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多级图像对比度放大技术在膝关节摄影中的应用 总被引:1,自引:0,他引:1
目的:分析评价膝关节摄影中多级图像对比度放大技术(MUSICA)参数设定的成像效果,为实际临床应用提供理论指导。方法:随机抽取膝关节侧位软拷贝图像70例,以骨皮质、骨小梁、肌间隙、髌上囊、皮下脂肪为比对目标,由三位观察者对其显示情况进行分析,并对结果进行统计分析。结果:MUSICA处于较小值(0~2)时,适合于软组织显示,但图像锐利度欠缺;处于较高值时(4~6)适合于观察骨皮质、小梁等细节信息,但较多地出现伪影,共25例;处于2~4时整体影像对比度适中,如实反映人体密度结构。结论:作图像处理时应将MUSICA为2~4设定为常规,实际应用通常情况下可以选择该处理方法,但应根据具体要求适当调整MUSICA参数值。 相似文献
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Effects of cytokines and R-837, a cytokine inducer, on UV-irradiation augmented recurrent genital herpes in guinea pigs. 总被引:1,自引:0,他引:1
We have recently reported that latently HSV-2-infected guinea pigs exhibit a three- to four-fold increase in recurrent lesions after exposure to ultraviolet radiation (UV), allowing rapid evaluation of antiviral drugs in treating recurrent HSV disease. In this report we examine the effect of alpha interferon (IFN-alpha), interleukin-2 (IL-2), and a cytokine inducer (R-837) on UV-induced recurrent genital herpes. We have previously shown that topical R-837 is a biologic response modifier with no in vitro anti-HSV activity, but with potent anti-HSV activity in vivo due to cytokine induction and enhancement of cell-mediated immune responses. Three-day regimens of intravaginal R-837, or five-day intraperitoneal (i.p.) administration of IFN-alpha or of IL-2 each significantly reduced recurrent genital HSV-2 disease that occurred within 7 days of UV exposure, suggesting that cytokines or cytokine inducers may be useful in the treatment of recurrent HSV disease. This model using ultraviolet radiation to induce recurrent herpes simplex virus infection proved useful in the evaluation of immunoactive agents as putative antiviral drugs. 相似文献
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Najat C Daw Wayne L Furman Clinton F Stewart Lisa C Iacono Mark Krailo Mark L Bernstein Janet E Dancey Rose Anne Speights Susan M Blaney James M Croop Gregory H Reaman Peter C Adamson 《Journal of clinical oncology》2005,23(25):6172-6180
PURPOSE: Epidermal growth factor receptor is expressed in pediatric malignant solid tumors. We conducted a phase I trial of gefitinib, an epidermal growth factor receptor tyrosine kinase inhibitor, in children with refractory solid tumors. PATIENTS AND METHODS: Gefitinib (150, 300, 400, or 500 mg/m2) was administered orally to cohorts of three to six patients once daily continuously until disease progression or significant toxicity. Pharmacokinetic studies were performed during course one (day 1 through 28). RESULTS: Of the 25 enrolled patients, 19 (median age, 15 years) were fully evaluable for toxicity and received 54 courses. Dose-limiting toxicity was rash in two patients treated with 500 mg/m2 and elevated ALT and AST in one patient treated with 400 mg/m2. The maximum-tolerated dose was 400 mg/m2/d. The most frequent non-dose-limiting toxicities were grade 1 or 2 dry skin, anemia, diarrhea, nausea, and vomiting. One patient with Ewing's sarcoma had a partial response. Disease stabilized for 8 to > or = 60 weeks in two patients with Wilms' tumor and two with brainstem glioma (one exophytic). At 400 mg/m2, the median peak gefitinib plasma concentration was 2.2 microg/mL (range, 1.2 to 3.6 microg/mL) and occurred at a median of 2.3 hours (range, 2.0 to 8.3 hours) after drug administration. The median apparent clearance and median half-life were 14.8 L/h/m2 (range, 3.8 to 24.8 L/h/m2) and 11.7 hours (range, 5.6 to 22.8 hours), respectively. Gefitinib systemic exposures were comparable with those associated with antitumor activity in adults. CONCLUSION: Oral gefitinib is well tolerated in children. Development of the drug in combination with cytotoxic chemotherapy will be pursued. 相似文献
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以链脲佐菌素制备糖尿病大鼠模型,造模后以还原型谷胱甘肽(GSH)治疗12周,结果显示GSH治疗组较糖尿病组心肌组织病理学损害改善,NF—κB活性降低,诱导型一氧化氮合酶表达下降。 相似文献
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Development, reliability, and validity of a dissociation scale 总被引:20,自引:0,他引:20
Dissociation is a lack of the normal integration of thoughts, feelings, and experiences into the stream of consciousness and memory. Dissociation occurs to some degree in normal individuals and is thought to be more prevalent in persons with major mental illnesses. The Dissociative Experiences Scale (DES) has been developed to offer a means of reliably measuring dissociation in normal and clinical populations. Scale items were developed using clinical data and interviews, scales involving memory loss, and consultations with experts in dissociation. Pilot testing was performed to refine the wording and format of the scale. The scale is a 28-item self-report questionnaire. Subjects were asked to make slashes on 100-mm lines to indicate where they fall on a continuum for each question. In addition, demographic information (age, sex, occupation, and level of education) was collected so that the connection between these variables and scale scores could be examined. The mean of all item scores ranges from 0 to 100 and is called the DES score. The scale was administered to between 10 and 39 subjects in each of the following populations: normal adults, late adolescent college students, and persons suffering from alcoholism, agoraphobia, phobic-anxious disorders, posttraumatic stress disorder, schizophrenia, and multiple personality disorder. Reliability testing of the scale showed that the scale had good test-retest and good split-half reliability. Item-scale score correlations were all significant, indicating good internal consistency and construct validity. A Kruskal-Wallis test and post hoc comparisons of the scores of the eight populations provided evidence of the scale's criterion-referenced validity.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献