilation mode of long-pressure short-pumping and short-pressure long-pumping, the conclusion is got that the ventilation mode of long-pressure short-pumping has the best dust reduction effect when air outlet of the pressure cylinder is 5 m away from the working surface, and the dust concentration can be quickly reduced to below 6 mg/m3.

In order to determine rational borehole spacing of parallel boreholes for gas drainage, a fluid-solid coupling model of gas drainage was established by deducing gas migration equation of coal seam, deformation equation of coal and rock, and coupling equation of seepage field and stress field. According to actual geological conditions of 21219 working face in a mine, variation law of gas pressure and effective drainage radius under influence of drainage superposition effect between parallel boreholes were numerically simulated by COMSOL Multiphysics software, and rational borehole spacing was obtained by combining with effective drainage radius of borehole. The numerical simulation results show that gas pressure of coal body after drainage increases with the increase of borehole spacing. As the distance between coal body and borehole decreases, gas pressure of coal body decreases slowly at first and then decreases rapidly. With the increase of drainage time, gas pressure decreases continuously and effective drainage radius increases. The field application results verify rationality of borehole spacing arrangement.

Coal gangue releases heavy metals and other pollutants through weathering and rain conditions during the natural accumulation process, which causes serious ecological risks to the surrounding soil environment. This study aimed to analyze the content of heavy metals in the soil around a coal gangue dump and to explore the phytotoxic effects induced by the exposure of soil samples to comprehensively assess the ecological risks of the soil around the coal gangue accumulation area. The results showed that the average contents of Cd, Pb, and Zn in the soil around the coal gangue accumulation area exceeded the background values of soil elements in Shanxi Province, and the content of heavy metals in the soil first increased and then decreased with the distance from the coal gangue dump. The enrichment factor results also showed that the pollution of Cd, Pb, and Zn in the soil was serious. The growth of barley seedlings was inhibited after exposure to the soil at different distances from the gangue dump, and some soils could induce the decrease in chlorophyll and the increase in MDA content; the increase in SOD, POD, and GSH activities; the significant decrease in CAT activities; and the decrease in mitotic index (MI) and significant increase in micronucleus rate (MN) in root tip cells. The Pearson correlation coefficient showed that Cr, As, and Zn were significantly positively correlated with the shoot weight, root weight, and micronucleus rate of barley, whereas Cu and Pb were significantly negatively correlated with the chlorophyll and micronucleus rate, respectively.

Coal gangue is a harmful solid waste product of coal mining. When it accumulates for a long time, it becomes harmful to the surroundings. To investigate the adverse effect of coal gangue on the surrounding environment, this study investigated the effects of coal gangue and its downstream village on the growth toxicity and genotoxicity of barley at different dilution concentrations (1：27, 1：9, 1：3, and 1：1) via hydroponic experiments. As a result, low concentration coal gangue showed a slight promotion effect on the growth of roots and shoots of barley, while coal gangue and village soil, which have a high concentration, could seriously inhibit their germination and growth. At the same time, with the increase of the concentration of coal gangue, malondialdehyde (MDA) in barley leaves increased, and chlorophyll (Chl) increased first and then decreased, while the village soil showed a lower toxic effect. In addition, our results showed that higher concentrations of coal gangue and village soil could decrease the mitotic index and increase the micronucleus rate in root tip cells, indicating that the toxicity mechanism of coal gangue to barley may be involved in genotoxicity. These results provide experimental evidence for the ecological risk assessment of the coal gangue and its surrounding environment.

The effects of magnesium sulfate (MgSO4) on sodium currents (Na(+) currents) were studied in freshly dissociated hippocampal CA(1) neurons of rat using the whole-cell patch-clamp technique. The results indicated that MgSO4 caused a concentration-dependent and voltage-dependent decrease in Na(+) currents. The half-inhibitory concentration (IC(50)) was 4.05 mmol/L. This action was frequency-independent. The results also showed that 4 mmol/L MgSO4 shifted the steady state activation curve of Na(+) currents towards positive potential (control V(h)=-55.8+/-6.8 mV, MgSO4 V(h)=-34.2+/-6.2 mV, n=8, P<0.01) without changing the slope factor. However, the steady state inactivation curve was not affected. These results suggest that blockade of Na(+) currents by MgSO4 might be an interpretation for its neuroprotection against damages induced by ischemia and oxygen deprivation.

