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101.
Background. Resection of pulmonary metastases (PM) by pneumonectomy is infrequently performed and benefits are uncertain.

Methods. From 1985 to 1995, 42 patients underwent pneumonectomy for PM. Twenty-nine patients had PM from sarcomas, 12 patients from carcinomas, and 1 patient from melanoma. The indications for pneumonectomy were pulmonary recurrences in 12 patients, PM centrally located in 26 patients, and high number of PM in 4 patients. There were 11 intrapericardial and 6 extended pneumonectomies. The average number of PM resected was 3. Twenty-two patients (52%) had lymph nodes involvement.

Results. There were 2 postoperative deaths (4.8%) related to pneumonectomy and one death within 30 days for rapidly evolving disease; 4 patients (9.5%) had major postoperative complications that were medically treated. Five patients (12%) were operated on for recurrences on the residual lung. At the completion of the study, 12 patients were still alive, 8 without recurrences. The median survival was 6.5 months (range, 1 to 144 months); the 5-year survival was 16.8%.

Conclusions. Pneumonectomy should not be considered an absolute contraindication in patients with PM, but the poor outcome of our series suggests strict criteria of selection.  相似文献   

102.
103.
An important role of TNF interacting with TNFR2 has been shown in different models of ischemic, nephrotoxic and immune-mediated renal injury. To systematically evaluate the expression of TNFR2 in renal allograft rejection, we investigated human renal allograft biopsies and, in addition, established an experimental transplantation model in rats to verify the human data under standardized conditions.
The expression of TNFR2 was analyzed in 96 human renal allograft biopsies with different disease entities. In a 6-day and a 28-day experimental protocol, TNFR2 was examined in kidney specimens and in the urine of control, uni-nephrectomized and transplanted rats ± cyclosporine treatment (n = 114).
In human biopsies and in rat allografts on day 6 with acute allograft rejection, significantly elevated expression of TNFR2 was observed in tubular epithelial cells, podocytes, B cells and monocytes/macrophages. The expression level was associated with renal function. The TNFR2 expression level at day 28 was significantly lower compared to day 6.
TNFR2 is markedly upregulated both in human and experimental acute renal allograft rejection. Our data are robust and consistent between different species, suggesting a role for TNFR2 in the early course of rejection.  相似文献   
104.
105.
Accurate assessment of myocardial viability permits selection of patients who would benefit from myocardial revascularization. Currently, rest-redistribution thallium-201 scintigraphy and low-dose dobutamine echocardiography are among the most used techniques for the identification of viable myocardium. Thirty-one consecutive patients (all men, mean age 60NJ years) with chronic coronary artery disease and reduced left ventricular ejection fraction (31%lj%) were studied. Rest 201Tl single-photon emission tomography (SPET), low-dose dobutamine echocardiography and radionuclide angiography were performed before revascularization. Radionuclide angiography and echocardiography were repeated after revascularization. An a/dyskinetic segment was considered viable on 201Tl SPET when tracer uptake was >65%, while improvement on low-dose dobutamine echocardiography was considered a marker of viability. Increase in global ejection fraction was considered significant at ̓%. In identifying viable segments, rest 201Tl SPET showed higher sensitivity than low-dose dobutamine echocardiography (72% vs 53%, P<0.05), while specificity was not significantly different (86% vs 88%). In 17 patients, global ejection fraction increased ̓% (group 1) while in 14 it did not (group 2). A higher number of a/dyskinetic segments were viable on 201Tl SPET in group 1 than in group 2 (2.6ǃ.9 vs 0.6ǃ.2, P<0.005), while no significant differences were observed on low-dose dobutamine echocardiography (1.7ǃ.6 vs 1.1ǃ.6). A significant correlation was found between the number of a/dyskinetic segments viable on 201Tl SPET and post-revascularization changes in ejection fraction (r=0.52, P<0.05), but such a correlation was not observed for low-dose dobutamine echocardiography. Using as the cut-off the presence of at least one viable a/dyskinetic segment, rest 201Tl SPET had a higher sensitivity (82% vs 53%, P=0.07) and showed a trend towards higher accuracy and specificity (77% vs 58%, and 71% vs 64%, respectively) as compared with low-dose dobutamine echocardiography. In conclusion, these findings suggest that when severely reduced global function is present, rest 201Tl SPET evaluation of viability is more accurate than low-dose dobutamine echocardiography for the identification of patients who will benefit most from revascularization.  相似文献   
106.
PURPOSE: There is growing interest among urologists on the need for decreasing pain during transrectal ultrasound (TRUS) guided prostate biopsy. MATERIALS AND METHODS: We performed a systematic MEDLINE search of clinical trials of any kind of anesthesia, analgesia or sedation during TRUS guided prostate biopsy published since 2000. We critically analyzed the impact of pain and discomfort associated with the procedure, the described methods for evaluating it and the different techniques that have been described. RESULTS: There is strong evidence in the current literature that patient tolerance and comfort during TRUS guided prostate biopsy can be improved by anesthesia/analgesia. What remains is the need to urge all urologists to introduce it in clinical practice as a routine part of the procedure, whatever the biopsy scheme. CONCLUSIONS: Of the various options periprostatic anesthetic infiltration has been shown to be safe, easy to perform and highly effective. It should be considered the gold standard at the moment, even if the optimal technique remains to be established. Further studies addressing this issue are warranted.  相似文献   
107.
This study evaluated the diagnostic impact of using skeletal 18F-fluoride PET/CT on patients with painful bone metastases to schedule an early palliative radionuclide treatment. Methods: The skeletal involvement from prostate cancer metastases was assessed by both 99mTc-diphosphonate bone scan (BS) and 18F-fluoride PET/CT within four weeks in 24 patients (67.7 ± 5.1 years) suffering from a borderline degree of bone pain for which radionuclide palliation was not shortly planned for administration. The BS and 18F-fluoride PET/CT results were compared, assessing the number and extension of the skeletal sites involved. Afterward, the patients were randomly assigned either to the study group (N = 12) receiving radionuclide therapy (Samarium-153 EDTMP) or to the control group (N = 12) not receiving radionuclide therapy. The short-term results from the radionuclide palliation group (evaluated with a visual analogue scale) were compared with the controls. Results: Overall, at BS, 7.6 ± 1.4 sites were considered metastatic, involving at least 5 ± 1 body regions. At 18F-fluoride PET/CT, 116 ± 19 sites presented metastatic involvement with 12/12 body regions concerned. No differences were found in regards to either the number of metastatic sites or regions at both BS and 18F-fluoride PET/CT between the study group and controls (p = ns). At CT, 88 blastic metastases were identified, whereas 110 were mainly lytic. Most of mainly lytic lesions were not detectable at BS. The reduction in total discomfort and bone pain in the study group was significantly greater than in the controls (p < 0.0001). Conclusion: Sm-153 EDTMP therapy should be considered for patients with early bone pain from prostate cancer even if their BS only indicates a few metastases before the initiation of a severe pain syndrome. 18F-fluoride PET/CT may be helpful in deciding if the implementation of bone pain palliation using bone-seeking radionuclides at pain onset is necessary.  相似文献   
108.

