Also. . .

* Los Angeles-based Reliance Steel & Aluminum Co., a metals service center operator, said it has agreed to buy Arrow Metals, a division of Garland, Texas-based Arrow Smelters Inc. Terms were not disclosed.

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* SeraCare Inc., a Los Angeles-based maker of biomedical devices, reported a net loss for its fiscal second quarter ended Aug. 30 of $367,700, or 3 cents a share, contrasted with net income of $706,700, or 6 cents, a year ago. Revenue rose to $13.4 million from $11 million. The company blamed the loss in part on a delay in receiving FDA approval for a $3-million shipment of its products.