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61.
A 79-year-old female presented with cavernous sinus hemangioma manifesting as double vision due to right oculomotor and trochlear nerve pareses. Computed tomography and magnetic resonance imaging revealed bony erosion and a right cavernous sinus tumor with "tail sign" after contrast medium administration. Thallium-201 (201Tl) single photon emission computed tomography (SPECT) showed low uptake within the tumor, and technetium-99m-human serum albumin-diethylenetriaminepenta-acetic acid SPECT disclosed high uptake within the tumor. 201Tl SPECT usually shows very high uptake in meningiomas and malignant tumors, so the tumor was considered to be an unrelated benign tumor. The patient underwent partial resection of the tumor. Histological examination of the specimen confirmed cavernous hemangioma. The oculomotor nerve paresis partially improved. Gamma knife radiosurgery was carried out 4 months after the operation. The tumor markedly shrank with full recovery of extraocular movement 6 months after radiosurgery. SPECT is useful for distinguishing cavernous sinus hemangiomas from other cavernous tumors. Radiosurgery should be performed after partial resection or biopsy for cavernous sinus hemangiomas and may be the initial treatment for patients with small cavernous sinus hemangioma if the diagnosis can be established based on neuroimaging.  相似文献   
62.
Abstract: We made an artificial skin comprised of a stratified layer of keratinocytes and a dermal matrix with a type I collagen containing fibroblasts. In this work, we showed keratinocyte behavior under primary culture, gel contractions varying with concentration of collagen solution, and cell growth plots in the collagen gel. The optimum behavior of dermal equivalent could be obtained using 3.0 mg/ml collagen solution and attached gel culture. The attached gel culture had a jumping effect of growth factor on cell growth at the lag phase. To develop the artificial skin, 1× 105 cells/cm2 of keratinocytes were cultured on the dermal equivalent at air-liquid interface. Finally, to overcome the problem that artificial skin of collagen gel was torn easily during suturing of grafting, we prepared histocompatible collagen mesh and attached the mesh to the bottom of the gel. Cultured artificial skins were successfully grafted onto rats.  相似文献   
63.

Objective

To compare the clinical utility of the different imaging techniques used for the evaluation of tracheobronchial diseases.

Materials and Methods

Forty-one patients with tracheobronchial diseases [tuberculosis (n = 18), bronchogenic carcinoma (n = 10), congenital abnormality (n = 3), post-operative stenosis (n = 2), and others (n = 8)] underwent chest radiography and spiral CT. Two sets of scan data were obtained: one from routine thick-section axial images and the other from thin-section axial images. Multiplanar reconstruction (MPR) and shaded surface display (SSD) images were obtained from thin-section data. Applying a 5-point scale, two observers compared chest radiography, routine CT, thin-section spiral CT, MPR and SSD imaging with regard to the detection, localization, extent, and characterization of a lesion, information on its relationship with adjacent structures, and overall information.

Results

SSD images were the most informative with regard to the detection (3.95±0.31), localization (3.95±0.22) and extent of a lesion (3.85±0.42), and overall information (3.83±0.44), while thin-section spiral CT scans provided most information regarding its relationship with adjacent structures (3.56±0.50) and characterization of the lesion (3.51±0.61).

