Objective To assess the value of CT in the diagnosis of PRF,and analyze the reason of misdiagnosis. Methods Retrospectively analyze the CT data of ten patients with retroperitoneal fibrosis,which were confirmed by the clinical pathology.All the patients underwent CT scan and enhanced scan.Two experienced physicians using the blind method to evaluate the location, boundary, density, invasion on the surrounding tissue and enhancement of retroperitoneal fibrosis lesions respectively.Results All patients with CT scan findings were retroperitoneal irregular-shaped soft tissue lesions,which was similar to muscle density.6 cases with surrounding the retroperitoneal vessel, 2 cases with expansion and hydrops of renal pelvis and ureter.By enhanced scan,9 cases with different degrees of enhancement,1 case without obvious enhancement.6 cases were misdiagnosed as retroperitoneal schwannoma or lymphoma. Conclusion CT can show the characteristics of retroperitoneal fibrosis. Comprehensively analyze various imaging findings is helpful for the diagnosis of retroperitoneal fibrosis. Misdiagnosis reason is mainly due to retroperitoneal fibrosis is a rare disease,and understanding of this disease in imaging findings is insufficient in the daily work.

Objective To investigate the expression of vascular endothelial growth factor (VEGF) and microvessel density (MVD) in colorectal carcinoma, and to study its relationship with the enhancement degree of the lesion on SCT scan. Methods Thirty patients with colorectal carcinoma confirmed by colonofiberscope or operation were examined by SCT, and the CT attenuations were measured. The resected tumor specimens were immunohistochemically stained with CD34 for measuring MVD and stained with VEGF. The results were compared with the enhancement degree of the lesions observed on SCT scan. Results The enhancement correlated well positively with MVD and VEGF of the colorectal carcinoma. The degree of enhancement correlated closely with the blood supply and MVD and VEGF of colorectal carcinoma (r_1=0.5905, P_1=0.0015; r_2=0.4574, P_2=0.0126). Conclusion High expression of VEGF and MVD is a biological label of malignancy(P

Objective To assess the diagnostic value of delayed CT contrast enhancement patterns in hilar cholangiocarcinoma based on two phased dynamic incremental CT scanning. Methods Fifty two patients with suspected hilar tumor and bile duct obstruction underwent spiral CT scan. The scan time for one revolution of the X ray tube was 1 second. To elucidate the delay time for optimal imaging, all proved cholangiocarcinoma with delayed (6、8、10、15、20、30 minutes) post equilibrium phase contrast enhanced CT scans were acquired with unenhanced, dynamic contrast enhanced, and delayed images. Degree of delayed enhancement was compared with that of surrounding liver parenchyma. Results (1) 8～15 minutes after IV injection of contrast material was the delay time for optimal imaging. (2) Of 29 cholangiocarcinomas, the early CT showed hypoattenuating (lower than that of liver parenchyma) in 23 tumors, isoattenuating (equal to that of the liver) in 4 tumors, and hyperattenuating (higher than that of liver) in 2 tumors. The delayed CT scan showed isoattenuating in 8 tumors, hyperattenuating in 21 tumors, and no hypoattenuating. Most of delay imaging of hilar cholangiocarcinoma may appear hyperattenuating ( U=-4.307 3, P

Objective To study the characteristics of organ function and structural injuries in the elderly with multiple organ dysfunction syndrome. Method 50 Wistar rats (25 three-month-old rats and 25 twenty-month-old rats) were anaesthetized and experienced cecal ligation puncture (CLP) operation, which were defined as MODSE group and MODS group respectively. 40 Wistar rats (20 three-month-old rats and 20 twenty-month-old rats) were anaesthetized and not experienced cecal ligation puncture operation, which were used as SOGE (sham operation group in the elderly) and SOG (sham operation group). At 6 h, 12h, 24h, 48h or 72h after operation, serum levels of alanine aminotransferase, aspartate aminotransferase, blood urea nitrogen, creatinine and total bilirubin were measured by automatic biochemistry analyzer. Organs (hearts, brains, lungs, livers, kidneys) were harvested. Paraffin sections were made and stained by conventional H.E procedure for histological examination. Results Based on histological investigations, physiological and biochemical measurements, organ dysfunction in MODSE group occurred at 6h after operation and peaked at 24 h after operations. Otherwise, organ injuries with MODS occurred at 24 h and peaked at 48 h after operation. Conclusion According to histological investigations, physiological and biochemical measurements, damages of organ dysfunction and structural damages in MODSE group occurred much earlier and more seriously. which may provide an experimental evidence for medico-legal certification of the death caused by MODS.

