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Objective To analyze the results of national personal dose monitoring intercomparison and assessment of Hubei Provincial Hospital for Occupational Disease in 2016—2021, to investigate the influencing factors for monitoring results, and to improve the ability of personal dose monitoring. Methods The assessment was completed according to the requirements of The National Comparison Scheme for Individual Dose Monitoring Ability and Testing Criteria of Personnel Dosimetry Performance for External Exposure (GBZ 207—2016). Results The assessment results were qualified in 2016—2017 and 2020 and excellent in 2018—2019 and 2021. Conclusion The ability of personal dose monitoring in our laboratory has been continuously improved. The monitoring results are accurate and the data processing is standardized, which meet the requirements of relevant standards for personal external exposure dose monitoring.
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<p><b>OBJECTIVE</b>To investigate the role of calcium activated-potassium channels (KCa) in the injury to rat alveolar macrophages induced by quartz.</p><p><b>METHODS</b>The experiments were conducted on a rat alveolar macrophage cell line (NR8383) in vitro, where crystal silica (100 üg/ml) and amorphous silica (100 üg/ml) were used as the test substances and the cells without any treatment as negative controls. At first the effects of two kinds of quartz were compared. Then KCa special inhibitors (Paxilline for BK, Tram-34 for IK, Apamin for SK) were added in different doses to the in vitro test system with 100 üg/ml crystal quartz as matrix, to observe the function of such channels. Cell viability, lactate dehydrogenase (LDH), interleukin-1β (IL-1β) and tumor necrosis factor-a (TNF-α) were tested.</p><p><b>RESULTS</b>Comparing to the negative control group, cell viability reduced, LDH leakage, IL-1β and TNF-α release increased significantly in the amorphous quartz group, furthermore, the effects by crystal quartz were much more serious than those by amorphous quartz, with a statistical significance (P < 0.01). Comparing to the crystal quartz group, IK blockers (Tram-34) led to increase in cell viability significantly, with a statistical significance (P < 0.01); all the KCa specific blockers (Paxilline, Tram-34, Apamin) could reduce LDH leakage and IL-1β release, with a statistical significance (P < 0.05); meanwhile, BK and IK blockers (Paxilline,Tram-34) were able to reduce TNF-α release,with a statistical significance (P < 0.05).Reduction of IL-1β and TNF-α by Tram-34 was dose-dependent, but not so in the other two blockers.</p><p><b>CONCLUSION</b>Blocking calcium-activated potassium channels (KCa) could reduce cell membrane damage as well as IL-1β and TNF-α release induced by crystal quartz in the rat alveolar macrophages cell line in vitro, which might serve as a signal in the early regulation of inflammatory responses by quartz.</p>
Subject(s)
Animals , Rats , Calcium , Metabolism , Cell Line , Interleukin-1beta , Metabolism , Macrophages, Alveolar , Cell Biology , Metabolism , Potassium Channels, Calcium-Activated , Metabolism , Quartz , Toxicity , Tumor Necrosis Factor-alpha , MetabolismABSTRACT
Objective To establish a high-performance liquid chromatography (HPLC) method with diode array detection to simultaneously determine carbamazepine,phenytoin,and phenobarbital in serum.Methods Extraction solvent (800μl ethylene acetate) and sample (0.2 ml) was mixed,extracted for 2 min,and centrifuged (3500 r/min,4 minutes).A volume (600 μl) of extract liquor was volatilized to dryness in water bath with the volatilization temperature 75 ℃,then was redissolved with 1.0 ml mobile phase.Analysis conditions was column temperature 30°,mobile phase (methanol∶ water =40∶60),and detection wavelength of 254 nm.Three metabolites were effectively separated.Results Under the optimized condition,calibration curves of three metabolites were linear in the ranges of (1.52 ～ 120 mg/L) and the correlation coefficients were not less than 0.999.The detection limits (S/N =3) were in the range of 0.4 ～ 1.5 mg/L.The spiked recoveries were in the range of 91.3％ ～ 111％ with relative standard deviations (RSD) less than 5％.Conclusions The optimal pretreatment condition for the sample was established.The chromatographic separation and the detection condition were optimized.The method was sensitive and accurate,and could meet the need of monitoring serum drug concentration.
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There are actually no sufficient data for lifting technique assessment. A laboratory study was undertaken to determine the effect of 3 regular lifting techniques on erector muscle activation, cardiovascular strain and subjective response. Thirty student volunteers participated in the study, and were required to lift a weight with different techniques. Stoop-, squat-, semi-squat-lifting resulted in 3, 2 and 1 time of the highest percentage of the maximum voluntary electrical activation (MVE%) respectively. In the same order, the lowest median frequency (MF) existed 1, 1 and 2 times. Muscle fatigue was 4 times in squat, 36 in semi-squat and 43 in stoop lifting. Heart rate was the highest in squat and lowest in stoop respectively, with a middle level in semi-squat lifting. It may be recommended to adopt mainly the semi-squat technique for daily lifting works. For heavy lifting, it should use the squat technique. Stoop lifting may also be used alternatively but for light things.
