0.999). The characteristic masses and detection limits achieved were as follows,as for As,21 pg and 0.13 ?g/L,as for Se,32 pg and 0.33 ?g/L. The recoveries were 96.0%-103.6% for As,98.3%-104.7% for Se and the RSDs were 0.6%-1.7% for As,0.6%-2.8% for Se. Conclusion This method was accurate, simple and sensitive,it is applicable to the determination of trace As and Se in water.

Objective To evaluate the effect of dexmedetomidine on left ventricular function in patients undergoing coronary artery bypass grafting (CABG) by transesophageal echocardiography (TEE).Methods The study was a prospective,randomized and placebo-control clinical trial.Eighty patients undergoing CABG with cardiopulmonary bypass (CPB) were divided into dexmedetomidine group (group D)and control group (group C) by random digits table method with 40 cases each.A loading dose of dexmedetomidine 0.5 μg/kg was injected intravenously 10 min after induction followed by infusion at 0.4 μ g/(kg· h) until the end of operation in group D,while equal volume of normal saline was given in group C.Left ventricular function was assessed by transesophageal echocardiography before the infusion of dexmedetomidine (T1),at the end of the infusion of loading dose (T2),before CPB (T3) and at the end of the operation (T4).Results Compared with those at T1,left ventricular ejection fraction and fractional area change decreased significantly [(58.0 ± 12.0)％,(60.0 ± 9.6)％ vs.(63.0 ± 8.6)％ and (46.0 ± 9.3)％,(48.0 ± 8.4)％ vs.(51.0 ± 6.7)％] (P ＜ 0.05 or ＜ 0.01),E/A ratio increased significantly (1.05 ± 0.27,1.07 ±0.31 vs.0.98 ±0.19)(P ＜0.05 or ＜0.01) and myocardial performance index (MPI) decreased significantly (0.46 ± 0.14,0.45 ± 0.12 vs.0.51 ± 0.14) (P ＜ 0.05) at T2 and T3 in group D,while stroke volume was not significantly changed (P＞ 0.05).Compared with that in group C,E/A ratio and rapid filling fraction in group D was significantly higher [1.06 ± 0.18 vs.0.97 ± 0.18,(62.0 ± 7.1)％ vs.(58.0 ± 7.3)％],and S/D ratio and MPI was significantly lower at T4(1.17 ± 0.21 vs.1.29 ± 0.22,0.43 ± 0.15 vs.0.50 ± 0.15),and there were significant differences (P ＜ 0.05).There was no difference in the parameters indicating left ventricular systolic function (P ＞ 0.05).Conclusions Dexmedetomidine restrains left ventricular systolic function in the patients undergoing CABG,but does not decrease the cardiac output,and improve relaxation dysfunction of left ventricular diastolic function.Global left ventricular function is improved by dexmedetomidine after CABG.

Objective To explore the biological effects of the luteinizing hormone receptor (LHR) and vascular endothelial growth factor (VEGF) on the ovary of mice during peri-implantation. Methods The immunohistochemistry SABC method and image analysis were used to study the distribution and changes of the LHR and VEGF in Kunming mouse( n =28) ovary during estrous,pregnancy of day 1, day 4 and day 6 stage. Results The expression of LHR-immunoreactive substance and that of VEGF-immunoreactive substance had the same distribution and changes. Compared with other groups,the level of LHR-immunoreactive substance and that of VEGF-immunoreactive substance increased highly on the stroma cells around largergrowing follicles in estrous group ( P <0.05). Along with the pregnancy, the positive immunostaining for LHR and VEGF increased gradually on the granulosa lutein cells, and reached the highest level on day 6 of pregnancy. Positive immunostaining for LHR or VEGF on some endothelia and blood cells were observed in day 1 of pregnancy or estrous group respectively. Form day 1 of pregnancy, the theca cells had positive immunostaining for LHR. Conclusion The expression of LHR and VEGF is closely related with the process of follicle growing, ovulation and corpus luteum formation.

