New Delhi, Jan. 10 -- The Indian stock market remained sideways on Thursday as the Nifty 50 index once again remained in the tight 23,500 to 23,700 range. On the Nifty weekly expiry session, the Nifty 50 index finished 139 points lower at the 23,549 mark; the BSE Sensex ended 528 points lower at 77,620, whereas the Bank Nifty Index finished 286 points lower at 49,548. However, the selling pressure extended beyond large-caps, with mid-cap and small-cap indices continuing their downward trajectory. The Nifty Mid-cap 100 Index declined 0.93%, while the Nifty Small-cap 100 Index saw a steeper fall of 1.35%. Market breadth remained decisively negative, with the BSE's advance-decline ratio at 0.45, indicating significantly more declining shares...