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91.
BACKGROUND: Adrenal incidentaloma presents a frequent finding in patients with a history of malignancy. This study was carried out to determine whether imaging techniques can discriminate between a malignant and a benign adrenal tumor and subsequently select candidates for adrenal surgery. METHODS: Beginning in July 1995, oncologic patients with adrenal incidentaloma underwent abdominal ultrasonography, computed tomography (CT), magnetic resonance imaging (MRI), and [ 18 ]fluoro-2-deoxy-D-glucose positron emission tomography (18-FDG-PET). Consecutively in all patients adrenalectomy was performed. Histologic findings were compared with the imaging results. RESULTS: In 42 patients, 33 to 79 years old (mean age, 58 years), 44 adrenal lesions were detectable. Two patients presented with bilateral adrenal masses. At operation, 43 adrenal resections and 3 biopsies were performed. Histologic examination revealed 31 metastases (71%) and 13 adrenal adenomas (29%). In metastases the sensitivity of ultrasonography, CT, MRI, and 18-FDG-PET was 66%, 81%, 100%, and 100%, respectively. For adrenal adenoma, the sensitivity of ultrasonography, CT, MRI, and 18-FDG-PET was 46%, 39%, 100%, and 54%, respectively. CONCLUSIONS: In oncologic patients with indeterminate adrenal tumors MRI and 18-FDG-PET provide accurate differentiation between metastases and benign adenomas. Positive results of these 2 imaging modalities are highly suggestive for metastatic disease. In cases of negative MRI and 18-FDG-PET results the adrenal lesion corresponds to a benign adenoma that needs no surgical intervention.  相似文献   
92.
Blocking the CD40‐CD154 pathway prevents allograft rejection and induces donor‐specific tolerance in various experimental models. However, the translation to clinical studies has been hampered by unexpected thromboembolic complications of CD154‐blocking antibodies. Thus, blocking CD40 instead is now considered as an alternative strategy. Here, we evaluated the role of donor CD40 in allospecific T‐cell responses in vitro and in an in vivo model for renal transplantation. Fully MHC‐mismatched allografts from CD40‐deficient donors displayed better renal function than wild type. These functional data correlated with a lower level of apoptosis in renal tubular epithelial cells and higher expression of PD‐L1, which is most probably because of a reduced Th17 response in recipients of a CD40‐deficient donor. This hypothesis was supported in vitro, where donor CD40 expression was important for the induction of direct allospecific T‐cell responses. Especially the induction of Th17 cells was critically dependent on donor CD40. IL‐17A in conjunction with interferon‐γ in turn rendered renal tubular epithelial cells to a more costimulatory state by upregulating CD40 and downregulating PD‐L1 expression. In conclusion, CD40 blockade not only reduces the allospecific T‐cell responses, but might also lead to protection of tubular epithelium from apoptosis and thereby preserve kidney allograft function.  相似文献   
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Anemia is a common complication of chronic kidney disease (CKD) in predialysis stage. Iron deficiency is more common than in normal patients and plays a key role in the genesis of anemia. Its correction avoids the use of erythropoiesis stimulating agents (ESA) or reduces their dosage. Treatment with oral iron is often poorly tolerated and ineffective, necessitating the use of intravenous iron. New forms of injectable iron allow the use of high doses and correct iron deficiency in a single administration with consequent preservation of venous capital and lower costs. We studied the effectiveness of iron dextran of low molecular weight (LMWID) in high doses to correct iron deficiency and treat anemia in predialysis CKD patients. Twenty-nine doses of 500 to 1600 mg were administered to 25 patients followed for CKD (GFR between 60 and 10 ml/min per 1.73 m2), selected on biological criteria of iron deficiency defined by a ratio of transferrin saturation (TSAT) < 20% and/or serum ferritin of less than 100 μg/L. Patients received treatment by ESA in 16 cases out of 29. One month after treatment, hemoglobin (Hb) increased significantly (11.4 ± 1.6 vs 10.4 ± 1.4 g/dL, P = 0.0003) along with a significant increase in TSAT (21.3 ± 7.3 vs 13.3 ± 3.8%, P = 0.000003) and serum ferritin (286 ± 253 vs 91 ± 60 μg/L, P = 0.00005). Six patients had a serum ferritin greater than 500 μg/L after treatment, which may put them at risk of iron overload. Their serum ferritin was higher than the rest of the population before treatment, while the TSAT was no different, reflecting a functional deficiency. Their hemoglobin did not increase after treatment in contrast to the rest of the population suggesting the unavailability of iron for erythropoiesis with accumulation in the reticuloendothelial system. Renal function did not change significantly and there were no cases of acute renal failure. No immediate side effect was observed. Three patients presented delayed reactions to such self-limiting myalgia and arthralgia. No venous inflammatory reaction was noted. The administration of high doses of LMWID is effective in treating anemia of CKD in the predialysis stage with a satisfactory tolerance, without affecting kidney function and helps preserve the venous capital. It should be reserved for patients whose serum ferritin is less than or equal to 150 μg/L.  相似文献   
96.

Background

To evaluate the haemodynamic changes induced by flow diversion treatment in cerebral aneurysms, resulting in thrombosis or persisting aneurysm patency over time.