Conclusion

SSD images and thin-section spiral CT scans can provide valuable information for the evaluation of tracheobronchial disease.  相似文献   
64.
This human study was conducted to evaluate the effect of chronic alcohol consumption on plasma concentrations of lipid and the antioxidative system in 44 Korean alcoholics and 45 age-, sex-, and nationality-matched nonalcoholic subjects. Plasma triacylglycerols and atherogenic index were higher in alcoholics than in control subjects. Plasma total cholesterol was not different among groups, but plasma high-density lipoprotein cholesterol was lower in alcoholics. There were positive correlations between ethanol consumption and plasma lipid peroxide and atherogenic index in all subjects; there were negative correlations between ethanol consumption and plasma high-density lipoprotein cholesterol in all subjects. There were no significant differences between alcoholics and control subjects in plasma concentrations of α-tocopherol, although plasma α-tocopherol/lipid tended to be lower in alcoholics. Plasma retinol was lower in alcoholics. These results suggest that chronic ethanol consumption can contribute to increased risk for vascular diseases in Korean alcoholics.  相似文献   
65.
Sevoflurane and isoflurane reduce oxygen saturation in infants   总被引:1,自引:0,他引:1       下载免费PDF全文
Volatile anesthetics are generally known to exert several influences on the respiratory system, but their direct effect on oxygen saturation as measured by pulse oximetry (SpO2) in infants remains unknown. In this study, 70 infants under 2 years of age who received general anesthesia were examined to determine the effects of several volatile anesthetics and nitrous oxide on SpO2. After endotracheal intubation, the subjects were ventilated using a Jackson-Rees circuit with oxygen, nitrous oxide, and either sevoflurane, enflurane, or isoflurane adjusted to twice the adult minimum alveolar concentration (MAC) for the agents when used in combination with 67% nitrous oxide. In all cases, the end-tidal carbon dioxide tension (PetCO2) was maintained within the same range (28-35 mm Hg). Significantly lower SpO2 values (paired t test, P < .05) were observed when the subjects were ventilated with oxygen, 67% nitrous oxide, and sevoflurane or isoflurane--but not with oxygen, 67% nitrous oxide, and enflurane--than when they were administered oxygen, 50% nitrous oxide, and the original concentration of each volatile anesthetic. These results suggest that sevoflurane and isoflurane have different effects from enflurane on gas exchange systems.  相似文献   
66.
OBJECTIVE. We compared the soft-copy images produced by a digital chest radiography system that uses a flat-panel X-ray detector based on amorphous selenium with images produced by a storage phosphor radiography system for the visualization of anatomic regions of the chest. MATERIALS AND METHODS. Two chest radiologists and two residents analyzed 46 pairs of posteroanterior chest radiographs on high-resolution video monitors (2560 x 2048 x 8 bits). In each pair, one radiograph was obtained with a storage phosphor radiography system, and the other radiograph was obtained with a selenium-based flat-panel detector radiography system. Each pair of radiographs was obtained at the same exposure settings. The interpreter rated the visibility and radiographic quality of 11 different anatomic regions. Each pair of images was ranked on a five-point scale (1 = prefer image A, 3 = no preference, 5 = prefer image B) for preference of technique. Statistical significance of preference was determined using the Wilcoxon's signed rank test. RESULTS. The interpreters had a statistically significant preference for the selenium-based radiography system in six (unobscured lung, hilum, rib, minor fissure, heart border, and overall appearance) of 11 anatomic regions (p<0.001) and for the storage phosphor system in two regions (proximal airway and thoracic spine) (p<0.05). Chest radiologists strongly preferred selenium-based images in eight regions, and they did not prefer storage phosphor images in any region. CONCLUSION. The soft-copy images produced by the selenium-based radiography system were perceived as equal or superior to those produced by the storage phosphor system in most but not all anatomic regions.  相似文献   
67.
The "High-Riding" superior pericardial recess: CT findings   总被引:3,自引:0,他引:3  
OBJECTIVE. We recently observed patients in whom the superior pericardial recess extended cephalad ("high-riding") into the right paratracheal region. In these patients, differentiation from mediastinal lymphadenopathy or mass was difficult. The purpose of this study was to assess the prevalence and CT features of the high-riding superior pericardial recess. CONCLUSION. Narrow-collimation CT with multiplanar reformations was useful for confidently diagnosing a high-riding superior pericardial recess and for distinguishing it from pathologic lesions.  相似文献   
68.
Renal and pulmonary lymphangioleiomyomatosis: a case report   总被引:1,自引:0,他引:1  
Lymphangioleiomyomatosis (LAM) is a rare disease that most commonly involves the lung. However, extrapulmonary lymphangioleiomyomatosis rarely occurs with or without subsequent involvement of the lung. We report a case of incidentally found renal and pulmonary lymphangioleiomyomatosis in a patient who had no stigmata of tuberous sclerosis.  相似文献   
69.
70.
In surgical treatment of aortic arch aneurysm or aortic dissection, we have been employing retrograde cerebral perfusion (RCP). In the present study, we have developed "arch vessels first technique" to shorten perfusion time and achieved an excellent clinical outcome. The surgical procedure "arch vessels first technique" is outlined as follows. RCP is initiated following circulatory arrest, while a woven dacron graft (12 mm in diameter, the dacron graft must be prepared in advance) with two side arms (12 mm in diameter, i.e., with the same diameter) is anastomosed left subclavian artery, left common carotid artery and right brachiocepharic artery in a sequential manner. Then, brain circulation is initiated via one end of the dacron graft. Subsequently, in patients with aortic dissection, a 26 mm woven dacron tubular prosthesis is inserted, using an elephant trunk procedure, to perform "distal anastomose". A partial clamp is applied to the 12 mm woven dacron graft mentioned above, while this 26 mm graft is anastmosed to the 12 mm woven dacron graft side to side, thus reinitiating systemic circulation. While rewarming, the 26 mm woven dacron tubular prosthesis is proximal anastomosed. Mean RCP time was 79.4 minutes, using the conventional procedure "aortic arch distal anastomose", whereas the RCP time was shortened by this procedure "arch vessels first technique", as evidenced by mean RCP time of 57 minutes for patient with aortic dissection and of 39 minutes for patient with saccular aneurysm.  相似文献   
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