NEW YORK (AP) ¿ Shares of Luminex Corp., which makes testing systems for biotechnology companies, fell Friday, a day after it reported lower-than-expected first-quarter results. The stock fell $1.84, or 11 percent, to $15.25 in midday trading. Shares have traded between $12.57 and $27 over the last 52 weeks. Late Thursday, the company said it lost $2.8 million, or 7 cents per share, compared with a loss of $1.2 million, or 3 cents per share, during the same period a year earlier. Revenue rose to $25.6 million from $23 million. Excluding the costs for a legal settlement, the company earned 4 cents per share. Analysts polled by Thomson Reuters expected profit of 5 cents per share on revenue of $29.7 million. The company lowered its full-year revenue outlook to between $125 million and $135 million, from prior guidance of $130 million to $140 million. Analysts expect revenue of about $132.8 million. Wedbush analyst Un Kwon-Casado reaffirmed a "Buy" rating for the company, but cut the price target to $26 from $28, saying the revenue shortfall was partly due to lighter consumable and system sales. "While we are disappointed with the revenue shortfall in the current quarter, driven by seasonality and lumpiness, we remain impressed with the company's ability to control expenses and maintain profitability," Kwon-Casado said in a note to investors.