Objective To improve the diagnostic level of uncommon hepatic malignancy in 5 cases with different histopathological nature by analyzing their CT features. Methods CT scan was performed in 5 cases with pathologically proved uncommon malignancy of the liver including hepatic sarcoma ( n =3) and primary carcinoid tumor ( n =2). Results These uncommon malignancies of the liver had a variety of presentations. Undifferentiated embryonal sarcoma presented as a single huge cyst mixing with solid mass. Hepatic angiosarcoma demonstrated as multiple well defined hypoattenuation lesions without cirrhosis. Necrosis, cystic degeneration, and hemorrhage may be accompanied. Malignant fibrous histiocytoma displayed as a single large hypoattenuation lesion within hyperdense septations, and most of the tumor was in the right lobe. Immunohistochemistry had the diagnostic value. The CT features of carcinoid tumor were single or multiple, unilocular or multilocular mixed dense masses. The solid portion of the masses enhanced obviously and carcinoid syndrome may highly suggest the diagnosis. Conclusion The forementioned 5 cases of hepatic malignancy are seldomly seen clinically. Each of them with different pathologic nature has different CT findings, and sometimes with some similar signs. Typical CT findings, coupled with clinical information may lead to a correct diagnosis.

Objective To study the CT characteristics of rare renal malignant tumors.Methods 7 cases with rare renal malignant tumors confirmed by operation and pathology were reviewed and their CT manifestations were analyzed retrospectively.In clinical, all cases had abdomen pain,6 cases had macroscopic haematuria,and 1 case had asymptomatic by chance.Results Of 7 cases,3 ca-ses were sarcomatoid carcinoma,1 case was carcinosarcoma,1 case was malignant mesenchymal tumor,1 case was lymphoma,and 1 case was neuroendocrine carcinoma.The diameter was about 4.0-12.3 cm.1 case had uniform density,6 cases uneven,and the boundary was not clear.Conclusion The rare renal malignant tumors are misdiagnosed easily.Combined clinical data with imaging performance are helpful to make comprehensive analysis,and to improve accuracy rate for diagnosis,definite diagnosis still depends on pathological examination.

Objective To study the imaging features and pathological characteristics of MCRCC in order to improve its diagnostic accuracy. Methods The multi-phase SCT and contrast-enhanced ultrasound were performed in 18 cases of MCRCC proved by the pathology before their operation.The imaging features of MCRCC in 18 patients were reviewed. Results All tumors appeared as well-defined round or oval multilocular cystic masses composed of serous fluid with regular thin cystic wall and an irregular renal shape. There were thin coarse septum(6 cases), thick septum(8 cases) and septum with nodule(4 cases) of all the tumor. Dynamic SCT presented enhancement from slight to moderate degree in thin septum cases, obviously homogeneous enhancement in septum with nodule cases and two different previously enhancement in thick septum cases, so did CEUS. The degree of enhancement correlated well positively with the dynamic SCT and CEUS in 18 cases of MCRCC(P ＜0.05). Conclusion The typical imaging features of MCRCC are multilocular cystic masses composed of serous fluid with regular thin cystic wall, thin coarse septum, thick septum and septum with nodule. There are enhancement from slight to moderate degree in septum cases by SCT and CEUS. The imaging features of SCT and CEUS are integrated in MCRCC, which may improve the accurate diagnosis of MCRCC and provide strong guidance for the clinical treatment.

