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131.
Purpose: Radiotherapy is a very effective tool in the treatment of painful bone metastases. The aim of this study was to compare the palliative effect of radiotherapy between the standard fractionation schedule 20 Gy over 5 fractions (20Gy/5fr) and the high biological dose schedule 27 Gy over 3 fractions (27Gy/3fr) which is frequently used in Stereotactic body radio-surgery (SBRT). Methods: Patients were randomized to receive (20Gy/5fr)or (27Gy/3fr). The primary aim of the study was pain relief using the numeric rating scale (NRS), after three months of radiation therapy. Secondary end points include pain relief immediately after finishing radiation therapy (within one week), and narcotic relief after three months of radiation therapy. Results: Twenty-two patients with painful bone metastases were included. 12 patients received (20Gy/5fr) and 10 patients received (27Gy/3fr). Male patients were predominant on both arms (81.8%) with a mean age of 58 years [ranging between 19-72 years]. For pain relief after three months of radiation therapy, partial pain relief was documented in 9 patients (75%) with (20Gy/5fr) and in 8 patients (80%) with (27Gy/3fr) with a p- value of 0.6. Additionally, narcotic relief after three months was equal for both groups. For immediate pain relief, partial pain relief was seen in one patient (8%) with (20Gy/5fr) versus seven patients (70%) with (27Gy/3fr) with a p value of 0.06. The increase in immediate pain relief in the 27Gy arm was numerically but not statistically significant. Conclusion: SBRT and standard fractionation radiation therapy had equal effectiveness for pain relief, when the assessment was done after three months of radiation therapy. Interestingly, SBRT had a better immediate pain relief.  相似文献   
132.
Recent studies have suggested a potential prognostic role of alterations of the fragile histidine triad (FHIT) gene in diffuse large B-cell lymphoma. To evaluate possible mechanisms of FHIT inactivation and to further clarify its potential prognostic relevance, we analyzed a set of 114 diffuse large B-cell lymphoma with clinical follow-up information. Tissue microarrays were analyzed by immunohistochemistry for protein expression, and corresponding DNA samples were analyzed for FHIT promotor hypermethlyation. Reduced or absent FHIT expression was found in 75 of 114 diffuse large B-cell lymphoma (66%), but was unrelated to clinical tumor stage or patient prognosis. FHIT promotor hypermethylation was observed in 29 of 93 (23%) interpretable diffuse large B-cell lymphoma. Hypermethylation was not significantly correlated to protein expression loss, which could be explained by competing mechanisms for FHIT inactivation in a substantial fraction of non FHIT hypermethylated diffuse large B-cell lymphoma. Hypermethylation was significantly associated with poor prognosis of diffuse large B-cell lymphoma patients and predominantly seen in nongerminal center diffuse large B-cell lymphoma (27%), but less frequent (13%) in germinal center diffuse large B-cell lymphoma. In summary, these data suggest that promotor hypermethylation is responsible for reduced FHIT expression in a substantial subset of diffuse large B-cell lymphoma, which is primarily composed of nongerminal center subtype with poor patient prognosis.  相似文献   
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Abstract

Purpose: Evaluating the long-term impact of faculty development programs (FDPs) can help monitor the effectiveness of the program and identify areas for development. This study examined long-term differences in confidence, knowledge, behaviors, and policies of faculty members who attended FDPs on multiple choice question (MCQ) item analysis and faculty members who did not attend the FDPs.

Methods: A cross-sectional study design was used, by administering a 24-item survey to a representative sample (simple random selection) of 61 faculty members at King Abdulaziz University Faculty of Medicine.

Results: Among respondents, 34% did not attend FDPs; 53% attended 1–3 FDPs; and 13% attended more than 3 FDPs on MCQ item analysis. Results showed that faculty knowledge on elements of MCQ item analysis was significantly greater (p?=?.01) for members who attended the FDPs. Faculty who attended FDPs on MCQ item analysis were twice more likely to conduct item analysis in general (p?=?.020) and four times more likely to conduct item analysis for more than 70% of module examinations (p?=?.005).

