FPGA-based digital filter used in ultrasound diagnostic device / 国际生物医学工程杂志

A large real-time processing of ultrasonic signals is a very important part in the ultrasound diagnosis system,especially with digital hardware processing.A key part of the signal processing is the filter design which will affect the performance of ultrasound diagnostic equipment.In this paper,the classification of digital filters is introduced briefly,and a number of hardware implementation methods of digital filter in recent years,especially the realization of FIR filters which belongs to the classical filter based on Distributed Algorithms are discussed.Then a number of advantages and problems of digital filter in recent years are analyzed.On this basis,the paper forecasts its developing trends in the future.

Clinical Analysis on 25 Cases of Malignant Ameloblastoma / 医学研究杂志

Objective To evaluate the clinical feature of malignant ameloblastoma. Methods A review of 25 cases of malignant ameloblastoma was presented with respect to age, sex, primary site and times of recurrence, site and time of metastasis, results of follow up, pathological type. Results Male patients outnumbered female patients by 1.5 to1. The median age at which the primary tumor was first treated was 30.5 years. The primary sites were mandible(17), maxilla(5), tibia(1), rib(1), ulna(1). The most metastases were found in lung(80%), with cervical lymph nodes and liver each representing 24% and 12% of the metastatic sites. Other sites of metastasis included brain(1), femur(1), thoracic spine(1), spleen(1), myocardial(1), mediastinum(1). The median times of primary recurrence was 2.5 times. The median survival time after metastasis was 2 years. There were four pathological types which were follicular type(4), plexiform type(2), acanthomatous type(1), granular type(1). Conclusins Multiple recurrences developed in most of the 25 patients. The time between diagnosis of primary tumor and appearance of metastasis in 25 patients was long. The most frequent sites of metastasis was lung and cervical lymph nodes. Early adequate resection of the primary tumor to avoid repeated surgical intervention is advocated to prevent tumor spread.