Objective To obtain magnetic resonance imaging(MRI) symptoms that could be used in medical diagnosis and identification by analyzing the diverse MRI appearance of brain multiple sclerosis(MS).Methods MRI findings of 41 samples of clinically definite MS, including the numbers, distributions, sizes, and shapes of the lesions were analyzed. The symbolic characteristics and enhanced expression are also covered.Results Brain MS might happen singly and multiply, and more frequently with multiple happening. In a multiple case, 4—15 lesions were observed the most. Some samples showed with diffuse lesions which were unable to be counted accurately presenting as a “dirty-appearing white matter”. The distribution of the lesions was observed most frequently at the two sides of periventricle, and following by the subcortical, corpus callosum, and brainstem. Only two lesions were observed at cerebrum. The size of most lesions range from a few millimeters to 2 cm, accounting for about 75% of the total samples. Lesions with size above 2 cm were seen seldomly, with the biggest one of 6—7 cm. According to the shapes and symptoms, lesions might be categorized as an acute and chronic ones. The acute lesions had a shape of oval or circle, with a swelling appearance, low signal of T_1WI, and isointensity or a slightly higher signal on the circle. T_2WI showed a high signal, with different increase and showing “core+lunar” sign. This kind of lesions showed an enhancement with the circle enhancement as the most typical one, which had a complete circle or non-conplete arc shape enhancement, even the big lesions. The chronic lesion might also be divided into two categories. One was the quasi-symmetric lesion, with the distribution along two sides of periventricle and with the shape of small puncture/patch, part of them merged into the big patch; another kind of lesions was found scattered sparsely at frontal, parietal lobes and two sides of the periventricle, with small patches in shape. The chronic lesions had an appearance of shrinking, sharp edge, even signals, and had no lunar circle phenomena and obvious enhancement.Conclusion Brain MS have diverse MRI appearence, with some of which are unique and symbolic.

Objective To evaluate the accuracy of MR diffusion weighted imaging (DWI) in the diagnosis of hyperacute cerebral infarction. Methods Twenty one patients with onset of strokelike symptoms underwent conventional MRI and DWI within 6 hours. Results DWI indicated cerebral infarction in 16 patients, all of whom had a final diagnosis of acute stroke. DWI was negative in 5 patients, all of whom had a final diagnosis of TIA. The abnormality seen at DWI was confirmed with follow up study. DWI had a sensitivity of 100% and a specificity of 100% in the diagnosis of hyperacute cerebral infarction, and conventional MRI interpretation yielded a sensitivity and specificity of 25% and 100%, respectively. Conclusion DWI is highly accurate in diagnosing hyperacute cerebral infarction and is superior to conventional MRI.

Objective To explore the MRI and pathologic characteristics of hippocampal sclerosis. Methods 16 patients with hippocampal sclerosis were examined with transvers and oblique coronal T 1 weighted,T 2 weighted and fluid attenuated inversion recovery(FLAIR) MR imaging. Results Of 16 patients,1 case had bilateral hippocampal sclerosis;15 cases were ipsilateral(left n =9,right n =6) proved by pathology.The MR features of hippocampal sclerosis were as follows:hippocampal atrophy present in all patients;hyperintensity on coronal FLAIR in all patients and on coronal T 2W images present on 15 sides; loss of superficial sulci hippcampal head seen in 11 sides;disruption of the internal structures present on 13 sides; atrophy of lateral white matter present on 7 sides; enlargement of the ipsilateral temporal horn present on 6 sides;atrophy of the ipsilateral temporal lobe seen on 2 sides. Conclusion Atrophy and hyperintensity on coronal FLAIR and T 2 weighted images were the most common features of hippocampal sclerosis and had positive diagnostic value. Combination of coronal FLAIR and T 2 weighted imaging could improve the diagnostic sensitivity and accuracy for hippocampal sclerosis.

