This study was performed for the output of nitrous oxide (N_2O) after N_2O cessation. The breathing bag with the volume of 3000 ml served as the simulator lung,and 5 patients, ASA grade Ⅰ,aged 18-48 years scheduled for elective surgery,acted as the clinical subiects. After the equilibration of end-expiratory N_2O concentration of 50% was developed,the N_2O administration was cut off,then was expelled with oxygen flow rate at 3L/min or 6L/min. The inspiration-expiration N_2O concentration difference of simulator or patient lung (SC_(I-E) N_2O or PC_(I-E) N_2O)was recorded with an infra-red gas analyser. The N_2O dilution induced by the anesthesia circuit volume and the functional residual capacity, was similar to that by simulator lung,so the clinical output of N_2O in one minute was calculated as followed: N_2O output=(PC_(I-E) N_2O-SC_(I-E) N_2O)?minute volume of ventilation. The results showed that in the first minute after N_2O termination,there was no N_2O output,but from the second to the tenth minute the N_2O output increased gradually and was kept at the high level,additionally,the levels of N_2O output at the oxygen flow rate of 6L/min were higher than those at 3L/min in the corresponding times, respectively. It is suggested that following the withdrawal of 1:1 N_2O-O_2 anesthesia ,the N_2O output is related to the oxygen flow rate,and there is not the occurance of diffusion hypoxia.

To observe the influence of different concentrations of sevoflurane on blood brain barrier permeability in rats, thirty adult male SD rats were randomly divided into three groups: control group (without general anesthetics), 1 MAC sevoflurane and 1.5 MAC sevoflurane groups (maintaining end expiratory concentration to 2.2% and 3.3% respectively for 1 hour). Before the end of the experiment, 2% Evans′ blue dye (EB, 3ml/kg) was intravenously injected. The range and areas of EB staining on the surface and standardized serial coronal section of the brain were assessed. The brain was also observed under the light microscope and electron microscope. The results indicated that sevoflurane at both concentrations did not increase the permeability of BBB to EB and lanthanum, and there were no significant changes in morphological features of central nervous system after inhalation of sevoflurane.

Objective To observe the effects of propofol or thiopental on the changes of blood brain barrier (BBB) permeability in focal cerebral ischemia Methods Focal cerebral ischemia model was induced with occluding the middle cerebral artery (MCA) Sixty adult male SD rats were divided randomly into 5 groups: control group(group MC): without any anesthetics; propofol pretreated group (group MP1) or thiopental pretreated group (group MT1): intravenous bolus of propofol 20mg/kg or thiopental 40mg/kg, followed by intravenous infusion of propofol or thiopental at rate of 50 60 mg?kg 1 ?h 1 or 100 120 mg?kg 1 ?h 1 ,respectively ,to achieve and maintain the EEG burst suppression 30 min before MCA occlusion until the beginning of reperfusion; propofol therapy group (group MP2) or thiopental therapy group (group MT2): from the beginning to the end of the reperfusion , propofol or thiopental was administered at the same dose as group MP1 or group MT1; Blood pressure, P ET CO 2, ECG and EEG were monitored throughout the experiment Rectal temperature was maintained between 37 5℃ and 38 5℃ At the end of the experiment, after intravenous bolus of 2% evans blue dye(EB) 3ml/kg, the brain was taken out to check out the extends and areas of EB staining on the surface and standardized serial coronal sections of the brain ,under the optical microscope and electromicroscope Results 1 Both propofol groups did not alleviate BBB permeability changes and cerebral damage 2 Cerebral injury was most slightly in group MT1 3 BBB permeability and brain injury in group MT2 were slighter than those in group MC and MP1, MP2 Conclusions Thiopental at the dose maintaining EEG burst suppressioncan can reduce the brain injury induced with ischemia and reperfusion, with the better protective effects following the prophylactic administration Propofol at that dose can not improve the cerebral ischemic reperfusion injury

Objective To evaluate the influence of propofol on the permeability of the blood brain barrier(BBB) in adult and aged rats.Methods Aged or adult rats were given two doses propofol in 1 hour,respectively.BBB permeability was examined by optical microscopy,electromicroscopy and Evans blue(EB) staining.Results (1)Brain EB staining was not seen in aged or adult groups that at either dose of propofol.(2)In all groups of aged and adult rats,the structure of the blood vessels was normal and lanthanum was not seen outside the blood vessels.(3)There were no significant changes in the central nervous system under microscope or electromicroscope in any groups.Conclusions Propofol at the two doses has no significant effect on BBB permeability or on the central nervous system morphology in aged and adult rats.

