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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.
本文提出了我国医疗器械产业中数字化技术发展中存在的主要问题,并分析了问题产生的原因。 相似文献
3.
H. David Banta Inger Schou Hindrik Vondeling Ardine De Wit 《Lasers in medical science》1992,7(1-4):9-21
This article reports on the results of a project evaluating effectiveness and cost-effectiveness of laser applications in
health care. The literature was collected, emphasizing well-designed clinical trials and cost-effectiveness analyses. Few
randomized clinical trials (RCTs) have been done outside the specialty of ophthalmology. Even fewer cost-effectiveness studies
have been done, despite the frequent claims of cost-effectiveness in the medical literature. Review papers were commissioned,
and a group of laser experts, economists, and policy-analysts met for 2 days to discuss the policy implications of lasers.
The main conclusion from the conference is that inappropriate and unskilled use of lasers is presently the greatest problem
with their application in health care. 相似文献
4.
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
5.
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
6.
7.
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
8.
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
9.
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
10.
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