(ShareCast News) - FTSE indices were mixed heading towards the closing bell on Thursday, with the blue-chip index helped south by oil stocks undermined by crude's weakness and Royal Dutch Shell's second-quarter shocker."An unsurprisingly indecisive session in Europe has seen the likes of the FTSE largely flat-lining as traders reduced their risk overnight ahead of the week's risk event from the Bank of Japan," said Joshua Mahony, market analyst at IG."Commodities have enjoyed a particularly volatile second half of this week, with crude continuing to tumble heavily on a global supply glut alongside evidence that fund managers are heavily shorting crude prices," he said.In the Oil & Gas Producers sector, Shell's second-quarter profits adjusted for one-offs and inventory changes, dived 72% to $1.05bn due to lower oil prices and narrower refining margins.Sibling sector Oil Equipment, Services and Distribution was down as the market react to a rise in US inventories on Wednesday, and fears the black liquid faces a demand cliff amid a chronic global glut.Within the Healthcare grouping, Smith & Nephew revealed its interim profits were hit by forex headwinds. Pre-tax profits fell to $453m, from $481m.Looking to the upside, Aerospace & Defence was on the front foot behind Rolls-Royce as it said first-half pre-tax losses came in at £2.15bn from a £310m profit last year.This was largely a result of a revaluation of the company's US-dollar hedge book after sterling's recent collapse in the wake of the UK's vote to quit the European Union.In the same sector, BAE Systems booked a first-half net profit of £418m, from £398m a year ago as revenues rose to £8.7bn, from £8.4bn.The company said the UK's decision to leave the EU would lead to a period of uncertainty but did not anticipate any material near-term trading impact on business.Fixed-Line Telecommunications received a boost as BT Group confirmed an encouraging start to its financial year. In the June quarter, adjusted pre-tax profit was £802m, up 16%.Astrazeneca guided the Pharmaceuticals & Biotechnology mob north as it posted first-half results on Thursday, despite operating profit sliding 24% to $1.341bn, with core operating profit dropping 14% to $2.999bn.Among the metals diggers filling out the Mining sector, Anglo American narrowed its first-half pre-tax loss to $364m, from $1.92bn, and said it was on track to achieve its net-debt target of less than $10bn at end-2016.It and other miners benefited as safe-haven gold rose after the US Federal Reserve held its key interest rate last night, and as traders looks to Bank of Japan's policy meeting on Friday.Against the backdrop, BHP Billiton said the Samarco dam disaster in Brazil would hit full year profits by an extra $1.1bn-$1.3bn.Top performing sectors so far todayAerospace and Defence 4,721.13 +4.31%Fixed Line Telecommunications 4,727.91 +3.07%Pharmaceuticals & Biotechnology 14,676.79 +1.89%Software & Computer Services 1,969.49 +1.68%Mining 11,723.69 +0.87%Bottom performing sectors so far todayElectricity 9,141.01 -4.31%Health Care Equipment & Services 7,664.86 -3.00%Oil Equipment, Services & Distribution 13,416.41 -2.74%Automobiles & Parts 6,747.66 -2.47%Oil & Gas Producers 7,321.46 -2.40%