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101.
Fas分子与肝细胞凋亡   总被引:7,自引:4,他引:3  
近年来细胞分子生物学领域中的两个重要进展,即细胞凋亡概念的提出和Fas分子的分离与鉴定对肝病的研究有重要影响,加深了人们对肝细胞损伤与死亡的认识.1993年Ogasawaraetal[1]进行的Fas单抗毒性实验证实了Fas分子系统在肝细胞凋亡或损伤...  相似文献   
102.
103.
Although the clinical manifestations such as drowsiness, brisk reflexes, extensor plantar responses and hemisensory disturbance usually are considered to suggest Bickerstaff's brainstem encephalitis (BBE) rather than Miller Fisher syndrome (MFS), the nosological relationship between BBE and MFS has yet to be established. Herein, we report upon a 58-year-old man who showed ophthalmoplegia, ataxia and consciousness disturbance. In the absence of any abnormality on brain MRI, electrophysiological studies and SPM analysis using (18)F-FDG PET showed evidence of brainstem and cerebellum involvements.  相似文献   
104.

Purpose

Preoperative identification of aggressiveness is important for the establishment of a treatment strategy in patients with soft-tissue sarcoma (STS). We compared the predictive values of various metabolic parameters derived from PET/CT with 18F-FDG, including maximal standardized uptake value (SUVmax), total lesion glycolysis (TLG) and metabolic tumour volume (MTV).

Methods

A total of 66 patients with STS who had undergone FDG PET/CT before tumour resection were reviewed retrospectively. We determined SUVmax, TLG and MTV to compare their value in predicting disease progression, which was defined as local recurrence and metastases. Receiver operating characteristic curve (ROC) analysis was used to compare the accuracy. Univariate and multivariate analyses of conventional clinicopathological variables were used to compare the reliability of the metabolic parameters.

Results

TLG exhibited greater accuracy than SUVmax or MTV in ROC analysis (area under curve, AUC, 0.802, 0.726 and 0.681, respectively). The cut-off values for disease progression derived from the AUC data were TLG 250; SUVmax 6.0, and MTV 40 cm3. In univariate analysis, TLG (>250) was a more significant predictive factor than SUVmax and MTV (P?<?0.001, P?=?0.031 and P?=?0.022, respectively). TLG was the only meaningful metabolic parameter in the multivariate analysis (P?=?0.008) other than presence of metastasis at diagnosis (P?=?0.003).

Conclusion

TLG is a more accurate predictor of disease progression than SUVmax or MTV. TLG enables accurate preoperative assessment of aggressiveness comparable with conventional clinicopathological parameters.  相似文献   
105.

Purpose

Lymph node (LN) characterization is crucial in determining the stage and treatment decisions in patient with lung cancer. Although 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) has a higher diagnostic accuracy in LN characterization than anatomical imaging, differentiating between metastatic and inflammatory LNs is still challenging because both could show high 18F-FDG uptake. The purpose of this study was to assess if the heterogeneity of the 18F-FDG uptake could help in differentiating between inflammatory and metastatic LNs in lung cancer, and to compare with other parameters.

Methods

A total of 44 patients with adenocarcinoma of the lung, who underwent preoperative 18F-FDG PET/CT without having any previous treatments and were revealed to have 18F-FDG-avid LNs, were enrolled. There were 52 pathology-proven metastatic lymph nodes in 26 subjects. The pathology-proven metastatic LNs were compared with 42 pathology-proven inflammatory/benign LNs in 18 subjects. The coefficient of variation (CV) was used to assess the heterogeneity of 18F-FDG uptake by dividing the standard deviation of standardized uptake value (SUV) by mean SUV. The volume of interest was manually drawn based on the combined CT images of 18F-FDG PET/CT (no threshold is used). Comparisons were made with the maximum standardized uptake values (SUVmax), visual assessment of 18F-FDG uptake, longest diameter, and maximum Hounsfield units (HUmax).

Results

Metastatic lymph nodes tended to have higher CVs than the inflammatory LNs. The mean CV of metastatic LNs (0.30 ± 0.08; range: 0.08–0.55) was higher than that of inflammatory LNs (0.17 + 0.06; range, 0.07–0.32; P < 0.0001). On receiver operating characteristic (ROC) curve analysis, the area under curve was 0.901, and using 0.20 as cut-off value, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were 88.5 %, 76.2 %, 82.2 %, 84.3, and 83.0 % respectively. Accuracy of CV was slightly higher than SUVmax and diameter, but significantly higher than visual assessment and HUmax.

