Objective To establish a method for determination of copper, manganese and cadmium in human urine by transversely heated GFAAS.Methods Matrix modifiers were used and background absorption was deducted, copper, manganese and cadmium in human urine were determined by transversely heated GFAAS after digestion.Results 5 g/L Mg(NO3)2 was taken as the matrix modifier when copper and manganese were determined and 0.3 g/L Mg(NO3)2 and 5 g/L NH4H2PO4 was taken as the matrix modifier when cadmium was determined.Under the designed standard conditions, the detection limits of copper, manganese and cadmium were 0.028-0.060 ?g/L;RSDs were 1.1%-5.1%;Recovery rates were 94.2%-107.5%.Conclusion The method is simple, accurate and sensitive, and is applicable to the determination of copper, manganese and cadmium in human urine.

In hygienic examination experiment teaching,Science inquisition is the important practice for students to gain knowledge and solve problems. In order to enhance students’scientific accomplishment and raise their scientific research ability,inquisition subject design should be highlighted and inquisition horizontal level should be well designed and science inquisition method education should be valued in experiment teaching.

Objective To construct the recombinant pMD19-exon18-exon20 plasmid containing locus G719S and T790M of EGFR gene associated with cervical cancer,which may provide a template for preparing the mutant recombinant vector of EGFR gene.Methods Using the healthy human genome DNA as templates,the segments of exon 18 and exon 20 of EGFR gene were amplified by two pairs of specific primers which were designed based on the sequences of overlapping and complementary area.The amplified segments were linked by overlap PCR.The products of linked exon18-exon20 were further inserted into the vector pMD19-T.The constructed recombi nant pMD19-exon18-exon20 plasmid was finally transformed into competent cells E.coli DH5α and then identified by PCR with bacterial solution and genome sequencing.Results The amplified fragments of exon18 and exon20 were clearly appeared at 778 bp and 596 bp and the fused product of exon18-exon20 was showed at 1 374 bp on agarose gel electrophoresis.The recombinant plasmid of fusion EGFR gene was consistent with the expected results via bacterial PCR assay and DNA sequencing.Conclusion We successfully fused the segments of exon18 with exon20 and constructed the recombinant expression vector of EGFR gene by using overlap PCR method.

OBJECTIVE: To establish a rapid and accurate "on/off" switch technique consisted of 3'-phosphorothioate-modified allele-specific primers and exo+ polymerase to screen the G719S and T790M mutations of epidermal growth factor receptor (EGFR) gene. The switch was used to identify cervical cancer patients who are sensitive to tyrosine kinase inhibitor (TKI). METHODS: Allele-specific primers targeting recombinant wild-type and mutation-type templates were designed with 3' terminal phosphorothioate modification. Two-directional primer extension was carried out using Pfu polymerase. The G719S and T790M mutations were detected by the technique among cervical cancer tissues. The results were verified by Sanger sequencing. RESULTS: No mutation was detected among the 80 cervical cancer cases, and the results were consistent with that of Sanger sequencing. No significant difference was found between the frequencies of the G719S and T790M mutations between the patient and the control groups (P> 0.05). CONCLUSION A sensitive "on/off" switch technique for detecting the two EGFR mutations was established. The G719S and T790M mutations are not associated with cervical cancer.
Carcinoma, Non-Small-Cell Lung ; Drug Resistance, Neoplasm ; ErbB Receptors ; genetics ; Female ; Genes, erbB-1 ; Humans ; Lung Neoplasms ; Mutation ; Protein Kinase Inhibitors ; Uterine Cervical Neoplasms ; genetics