Environmental exposure to lead and cadmium and hearing loss in Chinese adults: A case-control study.

Hearing loss is the second most common nonfatal problem affecting the Chinese population. Historical studies have suggested an association between exposure to heavy metals, such as cadmium and lead, and hearing loss. Few studies have investigated this relationship in the general population in China.

Temperature effects on enzyme activity of chicken liver esterase used in calorimetric biosensor.

The temperature effects on enzyme activity at the conditions with and without inhibition, operation, and storage were investigated for free esterase and immobilized chicken liver esterase with three methods (adsorption, adsorption-microcapsule, and adsorption-crosslinking) used in a calorimetric biosensor. The results indicated that the temperature had significant effects on the enzyme activity by means of catalytic reaction, irreversible denaturation, mass transfer, and structure deformation of resin. Among all the esterase, the adsorption-crosslinking immobilized esterase had the best performances of enzyme activity retention ratio (EARR), above 96% in operation and 90% in storage on condition of maintaining its response to dichlorvos.

[The best concentration ratio of propofol controlled-infusion combined with sevoflurane in anesthesia for patients undergoing laparoscopy].

Objective: To investigate the best concentration ratio of propofol controlled-infusion combined with sevoflurane in anesthesia for patients undergoing laparoscopy.

Methods: One hundred patients undergoing cholecystectomy under laparoscopy were randomly divided into 5 equal groups treated with propofol controlled plasma at the concentrations of 1, 2, 3, 4, and 5 microg/ml respectively (Group 1-5). Bispectral index (BIS) was maintained at a range of 50 +/- 5 by adjusting sevoflurane inhalation.

[Nipple-areolar reconstruction with the modified arrow flap].

Objective: To introduce the clinical experience of nipple-areolar reconstruction with the modified arrow flap.

Methods: The arrow flaps were modified for nipple-areolar reconstruction in 12 cases. Among them, 2 cases were treated with combined thin split-thickness skin graft; 4 cases with autologous rib implant and tattoo; 6 cases with tattoo.

A thermal biosensor based on enzyme reaction.

Application of the thermal biosensor as analytical tool is promising due to advantages as universal, simplicity and quick response. A novel thermal biosensor based on enzyme reaction has been developed. This biosensor is a flow injection analysis system and consists of two channels with enzyme reaction column and reference column.

[Breast reconstruction with a combined skin flap of DIEP and TRAM].

Objective: To evaluate breast reconstruction with a combined skin flap of the deep inferior epigastric perforator (DIEP) and the transverse rectus abdominis musculocutaneous (TRAM).

Methods: The DIEP and TRAM united flap was elevated with the vessel pedicle of the deep inferior epigastric perforator on the affected side and the rectus abdominis muscle pedicle on the intact side. The reconstructive breast was shaped after the deep inferior epigastric vessels were anastomosed to the internal mammary vessels or the thoracodorsal vessels ipsilaterally.