NEW YORK (CNN/Money) - Some major brokerages weighed in on Gateway, Media General, Occidental Petroleum and Israel-based Teva Pharmaceuticals before the opening bell Thursday.

In a morning note, Credit Suisse First Boston widened its 2003 loss estimate for Gateway (GTW: Research, Estimates) to $1 a share from 50 cents, citing lower gross margin and higher-than-expected costs associated with the computer maker. Shares of Gateway fell 18 cents to $2.92 Wednesday.

Credit Suisse upgraded Occidental Petroleum (OXY: Research, Estimates) to "outperform" from "neutral," citing the petroleum producer's free cash flow and visible growth profile. Shares of Occidental rose 92 cents to $28.69 Wednesday.

The firm also downgraded Media General (MEG: Research, Estimates) to "neutral" from "outperform" and lowered its 2003 earnings estimate for the company, saying it lacks a growth outlook. Shares of the media company fell 47 cents to $56.33 Wednesday.

CSFB increased its 2003 profit estimate for Sierra Health Services (SIE: Research, Estimates) to $1.65 a share from $1.55 after the company raised its forecasts. Shares of the health provider rose 10 cents to $14.72 Wednesday.

Merrill Lynch raised its 2003 earnings estimate for Israel-based Teva Pharmaceutical Industries (TEVA: Research, Estimates) to $1.87 a share from $1.80, citing a strong generic launch of the antibiotic Augmentin and recent approval for a generic version of the antidepressant Remeron. Shares of Teva rose 30 cents to $38.09 Wednesday.

J.P. Morgan upgraded Allied Waste Industries (AW: Research, Estimates) to "neutral" from "underweight," saying its refinancing risk has declined. Shares of Allied Waste fell 58 cents to $9.57 Wednesday.

Lehman Brothers raising its investment rating on AutoZone (AZO: Research, Estimates) to "overweight" from "equal- weight," saying the shares of the automotive parts retailer have already factored in a worst-case scenario. AutoZone shares gained 45 cents to $61.20 Wednesday.  

-- from staff and wire reports