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81.
BACKGROUND: Aneurysmal bone cysts (ABCs) are benign lesions that are usually treated with intralesional procedures. The clinical behavior of ABCs is reported to be more aggressive in younger patients, with high recurrence rates after surgical treatment by several authors. The purpose of this study was to review longitudinally the demographic data and outcome of current surgical techniques in children with ABC treated at a single institution and to determine the possible risk factors for recurrence, which may be detected at initial examination, including age, presenting complaint, and radiological characteristics. METHODS: The authors performed a retrospective, pediatric population-based (< or =16 years) analysis of 56 cases of ABCs with more than 2 years' follow-up. The subjects were studied and classified on the basis of their age group (< or =5, 5-10, and >10 years of age). The possible risk factors for recurrence were analyzed initially with Student t test and Pearson chi2 test, then a logistic regression analysis model was used for multivariate analysis. RESULTS: Nine patients were younger than 5 years, 17 were between 5 and 10 years old, and 30 were older than 10 years. The most frequent location of the lesion was the humerus (11 cases) followed by proximal femur and fibula. Curettage was the most common treatment modality followed by resection. Recurrence of the lesion occurred in 5 children in the younger age group and in 4 children in the older age group. The difference in persistence or recurrence rates based on age (< or =5 years) and previous surgery was statistically significant. In addition, we have found no significant implication of physeal contact and size of the lesion on recurrence. CONCLUSIONS: The recurrence rates of primary ABC seemed to be higher in younger children. Considering the high cure rates with intralesional procedures even after recurrence, we suggest less aggressive intralesional procedures even in patients with mentioned risk factors; however, the patients' family should be informed about the high probability of recurrence.  相似文献   
82.
Data regarding cardiovascular risk in subjects with non-functioning adrenal adenoma are limited. The objectives of this study are to investigate carotid intima media thickness (IMT) as an indicator of atherosclerosis in subjects with non-functioning adrenal incidentaloma (AI) and to evaluate the factors that could be associated with IMT. Forty-nine subjects without findings of hypercortisolism or other adrenal gland disorders, 34 body mass index (BMI)-unmatched controls (C) and 18 BMI-matched controls (BC) were enrolled. Participants underwent hormonal evaluation including morning cortisol, adrenocorticotrophic hormone (ACTH), post dexamethasone suppression test cortisol (DST), dehydroepiandrosterone sulfate (DHEAS), and urinary free cortisol. Anthropometric and metabolic parameters and carotid IMT were measured. AI group had increased BMI, blood pressure, waist circumference, post DST cortisol, uric acid, and homeostasis model assessment (HOMA) levels when compared with C. Blood pressure, uric acid and, post DST cortisol remained significantly elevated in AI versus BC. Average IMT was increased significantly in AI versus C (0.74 mm vs. 0.68 mm, P = 0.029) and insignificantly elevated in AI versus BC (0.74 mm vs. 0.67 mm, P = 0.086). In all participants, IMT was correlated with age, BMI, HOMA, waist circumference, morning cortisol, and uric acid. Morning cortisol was independently associated with HOMA levels in both AI group and all participants. Increased IMT in non-functioning AI was a consequence of insulin resistant state associated with subtle cortisol autonomy rather than a direct effect of cortisol. The correlation between morning cortisol and IMT may be associated with the effect of hypothalamus–pituitary–adrenal axis disturbances on vasculature.  相似文献   
83.
Complex regional pain syndrome type I (CRPS I) or reflex sympathetic dystrophy (RSD) is a painful and disabling neuropathic pain syndrome. We report a case of a patient who has experienced CRPS I four times with an unidentified cause for all recurrences. The patient responded well to a combination of physiotherapy and intravenous regional sympathetic block in the first two attacks, but not in the fourth one. Gabapentin was effective in the last two attacks. Gabapentin was gradually discontinued 12 months after the last attack and no other recurrence was observed for a follow-up period of 9 months. This case suggests that gabapentin might be considered in the treatment and prevention of CRPS I.  相似文献   
84.
