HOUSTON -- Scientists gather routinely at the Texas Medical Center to share research. But they are meeting this weekend in enemy territory for a war-room session on political strategy. Advocates of embryonic stem cell research from the fields of academia, politics, health care and medicine -- including South Korean cloning pioneer Hwang Woo-suk -- are plotting ways to quell opposition and get the research money flowing. -------------------- Houston's medical center is an oasis of support for the proponents gathering this weekend. ------------------ Siegel said legislation like some of the measures considered in Texas "sends a message to the biotech community:...