1.Sequential Injection Instrument for Determination of Urine Iodine
Ying LIU ; Rong ZHANG ; Weijing BU ; Jiebing TANG ; Shan CHEN ; Lixia LIU
Chinese Journal of Analytical Chemistry 2009;37(11):1706-1710
An iodine analysis instrument with sequential injection of urine samples was developed. A method for measurement of urine iodine was also developed by combining sequential injection and catalysis kinetics,and making use of catalysis facilitation of the iodine in the redox reaction of As~(3+) and Ce~(4+) . The sequential injection and stopped-flow stabilization determination were made possible by the program-controlled injector with controlled flow rate and the 16-hole program-controlled selection valves. The arsenic-cerium reaction with iodine-catalyzed at constant temperature state might proceed with the constant temperature flow cell. Using the syringes with program-controlled velocity,pushing and suction,Using the digital connected circuit and micro-iodine determination software,the reaction temperature of (32.0±0.1)℃,injection time of 45 s,stabilization time of 60 s,detection time of 20 s,injection volume of 400μL,linear range of 15 -600μg/L,detecting limitation of 5.01 μg/L(n=11) and recovery rate of 94. 1 % - 105. 1 % were obtained. With this method,the detecting result of the National Standard Reference (GBW09109 and GBW09110) materials was within a given standard range. Through this method,the detecting results had no significant differences comparing with those by standard method of National Health Service(P >0.05).
2.The change of negative pressure in the cupping-cup and its influence on the depth of filiform-needle insertion.
Jing LU ; Xiaoyan CHU ; Lei WANG ; Weijing TANG ; Yubao ZHOU ; Pinglong SUN
Journal of Biomedical Engineering 2010;27(1):71-74
This study was designed to observe the negative pressure in the cup during cupping, and to investigate the influence of negative pressure on the depth of filiform-needle inserted and retained. In the beginning, the change of pressure after cupping on acupoint BL23 for a span of 20 minutes was recorded. Acupuncture on acupoint BL23 was performed; the filiform-needle was retained and followed by cupping at different levels of negative pressure, and the changes of the depth of needle insertion was measured. The results showed: the absolute value of the negative pressure in the cup goes down with time and is significantly lower after 20 minutes (P < 0.05); the negative pressure in the cup causes the retreat of the inserted needle; and under the same pressure, there is a greater length measurement in needle retreat for male than for female (P < 0.01). The length of needle retreat is related to the pressure in the cupping-cup and to gender.
Acupuncture Points
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Acupuncture Therapy
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methods
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Combined Modality Therapy
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Female
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Humans
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Male
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Medicine, Chinese Traditional
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methods
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Pressure
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Sex Factors
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Young Adult