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21.
INTRODUCTIONThemaintreatmenttodateforovariancarcinomaissurgicalresection,thesocalledcytoreductivesurgery.Toperformacompleteresection,surgeonsusuallydependonvisualandtactilesensesaswellassurgicalinstinctswhicharerelativelycrudeinidentifyingsubclinicalmicroscopictumor.Radioimmuno--guidedsurgerysystem(RIGS)hasbeentakenoverthelast10yearsinbothlaboratoryandclinicalsettings.However,onlyafewreportswereseenaboutitsstudyinovariancancerworldwideespeciallyinourcountry.OurstudyincludeestablishingaR…  相似文献   
22.
4,7,13,16,21,24-Hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane (Kryptofix® 2.2.2) is used in the routine preparation of [18F]-labeled tracers employed in positron emission tomography (PET) imaging. Confirming the absence of Kryptofix® in radiopharmaceuticals is a quality control criterion required before they can be released for human use. Analysis of Kryptofix® levels using the iodoplatinate spot-test can be complicated by false-positive results due to nitrogen containing tracers and/or false-negative results caused by added stabilizers. To overcome this issue, we have developed a universal TLC method for the rapid and reliable determination of Kryptofix® levels in the wide range of fluorine-18 radiopharmaceuticals we prepare, including complex multi-component formulations.  相似文献   
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Fluorine MR spectroscopy ((19)F MRS) is an indispensable tool for assessing the pharmacokinetics of fluorinated drugs. Since the metabolism of 5-fluorouracil (5FU), a frequently used cytotoxic drug, is expected to be different in normal liver and in tumor tissue, spatial localization is required for detection by MRS. In this study, three independent signal-to-noise ratio (SNR) optimizations were combined to enable chemical shift imaging (CSI) as a localization method in the detection of 5FU and its metabolites in tumor tissue. First, the hardware was optimized by using circularly polarized coils together with integrated preamplifiers. Second, the optimal pulse angle (Ernst angle) was determined on the basis of T(1) relaxation time measurements of 5FU. Finally, averaging of CSI phase-encoding steps was optimized by using the applied Hamming filter as a weighting function. The combination of these three methods enables the in vivo detection of 5FU and alpha-fluoro-beta-alanine (FBAL) by (19)F MRS, localized in three dimensions in tumor and liver tissue at a time resolution of 4 min at 1.5 Tesla.  相似文献   
24.
The modifying potential of two nephrotoxic agents, harman and norharman, on N-ethyl-N-hydroxyethylnitrosamine (EHEN)-induced renal and hepatic carcinogenesis was investigated in male F344/DuCrj rats. Animals were given 0.1% EHEN in their drinking water for the first 2 weeks as an initiator. Subsequently, starting 3 weeks from the commencement, they were fed diet containing these compounds at concentrations of 1000, S00 or 0 ppm until week 26, and then killed for light microscopic examination. The mean numbers of renal tubular cell hyperplasias/cm2 and those of tumors/cm2 in rats given harman and norharman at 1000 ppm after initiation, but not at 500 ppm, were significantly increased as compared to the control values. However, neither compound modified liver carcinogenesis. It is concluded that harman and norharman show enhancing effects on rat kidney carcinogenesis, when ingested at dose levels which cause renal tubular damage.  相似文献   
25.
青年男性MMPI-215F量表应答时间效应分析   总被引:1,自引:1,他引:0  
目的分析青年男性心理测评中F量表条目应答时间,研究其相关影响因素和变化规律,并对该测评计算机化过程中应答时间的设定提供一定的参考.方法使用MMPI-215对全国18个省市的青年男性进行测试,利用计算机对时间记录,汇总分析.结果青年男性在F量表各条目平均应答时间(以下简称F均时)为4.57s;低于总测试的各条目平均应答时间(6.34 s)(P<0.01);F均时与F分数、应答前后不一致的条目数以及漏答条目数有显著相关;F均时受文化程度、年龄、城乡结构多种因素影响;每个条目的应答时间主要取决于条目汉字的个数.结论 F均时在测评中表现出一定的变化规律,可以结合临床进一步深入研究,使其成为评价青年男性性格特征的客观性指标之一.  相似文献   
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27.
