Randomization was performed in blocks of four without any stratification. The utmost interval allowed between the qualifying ultrasonographic randomization and study was 48 hours. The day of randomization was defined as day 1. No routine ultrasonographic examinations were required through the follow-up period. The study was conducted according to the ethical concepts mentioned in the Declaration of Helsinki and local regulations. The protocol was accepted by an independent ethics committee, and created informed consent was obtained from all patients before they underwent randomization.In these assays, cells crawl across the surface of a matrix, touring in one plane. But a fresh study indicates that approach misses some essential phenomena. Working in the labs of Whitehead Member Paul MIT and Matsudaira professor Douglas Lauffenburger, postdoctoral researcher Muhammad Zaman found that cells move quite differently in three dimensions. His study, which focused on individual prostate tumor cells, appeared this week in the web early edition of Proceedings of the National Academy of Sciences. Related StoriesJumping genes: a marker for early cancer analysis? An interview with Dr KazazianNew research reveals pivotal part of miR-506 biomarker in gastric cancerNew diagnostic technology predicated on computer algorithms can quickly identify source of cancer Two-dimensional assays ignore the obstacles that cells encounter in their natural contexts, explains Zaman, who recently became an associate professor at the University of Texas at Austin.