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In a population-based telephone interview survey of 9,380 residents aged 12 to 29 yr in Washington County, Maryland, who reported having had a headache, 60% of females and 41% of males had had one or more headaches during the previous week; 14.4% of females and 6.0% of males in the study group had consulted a physician in the previous 12 months for a headache problem. The likelihood of consulting a physician differed according to the type of headache. Subjects with headache during the week before the interview meeting the criteria for certain migraine or certain mixed tension--migraine were twice as likely as subjects with all other types of headaches to consult a physician during the previous 12 months. Females with tension headache were considerably more likely than males with the tension headache to have consulted a physician during the previous 12 months. On the other hand, males with migraine headache during the previous week were more likely than females with migraine to consult a physician. Disability (defined as being absent from school or from work for all or part of the day) was relatively common among those subjects with a headache during the previous week (13.7% of females and 7.9% of males). However, even among those reporting disability as a result of their headache during the previous week, only 31% of females and 18% of males reported consulting a physician during the previous 12 months.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Thirty-two patients affected by monolateral breast cancer and five patients with benign mammary pathology were submitted to pre-operative lymphoscintigraphy by sub-areolar injection of nanocolloidal albumin with the aim of evaluating any axillary lymphonodular involvement. The 32 patients, affected by cancer, subsequently underwent a surgical operation so as to permit a pathological-anatomical study of the axillary cavity. A comparison between the clinical and instrumental examinations brought to light the much greater reliability of the latter which gave 87.5% of correct diagnoses. The authors emphasize the absence of false positive results and the excellent sensitivity of the method in bringing to light even limited involvements of the axillary lymphonodes. The authors believe that axillary lymphoscintigraphy deserves to be included in the pre-operative protocols which afford a correct staging of the disease and, consequently, a better assessment of the extent of the surgical action.  相似文献   
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The effects of magnetic resonance (MR) pulse sequences and timing parameters on tumor-liver contrast were studied in an animal model of metastatic liver cancer. Six spin-echo (SE), three inversion-recovery (IR), and four gradient-echo (GRE) sequences were evaluated at 0.6 T before and after injection of super-paramagnetic iron oxide. GRE techniques, irrespective of echo time and flip angle, showed the greatest change in signal intensity (enhancement) of the liver after administration of iron oxide. Single-acquisition GRE sequences (16 seconds) matched the contrast-to-noise ratio (C/N) performance of the most effective 6.4-minute SE sequences. Multiexcitation GRE sequences showed tumor-liver C/Ns per unit time that were significantly (P less than .05) higher than those achieved with SE and IR sequences. GRE sequences, which recruit intravoxel dephasing as an additional source of transverse relaxation enhancement (T2*), show a higher C/N per unit time and in this respect seem superior to SE and IR sequences for MR imaging with superparamagnetic iron oxide.  相似文献   
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目的:目前电磁辐射对生物体行为学方面的研究还很薄弱,设立不同磁场的强度和不同照射的周期,观察中频领域磁场照射对小鼠的自主活动和学习记忆的影响。方法:实验于2007-05-10/06-15在清华大学医学院和中国医学科学院药用植物研究所完成。①实验材料:磁场发生装置:中频交变磁场发生装置由清华大学工程物理系医学物理与工程研究所自主研发,可产生频率为40kHz,场强为28.8A/m,28.8kA/m的中频交变磁场。自主活动测试箱:中国医学科学院药用植物研究所提供,为一可封闭的金属箱,内置摄像头。4只黑色塑料测试桶分别置于箱子四角。水迷宫测试箱:中国医学科学院药用植物研究所提供。②实验动物及方法:将80只小鼠随机分为不同场强照射组和对照组。强磁场照射1组:11.6kA/m/40kHz,1h/d,连续照射7d。强磁场照射2组:11.6kA/m/40kHz,2h/d,连续照射7d。强磁场照射3组:11.6kA/m/40kHz,2h/d连续照射15d。弱磁场照射组:28.8kA/m/40kHz,2h/d,连续照射7d。对照组除了未放入磁场照射,其他条件与照射组一致。实验过程中对动物处置符合动物伦理学要求。③实验评估:观察其一般活动的改变,并采用自主活动测试箱和水迷宫测试箱进行测试,观察各组小鼠的自主活动和学习记忆的改变。结果:①一般行为观察:与对照组小鼠对比,经过中频交变磁场照射过的各组小鼠活跃度减低,毛色较差。强磁场照射3组(145G,2h/d,连续15d)于第11天和13天分别死亡1只。②自主活动检测结果:强磁场照射2,3组小鼠的运动路程、运动速度、运动时间明显低于对照组(P<0.05)。③水迷宫测试结果:在学习记忆检测阶段撤掉平台,发现各组动物2min内穿越平台原来所在象限的次数没有明显差别(P>0.05)。结论:中频交变磁场照射会给小鼠的自发活动造成一定影响,对学习记忆没有影响。  相似文献   
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