BACKGROUND:Pedicle is the strongest bone structure for the connection between vertebrae and lamina, and the screw fixation through pedicle can provide reliable mechanical basis for the reconstruction of spinal stabilization.
OBJECTIVE:To analyzed the three-dimensional analogue measurement parameters of lumbar pedicle, in order to improve the accuracy and stability of the clinical application of pedicle screw fixation.
METHODS:The original CT data of the spine (L 1-L 5 ) related diseases patients who treated with pedicle screw were analyzed, and the three-dimensional multiplanar reconstruction imaging model was established with Mimics software. By the using of the Mimics software, the lumbar three-dimensional construction was conducted, and the screw length, diameter, transverse section angle and sagittal section angle were predicted, and then statistical y compared with the actual data of the patient postoperative.
RESULTS AND CONCLUSION:Case analysis showed that the position and the length of the screw were good without screw offset and fracture after internal fixation. There were no significant differences in the screw length, diameter, transverse section angle and sagittal section angle between the preoperative predicted parameters and the actual parameter after fixation (P>0.05), while the sagittal section angle of partial segments were smal er than the actual measure value (P<0.05). The lumbar three-dimensional reconstruction and simulation of pedicle screws placement through Mimics software can precisely guide the actual screw placement and improve the safety of pedicle screws placement.

A 21-base, Plasmodium falciparum specific, enzyme-conjugated synthetic DNA probe (PFRl-AP) was used for the diagnosis of falciparum malaria. The blood samples (53 P. falciparum, 5 P. vivax, and 3 P. f and P.v mixed infection cases ) collected from Hainan province were tested. The samples of 32 college students were used for normal control. The probe proved to be specific and sensitive. 10pg of purified P.f DNA could be always detected, and there was no cross reaction with the purified DNA of human leukocytes. When testing Hainan blood specimens, PFRl-AP specifically detected P.f infections. In dot blot, when Nytran membrane with 50 microliters of treated blood samples being used, 39 out of 52 P.f specimens hybridized with this probe positively. When the volume of blotted sample was increased to one hundred microliters, the accumulative total positive rate rose up to 88.46%. The samples of P.v and normal control showed negative reaction with this probe.