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21.
Meningiomas are the most common primary intracranial tumors. They are usually benign and slowly growing; however, they may show histologically malignant features categorizing them into grade II or III of World Health Organization (WHO) classification. Rhabdoid meningioma (RM) is an uncommon meningioma variant categorized as WHO grade III. The clinical course of RM is determined by local recurrences, invasion of adjacent brain and/or dura, widespread leptomeningeal dissemination, remote metastases and fatal clinical outcome. Herein we report a case with recurrent aggressive left occipital parasagittal region RM in which the patient initially declined radiation treatment. The tumor was resected four times in 5 years. Histopathological examination revealed a rhabdoid meningioma with metaplastic, papillary and chordoid differentiation. Six months after her fourth operation the patient died of progressive disease. RM is a rare subtype of malignant meningioma and the role of different adjuvant therapeutic options are still unknown. Clinical presentation, radiological features and pathologic findings of this uncommon tumor are discussed.  相似文献   
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BACKGROUND: The primary goal of ultrasonography (US) in the evaluation of a thyroid nodule is to determine its malignancy, although the diagnosis of a malignant nodule on the basis of US alone is nearly impossible. The aim of this prospective study was to evaluate the predictive value of sonographic features in the preoperative diagnosis of malignant thyroid nodules, and to determine the important features of sonography. METHODS: This prospective study included 550 consecutive patients with , thyroid nodules. Nodules were divided into two groups on the basis of pathological diagnosis: group 1 consisted of 1,633 nodules with a benign pathology, and group 2 consisted of 293 nodules with a malignant pathology. RESULTS: Microcalcifications, blurred nodular margins, and solid and hypoechoic appearance were more common in malignant nodules compared to benign nodules (89.1% versus 5%; 64.5% versus 4.7%; 81.6% versus 30.6% ; and 62.5% versus 43.1%, respectively; p < 0.001). There was a positive correlation between the detection of malignant thyroid nodules and microcalcification (rs = 0.791, p = 0.0001), blurred nodular margin (rs = 0.625, p = 0.0001), solid appearance (rs = 0.376, p = 0.0001), and hypoechoic appearance (rs = 0.141, p = 0.0001). Microcalcifications, blurred nodular margins, and solid and hypoechoic appearance were independent determinants of malignancy upon US examination of thyroid nodules (OR: 159, OR: 37, OR: 9.9, and OR: 2.2, respectively). CONCLUSION: Although we did not identify a single feature indicative of malignancy in the sonographic examination of nodules, microcalcification and blurred margin were the strongest correlates for malignancy.  相似文献   
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Objectives Although development of new treatment modalities limited digoxin usage, digoxin intoxication is still an important issue which could be easily overlooked. In this report we analyzed a case series definitively diagnosed as digoxin intoxication in the modern era. Methods We analyzed 71 patients hospitalized with digoxin intoxication confirmed by history, complaints, clinical and electrocardiograph (ECG) findings, and serum digoxin levels > 2.0 ng/mL, during a five year period. The demographic and clinical data, indications for digoxin use, digoxin dosage, concurrent medications, laboratory data, hospital monitoring, and ECG findings were obtained from all patients. Results Thirty-eight of 71 patients (53.5%) had symptoms of heart failure during admission or later. Sixty-four percent of patients were older than 75 years. The percentage of females was 67%. Atrial fibrillation, hypertension and gastrointestinal complaints were more frequent in the females (64% in females, 30% in males, P = 0.007; 81% in female, 52% in males, P = 0.01; 50% in female, 17.3% in males, P = 0.008, respectively). The mortality rate during the hospital course was 7%. Conclusion This report demonstrated the reduced mortality rates in patients with digoxin intoxication over the study period. Gastrointestinal complaints are the most common symptoms in this population.  相似文献   
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Background and objectives: Concern about primary fistula failure may contribute to the underuse of arteriovenous fistula. The objective of this study was to investigate the baseline clinical parameters associated with primary fistula success.Design, setting, participants, & measurements: Consecutive incident patients who commenced dialysis during a 28-mo period in a regional renal program were studied. Data on patient-related variables and on surgical approach (e.g., whether the surgeons routinely assess vessel size during the operation) were collected. Primary fistula success was defined as an arteriovenous fistula that was able to afford successful dialysis for 3 h with blood pump speed of ≥300 ml/min for three consecutive sessions.Results: A total of 205 (69%) patients had an AVF attempted as their first vascular access. The overall primary success rate was 64% and was similar for radiocephalic and brachiocephalic fistula. Logistic regression was done separately for patients with the two types of fistula because of the presence of statistical interaction. For radiocephalic fistula, male gender was the only parameter associated with primary fistula success (odds ratio 3.57; P = 0.01). The presence of comorbidity was not significantly associated with primary fistula failure.Conclusions: Despite significant patient comorbidity, there was a high primary fistula success rate among this incident hemodialysis cohort. Given that vessel size may be the ultimate determinant of fistula success, if surgeons assess vessel size perioperatively, then the presence of significant comorbidity might not preclude arteriovenous fistula from being attempted as the initial access.Given the well-documented advantages of arteriovenous fistula (AVF) over arteriovenous graft and central venous catheter (CVC), the current Kidney Disease Outcomes Quality Initiative (K/DOQI) guidelines suggest that AVF should be attempted as the initial vascular access in at least 50% of incident patients and that at least 40% of prevalent hemodialysis (HD) patients should undergo dialysis with an AVF (15). Despite these recommendations, it is clear that AVF are underused in many centers in North America, especially when compared with European centers (6,7). Recent data suggest that only 32% of prevalent US HD patients undergo dialysis with an AVF (8). In Canada, AVF are used by 53% of prevalent and only 26% of incident HD patients (7).One of the fears that may reduce the use of AVF is the high primary fistula failure rate (i.e., failure of AVF to mature) (9). Identifying risk factors that contribute to primary fistula failure may help clinicians and patients make an informed decision as to for whom to attempt an AVF. Only a few studies have prospectively examined the risk factors associated with primary fistula failure, which has been reported in 20 to 50% of patients (912).Most studies that have evaluated factors that are associated with primary fistula failure have typically used a retrospective design. For instance, Miller et al. (10) reported higher primary fistula failure rate in older and female patients with diabetes, although small numbers and a highly selected patient population limit the generalizability of these results. Feldman et al. (13) published data from a larger cohort (348 patients), reporting a primary success rate of 54%. Preexisting cerebrovascular disease, older age, and commencement of dialysis before access creation were noted to be associated with higher primary fistula failure in their study. Ravani et al. (11) noted that cardiovascular disease and late referral to nephrologists were associated with lower primary AVF success in patients from northern Italy.More recently, Lok et al. (14) studied a cohort of 422 HD patients who were undergoing their first AVF placement to identify preoperative clinical characteristics that are predictive of fistula failure to mature and to use this information to develop a prediction rule to estimate the risk for fistula failure to mature. This prediction rule was validated in an external data set from five North American centers. Age, peripheral vascular disease, coronary artery disease, and white race all were associated with fistula failure to mature in their study; however, in this and the previously mentioned studies, it is not clear whether there was any consistent surgical assessment performed perioperatively to guide fistula placement; as such, the results may not be applicable to programs that use pre- or intraoperative surgical assessment to guide fistula placement.Given these uncertainties, we sought to determine the association of various baseline clinical parameters with primary fistula success in a cohort that consisted of all incident dialysis patients between July 1, 1999, and November 1, 2001, in Calgary, Alberta, Canada, the majority of whom had an indirect assessment of vessel diameter intraoperatively to guide the location of fistula placement.  相似文献   
27.
Prayer is one kind of worship that is composed of repetitive action during praying in Islam. The prayer is performed five times a day, every Friday, bairams and death ceremonies. The aim of this study is to search the role of this repetitive action on knee, hip osteoarthritis and osteoporosis. Forty-six patients who had been performing the prayer at least for 10 years, and 40 patients who had not performed the prayer, were included in this prospective study. Each patient was evaluated with standard questionnaire form, joint examination was done and various laboratory parameters were studied. Anterior–posterior radiography of the pelvis and weight-bearing knees of each patient were examined. Each film was evaluated by two investigators separately and first scored by using Kellgren and Lawrence (K&L) scale, then the width of the joint space of hips and knees were measured directly using a steel ruler and recorded to the nearest half millimeter. Bone mineral density (BMD) of lumbar spine and femur was measured. Patients having Heberden’s nodes, Bouchard’s nodes, and carpometacarpal disease were frequent in worshiper group. Joint space width measurements and assessment according to K&L scale did not differ between worshipers and non-worshipers. BMD of lumbar spine was decreased in worshipers and also decreased with patients having Heberden’s nodes, Bouchard’s nodes, female gender and age. Prayer has no effect on knee and hip osteoarthritis, and may be related with hand osteoarthritis. It seems to have negative effect on lumbar BMD, but further investigations are needed.  相似文献   
28.
Objective: The role of coronary artery bypass grafting (CABG) in patients with severe left ventricular dysfunction was evaluated. Methods: Two hundred and twelve patients (152 men, 60 women; age 35 to 82, mean 55) with ejection fraction (EF) of less than 30% underwent CABG between January 1996 and February 2001 by a single surgeon (SA). They compromised of 12% of 1759 patients operated on in this period. EF ranged from 17% to 30% (mean 25%). Preoperatively 68% had congestive heart failure and 72% had severe angina (CCS 3 or 4). A left main lesion was found in 26% of the cases. The mean number of grafts was 3.18 per patient. The left internal mammary artery (LIMA) was used on 107 patients (50.4%). Preoperative intraaortic balloon pump (IABP) was used on 32 patients (15%). Endarterectomy was performed on 53 patients (25%). The patients were followed for up to 58 months (mean 28.7). Results: Twelve patients died in hospital (5.6%). Survival was 94%, 87%, 80% and 73% at 1, 2, 3 and 4 years respectively. Among the preoperative variables survival was negatively affected by chronic renal failure, older age, congestive heart failure, elevated pulmonary artery pressure and recent myocardial infarction, by means of multivariate analysis. Preoperative IABP support improved the operative mortality significantly (P=0.002). Use of LIMA did not have any influence on survival. Conclusion: CABG on patients with poor left ventricular function: (1) Can be performed with an acceptable mortality. (2) Mid term results are encouraging. (3) Preoperative IABP support improves the chance of survival.  相似文献   
29.
