Biological Activities and Potential Oral Applications of N-Acetylcysteine: Progress and Prospects.

N-Acetylcysteine (NAC), a cysteine prodrug and glutathione (GSH) precursor, has been used for several decades in clinical therapeutic practices as a mucolytic agent and for the treatment of disorders associated with GSH deficiency. Other therapeutic activities of NAC include inhibition of inflammation/NF-B signaling and expression of proinflammatory cytokines. N-Acetylcysteine is also a nonantibiotic compound possessing antimicrobial property and exerts anticarcinogenic and antimutagenic effects against certain types of cancer.

[An experimental study on the adaptation of three kinds of porcelain fused-to-metal restorations].

Objective: To compare the adaptation of porcelain fused-to-metal (PFM) restorations made from Ni-Cr alloy, precious alloy and galvanized forming copings after cementation and to provide a theory guidance for their application.

Methods: Three kinds of crowns (Ni-Cr alloy, precious alloy and galvanized forming) were manufactured and cleaned by ultrasonic vibrate with alcoholic solution for 5 minutes, and cemented on their dies as their order. All the crowns were cemented by polycarboxylate zinc-cement and maintained 10 minutes.

[Effects of varying the opaque thickness and the type of metal ceramic alloy on color].

Objective: To compare the color differences of different metal bases and different opaque thickness, and evaluate the best thickness of opaque on different metal bases.

Methods: Precious metal, gold sediment and Ni-Cr plates were prepared as bases, then opaque samples of 0.05, 0.