IL-17 family members belong to a distinct category of cytokines that coordinate local tissue inflammation by inducing the release of pro-inflammatory and neutrophil-mobilizing cytokines. The importance of the IL-17 family in inflammatory and autoimmune disease is becoming increasingly apparent. IL-17F is a recently discovered member of the IL-17 family that has a number of biological activities through induction of various cytokines, chemokines, and mediators. IL-17A, the founding member of the IL-17 family, and IL-17F are produced by several inflammatory cells, including activated T cells, in response to infectious and antigenic stimuli. Overexpression of IL-17A or IL-17F in the lungs results in induction of CXC chemokines and neutrophil recruitment. In a case-control study of 1125 unrelated Japanese subjects, a His161 to Arg161 (H161R) substitution in the third exon of the IL17F gene was shown to be associated with asthma and chronic obstructive pulmonary disease (COPD). Functionally, this variant failed to induce cytokines and chemokines, and interestingly, was able to antagonize the activity of wild-type IL-17F. These results provide an experimental basis for the observed genetic association with chronic inflammatory lung diseases, and also suggest the potential therapeutic utility of this antagonistic variant of IL-17F. Given that asthma and COPD are complex diseases involving a number of genetic and environmental factors, the genetic impact of IL-17F H161R with regard to the development of chronic airway inflammation likely varies among individuals with different genetic backgrounds and environmental exposures.  相似文献   
28.
食管癌的预后较差,切除术的致死率和致残率较高,术前正确分期对确定治疗方案尤为重要。PET是对CT、MRI、食管镜等常规检查的有益补充。受分辨率的影响,PET较难确定肿瘤的浸润程度,但对远处转移灶的诊断明显优于CT、MRI等常规检查,诊断复发性食管癌准确率较高,能有效鉴别手术瘢痕和复发,有效评价放疗、化疗的疗效。结合传统影像学检查,18F-氟脱氧葡萄糖PET及PET-CT能较为准确地进行术前分期,纠正不正确的治疗方案,改善食管癌患者的预后。  相似文献   
29.
Electrophysiological examinations were done on 20 patients aged 40–71 years with recently diagnosed high grade non-Hodgkin's lymphomas. General chemotherapy and intrathecal chemotherapy in order to prevent central nervous system (CNS) involvement were begun. On the first day of chemotherapeutic cycle patients received intrathecally methotrexate (ITMTX) and prednisolone. Electrophysiological study was carried out twice in each subject: before ITMTX injection and a day after injection. The study procedure included: a conventional nerve conduction examination (peripheral conduction velocity and compound muscle action potential amplitude), the F wave latency and amplitude measurement and F ratio (F-M-1/2M) calculation for peroneal and tibial nerve bilaterally. Results of the first and the second examinations were statistically compared by t-Student's test. No significant differences between values of estimated parameters were found. The study revealed no recent alterations in proximal, paraspinal motor conduction and motor neuron excitability due to antidromical activation after single ITMTX administration.  相似文献   
30.
The objective of this study was to establish to what extent muscle, cutaneous, and joint afferents alter the excitability of spinal and cortical motor neurons. This question was examined by studying the impact of electrical stimulation of the second and third digits, the median nerve at the wrist, and the recurrent thenar motor branch on the F/H and magneto-electrical cortical motor responses (MEPs) of the thenar muscles. The firing frequencies of single F/H motor unit action potentials were unaltered by the foregoing conditioning peripheral stimuli. MEPs conditioned by motor threshold stimulation of the median nerve at the wrist or the recurrent motor branch were significantly increased in size at conditioning to test intervals of 50 to 80 milliseconds. No significant change in MEP size resulted from conditioning stimulation of the digital nerves. We conclude that muscle afferents were primarily responsible for the increase in MEP size. Conditioning stimuli may allow examiners to assess central motor conduction where it would otherwise be impossible.  相似文献   
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