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M Cappello PW Bergum GP Vlasuk BA Furmidge DI Pritchard S Aksoy 《Canadian Metallurgical Quarterly》1996,54(5):475-480
A case of cranial hypertrophic pachymeningitis of unknown etiology in a patient with 15-year history of headaches, cranial nerve palsies, and gait disturbance is reported. A 77-year-old woman was brought to our institute in a coma. CT revealed intracerebral hemorrhage in the right temporal lobe and thickening of the falx and tentorium. Fifteen years previously the patient had undergone CT scanning because of headaches, cranial nerve palsies, and progressive gait disturbance and a thickened tentorium, mild hydrocephalus and edematous change in the right temporal lobe had been reported. Since the etiology of her symptoms was unclear at the time, she did not receive adequate treatment. Her symptoms gradually progressed thereafter, and her visual acuity and hearing deteriorated. MR imaging in 1994 showed the thickened tentorium as a hypointense area with hyperintense edges on Gd-DTPA enhanced images. Angiography revealed narrowing of posterior portion of the superior sagittal sinus. The patient's condition rapidly deteriorated due to the intracranial hypertension and she subsequently died. Autopsy revealed a thickened tentorium with xanthochromic surface. This hypertrophic change was also seen in the dura mater of the posterior and middle cranial fossa. Microscopic examination of the thickened tentorium revealed extensive fibrous tissue with a chronic inflammatory infiltrate, predominantly of lymphocytes. No specific lesions were revealed by staining with hematoxylin-eosin, PAS, Gram's or Ziehl-Neelsen stains. The patient had no inflammatory or infectious diseases of other organs, and a diagnosis of idiopathic cranial hypertrophic pachymeningitis of unknown etiology was made. Considering the above findings, the thickened tentorium depicted as a hypointense area on the T1- and T2-weighted images and the Gd-enhanced edges of the tentorium are thought to be represent fibrous tissue and inflammatory regions, respectively. 相似文献
74.
Characteristics of safflower seed oils of turkish origin 总被引:1,自引:1,他引:0
A. Işigigür F. Karaosmanoglu H. A. Aksoy 《Journal of the American Oil Chemists' Society》1995,72(10):1223-1225
Technological characteristics of oils extracted from seventeen varieties of safflower seeds (Carthamus tinctorius L.) of Turkish origin were investigated for their utilization prospects in the food industry and in other industrial sectors.
Standard procedures were applied to determine the technological characteristics of seventeen varieties of safflower seeds
and the safflower seed oils; fatty acid compositions were determined by gas-liquid chromatography. Results show that safflower
seed oils are suitable both for food and industrial purposes. 相似文献
75.
The aim of this work was to improve mechanical properties such as flexural strength and interlaminar shear strength (ILSS) of polyetheretherketone (PEEK) thermoplastic polymer which has very high processing temperature due to its high melting temperature. Carbon fiber (CF) surface was modified by two different methods: oxidative and non-oxidative. Piranha solution and chromate solution were used for chemical treatment (oxidative treatment), and silicone based polymers were used for polymer coating (non-oxidative). The changes on the surface structure and surface chemistry were characterized by scanning electron microscopy and Fourier transform infrared spectroscopy (FTIR), respectively. FTIR results indicate that coating fibers decreases carbon element content, whereas increases the oxygen and silicone content as well as their functional groups on the surface. Flexural strength and ILSS properties of CF/PEEK composites were measured according to ASTM D-790 and ASTM D2344, respectively. 相似文献
76.
Capsella bursa-pastoris (L.) Medic. (shepherd's purse) has been tested as a possible biomonitor of heavy metals in the city of Bradford, UK and compared with Poa annua L. (annual meadow-grass), a species with a similar ecology that had previously been studied for biomonitoring potential. Forty-two sites (urban roadside, urban, urban park, suburban and rural) in and around Bradford were investigated. Concentrations of Pb, Cd, Zn and Cu have been determined in soils and in washed and unwashed plant leaves. Differences between the washed and unwashed samples, reflecting airborne and soil entry routes, respectively, varied according to the metal pollutant. There were significant relationships between the heavy metal concentration in samples of surface soil (depth 0-10 cm) and washed leaves, the concentrations being greater with progressively increased urbanisation of the sites. Capsella bursa-pastoris has been found to be a useful biomonitor of the four heavy metals studied, and it may be a particularly useful species since it could monitor short-term changes in pollution in urban areas. 相似文献
77.
Estimating the magnitude of profile scale factor is currently based on the assumption that beach profiles are in equilibrium condition. However, this assumption cannot be applied to all beach profiles. In this article, a boundary based profile scale factor is proposed that through a normalized coordinate system leads to a unique global profile scale factor. The global profile scale factor helps to determine an initial linear beach profile. The amount of erosion and accretion that causes the initial linear profile to transform to the natural equilibrium beach profile (EBP) can be calculated. Accordingly, the balance between the amount of erosion and accretion will identify a turning point distinguishing the erosion and accretion areas on the profile. This turning point helps to evaluate whether the profile is in equilibrium condition or not. The proposed model was validated through various beach profiles resulting in high degrees of accuracy and reliability. 相似文献
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79.
The results of surveillance for ochratoxin A (OTA) in 1885 samples of sultanas taken during five crop years between 1999 and 2003 are reported. The analytical method was based on extraction with methanol + sodium bicarbonate and clean-up by immunoaffinity column chromatography followed by high-performance liquid chromatography with fluorescence detection. The limit of detection for OTA was 0.3 µg kg-1. The results show that 9.3% of the samples contained no detectable levels of OTA, whereas 0.6% had concentrations exceeding 10 µg kg-1; the remaining 90.3% had levels within the range 0.3-10 µg kg-1. The overall mean OTA concentration in the total number of 1885 samples taken was 1.36 ± 2.91 µg kg-1; the overall median was calculated as 0.90 µg kg-1. 相似文献
80.
Networks and Spatial Economics - This paper introduces a modified version of the Hansen-gravity model as a framework to estimate the accessibility of higher education (HE) institutions in Italy... 相似文献