AIM:To determine the rate of use and non-use of prophylactic percutaneous endoscopic gastrostomy(PEG) tubes among patients with head and neck cancer(HNC) patients.METHODS:All patients with HNC undergoing PEG between J...AIM:To determine the rate of use and non-use of prophylactic percutaneous endoscopic gastrostomy(PEG) tubes among patients with head and neck cancer(HNC) patients.METHODS:All patients with HNC undergoing PEG between January 01,2004 and June 30,2006 were identified.Patients(or their next-of-kin) were surveyed by phone and all available medical records and cancer registry data were reviewed.Prophylactic PEG was def ined as placement in the absence of dysphagia and prior to radiation or chemoradiation.Each patient with a prophylactic PEG was assessed for cancer diagnosis,type of therapy,PEG use,and complications related to PEG.RESULTS:One hundred and three patients had PEG tubes placed for HNC.Thirty four patients(33%) could not be contacted for follow-up.Of the 23(22.3%) patients with prophylactic PEG tubes,11/23(47.8%) either never used the PEG or used it for less than 2 wk.No association with PEG use vs non-use was observed for cancer diagnosis,stage,or specific cancer treatment.Non-use or limited use was observed in 3/6(50%) treated with radiation alone vs 8/17(47.1%) treated with chemoradiation(P = 1.0),and 3 of 10(30%) treated with surgery vs 8 of 13(62%) not treated with surgery(P = 0.21).Minor complications were reported in 5/23(21.7%).One(4.3%) major complication was reported.CONCLUSION:There is a high rate of unnecessary PEG placement when done prophylactically in patients with head and neck cancer.展开更多
To improve the utilization efficiency of water the laying length of porous tubes was analyzed. Considering long porous tubes the irrigation uniformity of porous tubes was studied by analyzing the deviation rate of the...To improve the utilization efficiency of water the laying length of porous tubes was analyzed. Considering long porous tubes the irrigation uniformity of porous tubes was studied by analyzing the deviation rate of the working head of porous tubes and through an impact analysis of the deviation ratio of flow rate based on laying length slope pressure head and perforation spacing. Results showed that the deviation ratio of the flow rate could be reduced by decreasing the length of tubes and increasing the slope. The deviation ratio of flow rate was less influenced by pressure head and perforation spacing. A best laid slope resulted in a longer laying length of the porous tubes and they were not constant.展开更多
Pancreatic tuberculosis(TB) is a rare condition,even in immunocompetent hosts.A case is presented of pancreatic TB that mimicked pancreatic head carcinoma in a 40-year-old immunocompetent male patient.The patient was ...Pancreatic tuberculosis(TB) is a rare condition,even in immunocompetent hosts.A case is presented of pancreatic TB that mimicked pancreatic head carcinoma in a 40-year-old immunocompetent male patient.The patient was admitted to our hospital after suffering for nine days from epigastralgia and obstructive jaundice.Computed tomography revealed a pancreatic mass that mimicked a pancreatic head carcinoma.The patient had undergone an operation four months prior for thoracic TB and was undergoing anti-TB therapy.A previous abdominal ultrasound was unremarkable with the exception of gallbladder steroid deposits.The patient underwent surgery due to the progressive discomfort of the upper abdomen and a mass that resembled a pancreatic malignancy.A biopsy of the pancreas and lymph nodes was performed,revealing TB infection.The patient received a cholecystostomy tube and recovered after being administered standard anti-TB therapy for 15 mo.This case is reported to emphasize the rarecontribution of pancreatic TB to pancreatic masses and obstructive jaundice.展开更多
Based on the Navier-Stokes （N-S） equations of incompressible viscous fluids and the standard k-ε turbu- lence model with assumptions of steady state and two dimensional conditions, a simulation of the aerodynamic d...Based on the Navier-Stokes （N-S） equations of incompressible viscous fluids and the standard k-ε turbu- lence model with assumptions of steady state and two dimensional conditions, a simulation of the aerodynamic drag on a maglev train in an evacuated tube was made with ANSYS/FLOTRAN software under different vacuum pressures, blockage ratios, and shapes of train head and tail. The pressure flow fields of the evacuated tube maglev train under different vacuum pressures were analyzed, and then compared under the same blockage ratio condition. The results show that the environmental pressure of 1 000 Pa in the tube is the best to achieve the effect of aerodynamic drag reduction, and there are no obvious differences in the aerodynamic drag reduction among different streamline head shapes. Overall, the blunt-shape tail and the blockage ratio of 0.25 are more efficient for drag reduction of the train at the tube pressure of 1 000 Pa.展开更多
To examine the working principle of vertical tube irrigation, variations in vertical tube emitter discharge and their causes were analyzed in the laboratory experiment. The effects of the pressure head, initial soil w...To examine the working principle of vertical tube irrigation, variations in vertical tube emitter discharge and their causes were analyzed in the laboratory experiment. The effects of the pressure head, initial soil water content, and tube diameter on the emitter discharge of the vertical tube were studied. The results show that quantitative relationship between the time and cumulative infiltration and emitter discharge of the vertical tube is obtained, and R 2 is more than 0.98. Emitter discharge exhibits a positive and negative correlation with the pressure head and soil water content, respectively. Tube dia- meter has a nonsignificant effect on the emitter discharge. Changes of the soil water content around the emitter water outlet are the main causes of emitter discharge variations. In the experiments, the range of vertical tube emitter discharge is 0.056-1.102 L/h. The emitter of vertical tube irrigation automatically adjusts the soil water content and maintains the root zone soil water content within an appropriate range, which achieves continuous irrigation, and further achieves the effect of water-saving.展开更多
文摘AIM:To determine the rate of use and non-use of prophylactic percutaneous endoscopic gastrostomy(PEG) tubes among patients with head and neck cancer(HNC) patients.METHODS:All patients with HNC undergoing PEG between January 01,2004 and June 30,2006 were identified.Patients(or their next-of-kin) were surveyed by phone and all available medical records and cancer registry data were reviewed.Prophylactic PEG was def ined as placement in the absence of dysphagia and prior to radiation or chemoradiation.Each patient with a prophylactic PEG was assessed for cancer diagnosis,type of therapy,PEG use,and complications related to PEG.RESULTS:One hundred and three patients had PEG tubes placed for HNC.Thirty four patients(33%) could not be contacted for follow-up.Of the 23(22.3%) patients with prophylactic PEG tubes,11/23(47.8%) either never used the PEG or used it for less than 2 wk.No association with PEG use vs non-use was observed for cancer diagnosis,stage,or specific cancer treatment.Non-use or limited use was observed in 3/6(50%) treated with radiation alone vs 8/17(47.1%) treated with chemoradiation(P = 1.0),and 3 of 10(30%) treated with surgery vs 8 of 13(62%) not treated with surgery(P = 0.21).Minor complications were reported in 5/23(21.7%).One(4.3%) major complication was reported.CONCLUSION:There is a high rate of unnecessary PEG placement when done prophylactically in patients with head and neck cancer.
