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Xue-Mei Cheng

Publications and source records attributed to Xue-Mei Cheng.

2 recordsLinked to original sources

[Clinical evaluation of high-risk HPV detection by hybrid capture II in screening cervical intraepithelial neoplasma].

OBJECTIVE: To evaluate the value of high-risk HPV (hrHPV) detection by Hybrid Capture II (HC2) in screening cervical intraepithelial neoplasm (CIN). METHODS: Totally 723 patients who had received a dual screening with thinprep cytologic test (TCT) and HC2 in our department were analyzed retrospectively. Among them, 350 patients received a triple examination with TCT, HC2, and colposcopic biopsy. RESULTS: Among the 723 patients, the incidences of hrHPV infection with atypical squamous cell (ASC), low squamous intraepithelial lesion, and high squamous intraepithelial lesion were 70.7% (94/133), 88.9% (249/280), and 90.9% (90/99), respectively, significantly higher than 55.5% (117/211), the incidence of hrHPV infection with normal cytological results (P = 0.005, P < 0.001, P < 0.001, respectively). Among 350 cases who were received triple examination, the incidence of hrHPV infection with cervical intraepithelial neoplasia (CIN) 1 and CIN 2 were 88.9% (72/81) and 96.3% (52/54), significantly higher than 77.7% (153/197), the incidence of hrHPV infection with normal pathological results (P = 0.03, P = 0.002); The incidence of hrHPV infection with CIN 3 and squamous cancer were 91.7% (11/12) and 100.0% (6/6), also higher than normal cases. Among these 350 cases, the incidence of hrHPV infection with ASC was 79.3% (69/87). The incidence of CIN 2-3 with ASC and hrHPV infection was 38.0%, significantly higher than the incidence of CIN 2-3 with ASC and without hrHPV infection (5.9%) (P = 0.04). CONCLUSION: hrHPV infection has a close relation with CIN, and the incidence of hrHPV infection increases along with the severity of CIN.

Adolescent↗

Time-dependent density functional theory study on intramolecular charge transfer and solvent effect of dimethylaminobenzophenone.

The lower singlet excited states for dimethylaminobenzophenone have been investigated as a function of the twisting motion with inclusion of solvent effects. Theoretical calculations have been performed using time-dependent density functional theory. The B3LYP and MPW1PW91 functionals with a 6-311+G(2d,p) basis set have been used to compute transition energies. The solvent effects have been described within the polarizable continuum model. Ground-state geometries are optimized using density functional theory with both B3LYP and MPW1PW91 functionals combined with 6-31G(d) basis sets. Vertical absorption energy calculations characterize the lower singlet excited states both in vacuum and in different kinds of solvents. A large redshift of the absorption maximum in the polar solvent suggests an intramolecular charge transfer character of the excited state. We have constructed the potential energy curves of two possible twisting motions of the excited states both in vacuum and in the polar solvent of acetonitrile: the twisting of only the dimethylamino group and the twisting of the dimethylaminophenyl group with respect to the benzoyl group. Both twisting processes predict the formation of the twisted intramolecular charge transfer state associated with the crossing of a low barrier. The presence of the polar solvent significantly changes the shape of the energy curves. Calculated emission energies for both the isolated and the solvated systems show a large Stokes shift between the absorption and fluorescence maxima. Two possible twisting motions produce similar fluorescence spectroscopic consequences. Our results including solvent effects explain the weak "dual-fluorescence" feature of dimethylaminobenzophenone, and imply that the two possible twisting motions may occur in the excited-state relaxation dynamics, but the twisting of the dimethylamino group seems to take place easier.

Journal Article↗