TiO2-SnO2 composite nanocrystalline was prepared by the low temperature hydrothermal method. A new film-type ozone sensor was developed by using TiO2-SnO2 composite nanocrystallines transferred onto an alumina ceramic tube with Au electrodes by dip-coating method. The crystalline phase and microstructure of TiO2-SnO2 nanocrystallines were characterized by X-ray diffraction ( XRD) , field emission scanning electron microscope ( FE-SEM) , energy dispersive X-ray analysis ( EDAX) and ultraviolet-visible spectrometry ( UV-Vis) . The ozone sensitive mechanism and photoelectrochemical properties of TiO2-SnO2 nanocrystallines were analyzed by using ultraviolet-visible spectrometry and electrochemical method. These characteristic tests of ozone sensor were carried out on the traits of sensitive performance, dynamic response, interference and stability under ultraviolet-visible illumination by the XEDWS-60 A type multifunction analyzer in gas sensor static test system. the conclusion demonstrates that when the ozone sensor based on TiO2-SnO2 composite nanocrystalline ( molar ratio of Ti and Sn is 6 ) was under conditions of 40% relative humidity and 25 ℃operating temperature, when ozone concentration was increased from 0. 1 to 1. 8 μg/L, the best linearity of ozone sensor upon ultraviolet illumination and visible illumination were 97 . 5% and 78 . 5%, the dynamic response time was 2 s and 9 s, the recovery time was 5. 5 s and 15 s. This kind of sensor showed good anti-disturbance to the gases, such as CO, NOx , formaldehyde, acetone, butanol and methanol. The response value of ozone sensor was attenuated about 4 . 7%, when ozone sensor was applied continually on the automobile about 12 months, and its normal time was 8. 5 months.

Objective To investigate the effects of bone mesenchymal stem cells (BMSCs)transplantation on the neurological function recovery of injured spinal cord and the underlying mechanism.Methods Rats were subjected to contusive spinal cord injury by using NYU spinal cord contusive impactor system ( NYC lmpactor).Seven days after spinal cord injury,the transplantation of BMSCs ( BMSCs group) or injection of PBS ( PBS group) was performed around the epicenter of injured spinal cord in rats.Basso-Beattie-Bresnahan (BBB) score was used to evaluate the function of spinal cord.The cavity volume of the injured spinal cord was measured and the axons in the injury center of spinal cord were examined under transmission electron microscopy.The BMSCs of the green fluorescent protein (GFP)transgenic rats were used to trace the transplanted cells and the survivor of BMSCs in the injured spinal cord and their differentiation into neural cells were observed.A mini-channel implantation model was employed to further investigate the role of BMSCs transplantation on the axonal regeneration.Results The BMSCs group showed a higher BBB score and a smaller lesion volume as compared with the PBS group.Transmission electron microscopy examination displayed that the number of axons in the BMSCs group was far more than that in the PBS group.A great number of BMSCs-GFP were founded around the center of the injured spinal cord at 4 weeks after BMSCs transplantation.lmmunohistochemistry showed that the implanted BMSCs-GFP did not express the surface marker of neurons,astrocytes and oligodendrocytes.In the mini-channel implantation model,NF-positive nerve fibers grew into the BMSCs-seeded channel,while there were no nerve fibers in the channel without seeding of BMSCs.Conclusions The BMSCs transplantation for the injured spinal cord promotes its functional recovery,and the related mechanism is in correlation with BMSCs transplantation inducing axonal regeneration.

OBJECTIVETo assess the possibility of using arterial pressure waveform or pulse oximetry plethysmographic waveform variation to estimate the pulmonary arterial wedge pressure (PAWP).

METHODSFourteen American Society of Anesthesiologists grade I - II patients aged 33 - 69 years and weighing 62.0 +/- 9.5 kg scheduled for elective abdominal tumor surgery were studied. Their hemoglobin exceeded 120 g/L and hematocrit exceeded 35 percent. Pre-operative acute hypervolemic hemodilution was applied immediately after general anesthestic induction and tracheal intubation. PAWP, systolic pressure variation (SPV), delta down (dDown), SPV(plet), dDown(plet) and other hemodynamic parameters were measured and recorded when total fluid volume (crystalloid and colloid) infused reached 10 ml/kg and 20 ml/kg and again at the end of the operation. Central venous pressure was maintained at 10 - 12 mm Hg during operation. Systolic blood pressure at the end of Valsalva maneuver (airway pressure was kept at 22 mm Hg) and the systolic pressure before the Valsalva manoeuvre during apnea were used to calculate arterial pressure ratio (APR).

RESULTSAPR, SPV, dDown, SPV(plet) and dDown(plet) all correlated well with PAWP (r = 0.717, -0.695, -0.680, -0.522 and -0.624 respectively, P < 0.01). There was a closer linear correlation between APR and PAWP than between the other parameters. The regression equation was PAWP (mm Hg) = 0.207 x APR (%) - 0.382.

CONCLUSIONDuring positive pressure mechanical ventilation, APR, SPV, dDown, SPV(plet) and dDown(plet) can be used to estimate PAWP effectively.

Adult ; Aged ; Blood Pressure Determination ; methods ; Humans ; Middle Aged ; Oximetry ; Plethysmography ; Positive-Pressure Respiration ; Pulmonary Wedge Pressure

Objective To evaluate the efficacy and safety of domestic palonosetron hydrochlo-ride injection on its prevention of postoperative nausea and vomiting.Methods A multi-centered,ran-domized,double-blinded and placebo-controlled clinical trial was carried out.A total of 281 patients were enrolled,with 141 of patients in study group and 140 of patients in control group respectively. 0.075 mg of intravenous palonosetron hydrochloride injection was delivered in the study group before anesthesia induction.The drug was substituted by 1.5 ml of NS in the control group.All anesthesia inductions were conducted by the intravenous injection of propofol,fentanyl and rocuronium,and were maintained with sevoflurane and fentanyl.Complete remission rate and treatment failure cut-off time of vomiting were evaluated at 0-6 h,6-72 h,0-72 h postoperatively.Results In the study group CR% 0-6 h,6-72 h and 0-72 h were 107 (75.89%),104 (73.76%)and 92 (65.25%),the control group was 81 (57.86%),70 (50%)and 62 (42.86%),CR% of the study group was significantly higher than that of the control group (P <0.01).Insignificant statistical difference but significant clin-ical difference exists in their treatment failure cut-off time,386.5 min and 300.0 min,respectively be-tween the groups.Conclusion Domestic palonosetron hydrochloride injection is safe and effective in the prevention of postoperative nausea and vomiting.