Objective: To investigate the possible presence ofan active efflux system in resistance tofluoroquinolones in Mycoplasma hominis. Methods: The resistant strains of M. hominis wereselected from one hundred and three cl...Objective: To investigate the possible presence ofan active efflux system in resistance tofluoroquinolones in Mycoplasma hominis. Methods: The resistant strains of M. hominis wereselected from one hundred and three clinical strainsof M. hominis by broth microdilution method. The ac-cumulation of ciprofloxacin in M. hominis and the in-fluence of carbonyl cyanide m-chlorophenyl-hydrazone(CCCP) and reserpine were measured by a fluores-cence method. Results: Two resistant strains and two susceptiblestrains of M. hominis were selected in vitro. The accu-mulation of ciprofloxacin for resistant strains is lowerthan that of susceptible strains. CCCP and reserpinehad different influence on clinical strains of M.hominis. Reserpine could dramatically increase theaccumulation of ciprofloxacin, however CCCP had alittle effect on it. Conclusion: These results suggest that the pres-ence of an active efflux system implicated in thefluoroquinolones-resistant in M. hominis.展开更多
In this paper, the authors design boundary feedback controllers at the interior node to stabilize a star-shaped network of Euler-Bernoulli beams. The beams are pinned each other, that is, the displacements of the stru...In this paper, the authors design boundary feedback controllers at the interior node to stabilize a star-shaped network of Euler-Bernoulli beams. The beams are pinned each other, that is, the displacements of the structure are continuous but the rotations of the beams are not continuous. The weil-posed-ness of the closed loop system is proved by the semigroup theory. The authors show that the system is asymptotically stable if the authors impose a bending moment control on each edge. Finally, the authors derive the exponential stability of the system.展开更多
基金Financially supported by a grant from the Education Committee of Hunan Province(No.00A009)
文摘Objective: To investigate the possible presence ofan active efflux system in resistance tofluoroquinolones in Mycoplasma hominis. Methods: The resistant strains of M. hominis wereselected from one hundred and three clinical strainsof M. hominis by broth microdilution method. The ac-cumulation of ciprofloxacin in M. hominis and the in-fluence of carbonyl cyanide m-chlorophenyl-hydrazone(CCCP) and reserpine were measured by a fluores-cence method. Results: Two resistant strains and two susceptiblestrains of M. hominis were selected in vitro. The accu-mulation of ciprofloxacin for resistant strains is lowerthan that of susceptible strains. CCCP and reserpinehad different influence on clinical strains of M.hominis. Reserpine could dramatically increase theaccumulation of ciprofloxacin, however CCCP had alittle effect on it. Conclusion: These results suggest that the pres-ence of an active efflux system implicated in thefluoroquinolones-resistant in M. hominis.
基金supported by the National Natural Science Foundation of China under Grant No.61174080
文摘In this paper, the authors design boundary feedback controllers at the interior node to stabilize a star-shaped network of Euler-Bernoulli beams. The beams are pinned each other, that is, the displacements of the structure are continuous but the rotations of the beams are not continuous. The weil-posed-ness of the closed loop system is proved by the semigroup theory. The authors show that the system is asymptotically stable if the authors impose a bending moment control on each edge. Finally, the authors derive the exponential stability of the system.