In the chronic inhalation experiment of sulfur dioxide(SO2), micronuclei(MN) frequencies in the polychromatophilic erythroblasts(PCE) of mouse bone marrow and the frequencies of cells with MN were significantly increased in dose-dependent manner. There was a significant difference between the male and the female animals. The results also showed that SO2 inhibited urethone-induced MN formation. These results furtherly confirm that SO2 inhalation was a clastogenic and genotoxic agent to mammalian cells, and the combined effects of SO2 and other mutagens are complex.

Aim: To study the effect of magnesium sulfate on transient outward K+ current (IA) and delayed rectifier K+ current (IK) in freshly dissociated hippocampal neurons of rats., Methods: The whole-cell patch clamp techniques were used., Results: Magnesium sulfate reversibly reduced the amplitudes of IA and IK in a concentration-dependent and voltage-dependent, but not frequency-dependent manner. Half-blocking concentration (IC50) on IA and IK were 6.30 mmol.L-1 and 7.60 mmol.L-1, respectively. Magnesium sulfate (6 mmol.L-1) affected the activation process of IA and IK. Before and after application of the drug, the half-activation voltages of IA were (7 +/- 6) mV and (-7 +/- 11) mV (n = 10, P < 0.01), and the half-activation voltages of IK were (20 +/- 6) mV and (28 +/- 4) mV (n = 10, P < 0.01), but the slope factors were not changed. In addition, magnesium sulfate (6 mmol.L-1) also affected the inactivation process of IA. Before and after application of the drug, the half-inactivation voltages of IA were (-65 +/- 5) mV and (-89 +/- 6) mV (n = 10, P < 0.01)., Conclusion: Magnesium sulfate inhibited IA and IK in freshly dissociated hippocampal neurons of rats, which might contribute to protect the central neuronal system (CNS) against damages induced by ischemia and oxygen deprivation.

The effect of SO2 derivatives on Na(+) currents was studied in freshly dissociated hippocampal CA1 neurons of rat using the whole-cell patch-clamp technique. The results indicated that SO2 derivatives caused a dose-dependent and voltage-dependent increase in the voltage-activated Na+ currents. The amplitudes of Na(+) currents were increased by 50.59 19.08% and 82.06 18.51% (n=15)by SO2 derivatives at 10 and 100 micromol/L, respectively. The action was frequency-independent. The results also showed that SO2 derivatives did not affect the activation process, but changed the inactivation process significantly. Before and after application of 10 micromol/L SO2 derivatives, the half-inactivation voltage was -69.71+/-4.67 and -53.27+/-4.95 mV (n=10, P<0.01), respectively, but the slope factor was not changed. These results imply that SO2 derivatives have neurotoxic effects and that SO2 pollution is probably related to some diseases of central neuronal system.

Objective: To compare pharmacokinetics of desflurane, sevoflurane, isoflurane and enflurane in general anesthesia., Methods: 40 patients scheduled for abdominal hysterectomy under general anesthesia were randomly divided into desflurane(D), sevoflurane(S), isofluane(I) and enflurane(E) groups. After induction of anesthesia and endotracheal intubation, desired fraction (Fd) of desflurane(6%), sevoflurane(2%), isoflurane (1.15%) and enflurane(1.7%) in oxygen and nitrous oxide(1:2) were inhaled in D, S, I and E groups, respectively. The fractional end tidal alveolar concentration (Fa) was adjusted to 1MAC during the maintenance of anesthsia. Fa and the fractional inspired concentration of inhaled anesthetics (Fi) were monitored continuously. During operation, fentanyl was infused continuously and pancuronium was injected intermittently., Results: After the beginning of inhalational anesthesia, the time required for Fa/Fi = 1:2 and Fa = 1MAC in D and S groups was significantly shorter than that in E and I groups. The rates of Fa/Fi in D and S groups were significantly higher than those in E and I groups during the maintenance of anesthesia, so were those of Fa/Fd. After cessation of inhalational anesthesia, the time required for Fa equaled to 50% of Fa0(the last Fa during stoping administration of the inhalational anesthesia) in D group was significantly faster than that in the other three groups., Conclusions: The rates of desflurane wash-in and wash-out are faster than those of other inhaled anesthetics. The depth of anesthesia is easy to control when desflurane is used in general anesthesia.