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2.
Bifid mandibular canal.   总被引:1,自引:0,他引:1  
PURPOSE: To determine the incidence and characteristics of bifid mandibular canals. METHODS: A retrospective study was performed using panoramic radiographs of 2012 patients subjected to dental treatment in the Dental Clinic of the Valencia University Dental School (Valencia, Spain) between 1996 and 1999. The goal was to investigate the presence of double mandibular canals. RESULTS: The extraoral panoramic radiographs revealed a total of 7 images suggestive of bifid canals. Mandibular computed tomography revealed the existence of this anatomic variant in 2 of 3 patients. An analysis was performed on the incidence of this type of image in extraoral panoramic radiography, its possible interpretations, and the clinical implications of bifid mandibular canals. CONCLUSIONS: In this study, 0.35% of canals were bifid. All cases were in women.  相似文献   
3.
The purpose of this study was to analyze the clinical aspects in 130 patients presenting periodic lateralized epileptiform discharges (PLEDs) in their EEG and to compare these results with those found in the literature. Etiology, neurologic deficit, seizure occurrence, and evolution were studied in each patient by historical review. The recordings were obtained on 8- or 16-channel EEGs with electrode placement according to the International 10-20 System. Recordings containing PLEDs were selected. PLEDs were defined as repetitive periodic, focal, or hemispheric epileptiform discharges (spikes, spike and waves, polyspikes, sharp waves) usually recurring every 1 to 2 seconds. The statistical study was carried out via the chi(2) test using the computer program SPSS. The main etiology found in this group of patients was stroke (61 of 130 patients). Other processes found were brain infections, tumors, hematomas, and several other entities grouped together as miscellaneous (anoxic encephalopathy, subarachnoid hemorrhage, craniocerebral trauma, Creutzfeldt-Jacob disease, migraine, multiple sclerosis, and aminophylline intoxication). Half of these patients (65 of 130) developed seizures, mostly partial motor seizures. No significant relation between etiology and seizures was found (chi(2) = 2.81, P = 0.4222). Seizures recurred in 14 of 130 patients during a follow-up of 14.5 months. PLEDs were not recorded in any EEG at the time of seizure recurrence. PLEDs constitute a distinctive but uncommon EEG phenomenon of repetitive, periodic, and stereotyped lateralized complexes. In agreement with the literature, PLEDs were associated with an acute process and occurred early during the course of the illness in all patients studied and were usually associated with structural lesions, with stroke being the main etiology. Traditionally, seizures occur with PLEDs but it is also accepted that they can exist in patients who never develop epileptic activity, either clinically or electrically, as demonstrated in 50% of the patients studied. No significant association between seizures and any etiology could be found. It was not demonstrated that the occurrence of seizures may influence the outcome in any way.  相似文献   
4.
In the last years, granulocyte and granulocyte-macrophage colony-stimulating factors (G-CSF and GM-CSF) are being increasingly used and several cutaneous eruptions have been reported in relation to these treatments. In 1991 Horn et al. described three patients with maculopapular eruption that paralleled the time of infusion of GM-CSF. Two of the cases showed an increase in the number and size of macrophages in the biopsy specimen. Since then, several cases have been reported showing this histopathological alteration that has been considered characteristic of reaction to G-CSF or GM-CSF. Although maculopapular eruption with enlarged macrophages can appear after chemotherapy treatment, we have found that the presentation of this eruption after the beginning of cytokine treatment is suggestive of the involvement of G-CSF and GM-CSF in the eruption. We described eight cases of patients treated with G-CSF or GM-CSF that developed maculopapular eruptions with enlarged macrophages.  相似文献   
5.
