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991.
Adamantinoma, a rare bone lesion of the tibia and fibula, has two distinct variants, classic adamantinoma and osteofibrous dysplasia-like adamantinoma. Composite lesions have not been described. Aneurysmal bone cyst is a benign cystic lesion which may also occur in the tibia and fibula. We report an unusual case of classic adamantinoma with osteofibrous dysplasia-like areas and foci of secondary aneurysmal bone cyst with prominent giant cells. A lesion was diagnosed in a 17-year-old girl with a 14-year history of a slowly enlarging left tibial mass and increasing deformity. Pathologically, the predominant pattern was classic adamantinoma, with minor foci of osteofibrous dysplasia-like adamantinoma and areas of secondary aneurysmal bone cyst with abundant multinucleated giant cells. We report the clinical, radiologic, and pathologic features of this case, and summarize lesions associated with secondary aneurysmal bone cyst. To our knowledge, the association of adamantinoma with secondary aneurysmal bone cyst has not been previously reported.  相似文献   
992.
We report a hepatic tumor in an adolescent that does not fit into any of the described categories of liver tumors. The patient presented with hepatomegaly, abdominal pain, and normal liver function test; the tumor was cystic in imaging studies. The resected specimen, result of a partial hepatectomy, measured 21 cm and was multicystic with solid areas. Microscopically, the cysts were lined by a mucous-producing or intestinal-type epithelium, associated with smooth muscle and small mucous-producing glands. The solid component contained fibrous and adipose tissue, smooth muscle and thick-walled vessels. Aneuploidy was demonstrated by flow cytometry. We interpreted the tumor as having features of a mesenchymal hamartoma and congenital solitary nonparasitic cyst. It is conceivable that the lesions originated with small peribiliary glands with dilatation and intestinal metaplasia.  相似文献   
993.
Foreign bodies in a mobile tongue are rarely presented to the laryngologist, because such bodies are commonly lodged superficially and are easily removed by the patients themselves or by general practitioners. Thus, it is rare that a foreign body totally embedded in the mobile part of the tongue presents as an enlarged tongue mass. We have described a 64-year-old female with a 3-month history of an enlarged mass in the anterior right tongue. Physical examination showed a mass located in the anterior right tongue, with intact mucosa and normal color. A benign tongue neoplasm was considered first. However, a fish bone totally embedded in the mobile tongue with granuloma formation was encountered during the incisional biopsy operation. Complete removal of the foreign body with granuloma was achieved under local anesthesia. There was no neuromuscular or neurosensory deficit of the tongue in the follow-up period of 2 years. Although an embedded foreign body in the mobile tongue is a rare condition, it should be considered in the work-up of a patient with an enlarged tongue mass, with or without a history of swallowing a foreign body.  相似文献   
994.
The objectives of this study were to establish whether there is an obvious difference between intact mucosa and abraded mucosa of the middle-ear cavity in respect to the potential side effects from the application of absorbable gelatine sponge (Gelfoam) and to investigate if Gelfoam combined with corticosteroid ointment (cortimycine, sterile 1% hydrocortisone acetate) can reduce the occurrence of these effects. Twenty Albino rats were used in the study. These animals were divided into four groups, with ten ears in each group. In group A, the middle-ear mucosa was kept intact, and Gelfoam was inserted into the middle-ear cavity. In group B, the middle-ear mucosa was abraded, and Gelfoam was inserted. In group C, Gelfoam with corticosteroid was implanted over the intact mucosa, and in group D, the mucosa was abraded prior to the insertion of Gelfoam with corticosteroid. The changes were evaluated 8 weeks postoperatively. In group A, there was a minimal increase in fibroblastic activity, vascular proliferation with mild to moderate fibrosis and all but two tympanic membranes were perfectly normal. However, in group B, we encountered a significant increase in fibroblastic activity, vascular proliferation and fibrosis, and we observed that all tympanic membranes were moderately to severely thickened. These histopathologic changes related to Gelfoam were noted to be decreased in group C and especially in group D. As previously reported in the literature, Gelfoam was found to promote the formation of connective tissue in the middle-ear cavity regardless of the status of the mucosa. The unwanted effects of this material may be decreased if it is combined with corticosteroids in the middle-ear cavity.  相似文献   
995.
