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991.
颈椎病的影像学检查及其临床意义 总被引:1,自引:0,他引:1
目的探讨颈椎病的临床及影像学表现,以期提高对本病的认识。方法对86例颈椎病X线,CT,MR影像学表现进行分析。结果86例中,颈椎病主要影像学改变为颈椎生理曲度异常,椎体和钩突关节骨质增生,椎间隙变窄,椎管狭窄和颈部韧带骨化。结论颈椎病影像学改变具有一定的特征性,有助于颈椎病的诊断,为临床治疗提供了依据和参考价值。 相似文献
992.
What is the prognostic value of myocardial perfusion imaging using rubidium-82 positron emission tomography? 总被引:5,自引:0,他引:5
Keiichiro Yoshinaga Benjamin J W Chow Kathryn Williams Li Chen Robert A deKemp Linda Garrard Alexander Lok-Tin Szeto May Aung Ross A Davies Terrence D Ruddy Rob S B Beanlands 《Journal of the American College of Cardiology》2006,48(5):1029-1039
OBJECTIVES: The objective was to determine the prognostic value of rubidium-82 (82Rb) positron emission tomography (PET) myocardial perfusion imaging (MPI). BACKGROUND: 82Rb PET MPI accurately diagnoses coronary artery disease (CAD). However, there are limited data evaluating its prognostic value. METHODS: Follow-up (3.1 +/- 0.9 years) was obtained in 367 patients who underwent dipyridamole 82Rb PET MPI. Patients were divided into groups based on their summed stress score (SSS): group I, normal (<4); group II, mild (4 to 7); and group III, moderate (8 to 11) to severe (> or =12). RESULTS: There were significant differences among patients in the 3 SSS groups for hard events (cardiac death and myocardial infarction [MI]) (p < 0.001) and total cardiac events (hard events, revascularization and hospitalization) (p < 0.001). The annual hard events rates were 0.4%, 2.3%, and 7.0% in the normal, mild, and moderate-severe groups, respectively. In adjusted survival models, 82Rb PET SSS was the strongest predictor of total cardiac events and a significant predictor of hard events. Among patients referred for PET after 99mTc single-photon emission computed tomography, the annual total event rate was higher with abnormal versus normal SSS on PET (15.2% vs. 1.3%, p < 0.001). In patients with obesity, the annual total event rate was 11.1% with an abnormal scan and 1.5% with a normal scan (p < 0.001). CONCLUSIONS: This study shows that 82Rb PET MPI has significant prognostic value for predicting cardiac events, including death and MI. It also seems to have prognostic value in patients whose diagnosis remains uncertain after single-photon emission computed tomography MPI and in obese patients. The prognostic value of PET MPI may improve the management of cardiac patients. 相似文献
993.
994.
Efrat Rorman Chen Stein Zamir Irena Rilkis Hilla Ben-David 《Reproductive toxicology (Elmsford, N.Y.)》2006,21(4):458
Toxoplasma gondii (T. gondii) is the cause of toxoplasmosis. Primary infection in an immunocompetent person is usually asymptomatic. Serological surveys demonstrate that world-wide exposure to T. gondii is high (30% in US and 50–80% in Europe). Vertical transmission from a recently infected pregnant woman to her fetus may lead to congenital toxoplasmosis. The risk of such transmission increases as primary maternal infection occurs later in pregnancy. However, consequences for the fetus are more severe with transmission closer to conception. The timing of maternal primary infection is, therefore, critically linked to the clinical manifestations of the infection. Fetal infection may result in natural abortion. Often, no apparent symptoms are observed at birth and complications develop only later in life. The laboratory methods of assessing fetal risk of T. gondii infection are serology and direct tests.Screening programs for women at childbearing age or of the newborn, as well as education of the public regarding infection prevention, proved to be cost-effective and reduce the rate of infection.The impact of antiparasytic therapy on vertical transmission from mother to fetus is still controversial. However, specific therapy is recommended to be initiated as soon as infection is diagnosed. 相似文献
995.
第一极体不能精确定位人卵母细胞纺锤体 总被引:4,自引:0,他引:4
目的 观测人卵母细胞纺锤体的确切位置,从而指导今后的生殖医学临床工作。方法 应用纺锤体成像系统观测体外成熟及体内成熟组人卵母细胞纺锤体,测量卵子中心、纺锤体与第一极体之间形成的角度。比较两组结果的差异。结果 体外成熟组纺锤体与第一极体形成角度和体内成熟组存在显著差异(P=0.006)。结论 人卵母细胞的位置并不能准确定位卵母细胞纺锤体的位置。体外成熟组纺锤体与第一极体形成的角度要明显小于体内成熟组。应用纺锤体成像系统可以安全、有效地观察人卵母细胞纺锤体。 相似文献
996.