Muscle herniation is a focal protrusion of muscle tissue through a defect in the deep fascial layer. Anterior tibial muscle is the most commonly affected muscle of the lower extremities because its fascia is the most vulnerable to trauma. Clinically it is characterized by asymptomatic or painful, skin‐coloured, soft, subcutaneous nodules of various size depending on the position. The diagnosis is usually made clinically based on its typical manifestations, but ultrasonographic examination is useful for detecting the fascial defect and excluding other conditions caused by soft tissue tumours such as lipomas, angiolipomas, fibromas, scwhannomas or varicosities. Although this entity is not rare, it has been less well documented in the dermatological literature. We report a case of bilateral tibialis anterior muscle herniation mimicking a soft tissue tumour in a young amateur football player.  相似文献   
85.
EAT is a new index of cardiac and visceral obesity. Waist circumference (WC) measurement is not fully reliable in the determination of visceral adipose tissue (VAT), especially in elderly individuals. Studies on the reflection of the intra-abdominal fat mass by the EAT mass surrounding the heart were performed. Our purpose in this study was to determine the relation between the MS criteria and EAT in MS cases and especially to compare anthropometric measures between non-geriatric patients under the age of 65, and geriatric ones over the age of 65 years. The study was performed during the years 2008 and 2009 on 120 cases; 66.7% of them were under the age of 65 and 33.3% of the cases were 65-year old or older. All of the patients were diagnosed as MS by the International Diabetes Federation (IDF) criteria. They were randomized as per the application order and included to the study. Each subject underwent transthoracic two-dimensional (2D) guided M-mode echocardiogram. We measured epicardial fat thickness on the 1/3 section close to the ventricle basis adjacent to the free wall of right ventricle from both the parasternal long axis (LA) and parasternal short axis (SA) views. Multiple regression analysis showed that WC, systolic blood pressure (SBP) and age were the strongest independent variables correlated with EAT (p < 0.001). We also determined a significant correlation between low-density lipoprotein-cholesterol (LDL-C) and EAT (p < 0.05). Our data show that EAT-measurement by echocardiography is an efficient method in determination of visceral adiposity and shall be taken into consideration especially when advanced age groups are in question.  相似文献   
86.
Recent publications suggest the utility of temozolomide (TMZ) in the management of aggressive pituitary adenomas and carcinomas, resistant to conventional treatments. The response to TMZ is inversely correlated with tumoral expression of O-6 methylguanine DNA methyl transferase (MGMT). Therefore, we aimed to assess MGMT immunoexpression in pure GH-secreting pituitary adenomas, in an effort to predict the likelihood of response to TMZ, and to correlate MGMT immunoexpression with Ki-67 LI and cytokeratin (CK) distribution pattern. Our material consisted of 36 GH-secreting pituitary adenomas (21 female,15 male, mean age 42.5±10.5), operated at our center between 2003 and 2010. Immunostaining for MGMT, Ki-67, and CK was performed using avidin-biotin-peroxidase complex method. Immunoreactivity for MGMT and Ki-67 was evaluated microscopically and recorded as percentages of positive nuclear immunostaining. CK distribution pattern was also evaluated microscopically and assoreted into dot-like and nondot-like pattern subtypes. MGMT immunoexpression scored as 0=none, 1=<10%, 2=<25%, 3=<50%, and 4=>50%. Staining for MGMT was <10% (score 1) in 30 (83.3%), 10-25% (score 2) in 3 (8.3%), 25-50% (score 3) in 2 (5.6%) and >50% (score 4) in 1 (2.8%) of the tumors, respectively. There was no correlation between Ki-67 LI and CK distribution pattern with MGMT immunoreactivity (P>0.05). Data from the current study suggest a large proportion of GH-secreting adenomas, including those with dot-like CK distribution pattern and high Ki-67 LI, demonstrate negative/low MGMT immunoreactivity and could be treated with TMZ, if conventional treatment fails.  相似文献   
87.