Objective:To investigate the role of epidermal growth factor receptor (EGFR)in the regulation of B[a]P-induced silent information regulator 1 (SIRT1 ) activation in the human bronchial epithelial cells (BEAS-2B),and to clarify the relationship between EGFR/SIRT1 signal transduction pathway and the occurrence and development lung cancer.Methods:The prediction analysis of transcriptional factor binding sites of SIRT1 was performed by MOTIF SearchTM software.The primary cultivated BEAS-2B cells were divided into control group (without B[a]P exposure)and B[a]P groups (the cells were exposed to B[a]P for 6,12,24,48 h).RT-PCR and Western blotting method were carried out to detect the EGFR mRNA and protein expression levels.The BEAS-2B cells transfected with SIRT1 promotor luciferase reporter gene plasmid were treated with human epidermal growth factor (hEGF)and Genistein (tyrosine protein kinase inhibitor)for 24 h,the morphology of BEAS-2B cells was observed by inverted microscope, and luciferase reporter assay was used to test the SIRT1 transcriptional activity.The human lung tissue biopsies were acquired and the immunohistochemical analysis was used to determine the EGFR protein expression level.Results:The transcriptional factor binding sites of SIRT1 contained EGF, 2Fe-2S and vWF.Compared with control group,the expression levels of EGFR mRNA in B [a]P groups were increased in a time-dependent manner,and reached the peak at 12 h (P < 0.05);the EGFR protein expression levels were also increased (P <0.05).The SIRT1 luciferase activity in hEGF group was increased compared with control group (P <0.05);when hEGF and B[a]P worked together,the SIRT1 luciferase activity was increased even further (P <0.001). The cells showed arrangement and morphologic changes gradually when the B[a]P concentration was above 30 μmol · L-1. Genistein (30 μmol · L-1 )inhibited the increase of SIRT1 luciferase activity induced by B [a]P ,and there was significant difference compared with control group (P <0.05).The immunohistochemistry results showed that EGFR expression level in lung cancer tissue was higher than that in normal lung tissue (P < 0.001).Conclusion:EGFR can regulate the B [a]P-induced SIRT1 expression in BEAS-2B cells,and to cause lung chronic inflammation;EGFR/SIRT1 signal transduction pathway may play a role in the occurrence and development of lung cancer.

Objective:To analyze the application of Cho peak value and color doppler ultrasound blood flow score in the early diagnosis of breast cancer, and to evaluate the relationship between Cho peak value, blood flow score, TNM stage and prognosis quality.Methods:A total of 82 patients with breast cyst admitted from Jan. 2015 and Dec. 2019 were selected as subjects for the study. ROC curve was used to compare the ability of color doppler flow score and functional magnetic resonance imaging (fmri) in the diagnosis of breast cancer when used alone or in combination. Logistic regression model was used to analyze the factors affecting the prognosis quality and TNM staging of patients.Results:The breast cancer group’s Cho value and blood flow signal score were significantly higher than the benign breast lesion group, and the difference was statistically significant (Cho value: t=43.977, P<0.001; blood flow signal score: t=22.071, P<0.001) ; The sensitivity, specificity and AUC of MRS combined with Doppler ultrasound for differential diagnosis of breast cancer are significantly higher than MRS or Doppler ultrasound alone, and the difference was statistically significant (sensitivity: χ2=4.514, P=0.016; specificity: χ2=4.858, P=0.013; AUC: Z=5.251, P<0.001) ; Cho value of patients with good prognosis group ( t=3.984, P<0.001) and blood flow signal score ( t=4.213, P<0.001) were significantly lower than those in the poor prognosis group; Cho value ( t=3.612, P<0.001) and blood flow signal score ( t=3.835, P<0.001) of TNM stage 0-Ⅱ patients were significantly lower than those of stage Ⅲ-Ⅳ group, the difference was statistically significant; the Cho value of the MRS scan and the patient’s prognosis quality ( OR=1.837, 95% CI=1.210-2.788, P=0.004) and TNM stage ( OR=1.818, 95% CI=1.224~2.702, P=0.003) was significantly positively correlated. The blood flow signal and the patient’s prognostic quality ( OR=1.906, 95% CI=1.105~3.287, P=0.020) and TNM stages ( OR=1.799, 95% CI=1.232-2.626, P=0.002) also showed a significantly positive correlation. Conclusion:The combination of Cho peak value and color doppler ultrasound blood flow score can significantly improve the early diagnosis efficiency of breast cancer, and Cho peak value and blood flow score are independent factors affecting TNM staging and prognosis.