Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

I hope everyone enjoyed our one-day "winning streak" because the broad-based S&P 500 (SNPINDEX:^GSPC) is heading south for the sixth time in seven days as a resolution to a government shutdown appears unlikely before the Tuesday deadline.

The investor concern stems from Congress needing to pass a budget that would fund all of the government's agencies while taking into account the requirement to shave off $85 billion from the budget as mandated by the sequester. As you might imagine, neither Democrats nor Republicans are willing to bend from their perch, making it all the more apparent that certain government agencies will close on Tuesday. I've already examined some of the possible outcomes of a shutdown, and frankly they aren't good!

On the economic front, the final reading from the Michigan Consumer Sentiment survey for September came in slightly higher than economists had expected at 77.5, but still fell to a five-month low. Numerous concerns including the jobs outlook, the looming government shutdown and possible debt-ceiling stalemate, and uncertainties surrounding the implementation of Obamacare, have consumers more worried about their future than at any time over the previous couple months.

All told, the S&P 500 gave back 6.92 points (-0.41%) to finish the week at 1,691.75. The index has now lost about 2% of its value over the past seven trading sessions.

Bucking the trend and leading the charge higher today was health care information technology provider Cerner (NASDAQ:CERN) which advanced 8% after announcing a partnership with Intermountain Healthcare. According to Cerner's press release, the company will deploy its electronic-health record and revenue cycle management software throughout Intermountain's network of 22 hospitals and 185 outpatient clinics. The deal will definitely provide a nice pop to Cerner's bookings moving forward, but at 31 times forward earnings I'm also a bit concerned that investors have already more than accounted for the recent surge in EHR revenue booking growth.

Shares of global footwear and accessories giant Nike (NYSE:NKE) had some pep in its step today, gaining 4.7% after handily beating Wall Street's estimates with its first-quarter earnings results. For the quarter, Nike reported an 8% increase in revenue to $7 billion, noted that constant-currency worldwide future orders rose 10%, and delivered an adjusted profit of $0.86 per share, a 37% increase from the year-ago period. Comparatively, the Street had been expecting only a $0.78 per-share profit from Nike. What makes Nike so successful is its well-known brand ambassadors and easily recognizable brand around the globe. It appears that Nike may finally be putting its Chinese inventory issues in the rear-view mirror, which would make this company quite an attractive buy candidate.

Finally, shares of biopharmaceutical giant Celgene (NASDAQ:CELG) added 3.2% after the company announced the purchase of nearly 667,000 shares of Acceleron Pharma stock. Acceleron just IPO'd last week and has a very small number of outstanding shares, so this move actually gives Celgene control of 27% those shares. Celgene shareholders seem to like the move as Acceleron is an early and midstage developer of protein therapeutics for the treatment of cancer and other rare diseases. All it would take is one successful drug on Acceleron's part for Celgene to reap a nice reward on its investment.

Fool contributor Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.

The Motley Fool owns shares of, and recommends Nike. It also recommends Celgene. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.