眶骨的改变在眶部疾病HR-MRI诊断中的作用 总被引:6,自引:0,他引:6
目的:探讨眶骨的影像学所见及其在眶部疾病诊断中的作用。方法:回顾性分析诊断明确的眶部疾病80例的HR-MRI影像表现。80例中良性囊肿18例,外伤6例,炎性疾病6例,蝶骨嵴脑膜瘤9例,其他肿瘤41例。磁共振扫描采用1.5T GE Signa及Siemens Magnetom Sp63磁共振扫描机,用眶部表面线圈,SE系列常规轴位、冠状位及矢状位扫描,部分病例行脂肪抑制及增强扫描。结果:正常眶骨的HR-MRI表现为结构完整,边缘光整,皮质骨在T1WI及。T2WI上均为无信号区。15例眶骨受压迫性改变全见于良性囊肿的病例,骨质增生改变主要见于蝶骨脑膜瘤,2例骨折见于外伤病例,21例骨质破坏大多见于不同的恶性肿瘤病变中。结论:不同的眶部病变对眶骨的影响有差异,良性囊肿主要表现为眶骨受压迫性改变,蝶骨脑膜瘤多表现为骨质增生,外伤病例伴有眶骨骨折,恶性肿瘤病例常伴有眶骨的破坏。眶骨的改变对眶部疾病HR-MRI的诊断和鉴别诊断有重要作用。 相似文献
997.
Chih-Hsien Chang Kuo-Hsien Fan Te-Jung Chen Wei-Chun Hsu Mei-Ling Jan Tung-Hu Tsai Pan-Fu Kao Chieh-Fu Chen Ying-Kai Fu Te-Wei Lee 《台湾医志》2004,103(11):876-881
BACKGROUND AND PURPOSE: Fluorine-18-2-deoxy-D-glucose (18F-FDG) has been used in the clinic as a diagnostic radiotracer for monitoring many kinds of tumors, but its value for monitoring fibrosarcoma is not well established. METHODS: In this study, the uptake of 18F-FDG in a fibrosarcoma-bearing mouse model was evaluated using the high resolution positron emission tomography (PET) system microPET. Tumor cells were implanted in 3 FVB/N mice, and static microPET scanning was performed on day 1, 7, 12 and 15 after implantation. A dynamic microPET image was scanned on day 12 to determine the 18F-FDG uptake in 3 other tumor-bearing mice. Time-activity curves were plotted by drawing regions of interest in the tumor, liver, kidneys and muscles. The mice were sacrificed after dynamic microPET imaging and whole-body autoradiography (WBAR) was performed. For biodistribution study, 9 tumor-bearing mice, 3 per experimental group, were studied at 3 time points and the results were compared with the static microPET images. RESULTS: MicroPET images suggested that 18F-FDG could be used to monitor the growth of tumors 7 days after implantation. Dynamic scans of 18F-FDG uptake reached a plateau in the tumor after 20 minutes on day 12 after implantation. Both microPET and WBAR revealed evidence of tumor necrosis. The results of biodistribution and WBAR agreed with those from microPET images. CONCLUSION: MicroPET was useful for monitoring the growth of fibrosarcoma and determination of the maximal uptake time point of 18F-FDG in tumors in this tumor-bearing mouse model. 相似文献
998.
Kevin L. Billups 《Current Sexual Health Reports》2004,1(4):137-141
Erectile dysfunction (ED) is often not considered in the same context as such traditional cardiovascular conditions as hypertension,
dyslipidemia, diabetes, or ischemic heart disease. The detection of ED might be one of the most powerful tools to help manage
cardiovascular disease in men. Clinical research suggests that the penile vascular bed is a sensitive indicator of early systemic
endothelial cell or smooth muscle dysfunction. ED could be one of the initial signs of oxidative stress that occurs before
the development of the structural, occlusive cardiovascular disease. ED is becoming a barometer of overall global cardiovascular
risk and should be viewed in this context rather than as “just a problem with the penis.” Asking men about ED as part of the
review of systems is an effective means of practicing preventive vascular medicine. 相似文献
999.
Itiswell knownthatimmune inflammatorymechanism playsanimportantroleinpsoriasis .Therelationshipbetweenchemokine ,receptorsandpsori asishasbeenconfirmed[1] .CCchemokineligand 2 0(CCL2 0 )isanewmemberinthefamilyof β chemokineandalsotheonlyligandofCCchemoki… 相似文献
1000.
目的:了解抗β2-受体的自身抗体在急性心肌梗死(AMI)时的变化规律.方法:以合成的人心脏β2-受体细胞外第二环表位肽段172-197氨基酸序列作为抗原,应用酶联免疫吸附(ELISA)方法,检测41例AMI患者,发病24小时、7天、2~4周时,血清中抗β2-受体自身抗体的阳性率,并与61例正常人的检测结果进行对比.结果:心肌梗死患者急性期抗β2-受体自身抗体的阳性率显著高于对照组(P<0.05);心肌梗死发病24小时时抗β2-受体自身抗体的阳性率(29.3%)明显低于发病2~4周时(56.1%)的检测结果(P<0.05);心肌梗死急性期心功能killip-1级者与killip-2级者比较,抗β2-受体自身抗体的阳性率无显著性差异.结论:抗β2-受体自身抗体存在于AMI患者血清中,且在发病2~4周内逐渐升高.该抗体的产生与心肌梗死急性期心功能状态无明显的相关性. 相似文献