Objective To study the method for determination of micro and trace chloroform and carbon tetrachloride in wa-ter by headspace chromatography.Methods Based on the mild solubility of chloroform and carbon tetrachloride in water,trace chloroform and carbon tetrachloride in water were analysed by static headspace gas chromatography using an OV-101chromato-graphic column.Results The better linear ranges for chloroform and carbon tetrachloride were0.00-20.0?g /L(r=0.9998)and0.00-1.00?g /L(r=0.996)respectively.The detection limits of chloroform and carbon tetrachloride were0.19?g /L and0.01?g /L respectively.The recovery rate of the method was95%-110%.Conclusion The method could be satisfactorily used for determination of chloroform and carbon tetrachloride in mineral water,well water,pure water and source-water with the advantage of less interfering factors and no secondary pollution.

Objective:To explore the effects of superparamagnetic iron oxide-short hairpin RNA ( SPIO-ShRNA) dual functional molecular probes of different concentrations on morphology and biological beha -vior of ovarian cancer SKOV3 cells in vitro.Methods:The dual functional molecular probes at an iron concentration of 5, 15, 30, 45, 75, and 100 mg/L were transfected into SKOV3 cells.The transfection rate of the probe was observed by fluorescence microscope .The distribution and content of iron particles in SKOV3 cells were determined by Prussian blue staining , atomic adsorption spectrometer and electron microscopy .Cell viability was observed by cell counting kit-8 ( CCK-8 ) .The apoptosis was detected by flow cytometry .The expression of protein within the cells was detected by Western blot .The changes of the signal intensity were measured by magnetic resonance imaging (MRI).Results: The SPIO-ShRNA dual functional molecular probe was uptaken in aconcentration-dependence manner within a certain range (5-30 mg/L) .When the concentration of the probe was 45 mg/L, the labeling rate of the cell was close to 100%;With the increase of the concentration of probe , the cell survival rate decreased gradual-ly.The cell survival rate of each experimental group were 94.626%±1.050%, 93.373%±1.180%, 91.700%±3.122%, 75.100%±4.362%, 72.983%±3.233%, 71.010%±2.910%,5, 15, 30mg/L cell survival rate was not significantly decreased , the difference was not statistically significant (P=0.226, P=0.068, P=0.475);When the concentration of the probe was greater than or equal to 45 mg/L,the survival rate decreased obviously ( P<0.001);Group of 45 mg/L protein expression rate was 68.905%± 3.510%, When the concentration of the probe was greater than or equal to 45 mg/L, the inhibition rate of the protein expression level of epidermal growth factor receptor was obviously higher than those of 5, 15, and 30 mg/L groups, the difference was statistically significant (P<0.001, P=0.001, P=0.003, all P<0.01);the MRI displayed that the signal intensity was decreased with increasing concentrations of the probe.The signal intensity of 45 mg/L group was 165.55 ±4.92, compared with the blank control group (same volume of phosphate buffer saline ), normal group(unlabeled ovarian cancer SKOV3 cells), 5, 15, and 30 mg/L groups , the signal intensity of 45 mg/L group decreased significantly (all P<0.001).Con-clusion:The dual functional molecular probe can effectively transfect and specifically inhibit the expression of SKOV3 cell lines at the iron concentration of 45 mg/L, and can also be detected by MRI .The role of diagnosis and treatment of the dual functional molecular probe has been initially confirmed .

OBJECTIVE： To observe the efficacy and safety of fluorouracil combined with paracetamol in the treatment of knee osteoarthritis and its effects on related indexes. METHODS： Totally 115 patients with knee osteoarthritis admitted to our hospital from March 2015 to March 2018 were divided into control group （57 cases） and observation group （58 cases） according to medication plan. Control group was given Paracetamol tablets 0.3 g orally， 3 times a day， for consecutive 8 weeks. Observation group was additionally given intra-articular injection of Fluorouracil injection 0.075 g on the basis of control group， once a week， 4 times as a treatment course， for 2 courses in total. Clinical efficacies， VAS scores， Lysholm knee scores， Fugl-Meyer Assessment （FMA） scores， Barthel indexes， WHO QOL-BREF scores before and after treatment and the occurrence of ADR of 2 groups were observed. RESULTS： The total response rate of observation group was 94.83％， which was significantly higher than 78.95％ of control group （P＜0.05）. Before treatment， there was no statistical significance in VAS score， Lysholm knee scores， FMA scores， Barthel index or QOL-BREF scores between 2 groups （P＞0.05）. After treatment， VAS scores of 2 groups were significantly lower than before treatment， and the observation group was lower than the control group； Lysholm knee scores， FMA scores， Barthel indexes and QOL-BREF scores were significantly higher than the same group before treatment， and observation group was significantly higher than control group （P＜0.05）. There was no statistical significance in the incidence of ADR between 2 groups （P＞0.05）. No severe ADR was found in 2 groups during treatment. CONCLUSIONS： Fluorouracil combined with paracetamol can significantly improve therapeutic efficacy of patients with knee osteoarthritis， and can significantly improve knee function， motor function， self-care ability and quality of life without increasing the occurrence of ADR.