Conclusion: FDPs focused on MCQ item analysis can yield systematic changes on faculty confidence, knowledge, and behaviors. Moreover, FDPs also need support from the department and need sustained strategic support to ensure continued effectiveness.  相似文献   
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Objective: The aim of this study was to measure the leakage by two methods with ion chamber and ready packs film, and to investigate the feasibility and the advantages of using two dosimetry methods for assessing leakage radiation around the head of the linear accelerators. Methods: Measurements were performed using a 30 cm^3 ion chamber; the gantry at 0°, the X-ray head at 0°, the field size at between the central axis and a plane surface at a FSD of 100 as a reference, a series of concentric circles having radii of 50, 75, and 100 cm with their common centre at the reference point. The absorbed dose was measured at the reference point, and this would be used as the reference dose. With the diaphragm closed, the measurements were taken along the circumference of the three circles and at 45~ intervals. Results: Leakage radiations while the treatment head was in the vertical position varied between 0.016%-0.04%. With the head lying horizontally, leak- age radiation was the same order magnitude and varied between 0.02%-0.07%. In the second method, the verification was accomplished by closing the collimator jaws and covering the head of the treatment unit with the ready pack films. The films were marked to permit the determination of their positions on the machine after exposed and processed. With the diaphragm closed, and the ready packs films around the linear accelerator the beam turned on for 2500 cGy (2500 MU). The optical den- sity of these films was measured and compared with this of the reference dose. Leakage radiation varied according to the film positions and the magnitude of leakage was between 0.005%-0.075%. Conclusion: The differences between the values of the leakage radiation levels observed at different measurement points do not only reflect differences in the effective shielding thickness of the head wall, but are also related to differences in the distances between the target and the measurement points. The experimental errors involved in dosimetric measurement also contribute to such differences.  相似文献   
136.
Purpose The aim of the present report is to describe abnormal 18F-fluorodeoxyglucose (FDG) accumulation patterns in the pleura and lung parenchyma in a group of lung cancer patients in whom lung infarction was present at the time of positron emission tomography (PET).Methods Between November 2002 and December 2003, a total of 145 patients (102 males, 43 females; age range 38–85 years) were subjected to whole-body FDG PET for initial staging (n=117) or restaging (n=11) of lung cancer or for evaluation of solitary pulmonary nodules (n=17). Of these patients, 24 displayed abnormal FDG accumulation in the lung parenchyma that was not consistent with the primary lesion under investigation (ipsilateral n=12, contralateral n=9 or bilateral n=3). Without correlative imaging, this additional FDG uptake would have been considered indeterminate in differential diagnosis.Results Of the 24 patients who were identified as having such lesions, six harboured secondary tumour nodules diagnosed as metastases, while in three the diagnosis of a synchronous second primary lung tumour was established. Additionally, nine patients were identified as having post-stenotic pneumonia and/or atelectasis (n=6) or granulomatous lung disease (n=3). In the remaining six (4% of all patients), a diagnosis of recent pulmonary embolism that topographically matched the additional FDG accumulation (SUVmax range 1.4–8.6, mean 3.9) was made. Four of these six patients were known to have pulmonary embolism, and hence false positive interpretation was avoided by correlating the PET findings with those of the pre-existing diagnostic work-up. The remaining two patients were harbouring small occult infarctions that mimicked satellite nodules in the lung periphery. Based on histopathological results, the abnormal FDG accumulation in these two patients was attributed to the inflammatory reaction and tissue repair associated with the pathological cascade of pulmonary embolism.Conclusion In patients with pulmonary malignancies, synchronous lung infarction may induce pathological FDG accumulation that can mimic active tumour manifestations. Identifying this potential pitfall may allow avoidance of false positive FDG PET interpretation.  相似文献   
137.
This study was undertaken to identify the clinical value of incidentally detected lesions (IDLs) in the gastrointestinal tract (GIT) with (18)F-FDG PET/CT. METHODS: The reported database of 3,281 patients who underwent partial-body (18)F-FDG PET/CT scans from April 2001 to September 2003 was reviewed. Patients with incidental (18)F-FDG accumulations in the GIT that were associated with concomitant abnormal soft-tissue density or wall thickening on the native CT were evaluated. Incidental PET/CT findings were correlated with endoscopic and histopathologic results. RESULTS: According to our selection criteria, 98 (3%) of the 3,281 patients had an IDL of the GIT on (18)F-FDG PET/CT. Correlative endoscopic findings were available in 69 (70%) of 98 patients. Of these, 13 patients (19%) were harboring newly occurring cancers of the GIT in addition to preexisting aerodigestive tract tumors (n = 12) and malignant melanoma (n = 1). Twenty-nine (42%) patients were identified with precancerous lesions, such as advanced colonic adenomas (n = 27), Barrett's esophagus (n = 1), and intestinal metaplasia of the gastric mucosa (n = 1). Inflammatory and other benign GIT lesions were detected in 12 (17%) and 6 (8%) patients, respectively. In 9 (13%) patients, PET/CT was false-positive, showing normal findings in subsequent endoscopic examinations. In 20 (28%) of 69 patients, PET/CT findings had a relevant impact on the clinical management. Twenty-nine (30%) of the 98 patients were not subject to a further endoscopic examination because of the extent and nature of the primary tumor (n = 17), loss to follow-up (n = 7), death shortly after PET (n = 3), and patient unwillingness (n = 2). CONCLUSION: Although IDLs of the GIT on (18)F-FDG PET/CT scans are found only in about 3% of cases, they are associated with a substantial risk of an underlying cancerous or precancerous lesion. Early identification of these occult lesions may have a major impact on the patients' management and outcome.  相似文献   
138.
Ketamine hydrochloride as sole anesthetic for open liver biopsy   总被引:1,自引:0,他引:1  
We evaluated the use of ketamine as sole anesthetic agent for open liver biopsy, with particular reference to its effect on liver function and hepatotoxicity and its effect on cardiovascular stability and respiration. From 386 patients who underwent liver biopsy at Jordan University Hospital, 12 had open liver biopsy because of contra-indications for closed needle biopsy. The surgical procedure consisted of a small right paramedian incision allowing inspection of the liver surface and a wedge and needle biopsy. Ketamine HCl was used in a dose of 2 mg/kg I.V. with supplemental doses as necessary. No significant fluctuations in cardio-respiratory vital signs were observed. Muscle rigidity and respiratory tagging movements necessitated addition of a muscle relaxant and artificial ventilation in three patients. Six patients reported dreams, two of which were described as nightmares. There was no liver function decompensation, or significant bilirubin or transaminase elevations in the week following the biopsy. Ketamine is a safe anesthetic to use for open liver biopsy in patients with underlying liver disease, although poor muscle relaxation and nightmares may be significant side effects.  相似文献   
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