We subjectively and objectively evaluated 136 patients with socially unacceptable snoring (SUS) or obstructive sleep apnoea syndrome (OSAS) treated with uvulopalatopharyngoplasty (UPPP) after a diagnostic workup by sleep registration (polysomnography, PSG) and sleep endoscopy. Of the 136 patients, there were 88 with OSAS and 48 with SUS. The results of the procedure were considered subjectively to be an improvement in 38 (79%) of the SUS patients and in 74 (84%) of the patients with OSAS. In 36 (40%) of the 88 patients with OSAS, repeating PSG postoperatively was considered unnecessary because of obvious improvement. Of the 52 patients with a measurement after UPPP, a decrease in the apnoea hypopnoea index (AHI) was found in 38 (73%; median decrease: 48%), and AHI dropped below 20 in 32 (62%). The apnoea index (AI) was available in 49 (56%) patients and was reduced in 31 (63%; median decrease: 73%). An overall positive result in the 88 patients with OSAS (combining available data on subjective and objective results) was therefore found in 61 (69%; positive subjective result and AHI <15) or 71 (81%; positive subjective result and decrease in AHI), respectively, depending on the definition. We conclude that after diagnostic workup by sleep registration and sleep endoscopy, the success rate of UPPP increases as compared to historical controls.  相似文献   
996.
This study was designed to determine which objective acoustic or aerodynamic parameters allowed a homogeneous group of patients with unilateral vocal fold paralysis (UVFP) to be distinguished from an age-matched and smoking-matched control group and to search for linear correlations between the objective parameters and the subjective breathiness ratings. Eight patients with recent-onset UVFP and 12 controls were prospectively studied. The acoustic parameters measured for the vowel /a/ at a comfortable frequency and intensity were: jitter, shimmer, harmonics-to-noise ratio, cepstral peak prominence, the difference between the levels of the first two harmonics and the relative energy above 6 kHz. Aerodynamic parameters included the mean flow rate during a sustained /a/ and intraoral pressure during the production of the phoneme /pi/. The long-term average spectrum was calculated for 40 s of text, and the relative average energies in four frequency bands were compared. Six judges rated a mid-/a/ sample using a five-parameter scale with four levels of severity. Nonparametric statistical analysis revealed significant differences ( P<.05) between the UVFP group and the control group for 14 of the 19 parameters studied. Correlations between the objective parameters and perceived breathiness differed in the two groups. Correlations were not always as expected as based on previous literature reports. These measurements provided an objective qualification of voice in patients with UVFP and successfully distinguished them from the normal controls. The objective acoustic and aerodynamic measurements had generally low linear correlations with breathiness ratings in the control group. Higher correlations were seen in the UVFP group, in which breathiness was best correlated with airflow measurements.  相似文献   
997.
998.
During a surgery of basilar aneurysms via the trans-sylvian approach, we encountered an arterial bleeding caused by rupture of an internal carotid artery aneurysm that had been difficult to diagnose before surgery, as it was a small and brood-neck aneurysm and mimicked arteriosclerosis. In spite of several surgical procedures, the surgical path at the basilar aneurysms became narrow, and we had to abandon the clipping of the aneurysms. Consideration of radiological and intraoperative findings was made for this case, demonstrating a pitfall that neurosurgeons may encounter during surgery. Received: 16 December 1998 / Accepted: 26 May 1999  相似文献   
999.
Trichloroethylene (TCE), a volatile liquid used as a degreasing agent, is a common environmental pollutant. In 2001, the EPA published a draft risk assessment for TCE that incorporates dosimetry predictions of physiologically based pharmacokinetic (PBPK) models. The current modeling effort represents an expansion and extensive tissue dosimetry validation of rodent PBPK models for TCE. The pharmacokinetics of TCE in male Sprague-Dawley (S-D) rats were characterized (1) during and after inhalation exposure to 50 or 500 ppm TCE, (2) following administration of 8 mg/kg TCE PO, and (3) following intra-arterial injection of 8 mg/kg TCE. Blood and tissues (including liver, kidney, fat, skeletal muscle, heart, spleen, gastrointestinal tract, and brain) were collected at selected time-points from 5 min up to 24 h post initial exposure. The fat compartment was modified to be diffusion-limited to predict the observed slow release of TCE from the fat. The addition of a deep liver compartment was necessary to accurately predict the slower hepatic clearance of TCE for all three exposure routes. Simulations of liver concentrations following gavage of male B6C3F1 mice with 300-2000 mg/kg TCE were also improved with the addition of a deep liver compartment. Liver predictions were calibrated and validated using a cross-validation technique novel to PBPK modeling. Splitting of compartments did not significantly affect predictions of TCE concentrations in the liver, fat, or venous blood. This model expansion and validation increases both the utility and our confidence in the current use of rodent TCE PBPK models in human health risk assessment.  相似文献   
1000.
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