Objective To develop a superparamagnetic iron oxide (SPIO)-based MR probe containing vascular endothelial growth factor(VEGF) to investigate their biological and chemical properties and targeting effect of colorectal cancer cells in vitro. Methods The anti-VEGF-SPIO probe was fabricated with VEGF antibody and SPIO through chemical method. Its biological and chemical properties and reflexivity were tested with SDS-PAGE and MRL The SW620 cells incubated with anti-VEGF-SPIO probe for 30, 60 and 90 minutes respectively and compared with marrow mesenchymal stem cell at 37℃. The comparison among groups was conducted by using analysis of variance and LSD-t test. The MRI results were confirmed by the Prussian blue staining. The comparison among groups was performed by analysis of variance and factorial experiment. Results SPIO-based MR probe containing VEGF was successfully contributed and isolated. The reflexivity of anti-VEGF-SPIO probe was 0.0426×10~6 mol/s. The immunofluorescence and prussia blue stain proved high expression of VEGF in SW620 cells. Anti-VEGF-SPIO probe and SW620 cellscombined at 37℃ in vitro MRI proved the SW620 cells incubated with anti-VEGF-SPIO probe appeared hypointense on T_2WI and T_2~* WI. MR signal were 392±7,91±8,264±10 for 30, 60 and 90 minutes respectively, which were statistically different from that before incubation 679±12 (F=4735.489, P< 0.01). The intensity decreased most significantly at 60 minutes in vitro. Its MR signal 82±7 were statistically different compared with marrow mesenchymal stem cell 689±43, t=39.167,P<0.05). While SW620 cells incubated without SPIO were not statistically different compared with marrow mesenchymal stem cell, which were 419±59 and 400±41 respectively(t=-0.718,P>0.05). Conclusion Nanoscale iron particles containing the anti-vascular endothelial growth factor molecular probe can evaluate tumor angiogenesis at the receptor level, which provides a new way of the tumor angiogenesis diagnosis and anti-angiogenesis therapy.

The cholesterol esterase and its oxidase were respectively immobilized onto sol-gel(tetraethyl orthosilicate)and then an enzymatic reaction column was prepared. Hydrolysis of cholesterol ester took place in the presence of cholesterol esterase to form cholesterol under catalysis of cholesterol oxidase, and Cholesterol was oxidized to produce hydrogen peroxide which reacted with luminal in the presence of simulated enzyme hemoglobin to result in the emission of light. Thereupon, a chemiluminescence system combined with flow injection technology by sol-gel immobilized enzyme was developed for the determination of cholesterol including free and total amount in human serum. The CL intensity was well linear with the concentration of cholesterol;liner range of total and free cholesterol was 1.01×10~(-6)～2.02×10~(-4) mol/L with a detection limit of 7.5×10~(-7) mol/L) and 5.0×10~(-8)～2.18×10~(-5) mol/L) with a detection limit of 5.0×10~(-9) mol/L respectively. Contrasted the method) with the biochemical analyzer (TBA-120FR), both the methods had no significant difference. This method has been successfully applied for the detection of cholesterol in clinic serum samples.

Objective To investigate the CT features and different risk CT findings of intestinal stromal tumor. Methods The CT imaging data of 25 cases of intestinal stromal tumor confirmed by pathology and compared with operative and pathologic findings were retrospectively studied. Analyzing the CT features based on Histopathologieal classification of the different risk groups and using chi-square test to compare the differences. Results There were 9 cases which tumors originated from the jejunum, and 13 cases from ileum, only 3 cases from duodenum. Among them, 2 cases were submucosal type, 13 cases were intramural type, and 10 cases were subserous type. The pathologic patterns of different risk which included high-risk, intermediated-risk, low-risk, and very low-risk were 12 cases, 7 cases, 5 cases and 1 cases respectively. A typical CT manifestations of intestinal stromal tumors were a outward growth of irregular or round soft tissue mass originated in small intestine which had clear boundary and the non-homogeneous density, which corresponding to necrosis, cystic change, mucoid degeneration and sinus or cavity. Mesenteric fat invaded by tumor showed high-density lines or points shape. The Enhancement of lesion was obvious and not homogeneous which showed little change in peak of enhancement between arterial phase and venous phase. Intestinal stromal tumors took 5 cm as the boundary which including different size, shape, density, and appearance vessel-like artery shadow at arterial phase between different risk groups(low, very low-risk group and intermediated, high-risk group) were statistically different (P ＜0.05), while enhanced degree without significant difference (P ＞ 0.05). Conclusion CT findings of small intestine stromal tumor have characteristics and CT features have significant difference between different risk groups. These features of more than 5 cm in diameter, non-homogeneous density, irregular shape and chaos appearance like vascular enhancement are showed in intermediated-high-risk group.