Paraganglioma affecting the cauda equina region is very rare and can be misinterpreted as an ependymoma which is more common at this site. A 38-year-old woman with a paraganglioma in the cauda equina is presented. MRI revealed a well-circumscribed, intradural, extramedullary tumor nodule with the dimensions of 2.5x1x1 cm. The patient underwent L3 laminectomy and total excision of the tumor. The tumor was diagnosed as ependymoma and the patient was decided to undergo adjuvant radiotherapy. The patient applied to our medical center for a second opinion. Histopathologically, her tumor was found to be a paraganglioma with ependymal features. Therefore no adjuvant therapy was applied. There is no evidence of recurrence or metastases for 15 months after her operation. Paraganglioma in the cauda equina/ filum terminale is very rare and can be misdiagnosed as ependymoma especially when it exhibits ependymoma-like histology. This rare form of paraganglioma behaves like a WHO grade I tumor of CNS like classic paraganglioma. No recurrence or metastasis is expected when it is totally resected. Morphology can be misleading hence immunohistochemistry and/or ultrastructural study is necessary for correct diagnosis.  相似文献   
88.
89.
Whether testicular toxicity is mediated by matrix metalloproteinases (MMPs) is an important question that has not been examined. This study investigated the suppressive effect of curcumin and caffeic acid phenethyl ester (CAPE) on oxidative stress, apoptosis, and whether MMPs mediate doxorubicin (DOX)-induced testicular injury. Male rats were randomly divided into eight groups (n = 8 per group). The groups were as follows: sham, dimethyl sulphoxide (100 µL), DOX (3 mg/kg), CAPE (2.68 mg/kg), curcumin (30 mg/kg), DOX+CAPE (3 mg/kg DOX and 2.68 mg/kg CAPE), DOX+curcumin (3 mg/kg DOX and 30 mg/kg curcumin) and DOX+CAPE+curcumin (3 mg/kg DOX, 2.68 mg/kg CAPE and 30 mg/kg curcumin). Injections were administered daily for 21 days. The oxidative stress, MMPs, proinflammatory cytokines and apoptotic markers in the DOX group were higher than the sham group (p < .05); these measures were lower in the groups treated with CAPE and curcumin together with DOX compared with the DOX group (p < .05). The results showed that MMPs mediated DOX-induced testicular injury, but CAPE and especially curcumin suppressed testis injury and cell apoptosis by suppressing DOX-induced increases in MMPs, oxidative stress and proinflammatory cytokines. However, curcumin exhibited more pronounced effects than CAPE in terms of all studied parameters.  相似文献   
90.
The performance of bone tissue in the presence of flaws is a highly remarkable one. Bone tissue is the outcome of an adaptive evolutionary process; thus, insight into the mechanisms by which it fails would provide valuable information not only for development of mechanically superior biomimetic materials but also for development of treatment modalities to prevent debilitating bone fractures. Clinically, fractures of skeletal organs occur as a result of aging, disease, overuse, and trauma. Fracture mechanics, a sub-discipline of solid mechanics that investigates the performance of cracked materials, has been employed extensively in characterizing the mechanisms by which bone tissue fractures. At present the fracture mechanisms at the macroscale are better characterized than at the microscale. On the other hand, a mechanistic understanding of damage evolution at the submicroscopic scale is largely limited to postulations with little experimental insight. The challenge of skeletal fragility will be dealt with more efficiently with deeper understanding of the fracture process at each hierarchical size scale. The most recent review on this subject matter was a decade ago, and there have been numerous developments in the fracture mechanics of bone since then. This review recaps the existing literature with an emphasis on the hierarchical nature of the fracture process in bone, entailing the supramolecular, microscopic, and macroscopic scales.  相似文献   
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