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101.
L Bernà A Chico X Matías-Guiu E Mato A Catafau C Alonso J Mora D Mauricio J Rodríguez-Espinosa C Marí A Flotats JC Martín M Estorch I Carrió 《Canadian Metallurgical Quarterly》1998,25(11):1482-1488
Detection of recurrence of medullary thyroid carcinoma (MTC) remains a diagnostic problem. Increased serum tumour marker levels frequently indicate recurrence while conventional imaging techniques (CIT) are non-diagnostic. In this study, we performed indium-111 octreotide scintigraphy and CIT in a series of 20 patients with MTC presenting with elevated serum tumour markers after surgery. 111In-octreotide whole-body studies detected 15 pathological uptake foci in 11 of the 20 patients studied and CIT detected 17 lesions in 11 of the 20 patients. Ten patients underwent reoperation, five of them with positive 111In-octreotide scintigraphy and CIT and two with positive isotopic exploration and negative CIT. Surgical findings demonstrated that the results of isotopic study and CIT had been false-positive for MTC in one case (sarcoidosis). The six patients with true-positive 111In-octreotide studies had significantly higher basal calcitonin (CT) and carcinoembryonic antigen (CEA) levels than the patients with negative isotopic studies. The expression of somatostatin receptor (SSTR) subtypes by PC-PCR could be investigated in four cases with a positive isotopic study. Among the three cases with a true-positive study, SSTR2, the SSTR subtype that preferentially binds to the somatostatin analogue octreotide, was detected in two, SSTR5 was demonstrated in the three, and SSTR3 was detected in one. No subtype of SSTR was detected in the case with a final diagnosis of sarcoidosis. We conclude that 111In-octreotide has limited sensitivity in detecting recurrence in patients with MTC, although its sensitivity may improve with high serum CT levels. This radionuclide imaging technique should be employed when conventional imaging techniques are negative or inconclusive or when the presence of somatostatin receptors may provide the basis for treatment with somatostatin analogues. 相似文献
102.
A del Río JJ Vázquez JA Sobrino A Gil J Barbado I Maté J Ortiz-Vázquez 《Canadian Metallurgical Quarterly》1978,74(4):414-417
A relatively high incidence of heart failure is noted among patients with systemic lupus erythematosus (SLE) without clearly defined clinical causes. To evaluate left ventricular performance in patients with SLE without evidence of cardiovascular disease, noninvasive measurement of the systolic time intervals was carried out. Simultaneous recording of the electrocardiogram, phonocardiogram and carotid arterial pulsation were obtained in 25 patients with systemic lupus erythematosus and compared with 22 normal subjects. The patients with SLE had a shorter left ventricular ejection time (P less than 0.05), a longer pre-ejection period (P less than 0.02) and an increased ratio of pre-ejection period/left ventricular ejection time (P less than 0.005). These abnormalities on ventricular function were independent of age, duration of the disease, hypertension, renal involvement, anemia, immunologic activity and corticosteroid treatment. Several etiologic possibilities are discussed and the clinical usefulness of this method to detect and follow-up the cardiac dysfunction in systemic lupus erythematosus is emphasized. 相似文献
103.
Hariyadi Soetedjo O. Mohd Nizam Idris Sabtu J. Mohd Sazli Ashaari Yusof Y. Mohd Razman A.F. Awang Mat 《Microelectronics Journal》2006,37(6):480-482
Various pseudomorphic High Electron Mobility Transistor (pHEMT) structures of AlGaAs/InGaAs alloys have been observed their current-voltage behavior. The tungsten probes were used for a measurement the structures by ramping the voltage from −5 to 5 V and measure the electrical current. Measurement was carried out at room temperature and also under optical illumination. From the measurement, the electrical current was found to increase as the increase of Al content in the AlGaAs alloys layer in the pHEMT structure. This phenomenon was supported by the decrease of sheet resistance as obtained from Hall effect measurement. Under visible light illumination, the current-voltage behavior of pHEMT structure was observed to vary as the light power density was varied for 0, 25 and 55 μW/cm. 相似文献
104.
105.