Objective To evaluate the effect of sevoflurane anesthesia on left ventricular synchroni?zation in patients undergoing coronary artery bypass grafting ( CABG ) . Methods Twenty?six patients of both sexes, aged 45-75 yr, with body mass index of 19-30 kg∕m2 and body surface area 1.4-2.0 m2 , of American Society of Anesthesiologists physical status Ⅱ or Ⅲ and New York Heart Association class ⅡorⅢ, undergoing elective CABG with cardiopulmonary bypass, were divided into 2 groups using a random number table: control group ( group C, n=11) and sevoflurane group ( group S, n=15) . After induction of general anesthesia, the patients were endotracheally intubated and mechanically ventilated. Anesthesia was maintained with iv infusion of propofol 4-6 mg·kg-1 ·h-1 , remifentanil 0. 2-0. 3 μg·kg-1 ·min-1 and cisatracurium 0.10-0.15 mg·kg-1·h-1, and intermittent iv boluses of fentanyl 0.5 μg∕kg, and bis?pectral index value was maintained at 40-60. In group S, sevoflurane ( end?tidal concentration: 2.05% for 45-49 yr, 1.80% for 50-59 yr, 1.60% for 60-75 yr) was inhaled for 30 min starting from 15 min after termination of cardiopulmonary bypass, followed by 30 min washout. The parameters of cardiac function
were monitored using transesophageal echocardiography. After induction and before sternotomy, immediate?ly before sevoflurane inhalation, at 30 min of sevoflurane inhalation, and at 30 min of washout, heart rate, mean arterial pressure, central venous pressure, pulmonary artery occlusion pressure, cardiac output, left ventricular ejection fraction, standardized standard deviation of time to peak systolic longitudinal strain of R?R interval ( Tssl?SD) of 17 left ventricular segment, and standardized standard deviation of time to peak systolic circumferential strain of R?R interval ( Tssc?SD) of 16 left ventricular segment were recorded. Re?sults Cardiac output and left ventricular ejection fraction were within in the normal ranges in the two groups. Compared with group C, heart rate was significantly decreased at 30 min of sevoflurane inhalation and 30 min of washout, and mean arterial pressure, cardiac output and left ventricular ejection fraction were significantly decreased at 30 min of sevoflurane inhalation in group S (P<0.05 or 0.01). There were no significant differences in standardized Tssl?SD and standardized Tssc?SD between group S and group C ( P>0.05) . Conclusion Sevoflurane anesthesia has no marked effect on the left ventricular synchronization in patients undergoing CABG.

Objective To determine if the cardiac index (CI) measured by transesophageal echocardiography (TEE) through the mitral valve (MV) agrees with that measured by transesophageal echocardiography through the ascending aorta (AA).Methods Sixteen ASA Ⅱ or Ⅲ patients (NYHA Ⅱ or Ⅲ),aged 18-70 kg,weighing 46-72 kg,undergoing mitral valve replacement under cardiopulmonary bypass (CPB),were studied.Total intravenous anesthesia was used for induction and maintenance of anesthesia.After tracheal intubation,the TEE probe was placed in the esophagus.CI was measured by transesophageal echocardiography through the MV (CIMV)and AA (CIAA) at 15,30 and 60 min after termination of CPB and recorded.All the data were compared by Bland-Altman analysis.Results CIMV values were significantly lower at each time point than CIAA values (P ＜0.01).The results of Bland-Altman comparison:CIMV 1.29-5.52 L· min-1 · m-2,mean was (2.6 ± 0.9)L·min-1·m-2,and CIAA 2.7-8.8 L·min-1·m-2,mean was (4.9± 1.7) L·min-1 ·m-2,bias was-2.3 L·min-1 ·m-2,and limit of agreement was-5.62-1.03 L· min-1 · m-2 resulting in r =-0.577,P ＜ 0.01.Conclusion CI values obtained through the MV agrees well with that measured through the AA using TEE in patients undergoing mitral valve replacement,but CIAA values are significantly higher than CIMV values,there is a large difference between them for clinical use,and both methods for CI measurement cannot replace each other.

Tumor cells leads to enhanced glucose uptake and the conversion of a larger fraction of pyruvate into lactate even under the circumstance of abundant oxygen. This phenomenon of aerobic glycolysis is known as the Warburg effect. Lactic acid, as an important tool for tumor cells to modify the tumor microenvironment, promotes the process of tumor invasion and metastasis, and contributes to tumor development by inducing and recruiting immunosuppression-related cells and molecules. Lactic acid could efflux out of the cancer cells via the monocarboxylate transporters to prevent intracellular acidification. Lactate can inhibit the cytolytic activity of T cells and natural killer (NK) cells, promoting the differentiation of tolerogenic interleukin 10 (IL-10)-producing dendritic cells. Moreover, the lactate-derived lactylation of histone lysine residues can promote macrophage polarization toward the M2-like phenotype, suppressing the immune response within the tumor microenvironment. In this review, we discuss the role of lactate as an immunosuppressor molecule that contributes to tumor evasion from the aspects of lactic acid metabolism and its effect on immune cells. And we explore the possibility of targeting potential targets in lactate metabolism for tumor treatment. At last, we proposed a tumor immunotherapy strategy by inhibiting the pathway of aerobic glycolysis and proteins associated with the production and transport of lactic acid.

BACKGROUNDMedical consortium is a specific vertical integration model of regional medical resources. To improve medical resources utilization and control the health insurance costs by fee-for-service plans (FFS), capitation fee and diagnosis-related groups (DRGs), it is important to explore the attitudes of doctors towards the different health insurance payment in the medical consortium in Shanghai.

