The changes of some parameters of Gray type Ⅰ synaptic interface in the brain of mice treated with desglycinamide-arginine-8-vasopressin (DGAVP) have been analysed quantitatively two hours after DGAVP injection. The animals were killed and the hippocampus and sensori-motor area of cerebral cortex were prepared for electron microscopy. The electron microphotographs were analysed by IBM-PC computer image processing system. The main results of the experiment are as follows:1. The thickness of postsynaptic density apparently increased in both the sensori-motor area of cerebral cortex and CA_3 area of hippocampus after injection of DGAVP (P

Objective To evaluate the diagnosis and differentiation of solitary pulmonary nodule (SPN) using dynamic spiral CT scan of thin collimation.Methods The thin collimation no-enhanced CT scan and contrast enhanced scan in 30 seconds,1 minute,1 minutes,2 minutes,5 minutes,10 minutes,and 15 minutes after administration of media 100 ml were performed in 38 cases. Results The mean enhanced CT numbers of lung cancer and inflammatory pseudotumor were much higher than that of tuberculosis(TB) and hamartoma and statistically significant in different time of enhancement;20 HU was the threshold for a positive test,the sensitivity was 100% and the specificity was 96%.In time-attenuation curve analysis,lung cancer reached peak enhancement about 2 minutes,inflammatory pseudotumor in 5 minutes and keep longer enhanced time than that of lung cancer.No marked enhancement in SPN of TB and harmatoma,but ring-shaped enhancement can be seen in some of TB.More valuable imaging signs were found with thin collimation scan and more accurate to measure the CT numbers than traditional scan.Conclusion Dynamic spiral CT scan of thin collimation is a very valuable method for diagnosis and differentiation of SPN.

Objective To research the procedure for creating an animal model of mitral regurgitation by implanting a device through the apical artificial chordae tendineae, and to assess the stability and dependability of the device. Methods Twelve large white swines were employed in the experiments. Through a tiny hole in the apex of the heart, the artificial chordae tendineae of the mitral valve was inserted under the guidance of transcardiac ultrasonography. Before, immediately after, and one and three months after surgery, cardiac ultrasonography signs were noted. Results All models were successfully established. During the operation and the follow-up, no swines died. Immediately after surgery, the mitral valve experienced moderate regurgitation. Compared with preoperation, there was a variable increase in the amount of regurgitation and the values of heart diameters at a 3-month follow-up (P<0.05). Conclusion In off-pump, the technique of pulling the mitral valve leaflets with chordae tendineae implanted transapically under ultrasound guidance can stably and consistently create an animal model of mitral regurgitation.