Objectives

The major objective was to prospectively compare the grade of bowel distension obtained with four different computed tomography (CT) techniques dedicated for the examination of the small intestine (CT enteroclysis [CTE] and enterography [CTe]), of the colon (CT with water enema [CT-WE]), or both (CTe with water enema [CTe-WE]). The secondary objective was to assess patients’ tolerance toward each CT protocol.

Materials and methods

Recruitment was designed to obtain four groups of the same number of patients (30). Each group corresponded to a specific CT technique, for a total of 120 consecutive outpatients (65 male and 55 female, mean age 51.09 ± 13.36 years).CTE was performed after injection of methylcellulose through a nasojejunal tube, while in the CTe protocol a polyethylene glycol electrolyte solution was orally administered to patients prior to the CT acquisition. In the CT-WE protocol intraluminal contrast (water) was administered only by a rectal enema, while CTe-WE technique included both a rectal water enema and oral ingestion of neutral contrast material to obtain a simultaneous distension of small and large bowel.CT studies were reviewed in consensus by two gastrointestinal radiologists who performed a quantitative and qualitative analysis of bowel distension on a per segment basis. The presence and type of adverse effects were recorded.

Results

CTE provided the best distension of jejunal loops (median diameter 27 mm, range 17–32 mm) when compared to all the other techniques (p < 0.0001). The frequency of patients with an adequate distension of the terminal ileum was not significantly different among the four groups (p = 0.0608). At both quantitative and qualitative analysis CT-WE and CTe-WE determined a greater and more consistent luminal filling of the large intestine than that provided by both CTE and CTe (p < 0.0001 for all colonic segments). Adverse effects were more frequent in patients belonging to the CTE group (p < 0.0028).

