1.Medical monitor purchase decision based on quantitative performance evaluation
Lulu ZHANG ; Qiao TIAO ; Xiaowei SUN
Chinese Medical Equipment Journal 2017;38(2):135-137,141
Objective To realize scientific allocation of medical monitors in clinical departments by evaluating quantitatively their social and economic benefits.Methods Analyses were executed on social and economic benefit indexes,including number or times of patients involved,utility time,volatility of utilization rate (VOUR),payback period and investment yield.Results Totally 457 monitors were involved in the study from January to June 2015,and the monitors had the number or times of patients being 20,utility time being 383 h,VOUR lower than 10% (except that of February),mean payback period being 0.64 a and yearly mean investment yield being 137%.Conclusion The monitor has to be allocated by the equipment division in case of low social benefit.In case of high social benefit while low economic benefit,the monitor manufactured in China gains advantages due to short payback period,high investment yield and long free warranty time.The foreign monitor with specific function has to be selected in case of high social and economic benefits as well as requirements on special function.
2.Changes of Na(+) channels in rat hippocampal CA1 neurons in early development after birth.
Jia-Qi QIAO ; Ai-Li LIU ; Tiao-Tiao LIU ; Xin TIAN
Acta Physiologica Sinica 2013;65(2):201-209
The purpose of this research is to investigate the critical period of voltage-gated Na(+) channel development in hippocampal CA1 neurons. Changes of Na(+) currents in acutely isolated hippocampal CA1 neurons of rats at different ages (0-4 weeks after birth) were recorded using the whole-cell patch-clamp technique. The results indicated that the maximum current density of Na(+) channels was increasing with age, and the amplitudes in 1, 2, 3 and 4 weeks respectively grew by (42.76 ± 4.91)%, (146.80 ± 7.63)%, (208.79 ± 5.28)% and (253.72 ± 5.74)% (n = 10, P < 0.05) compared with that in 0 week. The current density in CA1 neurons of 1-2 weeks after birth increased more significantly than those of other groups. The activation curve of Na(+) channel shifted to the left. The half-activation voltages (mV) in 0-2 weeks were -39.06 ± 0.65, -43.41 ± 0.52, -48.29 ± 0.45 (n = 10, P < 0.05), respectively, showing significant age-dependent decrease, and there were no significant changes in other groups. The slope factors of activation curve for each group did not change significantly. There were no regular changes in inactivation curve and no significant changes in half-inactivation voltage. The slope factors of inactivation curve in 1-2 weeks were: 5.77 ± 0.56, 4.42 ± 0.43 (n = 10, P < 0.05). The inactivation rate of the second week after birth was faster than that of the first week, and there were no significant changes during 0-1 week and 2-4 weeks. The recovery from inactivation curve of Na(+) channel shifted to the left. The recovery time declined in 1-3 weeks. Changes of action potential properties were consistent with Na(+) current. These results suggest that the period of 1-2 weeks after birth may be the critical development period of voltage-gated Na(+) channel in hippocampal CA1 neurons. During this time, the distribution of Na(+) channel increases significantly; the activation curve of Na(+) channel shifts to the left; inactivation rate increases as well as recovery time shortens.
Action Potentials
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Animals
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CA1 Region, Hippocampal
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cytology
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Neurons
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physiology
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Patch-Clamp Techniques
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Rats
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Sodium Channels
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physiology