基金Sponsored by the National Natural Science Foundation of China(Grant Nos.11362019 and 11562018)
文摘To improve the utilization efficiency of water the laying length of porous tubes was analyzed. Considering long porous tubes the irrigation uniformity of porous tubes was studied by analyzing the deviation rate of the working head of porous tubes and through an impact analysis of the deviation ratio of flow rate based on laying length slope pressure head and perforation spacing. Results showed that the deviation ratio of the flow rate could be reduced by decreasing the length of tubes and increasing the slope. The deviation ratio of flow rate was less influenced by pressure head and perforation spacing. A best laid slope resulted in a longer laying length of the porous tubes and they were not constant.
文摘Pancreatic tuberculosis(TB) is a rare condition,even in immunocompetent hosts.A case is presented of pancreatic TB that mimicked pancreatic head carcinoma in a 40-year-old immunocompetent male patient.The patient was admitted to our hospital after suffering for nine days from epigastralgia and obstructive jaundice.Computed tomography revealed a pancreatic mass that mimicked a pancreatic head carcinoma.The patient had undergone an operation four months prior for thoracic TB and was undergoing anti-TB therapy.A previous abdominal ultrasound was unremarkable with the exception of gallbladder steroid deposits.The patient underwent surgery due to the progressive discomfort of the upper abdomen and a mass that resembled a pancreatic malignancy.A biopsy of the pancreas and lymph nodes was performed,revealing TB infection.The patient received a cholecystostomy tube and recovered after being administered standard anti-TB therapy for 15 mo.This case is reported to emphasize the rarecontribution of pancreatic TB to pancreatic masses and obstructive jaundice.
基金supported by the Program for Changjiang Scholars and Innovative Research Team in University(PCSIRT) of the Ministry of Education of China(IRT0751)the National High Technology Research and Development Program of China (863 program: 2007-AA03Z203)+2 种基金the National Natural Science Foundation of China (Grant Nos. 50588201 and 50872116)the Research Fund for the Doctoral Program of Higher Education of China (SRFDP200806130023)the Fundamental Research Funds for the Central Universities (SWJTU09BR152, SWJTU09ZT24, and SWJTU11CX073)
文摘Based on the Navier-Stokes （N-S） equations of incompressible viscous fluids and the standard k-ε turbu- lence model with assumptions of steady state and two dimensional conditions, a simulation of the aerodynamic drag on a maglev train in an evacuated tube was made with ANSYS/FLOTRAN software under different vacuum pressures, blockage ratios, and shapes of train head and tail. The pressure flow fields of the evacuated tube maglev train under different vacuum pressures were analyzed, and then compared under the same blockage ratio condition. The results show that the environmental pressure of 1 000 Pa in the tube is the best to achieve the effect of aerodynamic drag reduction, and there are no obvious differences in the aerodynamic drag reduction among different streamline head shapes. Overall, the blunt-shape tail and the blockage ratio of 0.25 are more efficient for drag reduction of the train at the tube pressure of 1 000 Pa.
基金National Natural Science Foundation of China (41571222)。
文摘To examine the working principle of vertical tube irrigation, variations in vertical tube emitter discharge and their causes were analyzed in the laboratory experiment. The effects of the pressure head, initial soil water content, and tube diameter on the emitter discharge of the vertical tube were studied. The results show that quantitative relationship between the time and cumulative infiltration and emitter discharge of the vertical tube is obtained, and R 2 is more than 0.98. Emitter discharge exhibits a positive and negative correlation with the pressure head and soil water content, respectively. Tube dia- meter has a nonsignificant effect on the emitter discharge. Changes of the soil water content around the emitter water outlet are the main causes of emitter discharge variations. In the experiments, the range of vertical tube emitter discharge is 0.056-1.102 L/h. The emitter of vertical tube irrigation automatically adjusts the soil water content and maintains the root zone soil water content within an appropriate range, which achieves continuous irrigation, and further achieves the effect of water-saving.