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Objective To explore the relationship of depth of trophoblastic invasion with trophoblast cell activity and serum β-hCG according to the expression of proliferation antigen Ki-67 which viewed as an indicator of cell proliferation activity.Methods Fallopian tube specimens collected from 108 patients who underwent operation treatment for fallopian tubal pregnancy in our hospital were investigated by light microscopic examination.They were divided into three groups according to the depth of trophoblastic infiltration: Ⅰ group (stage): trophoblastic invasion of tubal mucosa,Ⅱ group(stage): trophoblastic invasion of the muscularis,Ⅲ group(stage): trophoblast invasion of serosa layer(muscularis penetration).The expression of Ki-67 was detected by SP method and blood β-hCG was detected within 2 hours of preoperative.The level of β-hCG,the expression of Ki-67 and the depth of trophoblast invasion were analyzed.Results Mean level of serumβ-hCG in Group Ⅰ,Ⅱ and Ⅲ were(1416.64 ± 859.94)U/L,(3380.33 ± 2392.36)U/L and(6999.33 ± 4949.90)U/L respectively.Positive expression rate of cell proliferation antigen Ki-67 in Group Ⅰ,Ⅱ and Ⅲ were 21.95％,53.66％ and 6.40％ respectively.There were significant difference on the expression of Ki-67 between group Ⅰ and group Ⅱ,group Ⅱ and Ⅲ group,group Ⅰ and group Ⅲ(x2 =3.94,4.07,4.35,respectively,P ＜ 0.05).The serumβ-hCG level also displayed statistics difference in the three groups(F =9.914,P ＜ 0.01).The positive expression of Ki-67 and serum β-hCG level were positively correlated with each other(r =0.678,P ＜ 0.05)Conclusion The high level of the serum β-hCG indicates high expression of Ki-67 and deeper trophoblast invasion of tubal wall.
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There are actually no sufficient data for lifting technique assessment. A laboratory study was undertaken to determine the effect of 3 regular lifting techniques on erector muscle activation, cardiovascular strain and subjective response. Thirty student volunteers participated in the study, and were required to lift a weight with different techniques. Stoop-, squat-, semi-squat-lifting resulted in 3, 2 and 1 time of the highest percentage of the maximum voluntary electrical activation (MVE%) respectively. In the same order, the lowest median frequency (MF) existed 1, 1 and 2 times. Muscle fatigue was 4 times in squat, 36 in semi-squat and 43 in stoop lifting. Heart rate was the highest in squat and lowest in stoop respectively, with a middle level in semi-squat lifting. It may be recommended to adopt mainly the semi-squat technique for daily lifting works. For heavy lifting, it should use the squat technique. Stoop lifting may also be used alternatively but for light things.
Subject(s)
Adult , Female , Humans , Male , Young Adult , Biomechanical Phenomena , Physiology , Lifting , Muscle Fatigue , Physiology , Muscle, Skeletal , PhysiologyABSTRACT
The roles of voltage-dependent K(+) channels during activation and damage in alveolar macrophages (AMs) exposed to different silica particles were examined. Rat AMs were collected by means of bronchoalveolar lavage, and were adjusted to 5x10(5)/mL. After AMs were exposed to different concentrations (0, 25, 50, 100, 200 mug/mL) of quartz particles and 100 mug/mL amorphous silica particles for 24 h, the voltage-depended K(+) current in AMs was measured by using patch clamp technique. Meanwhile the leakage of lactate dehydrogenase (LDH) and the viability of AMs were detected respectively. Patch clamp studies demonstrated that AMs possessed outward delayed and inward rectifying K(+) current. Exposure to quartz particles increased the outward delayed K(+) current but it had no effect on inward rectifier K(+) current in AMs. Neither of the two K(+) channels in AMs was affected by amorphous silica particles. Cytotoxicity test showed that both silica particles could damage AM membrane and result in significant leakage of LDH (P<0.05). MTT studies, however, showed that only quartz particles reduced viability of AMs (P<0.05). It is concluded that quartz particles can activate the outward delayed K(+) channel in AMs, which may act as an activating signal in AMs to initiate an inflammatory response during damage and necrosis in AMs induced by exposure to quartz particle. K(+) channels do not contribute to the membrane damage of AMs.