Objective To discuss the value of ultrasonic miniature probe (UMP) in the preoperative staging of colorectal cancer.Methods Sixty-one colorectal cancer patients were examined before operation using the UMP (Olympus UM-2R,12 MHz).According to the intestinal wall structural layers and the close organic infiltration,the tumor encroaching depth was judged and the diagnosis of the T stage was made.All cases got the pathological verification,which was compared with the stage of UMP.Results The general diagnostic accurate rate of tubal wall encroaching depth (T stage) by the UMP was 86.9% (53/61) in the colorectal cancer and the diagnostic accurate rate was 100.0% (3/3) in the early stage cancer.UMP stage and TNM stage showed a better consistency (Kappa=0.790).Conclusions UMP has high accurate rate in the judgment of the colorectal cancer encroaching depth.There is some value in the T stage diagnosis before operation,which could help patients with colorectal cancer select suitable therapies.

Objective: To investigate the effect of bone marrow mesenchymal stem cells (MSC) on the variation of intestinal permeability damaged by superior mesenteric artery ischemia and reperfusion. Methods: Bone marrow mesenchymal stem cells were isolated from cavity of tibias and femurs of male Sprague Dawley rat in a sterile condition, and were cultured and proliferated in plastic dishes. 10 week old female Sprague Dawley rats were randomly divided into three groups:group A (sham group), group B (MSC group) and group C (saline group). In group B and group C, the superior mesenteric artery (SMA) of the animals were seperated and occluded by non-invasive vascular clamp for 45 minutes. Immediately after removing the vascular clamp,1×10~7 MSC suspended in 0.5 ml sterile L-DMEM and the same volume of normal saline was submucosally injected into the small intestine at ten different points in group B and group C, respectively. In group A, the animals were only underwent laparotomy without clamping the SMA. 3 days and 6 days after the operation, 100 mg lactulose and 50mg mannitol dissolved in 2 ml distilled water were administrated by oral gavage and urine during 6 h experiment was collected for assaying the L/M ratio before sacrificing the animals. The donor derived MSC was identified by Y chromosome in situ hybridization in ileum tissue, and the serum D-lactate level was determined. Results: The donor derived MSC could home to the ischemia/reperfusion injured intestinal mucosa, and the intestinal permeability was much lower in group B (MSC group) than that in group C (saline group)(P<0.05). Conclusion: Mesenchymal stem cells can reduce the small intestinal mucosal permeability impaired by ischemia/reperfusion, and can participate in the preservation of integrity of the damaged gut mucosal mechanical barrier.