RESUMO
We demonstrate that chromatic dispersion induced pulse-width broadening can be effectively monitored by a simple average power measurement of the filtered output from a parametric amplifier when additional four-wave mixing interactions are introduced. This all-optical technique also provides all-optical frequency conversion of the signal being monitored and signal gain.
RESUMO
Uterine zonal anatomy as visualized on T2-weighted (repetition time, 2,500 msec; echo time, 80 msec) magnetic resonance (MR) images consists of a high-intensity central (endometrial) zone, a subjacent low-intensity junctional zone of myometrium, a moderately intense zone of myometrium, and a thin, low-intensity subserosal zone of myometrium. To better define the histologic correlates of these diagnostically significant zones, T2-weighted MR images of 17 in vivo and 13 extirpated human uteri were compared with histologic sections of 17 uteri stained with hematoxylin-eosin, Mallory trichrome, and immunofluorescence staining for actin. Morphometric and electron microscopic observations of uterine surgical specimens were also made. The observations indicate that both the junctional zone and the subserosal zone consist of compact smooth muscle fibers with little extracellular matrix compared with the myometrium proper. Also, the junctional zone is divided into a compact region and a transitional region. The compact region correlates well with the hypointense MR appearance of the junctional zone.