Objective To compare the value of 64-slice CT and 256-slice spiral CT in the diagnosis of pul-monary embolism.Methods A retrospective analysis CT pulmonary angiography of pulmonary embolism clinical cases,65 cases were in our hospital ,256-slice CT and 64-slice CT angiography were performed within 3 days of onset . The two kinds of inspection equipment for pulmonary embolism detection rate were analyzed and compared , and its image SNR, in contrast to noise ratio ,average scan time and the average dose of contrast agent used for comparison . Results The two devices display rate of pulmonary embolism was 100.0%,in the noise,image SNR,contrast to noise ratio,scan length,the 256-slice CT and 64-slice CT was no significant difference (P>0.05).The average 256-slice CT contrast agent was (4.45 ±1.37) mSv,64-slice CT was (5.68 ±1.06) mSv,there was significant difference between the two (t=2.77,P<0.05),an average of 256-slice CT scan time was (3.68 ±1.29)s,64-slice CT was (7.61 ± 1.40),there was significant difference between the two (t=11.33,P<0.001).Conclusion 256-slice CT and 64-slice CT can be used as an effective means of clinical diagnosis of pulmonary embolism ,but compared with 64-slice CT,the 256-slice CT can significantly reduce the scan time ,reduce the amount of radioactive contrast agent ,which has certain advantages .

Objective To investigate the retroperitoneal ganglioneuroma ( GN) imaging findings ,and analyze its enhanced features .Methods 37 patients with retroperitoneal GN confirmed by pathology were chosen as subjects , the imaging features were analyzed and were compared with the pathologic results .All 37 cases underwent CT scan ,22 patients underwent CT enhance scan .Results 37 cases of retroperitoneal GN ,the lesions were located in the right side in 23 cases,14 cases located on the left.All lesions were demarcated,round or oval in 19 cases,18 cases of irreg-ular shape.CT scan 26 cases of 34 lesions of uniform density ,and density close to cystic lesions ,11 cases of 17 une-ven density,showed a little patchy,small strips calcification.Enhanced arterial phase lesions no enhancement ,venous phase and delayed phase showed progressive enhancement .Conclusion Retroperitoneal GN has certain characteristic imaging findings and strengthen the characteristics contribute to its diagnosis and differential diagnosis .

Objective To discuss the diagnostic performance of MSCT in cystic nephroma(CN).Methods The MSCT findings of CN in 7 patients proved by operation and pathology were retrospectively reviewed.Results All of 7 cases were isolated cystic lesion, including 5 males and 2 females.MSCT scanning showed cystic tumor in the renal parenchyma with well-defined boundary.All cases showed regular cystic wall and septa with no attached cystic wall nodule.The cystic wall and septa appeared homogeneous enhancement on contrast-enhanced CT,while the cystic space showed inhomogeneous density and lack of enhancement.Conclusion The MSCT findings of CN may benefit the definite diagnosis.

Objective To investigate the effect of LAG-3 deficiency (LAG3^-/-) on natural killer (NK) cell function and hepatic fibrosis in mice infected with Echinococcus multilocularis. Methods C57BL/6 mice, each weighing (20 ± 2) g, were divided into the LAG3^-/- and wild type (WT) groups, and each mouse in both groups was inoculated with 3 000 E. multilocularis protoscoleces via the hepatic portal vein. Mouse liver and spleen specimens were collected 12 weeks post-infection, sectioned and stained with sirius red, and the hepatic lesions and fibrosis were observed. Mouse hepatic and splenic lymphocytes were isolated, and flow cytometry was performed to detect the proportions of hepatic and splenic NK cells, the expression of CD44, CD25 and CD69 molecules on NK cell surface, and the secretion of interferon γ (IFN-γ), tumor necrosis factor α (TNF-α), interleukin (IL)-4, IL-10 and IL-17A. Results Sirius red staining showed widening of inflammatory cell bands and hyperplasia of fibrotic connective tissues around mouse hepatic lesions, as well as increased deposition of collagen fibers in the LAG3-/-group relative to the WT group. Flow cytometry revealed lower proportions of mouse hepatic (6.29% ± 1.06% vs. 11.91% ± 1.85%, P < 0.000 1) and splenic NK cells (4.44% ± 1.22% vs. 5.85% ± 1.10%, P > 0.05) in the LAG3^-/- group than in the WT group, and the mean fluorescence intensity of CD44 was higher on the surface of mouse hepatic NK cells in the LAG3^-/- group than in the WT group (t = −3.234, P < 0.01), while no significant differences were found in the mean fluorescence intensity of CD25 or CD69 on the surface of mouse hepaticNK cells between the LAG3^-/- and WT groups (both P values > 0.05). There were significant differences between the LAG3^-/- and WT groups in terms of the percentages of IFN-γ (t = −0.723, P > 0.05), TNF-α (t = −0.659, P > 0.05), IL-4 (t = −0.263, P > 0.05), IL-10 (t = −0.455, P > 0.05) or IL-17A secreted by mouse hepatic NK cells (t = 0.091, P > 0.05), and the percentage of IFN-γ secreted by mouse splenic NK cells was higher in the LAG3^-/- group than in the WT group (58.40% ± 1.64% vs. 50.40% ± 4.13%; t = −4.042, P < 0.01); however, there were no significant differences between the two groups in terms of the proportions of TNF-α (t = −1.902, P > 0.05), IL-4 (t = −1.333, P > 0.05), IL-10 (t = −1.356, P > 0.05) or IL-17A secreted by mouse splenic NK cells (t = 0.529, P > 0.05). Conclusions During the course of E. multilocularis infections, LAG3^-/- promotes high-level secretion of IFN-γ by splenic NK cells, which may participate in the reversal the immune function of NK cells, resulting in aggravation of hepatic fibrosis.