[Nitrogen removal in earthworm ecofilter treating domestic wastewater].

The removal efficiency of different forms of nitrogen was studied in earthworm ecofilter treating domestic wastewater, and the mechanisms were discussed. Results indicated that, the major form of total nitrogen (TN) in influent water and effluent water were existed as ammonia-nitrogen (NH4+ -N) and nitrate-nitrogen (NO3- -N), respectively. NH4+ -N /TN in influent water and NO3- -N /TN in effluent water were 83.

Expression of endothelin receptor subtypes in the spiral ganglion neurons of the guinea pig.

Objective: Endothelin 1 has many biological activities including regulating the functions of auditory system. The present study aimed to investigate the expression of the endothelin receptors in spiral ganglion neurons and its significance in the auditory transmission.

Methods: The cochleae of healthy guinea pigs were fixed, decalcified, embedded in paraffin and serially sectioned.