Conclusions

CTE allows an optimal distension of jejunal loops, but it is the most uncomfortable CT protocol. When performing CT-WE, an adequate retrograde distension of the terminal ileum was provided in a particularly high percentage of patients. CTe-WE provides a simultaneous optimal distension of both small and large bowel.  相似文献   
109.

Background

Exercise and dipyridamole 99mTc-labeled methoxy isobutyl isonitrile (MIBI) myocardial scintigraphy have been widely used for the diagnosis of coronary artery disease (CAD). However, only limited data on adenosine 99mTc-labeled MIBI cardiac imaging are currently available. This study was designed to assess the accuracy of quantitative adenosinerest 99mTc-labeled MIBI tomography in the diagnosis and localization of CAD.

Methods and Results

Fifty-seven consecutive patients with suspected CAD who underwent coronary angiography and 22 normal volunteers were studied. All patients underwent 99mTc-labeled MIBI tomography after administration of adenosine (140 μg/kg intravenously for 6 minutes) and at rest. A total of 171 vascular coronary territories were analyzed quantitatively. All patients with CAD (≥50% luminal stenosis) (n=55) had abnormal 99mTc-labeled MIBI tomograms. The normalcy rate was 86% by quantitative analysis. Overall sensitivity, specificity, and diagnostic accuracy for detection of individual stenosed vessels were 84%, 87%, and 85%, respectively. In patients with one-vessel CAD (n=24), sensitivity and diagnostic accuracy in the detection of individual stenosed vessels were significantly (p<0.05) higher compared with patients with multivessel CAD (n=31). Moreover, 75% of patients with one-vessel disease showed a scintigraphic pattern characterized by the presence of perfusion defects in only one coronary artery territory, and 74% of patients with multivessel disease showed a scintigraphic pattern characterized by the presence of perfusion defects in two or more coronary artery territories. Sensitivity, specificity, and diagnostic accuracy for detecting individual diseased vessels were similar in patients without previous myocardial infarction (n=18) compared with those with previous myocardial infarction (n=39). In myocardial territories related to noninfarcted areas (n=124), sensitivity and specificity in the detection of stenosed vessels were 75% and 88%. In infarcted areas (n=47), sensitivity and specificity in the detection of stenosed vessels were 98% and 80% (differences not significant vs noninfarcted areas).

Conclusions

Adenosine-controlled coronary vasodilation combined with quantitative 99mTc-labeled MIBI tomography is accurate for identifying patients with CAD and localizing individual stenosed coronary arteries.  相似文献   
110.
To compare rest-injected thallium-201 (Tl) redistribution and resting technetium-99m methoxyisobutylisonitrile (99mTc-MIBI) myocardial uptake in chronic coronary artery disease (CAD), 15 patients with angiographically proven CAD and left ventricular (LV) dysfunction (ejection fraction 34%±9%) were studied. All patients underwent rest-redistribution Tl and resting 99mTc-MIBI cardiac imaging. Gated 99mTc-MIBI images were also acquired to assess regional LV wall motion (WM). Myocardial segments (n=225) were divided into three groups on the basis of the degree of coronary artery stenosis: group 1 (total occlusion, n=82), group 2 (50%–99% of stenosis, n=84) and group 3 (<50% of stenosis, n=59). WM was significantly worse in groups 1 and 2 compared to group 3 (P<0.001), but no difference was observed between groups 1 and 2. TI and 99mTc-MIBI uptake were significantly lower in groups 1 and 2 compared to group 3 (P < 0.001), and in group 1 compared to group 2 (P<0.001). When TI and 99mTc-MIBI uptake were directly compared, TI uptake was higher than 99mTc-MIBI uptake in group 1 (P<0.001), while no significant difference was observed in groups 2 and 3. Thus, both rest-injected TI redistribution and resting 99mTc-MIBI uptake reflected the severity of coronary artery stenosis in CAD. However, in myocardial segments with total coronary occlusion T1 uptake was significantly higher than 99mTc-MIBI uptake. Our data suggest that rest-injected Tl redistribution cardiac imaging may identify, more accurately than resting 99mTc-MIBI imaging, the presence of viable myocardium in chronic CAD, particularly when the coronary blood flow is severely impaired.  相似文献   
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