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1.
Abstract Migraine without aura is typically considered a female condition. The purpose of this study was to determine if there have
been any changes in the female-to-male ratio of the disease over time. We included in the study all patients with migraine
without aura (n=3457) referred to the Parma University Headache Centre between 1976 and 1995. They were divided into subgroups with respect
to gender and year-range of onset of migraine (before 1960, in the 1960s, in the 1970s, in the 1980s, and between 1990 and
1995). Gender ratio ranged from 3.6:1 (in patients with onset before 1960) to 2.8:1 (in patients with onset in the 1980s),
with no statistically significant changes during the observation period. 相似文献
2.
Alain Djacoba Tehindrazanarivelo Jean Marc Visy Marie-Germaine Bousser 《Cephalalgia : an international journal of headache》1992,12(5):318-320
We report two patients with ipsilateral attacks of cluster headache and chronic paroxysmal hemicrania. The first patient, a 33-year-old man, started having attacks of chronic cluster headache at the age of 27. At 33, they were replaced by typical attacks of ipsilateral chronic paroxysmal hemicrania which showed a dramatic improvement with indomethacin 150 mg daily. After two days of complete remission, cluster headache attacks reappeared and persisted until verapamil, 360 mg a day, was added to indomethacin. The second patient, a 45-year-old man, first developed attacks of episodic cluster headache at the age of 35. At 44, he experienced ipsilateral typical attacks of chronic paroxysmal hemicrania, and two months later attacks of cluster headache. Under verapamil 240 mg daily, attacks of cluster headache disappeared, but those of chronic paroxysmal hemicrania increased in frequency until indomethacin 150 mg daily was added. These observations suggest a close relationship but not a similarity between cluster headache and chronic paraoxysmal hemicrania, and show the practical therapeutic interest of maintaining this distinction. 相似文献
3.
内蒙古赤峰地区鼠疫现状和流行趋势预测及控制措施的研究 总被引:36,自引:0,他引:36
赤峰地区于1948 ̄1996年发现了16632.2km^2鼠疫自然疫源地,分布于11个旗(县、区)。目前达到控制鼠疫面积13917.8km^2,占疫源地总面积的83.68%。选取与疫源地相关的12种量经因子进行聚类分析,结果可分为:1.疫源性长存区;2.动物鼠疫间断流行区;3.鼠疫动物病控制区;4.疫源性基本消除区。同时对措施进行了探讨。 相似文献
4.
5.
S Evers P Sörös R Brilla H Gerding I-W Husstedt 《Cephalalgia : an international journal of headache》1997,17(6):680-682
A 37-year old man developed an ipsilateral headache which fulfilled the criteria for cluster headache after orbital exenteration because of traumatic lesion of the bulb. The headache could be treated successfully by drugs usually applied in the therapy of cluster headache. Six similar cases of cluster headache after orbital exenteration could be identified in the literature suggesting that the eye itself is not necessarily part of the pathogenesis of cluster headache. We hypothesize that orbital exenteration can cause cluster headache by lesions of sympathetic structures. Possibly, these mechanisms are similar to those of sympathetic reflex dystrophy (Sudeck-Leriche syndrome) causing pain of the limbs. 相似文献
6.
Giuseppe Micieli Marco Magri Giorgio Sandrini Cristina Tassorelli Giuseppe Nappi 《Cephalalgia : an international journal of headache》1988,8(3):193-201
In this study the variations in pupil diameter induced by different stimuli (dark-light adaptation, light reflex, electric stimulation of the sural nerve) were investigated in episodic (in the active or remission phases) and in chronic cluster headache (CH) patients. Pupil size monitoring was performed with a monocular, infrared TV pupillometer, and sural nerve stimuli were applied after the pain threshold had been measured as the flexion reflex threshold of the biceps femoris muscle (RIII reflex). The results were compared with those obtained in patients with "peripheral" (third neuron) Horner's syndrome and in healthy sex- and age-matched controls. On the symptomatic side we found an impairment of pupil response to light flashes and nociceptive stimuli; similar findings were sometimes evident on the pain-free side, too. These results substantiate previous observations that in cluster headache a dysfunction of the integrative central nervous system pathways also exists intercritically and mostly bilaterally, involving both autonomic regulation and pain perception mechanisms. 相似文献
7.
在目前不能直接观测病人内部器官微循环改变的条件下,应用模糊聚类的理论和方法,对主要常见病有意义的的甲襞微循环改变进行聚类,同时参考国内外相关文献的结果,提出了主要常见病有意义的甲襞微循环改变群。在改变群中任意提出3、4、5、6、7、8项改变指标,形成改变组合,一种组合重复出现二次以上的重复率,随组合改变指标数的增多而减少(70.36%~4.36%)。将改变群分成重要指标和参考指标二类,从每类中提出三项形成组合,重复率仅为0.34%。说明组合方式的影响十分巨大。经过反复探索、大量实践,有可能找出对疾病的符合率较高、漏诊率较低、误诊率较小的最佳组合方式。 相似文献
8.
A common approach to the analysis of gene expression data is to define clusters of genes that have similar expression. A critical step in cluster analysis is the determination of similarity between the expression levels of two genes. We introduce a neural network-based similarity index as a non-linear similarity index and compare the results with other proximity measures for Saccharomyces cerevisiae gene expression data. We show that the clusters obtained using Euclidean distance, correlation coefficients, and mutual information were not significantly different. The clusters formed with the neural network-based index were more in agreement with those defined by functional categories and common regulatory motifs. 相似文献
9.
Salganik MP Hardie DL Swart B Dandie GW Zola H Shaw S Shapiro H Tinckam K Milford EL Wand MP 《Journal of immunological methods》2005,305(1):67-74
The blind panel collected for the 8th Human Leucocyte Differentiation Antigens Workshop (HLDA8; ) included 49 antibodies of known CD specificities and 76 antibodies of unknown specificity. We have identified groups of antibodies showing similar patterns of reactivity that need to be investigated by biochemical methods to evaluate whether the antibodies within these groups are reacting with the same molecule. Our approach to data analysis was based on the work of Salganik et al. (in press) [Salganik, M.P., Milford E.L., Hardie D.L., Shaw, S., Wand, M.P., in press. Classifying antibodies using flow cytometry data: class prediction and class discovery. Biometrical Journal]. 相似文献
10.
Hospital infections represent a major epidemiological problem. The first step in the detection of nosocomial infections consists in assessing the probability that two or more isolates from different patients are similar or different. Many methods are available for typing purposes. Among these, antibiotic susceptibility patterns do not need extra cost or extra work and are available on line every moment they are needed. A mathematical technique of elaboration is proposed for disk zone sizes, in order to assess the probability of two or more clinical isolates to be the same strain. Antibiograms performed according to Kirby-Bauer are evaluated detecting zone sizes by a computer controlled device and then submitted to cluster analysis. Similarity of strains is reported in a dendrogram, in which strains are successively fused. Strains that share a common susceptibility pattern are considered a cluster . At last, epidemiological maps are constructed for each group of strains, in which all the isolates are reported, ordered for patients, plotted on the day the specimen was collected, drawn in a different shape according to the source of specimen, and shadowed by the pattern of its cluster. This method of reporting data directly allows to detect cross infections among patients and can be used as a first typing step before other more expensive procedures.Corresponding author. 相似文献