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A desmoplastic variant of ameloblastoma with osteoplasia in the stroma is reported. This tumour presented in the canine/premolar region of the left maxilla of a 31-year-old woman. It was treated by partial hemimaxillectomy and immediate reconstruction with a non-vascularised iliac graft. The location of this lesion, its histology and radiological features differ from those of the conventional ameloblastoma. The behaviour and prognosis of the desmoplastic ameloblastoma (DA) cannot at this stage be predicted due to the small number of cases that have been reported and a lack of long-term follow-up. To our knowledge this is the first documentation of the CT and MRI features of desmoplastic ameloblastoma with pathologic correlation.  相似文献   
23.
OBJECTIVE: To identify the independent and differential diagnostic and symptom correlates of suicidal ideation and suicide attempts and determine whether there are gender- and age-specific diagnostic profiles. METHOD: The relationships between suicidal ideation, suicide attempts, and psychiatric disorders were examined among 1,285 randomly selected children and adolescents, aged 9 to 17 years, of whom 42 had attempted suicide and 67 had expressed suicidal ideation only. Youths and their parents were interviewed as part of the Methods for the Epidemiology of Child and Adolescent Mental Disorders (MECA) Study, using the Diagnostic Interview Schedule for Children Version 2.3 (DISC-2.3). RESULTS: Logistic regression analyses indicated that mood, anxiety, and substance abuse/dependence disorders independently increased the risk of suicide attempts, after controlling for sociodemographic characteristics. There was no significant independent contribution of disruptive disorders to suicide attempts, although its association with suicidal ideation was significant. Substance abuse/dependence independently differentiated suicide attempters from ideators. Noncriterion symptoms that remained significant predictors of suicide risk, after adjusting for psychiatric disorder, included panic attacks and aggressiveness. Perfectionism did not significantly increase suicide risk after adjusting for psychiatric disorder. The association of specific disorders and noncriterion symptoms with suicidality varied as a function of gender and age. CONCLUSION: A monolithic diagnostic risk profile for suicidality, ignoring gender- and age-specific risks, is inadequate. The contribution of substance abuse/dependence in the escalation from suicidal thoughts to suicide attempts is underscored.  相似文献   
24.
This study was carried out to assess the frequency of ductal carcinoma in situ (DCIS) occurring within and surrounding grade 3 invasive tumours and the effect of its detection on size and nodal stage of invasive carcinomas at mammographic detection. Grade 3 tumours with either no associated DCIS or DCIS only within the invasive component were significantly larger in size than tumours with surrounding DCIS (P < 0.02) and were less likely to be under or equal to 10 mm in size (0% or 13% vs 30% respectively, P < 0.02). Tumours with mammographic calcification were more likely to be less than or equal to 10 mm in size than non-calcific tumours (32% vs 11% respectively, P < 0.05). This was because of the high frequency of tumours less than or equal to 10 mm in size in the linear/branching calcification group. Tumours showing calcification without a mass also appear to be a group with good prognostic features, with a mean size of 13 mm, 33% being 10 mm or less in size and only 17% being node positive. We have found that the presence of surrounding DCIS enables earlier detection of grade 3 invasive carcinomas because of the presence of mammographically visible calcification. Detection of calcification suggestive of DCIS should remain an important part of mammographic screening.  相似文献   
25.
A 56-year-old woman was admitted to our hospital with the chief complaint of left back pain. We detected left pleural effusion on chest X-ray and performed chest drainage. No malignant cells were detected in the effusion. Chest CT demonstrated a tumor shadow over the left diaphragm and left pleural effusion 6 months later. She underwent en bloc resection of the tumor and left diaphragm. Histological evaluation revealed malignant fibrous histiocytoma (MFH). Recurrent tumors were found in the abdomen 8 months after the operation, and she underwent resection of the abdominal recurrent tumors. Histological evaluation of the recurrent tumors also showed MFH. The patient died 28 months after the first operation.  相似文献   
26.
The concentration of the tumor marker CA 19-9 is influenced by the patient's secretor status and Lewis genotype. The aim of this study was to establish novel reference intervals for CA 19-9 in serum based on secretor and Lewis genotypes, to investigate the biological variation of CA 19-9, and to evaluate the utility of Lewis and secretor genotyping on a group of individuals with serologically defined Lewis phenotypes. CA 19-9 was measured in serum of 500 healthy individuals. Secretor and Lewis genotypes were determined by sequencing and PCR-cleavage methods. Significant differences were found between subgroups with different Lewis and secretor genotypes. Genotype-based reference intervals for CA 19-9 are presented. The upper reference limit for all individuals was 28.7 kilounits/L; for secretors and nonsecretors, the upper reference limits were 12.4 and 61.2 kilounits/L, respectively. The analytical imprecision (CVA) was 9.8%, the within-subject variability (CVI) was 15.8%, and the between-subject variability (CVG) was 102.2%. Good agreement was found between Lewis and secretor genotyping and conventional blood grouping. Genotype-based reference intervals may be a way to increase the clinical utility of CA 19-9. On the basis of the calculation of a critical difference for sequential values (significant at P 相似文献   
27.
