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Zinc injection technology (zinc water chemistry, ZWC) was widely applied in pressurized water reactor (PWR) primary circuits to reduce radiation buildup and improve corrosion resistance of structural materials. The simultaneous injection of zinc-aluminium (ZAWC) is a novel implement created to replace part of Zn2+ by Al3+. It was reported ZAWC can improve further corrosion resistance of carbon steels and stainless steels. However, ZAWC sometimes showed even negative effects on Nickel-alloys. In this study, mechanism of formation of oxide film on metals was investigated. The reactions of Fe2+ Ni2+ in oxide films replaced by Zn2+, or Fe3+ replaced by Al3+ in ZAWC were analysed. The thermodynamic data and solubility of mixed oxides (ZnFe2O4, ZnCr2O4, and ZnAl2O4), the products of replace reactions, were calculated. According to the Gibbs free energy difference between products and reactants, ΔGθ(T) values of the formation reaction of ZnFe2O4, ZnCr2O4, and ZnAl2O4 are extremely negative. Solubility of ZnAl2O4 is the lowest among mixed oxide products, which implies the oxide film composites of ZnAl2O4 may show a lower corrosion rate. In addition, the preferential formation of NiAl2O4 on Ni-based-alloy, under ZAWC, was discussed based on crystallographic properties of spinel, which was considered as the cause of negative effects of ZAWC on corrosion resistance of Nickel-alloys. This research provides an analytical basis for the study of thermodynamic stability of oxide films under different chemical chemistry and a theoretical basis for improving corrosion resistance of different metals and optimizing the chemical conditions of PWR primary circuit.

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BACKGROUND: Few studies have reported the effects of simultaneous injections of corticosteroid (CS) and hyaluronic acid (HA) on adhesive capsulitis (AC) of the shoulder. This study investigated the synergistic effects of simultaneous intra-articular injections of CS and compared them to those of CS or HA alone. METHOD: Sixty patients with AC were enrolled in this randomized, placebo-controlled trial. The participants were divided into 4 groups: saline, CS, HA, and CS with HA groups. The primary outcome measure was changes in the Shoulder Pain and Disability Index (SPADI) scores at one month. The secondary outcome measures included changes in pain, range of motion, muscle strength, and additional shoulder functional scores at 1 day, 1 week, and 1, 3, and 6 months after injection. RESULTS: After 1 month, changes of the SPADI scores were significantly higher in the CS with HA group (-58.4%) than those in the saline (-7.7%) and HA (-14.4%) groups. The score changed more in the CS with HA group than that in the CS group (-43.7%), but there was no significant difference. In the changes in pain, the CS with HA group showed significantly better and faster effects than the saline and HA groups. In the changes of range of motion, functional scores, the CS with HA group showed better results than the saline and HA groups. CONCLUSION: In the treatment of AC, the simultaneous injection of CS and HA was more effective in improving SPADI scores at one month after injection than a single injection of CS or HA.

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A novel four-channel simultaneous injection effective mixing flow analysis (SIEMA) system has been assembled for successive determination of bilirubin and creatinine in urinary samples. The chemical variables and physical parameters in the flow system were optimized for the enhancement of successive analytical performances. The interferences from urine matrices on the determination of bilirubin and creatinine were eliminated to dilute urine samples. The calibration graphs with the optimum conditions were achieved to be in 0.024-5.0 mg L(-1) for bilirubin and 2-100 mg L(-1) for creatinine. The relative standard deviations (RSDs) at 3 mg L(-1) of bilirubin and at 50 mg L(-1) of creatinine for 11 runs were 1.5 and 1.0%, respectively. The limits of detections (3σ of blank) for bilirubin and creatinine were 7 µg L(-1) and 0.6 mg L(-1), respectively. The sample throughput for stepwise detection was 22 h(-1). The proposed method was applied to the successive determination of bilirubin and creatinine in urine samples.

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A double toxin-double lesion strategy is well-known to generate a rat model of striatonigral degeneration (SND) such as multiple system atrophy-parkinsonian type. However, with this model it is difficult to distinguish SND from Parkinson's disease (PD). In this study, we propose a new rat model of SND, which is generated by simultaneous injection of 6-hydroxydopamine into the medial forebrain bundle and quinolinic acid into the striatum. Stepping tests performed 30 min after intraperitoneal L-dopa administration at 6 weeks post-surgery revealed an L-dopa response in the PD group but not the SND group. Apomorphine-induced rotation tests revealed no rotational bias in the SND group, which persisted for 2 months, but contralateral rotations in the PD group. MicroPET scans revealed glucose hypometabolism and dopamine transporter impairment on the lesioned striatum in the SND group. Tyrosine hydroxylase immunostaining in the SND group revealed that 74.7% of nigral cells on the lesioned side were lost after lesion surgery. These results suggest that the proposed simultaneous double toxin-double lesion method successfully created a rat model of SND that had behavioral outcomes, multitracer microPET evaluation, and histological aspects consistent with SND pathology. This model will be useful for future study of SND.