Objective To assess the clinical history and MRI findings of pituitary adenoma of different hormonesecreting type.Methods We retrospectively studied 200 postoperated patients,from 1996 to 2000,who all had the preoperated MRI exams.All cases had histopathological evalutions.Both clinical presentation(age,sex,symtom,sign)and MRI findings(size,form,signal intensity,extension)were investigated.Results There was a great span of age with sixty percent owing for 35～55 years old.The male and female proportion was 1∶2 in PRL hormone-secreting pituitary adenoma.12 cases with luleinizing hormone-secreting and 2 cases with thyrotropin hormone-secreting pituitary adenoma were just male.In other types the incidences were similar in man and woman.Clinical symptom and sign present overlapping.The volume of tumor was from 0.5 cm?0.8 cm?1 cm to 6 cm?7 cm?8 cm with most multihormone adenoma's maxium dimension out of 5 cm.The signal intensity was not characteristic pre-and post-enhancement.No calcification could be seen.In term of extension,most was to suprasellar,then infrasellar,unilateral or bilateral sinus cavernous,last was to lower part of the third ventricle.Conclusion Different hormonesecreting pituitary adenomas have some speciality in clinical and MRI presentation.Although an accurate diagnosis can not be made according to it,more information have been obtained.

Objective To quantitatively evaluate the influence of fluid attenuated inversion prepared recovery (FLAIR) on apparent diffusion coefficient (ADC) and its clinical application value. Methods The data of DWI and FLAIR-DWI of 139 stroke were retrospectively reviewed. Paired t-test was used to analyze DWI (ADCCON ) and FLAIR-DWI (ADCFLAIR) values at varying time points from hyperacute to chronic stage. All of the lesions were further divided into cortex involved infarction and subcortical infarction. The ADCCON and ADCFLAIR values in the lesion sides and the contralateral sides were compared separately. Results The mean ADCCON values for lesions less than 6 hours, 7--12 hours, 13--24 hours, within 2 days, 3-4 days, 5-7 days and 8--14 days were not significantly different from those of the ADCFLAIR values(P >0.05) [ADCCON were (0.55±0.07), (0.50±0.09), (0.50±0. 13), (0.50 ± 0. 13), (0.62 ± 0. 14), ( 0. 60 ± 0. 12), (0. 72 ± 0. 20) × 10-3 mm2/s; ADCFLAIR were ( 0. 53 ± 0. 09 ), (0.49±0.06),(0.49±0.10),(0.48±0.08),(0.58±0. 14), (0.60±0.09),(0.73±0.15) × 10-3 mm2/s]. Lesions of 15 to 30 days [ (0. 95±0. 21 ) × 10-3 mm2/s and ( 1.02±0. 27) × 10-3 mm2/s for ADCFLAIR and ADCCON ] and the chronic stage ( >31 days) [ ADCFLAIR and ADCCON were (1.10 ± 0. 30) × 10-3 mm2/s and (1.36±0. 41 ) × 10-3 mm2/s respectively], had a significantly lower ADCFLAIR than those of the ADCCON (P <0. 01 ). For patients with a symptom duration of less than 14 days, the mean ADCFLAIR values of the cortex involved and subcortical lesions were all not significantly different from the mean ADCCON (P > 0. 05 ) [ ADCCON were ( 0. 55 ± 0. 16 ), ( 0. 61 ± 0. 14 ) × 10-3 mm2/s ; ADCFLAIR were (0.53±0. 14), (0.60±0. 13) × 10-3 mm2/s]. For patients with a symptom duration of longer than 14 days, the mean ADCFLAIR values of the cortex involved and subeortical lesions were all significantly lower than those of the mean ADCCON values [ ( 1.16±0. 36) × 10-3 mm2/s vs. ( 1.35±0. 48) × 10-3 mm2/s for cortex involved lesions and (0. 97±0. 19) × 10-3 mm2/s vs. ( 1.15±0. 33) × 10-3 mm2/s for subcortical lesions ] (P < 0. 01 ). The ADC values of the normal contralateral sides were significantly decreased after the fluid inversion prepared pulse was conducted [ ADCFLAIR, ( 0. 76 ± 0. 05 ) × 10-3 mm2/s and ADCCON, (0. 82 ± 0. 11 ) × 10-3 mm2/s ] ( p < 0. 01 ). Conclusions The FLAIR significantly decrease the absolute ADC values of the ischemic lesions 14 days later after the stroke onset, which may be helpful in determining individual lesion age. Meanwhile, the application of FLAIR can have a more accurate relative ADC value by reducing the free fluid partial volume effect of the normal contralateral side, and hence enhance the ability of detecting the subtle ischemic pathophysiological changes.