Sayed Amir Hossein Goli Miskandar Mat Sahri Mahdi Kadivar 《European Journal of Lipid Science and Technology》2008,110(12):1102-1108
Structured lipids containing conjugated linoleic acid as a functional ingredient were blended with palm stearin in the ratios of 30 : 70, 40 : 60, 50 : 50, 60 : 40 and 70 : 30 (wt/wt). The blends were subjected to enzymatic interesterification by Candida antarctica lipase. After interesterification of the blends, changes in the physical properties of the products, including lower melting points and solid fat contents along with different melting behaviors, were evidenced. Analysis of triacylglycerols (TAG) of the interesterified blends showed a decrease in the concentration of high‐melting TAG. X‐ray diffraction analysis revealed, that all the reacted blends were predominantly in the β' crystal form. The mixture could be used for the formulation of margarines or other, similar products. 相似文献
106.
Fluoroscopy-based 3-D reconstruction of femoral bone cement: a new approach for revision total hip replacement 总被引:1,自引:0,他引:1
de la Fuente M Ohnsorge JA Schkommodau E Jetzki S Wirtz DC Radermacher K 《IEEE transactions on bio-medical engineering》2005,52(4):664-675
In revision total hip replacement the removal of the distal femoral bone cement can be a time consuming and risky operation due to the difficulty in determining the three-dimensional (3-D) boundary of the cement. We present a new approach to reconstruct the bone cement volume by using just a small number of calibrated multiplanar X-ray images. The modular system design allows the surgeon to react intraoperatively to problems arising during the individual situation. When encountering problems during conventional cement removal, the system can be used on demand to acquire a few calibrated X-ray images. After a semi-automatic segmentation and 3-D reconstruction of the cement with a deformable model, the system guides the surgeon through a free-hand navigated or robot-assisted cement removal. The experimental evaluation using plastic test implants cemented into anatomic specimen of human femoral bone has shown the potential of this method with a maximal error of 1.2 mm (0.5 mm RMS) for the distal cement based on just 4-5 multiplanar X-ray images. A first test of the complete system, comparing the 3-D-reconstruction with a computed tompgraphy data set, confirmed these results with a mean error about 1 mm. 相似文献
107.
Biotechnology-derived food crops are currently being developed in Malaysia mainly for disease resistance and improved post harvest quality. The modern biotechnology approach is adopted because of its potential to overcome constraints faced by conventional breeding techniques. Research on the development of biotechnology-derived papaya, pineapple, chili, passion fruit, and citrus is currently under way. Biotechnology-derived papaya developed for resistance to papaya ringspot virus (PRSV) and improved postharvest qualities is at the field evaluation stage. Pineapple developed for resistance to fruit black heart disorder is also being evaluated for proof-of-concept. Other biotechnology-derived food crops are at early stages of gene cloning and transformation. Activities and products involving biotechnology-derived crops will be fully regulated in the near future under the Malaysian Biosafety Law. At present they are governed only by guidelines formulated by the Genetic Modification Advisory Committee (GMAC), Malaysia. Commercialization of biotechnology-derived crops involves steps that require GMAC approval for all field evaluations and food-safety assessments before the products are placed on the market. Public acceptance of the biotechnology product is another important factor for successful commercialization. Understanding of biotechnology is generally low among Malaysians, which may lead to low acceptance of biotechnology-derived products. Initiatives are being taken by local organizations to improve public awareness and acceptance of biotechnology. Future research on plant biotechnology will focus on the development of nutritionally enhanced biotechnology-derived food crops that can provide more benefits to consumers. 相似文献
108.
依据室温下双电层的研究方法,探讨了在高温,高矿化度的油藏条件下平面扩散双电层的基本特性。以NaCl为主要电解质的地层水为例,在温度为20-200℃,矿化度为1000-100000mG/L的条件下,分别计算了双电层的厚度,电势分布,离子浓度分布和电荷密度分布。 相似文献
109.
从分形理论和统计物理学的角度介绍了地震道分维和熵的计算方法,并利用实际地震资料进行了计算.结果表明:地震道含油气和不含油气时的关联维与熵有明显的差异;地震道的关联维和熵有很好的相关性;熵的计算比较简单。在根据地震资料作油气检测时用熵作为含油气指标之一比用关联维更合适. 相似文献
110.
Summary The base catalyzed reaction between epoxide and carboxyl groups was studied using a simple model system phenylglycidyl ether-caproic acid in the presence of triethylamine. The reaction was investigated by mass spectrometry and GPC which provide an overall qualitative and quantitative survey of all the forming reaction products. The addition esterification is followed by etherification and condensation esterification and the main reaction product, monoester, is disproportionated yielding diester and diol. In a polyfunctional system, the latter reaction may cause splitting of the polymer chain and formation of new crosslinks. 相似文献