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A double toxin-double lesion strategy is well-known to generate a rat model of striatonigral degeneration (SND) such as multiple system atrophy-parkinsonian type. However, with this model it is difficult to distinguish SND from Parkinson's disease (PD). In this study, we propose a new rat model of SND, which is generated by simultaneous injection of 6-hydroxydopamine into the medial forebrain bundle and quinolinic acid into the striatum. Stepping tests performed 30 min after intraperitoneal L-dopa administration at 6 weeks post-surgery revealed an L-dopa response in the PD group but not the SND group. Apomorphine-induced rotation tests revealed no rotational bias in the SND group, which persisted for 2 months, but contralateral rotations in the PD group. MicroPET scans revealed glucose hypometabolism and dopamine transporter impairment on the lesioned striatum in the SND group. Tyrosine hydroxylase immunostaining in the SND group revealed that 74.7% of nigral cells on the lesioned side were lost after lesion surgery. These results suggest that the proposed simultaneous double toxin-double lesion method successfully created a rat model of SND that had behavioral outcomes, multitracer microPET evaluation, and histological aspects consistent with SND pathology. This model will be useful for future study of SND.

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BACKGROUND: We investigated whether the intubating condition change acoording to the methods of administration of propofol and rocuronium. METHODS: Ninety adult patients (ASA physical status I or II) undergoing elective surgery were randomly assigned to one of three groups; Group I (n = 30) received rocuronium (0.6 mg/kg) after administration of propofol (2 mg/kg), Group II (n = 30) received propofol and rocuronium simultaneously via different intravenous routes, and Group III (n = 30) received a mixture of propofol and rocuronium via same intravenous route. Intubation was attempted at 60 seconds after administration of rocuronium. Hemodynamic parameters (mean blood pressure, heart rate) were measured before and after propofol administration with 20 seconds interval. Intubating conditions (jaw relaxation, vocal cord movement, and response to tracheal intubation) were evaluated as excellent, good, fair and poor. Train of four counts were recorded at 60 seconds after administration of rocuronium. RESULTS: Excellent intubating conditions were obtained in 13% in group I, 60% in group II, 77% in group III. Mean train of four counts were 3.7 in group I, 3.4 in group II, and 3.5 in group III. Mean blood pressures were decreased gradually after propofol administration in all groups. However, heart rates were not changed in all groups. CONCLUSIONS: At induction of anesthesia, simultaneous or mixed administration of propofol and rocuronium provides excellent or good intubating conditions 60 seconds after rocuronium administration. It could be an effective alternative to succinylcholine for rapid sequence induction of anesthesia.

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BACKGROUND: We investigated whether the intubating condition change acoording to the methods of administration of propofol and rocuronium. METHODS: Ninety adult patients (ASA physical status I or II) undergoing elective surgery were randomly assigned to one of three groups; Group I (n = 30) received rocuronium (0.6 mg/kg) after administration of propofol (2 mg/kg), Group II (n = 30) received propofol and rocuronium simultaneously via different intravenous routes, and Group III (n = 30) received a mixture of propofol and rocuronium via same intravenous route. Intubation was attempted at 60 seconds after administration of rocuronium. Hemodynamic parameters (mean blood pressure, heart rate) were measured before and after propofol administration with 20 seconds interval. Intubating conditions (jaw relaxation, vocal cord movement, and response to tracheal intubation) were evaluated as excellent, good, fair and poor. Train of four counts were recorded at 60 seconds after administration of rocuronium. RESULTS: Excellent intubating conditions were obtained in 13% in group I, 60% in group II, 77% in group III. Mean train of four counts were 3.7 in group I, 3.4 in group II, and 3.5 in group III. Mean blood pressures were decreased gradually after propofol administration in all groups. However, heart rates were not changed in all groups. CONCLUSIONS: At induction of anesthesia, simultaneous or mixed administration of propofol and rocuronium provides excellent or good intubating conditions 60 seconds after rocuronium administration. It could be an effective alternative to succinylcholine for rapid sequence induction of anesthesia.

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