Objective: To study the effect of intracellular-free calcium and the expression of Fas and Fas L on the process of pancreatic carcinoma cell apoptosis. Methods: Apoptosis induced by 2 μmol/L arsenic trioxide in pancreatic cancer cell lines SW-1990 was investigated.Concentration of intracellular-free calcium （［Ca2+］i） was determined by Fura-2a fluorescein load technique. Fas and FasL were determined by flow cytometry. Results: Pancreatic cancer cells treated with 2 μmol/L arsenic trioxide presented apoptotic features: intact cell membrane, chromatin condensation, nucleic fragmentation and apoptotic body formation; agarose electrophoresis showed marked ladder; flow cytometery analysis showed a sub-G1 cell peak. In the process of pancreatic carcinoma cell apoptosis Fas and FasL and the ［Ca2+］i were significantly higher than that in the control. Conclusion: The pancreatic cancer cell apoptosis induced by arsenic trioxide is related to Fas and FasL expression by the cancer cells and the ［Ca2+］i increase in the cancer cells.

Objective: To select the telomerase positive cancer cell lines of gastrointestinal tract and to provide a convinced methodology for future telomerase study. Methods: Fifteen cancer cell lines (carcinoma of stomach 4, of liver 6, of pancreas 2, of colon 3) were cultured and telomerase activity were detected by TRAP-ELISA. The normal hepatic cells were taken as control. Results: Thirteen cell lines were telomerase positive in the 15 lines(86.7%). Conclusion: Most of gastrointestinal tract cancer lines express telomerase, indicating the detection of telomerase activity has clinical potential.

Objective: To study the effect of intracellular free calcium and the expression of Fas and Fas L on the process of pancreatic carcinoma cell apoptosis. Methods: Apoptosis induced by 2 ?mol/L arsenic trioxide in pancreatic cancer cell lines SW 1990 was investigated.Concentration of intracellular free calcium ([Ca 2+ ]i) was determined by Fura 2a fluorescein load technique. Fas and FasL were determined by flow cytometry. Results: Pancreatic cancer cells treated with 2 ?mol/L arsenic trioxide presented apoptotic features: intact cell membrane, chromatin condensation, nucleic fragmentation and apoptotic body formation; agarose electrophoresis showed marked ladder; flow cytometery analysis showed a sub G 1 cell peak. In the process of pancreatic carcinoma cell apoptosis Fas and FasL and the [Ca 2+ ]i were significantly higher than that in the control. Conclusion: The pancreatic cancer cell apoptosis induced by arsenic trioxide is related to Fas and FasL expression by the cancer cells and the [Ca 2+ ]i increase in the cancer cells.

Objective To study the different patterns of hippocampal atrophy by MRI segmental analysis and to investigate the etiology and pathogenesis of temporal lobe epilepsy Methods GE 1 5 T Signa Horizon LX MRI scanner was used Oblique coronal T 1 weighted images perpendicular to the long axis of the hippocampus were obtained The mesial temporal structures were divided into four parts: the amygdala, hippocampal head, body and tail MRI patterns of atrophy in 50 patients with histologically confirmed hippocampal sclerosis were investigated by MRI volumetric measurement and segmental analysis, and the differences of clinical features and surgical outcome in different groups were compared Results Diffuse hippocampal atrophy was found in 22 of 50 patients (44%), 5 of the 50 patients (10%) showed diffuse atrophy involving both the amygdala and hippocampus 20 of the 50 patients (40%) had hippocampal focal atrophy and 8 of 50 patients (16%) had no obvious atrophy 38 of 50 (76%) hippocampal sclerosis had atrophy in the hippocampal body, 29 of 50 (58%) had hippocampal head atrophy, 24 of 50 (48%) had hippocampal tail atrophy, and the least involved part was the amygdala (16%, 8/50) 10 patients who had normal hippocampal volume showed focal hippocampal atrophy by segmental analysis Various patterns of hippocampal atrophy were found to be statistically related to the duration of epilepsy, the frequency of seizure and the outcome of surgery, respectively ( P 0 05) Conclusion MRI segmental analysis can improve the diagnostic sensitivity of temporal lobe epilepsy and help to investigate its etiology and pathogenesis

0.05). Four lesions were only revealed on CE FLAIR whereas 7 lesions were only found on postcontrast T_1WI. Enhancing lesions located in cerebral hemisphere or the forth ventricle was revealed much more on T_1WI than that on CE FLAIR. However, postcontrast fast FLAIR images may be useful in detecting superficial abnormalities and those located in sulcus or lateral ventricle. The enhancement degree of enhanced T_1WI was much more intense than that of CE FLAIR(P0.05) and statistical significance in GWC, CNR and CER(P