The expression of c-fms oncoprotein in different primary tumours as well as in their metastases in bone marrow, was shown. All the samples were fixed and processed by the acetone, methyl benzoate, xylene procedure (AMeX), which was suitable for studying oncoprotein expression not only in primary tumours but also in bone marrow (BM) biopsies. Among the patients suffering from acute myeloid leukaemia (AMeL), positive c-fms cells were found in 55% cases. On the contrary, patients with lymphocytic cell disorders have not had detectable c-fms oncogene product in BM biopsies.c-fms oncoprotein was also detected in some primary tumour specimens (lung carcinoma, cervical carcinoma, gastric carcinoma, breast carcinoma and melanoma) and their metastases in BM, while it was not present in normal uterine tissue. There was a positive correlation between c-fms oncoprotein expression in primary and metastatic tumours. Our results showed that c-fms product is confined, not only to some normal, but also to the variety of malignant cells of different origin.  相似文献   
6.
Increased fibrinolytic activity is a well recognized constant finding observed during cardiopulmonary bypass (CPB). The purpose of the present work was to study and estimate the factors involved in the plasminogen activation and prekallikrein-kallikrein systems in a population of adult patients undergoing open heart surgery with CPB. Plasminogen activator activity determinations with a fibrinolytic method as well as plasminogen activation and prekallikrein-kallikrein determinations with synthetic substrates were carried out. Our results indicate that no active fibrinolysis but a fibrinolytic potential, similar to that observed in blood obtained after venous occlusion, can be demonstrated in circulating plasma during CPB. This fibrinolytic potential is related to the presence of vascular plasminogen activator released from endothelial cells by the CPB stimulus.  相似文献   
7.
Ocular symptoms in internal carotid artery occlusion]   总被引:1,自引:0,他引:1  
The internal carotid artery occlusion causing an insufficiency of the cerebral circulation manifests itself--besides the neurological symptoms--by disorders of the visual organ. One can distinguish among them early, functional symptoms in the form of transient unilateral hemianopia on the side opposite to the occluded carotid artery and the attacks of transient amblyopia. Signs of fixed ischaemia of the eye ball appear afterwards in the form of oculomotor and pupillary disturbances, neovascularization of the iris, disturbances of the IOP, central retinal artery occlusion, ischaemic optic atrophy. The authors emphasize the value of Doppler's diagnostic ultrasonography, a fast and non-invasive method of direct evaluation of the blood flow in the internal carotid artery system.  相似文献   
8.
BACKGROUND AND PURPOSE: Helical tomotherapy can eliminate the need for junction lines. The goal of this study is to evaluate tomotherapy in the delivery of CSA radiation and measurement of plan quality using physical parameters in comparing conventional (CSA-RT) and helical tomotherapy (CSA-TOMO) plans. PATIENTS AND METHODS: CSA-TOMO and CSA-RT plans were created for dosimetric comparison. Integral dose values were calculated. The ratios D50% (dose received by 50% of the organ at risk's volume) and D10% (dose received by 10% of the organ at risk's volume) were calculated representing large volumes and small volumes of organs at risk receiving significant dose. RESULTS: When considering D50% and D10%, CSA-TOMO has a dosimetric advantage over CSA-RT for most organs at risk. The body integral dose was higher for the CSA-TOMO plan by approximately 6.5%. CONCLUSIONS: Tomotherapy is a feasible alternative for treatment of CSA. Analysis shows that tomotherapy improves dose ratios over conventional radiation for most organs at risk. The impact of a small increase in whole body integral dose is unknown. Long-term follow-up will be needed to answer this question as others have argued of the possibility of increased risk of secondary malignancies due to delivery of radiotherapy with IMRT.  相似文献   
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10.
A nitrogen-specific gas-chromatographic method is described for the quantitative analysis of soluphylline without the need for derivatization or evaporation of solvent, and using only 50 microliters of serum. The analysis is performed isothermally on a silicone stationary phase, 2% SP 2250 DA (Supelco). After a single neutral extraction with ethyl acetate containing the internal standard (beta-hydroxypropyl theophylline), an aliquot of the organic solvent is injected directly into the gas chromatograph. The detector sensitivity (least measurable amount) for soluphylline was 1 ng.  相似文献   
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