Folic acid-O-carboxymethyl chitosan ultrasmall superparamagnetic iron oxide nanoparticles (FA-OCMCS-USPIO-NPs) are a novel molecular targeting MR contrast agent. This paper reperts the pharmacokinetics and magnetic resonance response characteristics of FA-OCMCS-USPIO-NPs in normal rats and mice, and discussed its distributing regularity in animals, providing basis for tumor targeting imaging. O-phenanthroline method was used to determine iron content in rats' plasma and mice's organs following high and low doses of nanoparticles injected through tail vein, and the blood concentration-time curve was drawn, the calculated t1/2 of two groups were greater than 7 h. The results of tissue distribution showed that only a small part of nanoparticles were swallowed by the liver and spleen, while none in the heart, lung and kidney. At the same times, the phagocytosis of nanoparticles did not change with the dose. The results of MRI showed that renal excretion occurred 4 hours after injection, and signal to noise ratio (SNR) of liver and kidney returned to normal levels 24 hours after injection. There were no nanoparticles in the lungs. So a part of nanoparticles escaped from phagocytosis of liver and spleen, and it owned lower toxicity and longer half-life. indicated its use for tumor-targeting imaging. All of these indicated its use for tumor-targeting imaging.

Objective To evaluate the efficacy of discriminant function analysis for pericolic infiltration in colorectal cancer on enhanced 64-slice spiral CT and to improve the diagnostic accuracy and specificity of pericolic infiltration. Methods Dynamic enhanced 64-slice spiral CT was performed in 49 colorectal cancer patients (49 masses in total) before surgery. One or two slices were selected for each mass, with a total of 96 slices. The 96 slices were classified into two groups (pericolic infiltration or nonpericolic infiltration group) according to pathological data. Discriminant analysis was performed on the CT values between the mass and the corresponding pericolic tissue 5 mm from the mass at different time points as follows; 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, and 75 s. The discriminant function was calculated, and the pericolic infiltration determined by discriminant function and CT morphology were compared with the pathological results. The CT values in pericolic and non-pericolic infiltration groups at different enhancement time points were assessed using analysis of variance. Results The mean CT values ranged from (43. 6 ±7. 8) HU to (52. 3 ±0. 8) HU in the pericolic infiltration group, and ranged from (100.4±20.3)HU to(116.2±21.4)HU in the non.perieolic infiltration group.At 20 s and 40 s,the mean CT vshle8 were(43.6±27.8)HU and(50.9±27.8)HU in the perleolic infiltration group, (102.0±16.9)HU and(116.2 ±21.4)HU in the non-perieolic infiltration group,respectively.The mean CT value in the pericolic infiltration group was significantly lower than that in the non-pericolic infiltration group at all contrast enhancement time points(F=6.278,P<0.01).A diseriminant function Was obtained as follows:D=-3.450+0.023Xl±0.017X2-0.00lX12-0.001X22+0.002X1×X2. Based on the CT morphology of colorectal cancer,69 slices were identified correctly and 27 slices were fulsely interpreted.the sensitivity.speeificity and accuracy for perieolic infiltration determination were 82.5%,64.3%and 71.9%.respectively.Based on diseriminant function,85 slices were identified correctly and 11 slices were falsely interpreted.the sensitivity,specificity and accuracy were 85.0%.91.1%and 88.5%,respectively.Conclusion The discriminant function with dynamic enhanced 64-slice spiral CT can improve the diagnostic accuracy and specificity of perieolic infiltration in eolorectal cancer patients.

Objective To analyze the imaging features and to enhance the understanding of pancreatic and renal involvement in yon Hippel-Lindau disease (VHLD). Methods CT and MRI appearances and clinical data of six patients with pancreatic and renal involvement in VHLD were studied retrospectively.Six patients underwent CT scanning, and two of them also had MRI.Results Pancreatic cysts found in all six patients varied from several small cysts to cystic replacement of the entire gland.Calcifications were detected in four patients. Multiple bilateral renal lesions were detected in six patients.The renal lesions were classified as cystic, cystic with solid components and solid.Multiple combined renal lesions were found in five patients, and multiple simple cysts in one patient.Unilateral nephrectomy was performed in two patients, and the renal masses were diagnosed as clear cell carcinoma by pathology.Bile carcinoid was found in one patient, and retroperitoneal metastasis in another.Conclusion Multiple pancreatic cysts and/or multiple and bilateral combined renal lesions are highly suggestive of VHLD.

Objective To analyze the effect of evidence based practice on feeding after spinal operation. Methods To formulate an answerable question, find the best available evidence, appraise the evidence and formulate the recommendations by using the method of evidence-based medicine. A total of 60 postoperative patients who received spinal operation were divided into observation group and control group (30 cases in each group). Those patients in control group received the routine diet guidance and the guidelines for the standardization of intake and consumption after spinal cord surgery were used for patients in observation group. The outcomes were evaluated by postoperative recovery and complications of patients after spinal operation. Results There were no significant difference in the incidence of nausea, vomiting , bloating and celialgia in the 5 hours after surgery and 2 hours after feeding between the two groups (P>0.05). The incidence of thirst and hunger in the 5 hours after surgery in observation group were 3.33％(1/30) and 13.33％(4/30).The incidence of thirst and hunger in the 5 hours after surgery in control group were 80.00％(24/30) and 83.33％(25/30). There were statistically significant in the incidence of thirst and hunger in the 5 hours after surgery between the two groups (χ2=36.27, 24.09, P<0.05). There were not statistically significant in the time of anal exsufflation and first defecation time between the two groups(P>0.05). Conclusions Evidence-based practice in the use of guidelines for the standardization of intake and consumption after spinal cord surgery can guide clinical practice.