ABSTRACT
Objective To evaluate the feasibility and effectiveness of four closure techniques ,large incision with plastic distal at‐tachment and clip with suction ,1 .1 cm small incision with plastic distal attachment and clip with suction in natural orifice translu‐minal endoscopic surgery(NOTES) .Methods Forty‐one ex vivo porcine stomachs were involved in this research .According to the size of incision and different methods of incision closure ,all ex vivo porcine stomachs were divided into four groups .Group A in‐volved 8 ex vivo porcine stomachs ,their size of incision were 1 .2-2 .0 cm ,and their incisions were closured by a clip closure direct‐ly ;group B involved 10 ex vivo porcine stomachs ,their size of incision were 1 .2-2 .0 cm ,and their incisions were closed by plastic end attachment with suction and clip enclosure technique;group C involved 10 ex vivo porcine stomachs ,their size of incision were smaller than 1 .1 cm ,and their incisions were by a clip closure directly ;group D involved 13 ex vivo porcine stomachs ,their size of incision were smaller than 1 .1 cm ,and closured by plastic end attachment with suction and clip enclosure technique .Stomach leaks were evaluated by leaking studies after the procedure .Results In group A ,1 incision was closed successfully ,7 incisions were clo‐sured unsuccessfully ;in group B ,2 incisions were closed successfully ,8 incisions were closed unsuccessfully ;in group C ,2 incisions were closed successfully ,8 incisions were closured unsuccessfully ;in group D ,11 incisions were closed successfully ,2 incisions were Closured unsuccessfully .Fisher′s exact test showed that group D was significantly related to the success of incision closure .The were significant differences between group A and D ,group B and group D(P<0 .05) .Conclusion Small incision(smaller than 1 cm) and plastic end attachment with suction and clip enclosure technique are optimal in NOTES procedure in this ex vivo porcine stomachs study .
ABSTRACT
Objective The optimal access for natural orifice transluminal endoscopic surgery is still uncertain .This study was designed to compare the practicability and maneuverability of transgastric ,transunmbilical ,and transrectal approach in abdominal surgery in a canine model .Methods Three dogs were used in this research .Three approach :trangastric ,transunmbilical and tran-srectal approach were carried out for abdominal exploration ,liver biopsy ,bladder biopsy and an attempted cholecystectomy .The ma-neuverability ,endoscopic image ,performer′s perception ,and spatial orientation were evaluated .Results The maneuverability of trangastric ,and transrectal approach NOTES were better than transunmbilical NOTES .Abdominal exploration ,live biopsy ,and bladder biopsy were completed successfully .The cholecystectomy was failed because of poor exposure and difficulty of separating the around tissure .Conclusion The optimal approach for upper abdomen NOTES is transrectal route .For lower abdomen NOTES , the trangastric approach is superior to other accesses .Further study is needed to develop more flexible and precise equipment for NOTES and to evaluate more feasible access approach .
ABSTRACT
Cadmium (Cd) is ubiquitous in the human environment and has toxic effect on soil microbial biomass or its activity, including microbial biomass carbon (C(mic)), dehydrogenase activity (DHA) and basal respiration (BR), etc., C(mic), DHA, BR were used as bioindicators of the toxic effect of Cd in soil. This study was conducted to determine the effects of Cd on soil microbial biomass and its activity in a paddy soil. The inhibition of microbial biomass and its activity by different Cd concentrations was described by the kinetic model (M1) and the sigmoid dose-response model (M2) in order to calculate three ecological doses of Cd: ED(50), ED(10) and ED(5). Results showed that M2 was better fit than M1 for describing the ecological toxicity dose effect of cadmium on soil microbial biomass and its activity in a paddy soil. M2 for ED values (mg/kg soil) of C(mic), DHA, BR best fitted the measured paddy soil bioindicators. M2 showed that all ED values (mg/kg) increased in turn with increased incubation time. ED(50), ED(10) and ED(5) of C(mic) with M2 were increased in turn from 403.2, 141.1, 100.4 to 1000.7, 230.9, 144.8, respectively, after 10 d to 60 d of incubation. ED(50), ED(10) and ED(5) of DHA with M2 increased in turn from 67.6, 6.2, 1.5 to 101.1, 50.9, 41.0, respectively, after 10 d to 60 d of incubation. ED(50), ED(10) and ED(5) of BR with M2 increased in turn from 149.7, 6.5, 1.8 to 156.5, 50.8, 35.5, respectively, after 10 d to 60 d of incubation. So the ecological dose increased in turn with increased incubation time for M2 showed that toxicity of cadmium to soil microbial biomass and its activity was decreased with increased incubation time.