Isolated TSH deficiency is a rare cause of congenital hypothyroidism. We here report four children from two consanguineous Turkish families with isolated TSH deficiency. Affected children who were screened at newborn age had an unremarkable TSH result and a low serum TSH level at diagnosis. Age at diagnosis and clinical phenotype were variable. All affected children carried an identical homozygous splice site mutation (IVS2 + 5 G--> A) in the TSHbeta gene. This mutation leads to skipping of exon 2 and a loss of the translational start codon without ability to produce a TSH-like protein. However, using specific monoclonal antibodies, we detected a very low concentration of authentic, heterodimeric TSH in serum, indicating the production of a small amount of correctly spliced TSH mRNA. By genotyping all family members with polymorphic markers at the TSHbeta locus, we show that the mutation arose on a common ancestral haplotype in three unrelated Turkish families indicating a founder mutation in the Turkish population. These results suggest that this TSHbeta mutation is among the more common TSHbeta gene mutations and stress the need for a biochemical and molecular genetic workup in children with symptoms suggestive of congenital hypothyroidism, even when the neonatal TSH screening is normal.  相似文献   
30.
In human endometriotic stromal cells, markedly high levels of aromatase P450 (P450arom) mRNA and promoter II activity are present and can be vigorously stimulated by PGE(2) via a cAMP-dependent pathway to give rise to physiologically significant estrogen biosynthesis. Stromal cells of eutopic endometrium, on the other hand, do not express sufficient levels of P450arom for detectable enzyme activity. Because P450arom is up-regulated in the ovaries of CCAAT/enhancer binding protein (C/EBP) beta knockout mice and activation of the ovarian-type P450arom promoter (II) is responsible for aberrant P450arom expression in endometriosis, we sought here to evaluate the possible roles of C/EBP isoforms in the regulation of P450arom expression in endometriotic vs. eutopic endometrial stromal cells. We previously found that the -517-bp flanking region of promoter II contained the critical cis-acting elements for baseline and cAMP (analog)-induced activity. In this study, we disrupted several potential sequences and found that mutations of a -211/-197-bp cAMP-response element (CRE) and a -317/-304-bp C/EBP binding site abolished both baseline and cAMP-induced promoter II activity. Ectopic expression of C/EBPalpha increased both baseline and cAMP-dependent promoter II activity significantly in endometriotic cells, whereas ectopic expression of C/EBPbeta or C/EBPdelta abolished promoter II activity in both untreated and cAMP-treated endometriotic stromal cells. Comparable changes in promoter II activity were observed using endometrial stromal cells, which showed, however, seemingly diminished levels of baseline and cAMP-induced promoter II activity in comparison with endometriotic cells. EMSA using a probe containing the critical -317/-304-bp C/EBP site upstream of promoter II demonstrated a distinct DNA-protein complex in endometriotic, but not in endometrial stromal cells. This specific complex, however, could not be altered using antibodies against C/EBPalpha, -beta, or -delta. Because CRE is another potential DNA motif that can bind C/EBP isoforms, we next used EMSA using a probe containing the -211/-197-bp CRE and demonstrated that specific DNA-protein complexes contained C/EBPalpha but not C/EBPbeta or C/EBPdelta in endometriotic stromal cells. In contrast, C/EBPbeta and C/EBPdelta but not C/EBPalpha were detected in DNA-protein complexes using nuclear extracts from endometrial stromal cells. Western blotting and immunohistochemistry demonstrated expression of C/EBPalpha, -beta, and -delta in human endometriotic and endometrial stroma and epithelium. Intriguingly, C/EBPbeta was expressed at increased levels in stromal cells of human eutopic endometrium compared with simultaneously biopsied endometriotic tissues. We conclude that both -317/-304 and -211/-197-bp elements in promoter II are critical for the robust cAMP-dependent induction in endometriosis. C/EBPalpha up-regulates, whereas C/EBPbeta and C/EBPdelta inhibit P450arom promoter activity via binding primarily to the -211/-197-bp CRE under in vitro conditions. In vivo down-regulation of C/EBPbeta in endometriotic stromal cells and its up-regulation in endometrial stromal cells may in part account for the induction of P450arom expression in endometriosis and its inhibition in endometrium.  相似文献   
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