The Sensex has rebounded into the positive zone and is now up 20 points at 10,843.Earlier in the day, the index opened a tad higher at 10,831 and spurted to a high of 10,898. Selling soon emerged and the index tumbled into the negative zone to a low of 10,623 - down 275 points from the day's high.Hindalco and Cipla have advanced 3.5% each to Rs 198 and Rs 235, respectively.Satyam, Tata Steel and ICICI Bank have gained over 2% each to Rs 703, Rs 521 and Rs 583, respectively.ACC and NTPC have moved up nearly 2% each at Rs 765 and Rs 119, respectively. Dr.Reddy's and SBI have added 1% each to Rs 1,434 and Rs 879, respectively.HDFC has dropped 3.5% to Rs 1,199. ONGC, HDFC Bank and Tata Power have shed over 3% each to Rs 1,197, Rs 760 and Rs 533, respectively.Ranbaxy and Wipro have slipped 2.5% each at Rs 435 and Rs 462, respectively.Reliance and Reliance Energy have declined 2% each to Rs 950 and Rs 539, respectively.Bajaj Auto and Larsen & Toubro are down 1.7% each at Rs 2,930 and Rs 2,295, respectively.Out of 1,973 stocks traded so far, 1,323 have advanced, 623 have declined and the rest are unchanged.