The

Dow Jones Industrial Average

continued to trade above 10,000, but was well off its session highs, as the market's major barometers turned mixed at midmorning.

Amid the Dow 10,000 hoopla, market breadth was negative on both the

New York Stock Exchange

and the

Nasdaq Stock Market

.

The Dow so far has been powered by

United Technologies

(UTX) - Get Report

, which was up 2 11/16 to 134 11/16.

The blue-chip average was up 20 to 10,018. At its peak, the Dow was up 87.69 to 10,085.31 before fading.

The Dow's surge as of late has been astounding. Since March 3, the Dow has risen approximately 742 points.

"The next couple of years look terrific too" for the Dow, said a bullish Steven Adler, president of

Vector Index Advisors

.

For the Dow, its price-to-earnings ratio is less than the

S&P 500

, noting that Dow components give a better price, better dividends and better earnings than the broad market, said Adler.

As for Dow 10,000, Adler said: "This landmark isn't anything special because we're in the first third of a golden era" started eight to 10 years ago, an era he said has "a lot left in it."

Meanwhile, the S&P 500 was down 1 to 1316.

The

Nasdaq Composite Index

was down 9 to 2454. The small-cap

Russell 2000

down 1 to 398.

TheStreet.com Internet Sector

index was up 1 to 619.

TheStreet.com E-Commerce Index

was down 1 to 116.

Today's triple witching -- the expiration of index options, equity options and index futures options -- is also a factor which is expected to influence prices today.

The 30-year Treasury bond was up 2/32 to 96 19/32, yielding 5.49%.

On the NYSE, decliners were beating advancers 1,427 to 1,189 on 342 million shares. On the Nasdaq, losers were beating winners 1,707 to 1,402 on 334 million shares.

On the NYSE, 41 issues had set new 52-week highs while 41 had touched new lows. On the Nasdaq, 50 issues had set new lows while new highs totaled 47.

On the Big Board,

America Online

(AOL)

was most active, with 12 million shares changing hands. It was up 1 3/4 to 117 15/16.

On the Nasdaq,

Cambridge Technology Partners

(CATP)

was most active, with 15 million shares changing hands. It was down 9 1/16, or 43%, to 11 15/16. Yesterday the company warned it expects to post first-quarter earnings of 12 cents to 14 cents a share due to slower sales. The

First Call

23-analyst forecast called for 24 cents vs. the year-ago 20 cents.

9:51 a.m.: Dow Breaks Through 10,000 Convincingly at Open

The

Dow Jones Industrial Average

opened above 10,000 and was firmly higher early on as it renews its quest to close above 10,000.

The Dow was up 52 to 10,050. The

S&P 500

was up 4 to 1321. The Dow and S&P 500 both closed at record highs yesterday.

The

Nasdaq Composite Index

was up 16 to 2479. The

Russell 2000

was down fractionally at 399.

TheStreet.com Internet Sector

index was up 15 to 633. The index is again in record territory after closing at a record high yesterday.

TheStreet.com E-Commerce Index

was up 3 to 119.

The 30-year Treasury bond was up 4/32 to 96 20/32, yielding 5.48%.

Most Up at Open -- NYSE

STMicroelectronics (STM) - Get Report, up 5 1/8 to 102 1/2

.

Most Up at Open -- Nasdaq

RealNetworks (RNWK) - Get Report, up 9 to 136

.

Most Down at Open -- NYSE

Providian (PVN) , down 1 11/16 to 111 7/8

.

Most Down at Open -- Nasdaq

Cambridge Technology Partners (CATP) , down 9 11/16 to 11 5/16

: The company yesterday warned it expects to post first-quarter earnings of 12 cents to 14 cents a share due to slower sales. The

First Call

23-analyst forecast called for 24 cents vs. the year-ago 20 cents.