The All Ordinaries Index (ASX: XAO) is up 1.4% over the Australia Day holiday-shortened trading week, with three ASX All Ords stocks doing more than their share of the heavy lifting.

One provides data solutions and services for machine learning and artificial intelligence (AI).

The second is an Australian gaming technology company.

And the third outperforming ASX All Ords stock on my list is a clinical-stage biotechnology company.

Which high-flying stocks am I talking about?

Read on!

Three ASX All Ords stocks roaring higher

The first ASX All Ords stock to deliver shareholders outsized gains this week is Mesoblast Ltd (ASX: MSB).

Shares in the company, which specialises in allogeneic cellular medicines to treat inflammatory diseases, closed last Friday trading for $2.87. At the time of writing today, shares are changing hands for $3.12 apiece, up 10.6%.

That brings the Mesoblast share price gains over the past year to… wait for it… 1,055%!

Mesoblast share enjoyed an added push higher today following the release of the company's fourth-quarter results and trading update.

Investors have been bidding up the share price as Mesoblast continues to make significant progress with a range of its promising drug candidates. That included receiving US Food and Drug Administration (FDA) approval in the December quarter for its Ryoncil (remestemcel-L) product for the treatment of steroid-refractory acute graft versus host disease.

Moving on to our second high-performing ASX All Ords stock of the week, we have Aristocrat Leisure Ltd (ASX: ALL).

Shares in the gaming technology company closed last Friday at $68.95. At the time of writing, those same shares are trading for $75.04, up 10.6%.

This sees the Aristocrat Leisure share price up 69% in a year. Aristocrat shares also trade on a partly franked trailing dividend yield of 1.1%.

There has been no price-sensitive news from Aristocrat since the company released its full-year results in November. But the stock may have gotten an added boost this week after Goldman Sachs upgraded it to a buy rating with a price target of $78.00 a share.

Which brings us to our third outperforming ASX All Ords stock for the week, Appen Ltd (ASX: APX).

Shares in the language data-focused tech company closed last Friday trading for $2.45. At the time of writing today, they are swapping hands for $2.75 each, up 10.9%.

With the past week's gains factored in, the Appen share price is up a blistering 733% in a year.

Much of those gains were delivered today, following yesterday's release of Appen's December quarter update.

The company reported fourth-quarter revenue of $66.7 million, up 23.3% from the prior quarter. The revenue boost was spurred by growth in Appen's generative AI projects.