SHANGHAI, July 17 (Reuters) - China stocks closed up on Friday, overcoming a mid-week slide to end up for a second week, with market insiders saying the "national team" of brokerages, mutual funds and market regulators were intensifying intervention, especially in the futures market.
The main indexes slid sharply on Tuesday and Wednesday, spurring worry that bearish sentiment in the futures market could widen.
The CSI300 index of the largest listed companies in Shanghai and Shenzhen rose 3.9 percent, to 4,151.50, up 1.1 for the week, while the Shanghai Composite Index gained 3.5 percent, to 3,957.35 points, up 2.1 for the week.
China CSI300 stock index futures for July rose 3.7 percent, to 4,124.4, or 27.10 points below the current value of the underlying index. All other traded index futures also rose, in particular futures tracking the small-cap CSI500 index. <0#CIC:>.
But so far none of the contracts which extend to December are pricing at levels equivalent to the unofficial government target of 4,500 points on the SSEC, at which point intervention would theoretically cease.
Total volume of A shares traded in Shanghai was 47.9 billion shares, while Shenzhen volume was 30.6 billion shares. (Reporting by Pete Sweeney; Editing by Richard Borsuk)