Method

Eight patients with aneurysms at the para-ophthalmic segment of the internal carotid artery were treated by flow diversion only. The clinical follow-up ranged between 6?days and 12?months. Computational fluid dynamics (CFD) analysis of pre- and post-treatment conditions was performed in all cases. True geometric models of the flow diverter were created and placed over the neck of the aneurysms by using a virtual stent-deployment technique, and the device was simulated as a true physical barrier. Pre- and post-treatment haemodynamics were compared, including mean and maximal velocities, wall-shear stress (WSS) and intra-aneurysmal flow patterns. The CFD study results were then correlated to angiographic follow-up studies.

Results

Mean intra-aneurysmal flow velocities and WSS were significantly reduced in all aneurysms. Changes in flow patterns were recorded in only one case. Seven of eight aneurysms showed complete occlusion during the follow-up. One aneurysm remaining patent after 1?year showed no change in flow patterns. One aneurysm rupturing 5?days after treatment showed also no change in flow pattern, and no change in the maximal inflow velocity.

Conclusions

Relative flow velocity and WSS reduction in and of itself may result in aneurysm thrombosis in the majority of cases. Flow reductions under aneurysm–specific thresholds may, however, be the reason why some aneurysms remain completely or partially patent after flow diversion.  相似文献   
97.

Purpose  

Bone defects resulting from tumour resection or curettage are most commonly reconstructed with autologous bone graft which is associated with limited availability and donor site morbidity. Recent research has focussed on synthetic biomaterials as bone graft substitutes. The aim of this study was to assess the safety and efficiency of a bone substitute as an alternative for autologous bone in the treatment of benign bone tumours and tumour-like lesions.  相似文献   
98.

Background

Ligament balancing is considered a prerequisite for good function and survival in total knee arthroplasty (TKA). However, there is no consensus on how to measure ligament balance intra-operatively and the degree of stability obtained after different balancing techniques is not clarified.

Purpose

This study presents a new method to measure ligament balancing in TKA and reports on the results of a try-out of this method and its inter-observer reliability.

Methods

After the implantation of the prosthesis, spatulas of different thickness were used to measure medial and lateral condylar lift-off in flexion and extension in 70 ligament-balanced knees and in 30 knees were ligament balancing was considered unnecessary. Inter-observer reliability for the new method was estimated and the degree of medial–lateral symmetry in extension and in flexion, and the equality of the extension gaps and flexion gaps were calculated.

Results

The method was feasible in all operated knees, and found to be very reliable (intraclass correlation coefficient?=?0.88). We found no statistically significant difference in condylar lift-off between the ligament-balanced and the non ligament-balanced group, however, there was a tendency to more outliers in flexion in the ligament-balanced group.

Conclusions

Our method for measuring ligament balance is reliable and provides valuable information in assessing laxity intra-operatively. This method may be a useful tool in further research on the relationship between ligament balance, function and survival of TKA.  相似文献   
99.
Chronic heart failure is a common disorder associated with unacceptably high mortality rates. Chronic renal disease and anemia are two important comorbidities that significantly influence morbidity and mortality in patients with chronic heart failure (CHF). Progress in CHF again may cause worsening of kidney function and anemia. To describe this vicious cycle, the term cardio-renal anemia syndrome has been suggested. Iron deficiency is part of the pathophysiology of anemia in both CHF and chronic kidney disease, which makes it an interesting target for treatment of anemia in cardio-renal anemia syndrome. Recently, studies have highlighted the potential clinical benefits of treating iron deficiency in patients with CHF, even if these patients are nonanemic. This article summarizes studies investigating the influence of iron deficiency with or without anemia in chronic kidney disease and CHF and gives an overview of preparations of intravenous iron currently available.  相似文献   
100.
Introduction The purpose of the study was to determine the distribution and number of nerves inside the infrapatellar fat pad and the adjacent synovium, in particular with regards to nociceptive substance-P nerves.Materials and methods The infrapatellar fat pad of the knee was resected from 21 patients (4 male, 17 female, mean age 69 years) during the course of standard total knee arthroplasty operations performed in our clinic. The fat pad was dissected into five standardized segments, fixed in formalin and embedded in paraffin. Immunohistochemical techniques using antibodies against S-100 protein and substance-P (SP) were employed to determine and specify the nerves.Results Studying all the detectable nerves present in 50 observation fields (200-fold magnification), we found an average of 106 S-100 versus 25 SP nerves (24%) in the synovium and 27 S-100- versus 7 SP nerves (26%) in the interior of the fat pad. The total nerve count was significantly ( P <0.001) higher in the synovium than in the fat pad for both marker types. The number of S-100 nerves was significantly ( P <0.05) higher in the central and lateral segments of the fat pad, while SP nerves were equally distributed throughout all segments of the fat-pad. SP nerves were significantly more frequently associated with blood vessels inside the fat pad (43%, P <0.05) than in the synovial tissue (28%).Conclusion The occurrence and distribution of SP nerves inside the infrapatellar fat pad suggest a nociceptive function and a neurohistological role in anterior knee pain syndrome. The data support the hypothesis that a neurogenous infection of the infrapatellar fat pad could contribute to anterior knee pain syndrome.  相似文献   
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