Conclusions

In patients with adenocarcinoma of the lung having no prior treatments, metastatic LNs showed more heterogeneous 18F-FDG uptake than inflammatory LNs. Measuring the CV of the SUV derived from a manual volume of interest (VOI) can be helpful in determining metastatic LN of adenocarcinoma of the lung. Including diagnostic criteria of CV into the diagnostic approach can increase the accuracy of mediastinal node status.  相似文献   
106.
AIM: The purpose of this study is to present an exact simulation method for mandibular rotational movement in distraction osteogenesis for hemifacial microsomia. METHODS: Three-dimensional (3-D) surgery simulation software programmes (V-Works and V-Surgery; Cybermed, Seoul, Korea) were used, based on 3-D CT data in addition to the conventional data, which included facial photography, panoramic radiograph, cephalogram, and dental models. After measuring the mandibular deficiency (horizontal and vertical) from a 3-D model reconstructed using the software, the angulation of the distraction device to the mandibular border (posterior or inferior) was determined. The rotation axis in the V-Works simulation was defined as the line perpendicular to the plane made by condylion and the distraction vector location on the mandible. The mandible moves along the plane around this rotational axis during distraction. After the 3-D simulation with the software programme, mock surgery on a rapid prototyping model was performed. This planning method was applied to models of two hemifacial microsomia patients. RESULTS: With this protocol, it was possible to simulate the rotational movement of the mandible on the axis passing through the condylar head of the unaffected side. CONCLUSION: The sequential planning procedure presented in this paper is considered to be helpful in performing effective preoperative simulation of distraction osteogenesis for hemifacial microsomia.  相似文献   
107.
A woman with a 5-year history of unilateral orofacial granulomatosis required repeated evaluations (including sequential colonoscopies) to establish the diagnosis of cutaneous Crohn's disease, a condition that proved responsive to low doses of oral methotrexate administered weekly. To our knowledge this is the first report describing the use of methotrexate for treatment of orofacial granulomatosis caused by underlying Crohn's disease.  相似文献   
108.
ObjectiveTo investigate the neurotransmitter enzyme Acetylcholinesterase (AChE) activity in the brain and blood of rats infected with Trypanosoma congolense (T. congo).MethodsPresence and degree of parasitemia was determined daily for each rat by the rapid matching method. AChE activity was determined by preparing a reaction mixture of brain homogenate and whole blood with 5, 5-dithiobisnitrobenzioc acid (DTNB or Ellman's reagent) and Acetylthiocholine (ATC). The increase in absorbance was recorded at 436 nm over 10 min at 2 min intervals. Trypanosome species identification (before inoculation and on day 10 post infection) was done by Polymerase chain reaction using specific primers.ResultsThe AChE activity in the brain and blood decreased significantly as compared with the uninfected control. The AChE activity dropped to 0.32 from 2.20 μmol ACTC min?1mg protein?1 in the brain and 4.57 to 0.76 μmol ACTC min-1mg protein?1 in the blood. The animals treated with Diminaveto at 3.5 mg/kg/d were observed to have recovered significantly from parasitemia and were able to regain AChE activity in the blood but not in the brain as compared to the control groups. We also observed, that progressive parasitemia resulted to alterations in PCV, Hb, RBC, WBC, neurophils, total protein, lymphocytes, monocytes and eosinophil in acute infections of T. congo. Polymerase chain reaction (PCR) of infected blood before inoculation and on day 10 post infection revealed 600 bp on agarose gel electrophoresis.ConclusionsThis finding suggest that decrease in AChE activity increases acetylcholine concentration in the synaptic cleft resulting to neurological failures in impulse transfer in T. congo infection rats.  相似文献   
109.
In a multicentre randomised, unblinded patient preference pilot trial to assess the feasibility of a definitive randomised trial comparing colposuspension with tension-free vaginal tape (TVT) plus anterior repair in women with incontinence and prolapse, we found that 31 of 56 eligible women agreed to participate (55%). Recruitment was more successful face to face (87%) than by letter (16%). Only four of our women agreed to be randomised, 21 (68%) chose anterior repair + TVT and six (19%) chose colposuspension. This study demonstrates the importance of pilot work for complex trials to identify issues likely to adversely affect recruitment.  相似文献   
110.

Purpose

To develop a chemical‐shift–based imaging method for fat quantification that accounts for the complex spectrum of fat, and to compare this method with MR spectroscopy (MRS). Quantitative noninvasive biomarkers of hepatic steatosis are urgently needed for the diagnosis and management of nonalcoholic fatty liver disease (NAFLD).

Materials and Methods

Hepatic steatosis was measured with “fat‐fraction” images in 31 patients using a multiecho chemical‐shift–based water‐fat separation method at 1.5T. Fat‐fraction images were reconstructed using a conventional signal model that considers fat as a single peak at –210 Hz relative to water (“single peak” reconstruction). Fat‐fraction images were also reconstructed from the same source images using two methods that account for the complex spectrum of fat; precalibrated and self‐calibrated “multipeak” reconstruction. Single‐voxel MRS that was coregistered with imaging was performed for comparison.

Results

Imaging and MRS demonstrated excellent correlation with single peak reconstruction (r2 = 0.91), precalibrated multipeak reconstruction (r2 = 0.94), and self‐calibrated multipeak reconstruction (r2 = 0.91). However, precalibrated multipeak reconstruction demonstrated the best agreement with MRS, with a slope statistically equivalent to 1 (0.96 ± 0.04; P = 0.4), compared to self‐calibrated multipeak reconstruction (0.83 ± 0.05, P = 0.001) and single‐peak reconstruction (0.67 ± 0.04, P < 0.001).

Conclusion

Accurate spectral modeling is necessary for accurate quantification of hepatic steatosis with MRI. J. Magn. Reson. Imaging 2009;29:1332–1339. © 2009 Wiley‐Liss, Inc.  相似文献   
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