METHODSA questionnaire survey was carried out randomly on 50 doctors respectively in 3 different levels medical institutes.

RESULTSThe statistical results showed that 90% of doctors in tertiary hospitals had the tendency towards FFS, whereas 78% in secondary hospitals towards DRGs and 84% in community health centers towards capitation fee.

CONCLUSIONSThere are some obvious differences on doctors' attitudes towards health insurance payment in 3 different levels hospitals. Thus, it is feasible that health insurance payment should be supposed to the doctors' attitudes using the bundled payments along with the third-party payment as a supervisor within consortium.

To observe the effects of ultrasound-guided stellate ganglion block (SGB) on cerebral oxygen metabolism and postoperative cognitive dysfunction (POCD) of elderly patients, we collected 80 elderly patients undergoing selective coronary artery bypass graft under cardiopulmonary bypass. The Mini Mental State Examination (MMSE) was applied to test the cognitive function. The SjvO2, Da-jvO2 and CEO2 were used for the analysis of the cerebral oxygen metabolism. We found that POCD was related to disequilibrium of cerebral oxygen metabolism. Ultrasound-guided SGB before surgery reduced the incidence of POCD because of the improvement of cerebral oxygen metabolism.
Aged ; Autonomic Nerve Block ; Cardiopulmonary Bypass ; Cognition Disorders ; prevention & control ; Coronary Artery Bypass ; Humans ; Neuropsychological Tests ; Oxygen Consumption ; Postoperative Complications ; Stellate Ganglion ; diagnostic imaging ; Ultrasonography

Objective To analyze the sensitivity and specificity of several volume parameters regarding volume responsiveness.The studied volume parameters include pulmonary artery obstruc-tion pressure (PAOP),central venous pressure (CVP),right ventricular end-diastolic volume (RV-EDV)measured by Swan-Ganz pulmonary artery catheter and left ventricular end-diastolic area (LVEDA),inferior vena cava diameter (IVC)measured by transesophageal echocardiography (TEE). Methods Twelve patients with ASA Ⅱ or Ⅲ,scheduled for coronary artery bypass grafting were studied.After anesthesia induction,the TEE probe was put into the esophagus and Swan-Ganz cathe-ter was placed in right internal jugular venous.Measurements were made at the time before cutting the skin (T0 ),20 min after divorcing from cardiopulmonary bypass or finishing vascular anastomosis in off-pump surgery(T1 ),10 min after rapid infusion (T2 )and 30 min after rapid infusion (T3 ),re-spectively.Results The values of PAOP,IVC,LVEDA,COLVOT at time T2 increased significantly compared to those at time T1 (P <0.01).No obvious correlation (r=-0.298 5、r=-0.091 8、r=-0.243 6)was observed between △CVP、△PAOP、△RVEDV and △COLVOT (the difference between T2 and T1 );Meanwhile,△IVC and △LVEDA were well correlated to △COLVOT (r= 0.445 0、r=0.612 0).Using more than 1 5% change of COLVOT after volume expansion as definition of positive re-sponse,the areas under the receiver operating characteristic curves of CVP,PAOP,RVEDV,IVC and LVEDA were 0.389 (95% CI 0.035-0.743 ),0.458 (95% CI 0.109-0.807 ),0.333 (95% CI 0-0.671 ), 0.903 (95% CI 0.701-1.000 ) and 0.889 (95% CI 0.661-1.000 ), respectively. Conclusion PAOP,IVC,LVEDA,CO are more sensitive to the change of volume;while CVP and RVEDV have weak responses to volume changes.This indicates that IVC and RVEDA have more ad-vantage to estimate cardiac output increase and guide volume therapy.

Objective To evaluate the changes in early left ventricular myocardial diastolic function after cardiopulmonary bypass (CPB) in the patients undergoing mitral valve replacement.Methods Twenty patients of both sexes,aged 40-70 yr,of ASA physical status Ⅱ or Ⅲ (NYHA Ⅱ or Ⅲ),with left ventricular ejection fraction (LVEF) ≥ 45 ％,scheduled for elective mitral valve replacement with CPB,were enrolled in the study.Global and regional left ventricular diastolic function was measured by using TEE.After splitting of sternum and at 30 and 90 min after termination of CPB,HR,mean arterial pressure,central venous pressure,cardiac index,LVEF,early diastolic transmitral velocity (E),early diastolic tissue velocity (Ea),right ventricular early myocardial velocity (Em) and right ventricular late myocardial velocity (Am).E/Ea and Em/Am ratios were calculated.Results There was no significant difference in the parameters of hemodynamics and left ventricular diastolic function at each time point before and after CPB.LVEF was greater than 50％ and E/Ea ratio was greater than 20 at each time point in the patients.Conclusion There is no further damage to the early left ventricular myocardial diastolic function after CPB in the patients undergoing mitral valve replacement.