An evaluation was done of respiratory failure in 149 children aged 3 to 15 presenting with funnel-shaped chest deformity (FCD). An original classification is suggested of degree of respiratory failure in FCD in children. Based on the index assessment of clinical and functional parameters an outline has been worked out for degree of respiratory failure. The criteria obtained are statistically significant; being able of giving quantitative assessment of degree of respiratory failure they can serve as control figures to be used in evaluations designed to study time course of changes in respiratory failure.  相似文献   
28.
OBJECTIVE: The aim of the study was to compare the clinical effects and hemostatic efficiency of transfusions of platelets preserved in the frozen state for as long as 2 years with transfusions of platelets preserved in the conventional manner for as long as 5 days in patients undergoing cardiopulmonary bypass. METHODS: Seventy-three patients were prospectively randomly assigned to receive transfusions of cryopreserved or liquid-preserved platelets. Nonsurgical blood loss was measured during and after the operation. Bleeding time, hematologic variables, and the bleeding time site shed blood were assayed before cardiopulmonary bypass and at 30 minutes and 2, 4, and 24 hours after transfusion. In vitro platelet function tests were conducted on platelets obtained from healthy volunteers. RESULTS: No adverse sequelae of the transfusions were observed. Blood loss and the need for postoperative blood product transfusions were lower in the group receiving cryopreserved platelets. Lower posttransfusion platelet increments and a tendency toward decreased platelet survival were observed in patients receiving cryopreserved platelets. Hematocrit and plasma fibrinogen were significantly higher in this group, and the duration of intubation was shorter. In vitro, cryopreserved platelets demonstrated less aggregation, lower pH, and decreased response to hypotonic stress but generated more procoagulant activity and thromboxane. CONCLUSIONS: (1) Cryopreserved platelet transfusions are superior to liquid-preserved platelets in reducing blood loss and the need for blood product transfusions after cardiopulmonary bypass. (2) The reduction in blood loss in the patients receiving cryopreserved platelet transfusions after cardiopulmonary bypass probably reflects improved in vivo hemostatic function of cryopreserved platelets. (3) Some in vitro measures of platelet quality (aggregation, pH, hypotonic stress) may not reflect in vivo quality of platelet transfusions after cardiopulmonary bypass, whereas other in vitro measures (platelet procoagulant activity and thromboxane) do.  相似文献   
29.
Perforation, a severe complication of necrotizing enterocolitis (NEC), has a high mortality rate. Recently, we presented a new technique for evaluation of NEC: measuring the CT attenuation coefficient of urine after oral administration of iohexol. We present three cases of neonates with NEC who demonstrated serial increases in urine CT attenuation coefficients, all of whom subsequently deteriorated clinically and radiographically. Surgery in all three cases confirmed severe necrosis and/or perforation. These three cases suggest that the CT attenuation coefficient of urine after oral administration of iohexol may be a more sensitive indicator of NEC severity, progression, and perforation than clinical evaluation and radiography. More investigation is necessary, but eventually, this noninvasive technique may be able to decrease morbidity and mortality by predicting the need for surgical intervention or more aggressive medical management of NEC before perforation occurs.  相似文献   
30.
INTRODUCTION: Recent reports have suggested that breast ultrasound (US) is of value in distinguishing malignant from benign processes. The aim of this study was to establish the accuracy of US in detecting invasive malignancy in clinically benign, discrete, symptomatic breast lumps. METHODS: The US appearances of 205 clinically benign breast masses were documented prospectively and prior to mammography by one radiologist (AJE). The US appearances were then correlated with the fine needle aspiration (FNA), core biopsy and surgical findings and compared with the mammographic findings. RESULTS: The US findings were normal 72 (35%), simple cyst 63 (31%), solid benign 51 (25%), solid indeterminate 15 (7%) and solid malignant four (2%). Ultrasound characterized 13 (93%) of the 14 patients found to have invasive carcinoma as indeterminate or malignant. No patients with normal or simple cyst US findings had invasive malignancy. Ultrasound had significantly better accuracy (97% vs 87%, P < 0.02) sensitivity (93% vs 57%, P < 0.05) and negative predictive value (99% vs 92%, P < 0.002) than mammography in the detection of invasive carcinoma when indeterminate and malignant imaging findings were taken as positive. CONCLUSION: US is a useful adjunct to FNA/core biopsy in confirming the nature of symptomatic, clinically benign breast masses and is superior to mammography in this clinical setting.  相似文献   
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