Mad Money Uncovered: PerkinElmer

Trade-Ideas LLC identified PerkinElmer (PKI) as a "barbarian at the gate" (strong stocks crossing above resistance with today's range greater than 200%) candidate

Timing is everything, and investing short term may keep you from opportunities, Cramer says.

Here are Tuesday's top research calls, including downgrades for Capital One, Cisco Systems, Fifth Third Bank and PulteGroup.

Trade-Ideas LLC identified PerkinElmer (PKI) as a "barbarian at the gate" (strong stocks crossing above resistance with today's range greater than 200%) candidate