Express train from Kyoto to Nara

Is it possible to catch 'a' Kintetsu line express train from the Sanjo Eki (Kyoto) to the Kintetsu Nara Eki without changing trains? ie: straight through to Nara, and approx. what cost? ... as I will be staying in Sanjo-dori, I'm hoping not to have to go by crowded bus to Kyoto Eki with luggage and catch the JR nara train. Thank you.

No, it is not possible, because Kintetsu does not serve Sanjo Station!

Instead, you could take Keihan Railway from Sanjo to Tambabashi, walk to nearby Kintetsu-Tambabashi Station and catch a train to Kintetsu-Nara.

The other possibility is to take the Tozai Subway Line from Sanjo-Keihan to Karasuma-Oike and then the Karasuma Line and Kintetsu to Kintetsu-Nara. Some trains along the Karasuma Line go all the way to Nara. The others provide transfer opportunity at Takeda Station.

You can look up all the routes and costs here:
http://www.hyperdia.com/

Keihan - Kintetsu Through Sevice at Tanbabashi station has been discontined 45 years before. In other words, There is no direct train at present, but their stations are close to each other.
http://goo.gl/maps/iGaic