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Background

The circle of Willis is an important source of collateral blood flow to maintain adequate cerebral perfusion, particularly in the posterior circulation. Some studies report a relationship between incomplete circle of Willis and migraine, whereas other studies show no difference between the prevalence of incomplete circle of Willis in migraineurs and controls. In the present study we compared the prevalence of incomplete circle of Willis in female migraine patients without aura to female healthy non-migraine controls.Using 3-Tesla magnetic resonance angiography we recorded three-dimensional time-of-flight angiograms in 85 female participants (48 migraine patients without aura [median age 28 years] and 37 healthy controls [median age 25 years]). The images were subsequently analysed blindly by a neuroradiologist to detect incomplete circle of Willis.

Findings

We found no difference between the prevalence of incomplete circle of Willis in patients, 20/47 (43%), and controls, 15/37 (41%), p = 0.252. Post hoc analysis showed a significant relationship between age and prevalence of incomplete circle of Willis, p = 0.003.

Conclusion

We found no relationship between migraine without aura and incomplete circle of Willis.  相似文献   
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Objective

The purpose of this study was to review the literature to determine whether surface electromyography (EMG) is a reliable tool to assess paraspinal muscle fatigue in healthy subjects and in patients with low back pain (LBP).

Methods

A literature search for the period of 2000 to 2012 was performed, using PubMed, ProQuest, Science Direct, EMBASE, OVID, CINAHL, and MEDLINE databases. Electromyography, reliability, median frequency, paraspinal muscle, endurance, low back pain, and muscle fatigue were used as keywords.

Results

The literature search yielded 178 studies using the above keywords. Twelve articles were selected according to the inclusion criteria of the study. In 7 of the 12 studies, the surface EMG was only applied in healthy subjects, and in 5 studies, the reliability of surface EMG was investigated in patients with LBP or a comparison with a control group. In all of these studies, median frequency was shown to be a reliable EMG parameter to assess paraspinal muscles fatigue. There was a wide variation among studies in terms of methodology, surface EMG parameters, electrode location, procedure, and homogeneity of the study population.

Conclusions

The results suggest that there seems to be a convincing body of evidence to support the merit of surface EMG in the assessment of paraspinal muscle fatigue in healthy subject and in patients with LBP.  相似文献   
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BACKGROUND: Laparoscopic suturing has been regarded as an advanced operative task, and courses to develop this skill are aimed at senior trainees and consultants. This study evaluates the role of laparoscopic suturing courses in the modern operative training curriculum. METHODS: The performance of 9 senior operative trainees (course A) was compared to that of 14 junior operative trainees (course B) at identical, 2-day laparoscopic suturing courses. Pre- and post-course assessments measured time taken, dexterity, and quality for the placement of 1 intracorporeal suture on synthetic bowel. Post-course data was compared to the performance of a group of 6 experts. RESULTS: The median number of laparoscopic procedures carried out unassisted was 130 for surgeons on course A, and 0 for those on course B. At the pre-course assessment, senior trainees (course A) were significantly faster, more dexterous, and had higher checklist scores then those on course B. Both groups had improved significantly by the end of each the course. Post-course comparison between the 2 groups showed equivalent path length and checklist scores, although group A remained faster (P = .003) and made fewer movements (P = .033). Senior trainees had similar performance data to the group of expert surgeons, although this was not the case for junior trainees. CONCLUSIONS: Endoscopic suturing is a task that can be learned by operative trainees during short skills courses, regardless of baseline laparoscopic experience. Skills training in laparoscopic suturing should thus not be reserved only for those contemplating advanced laparoscopic operation.  相似文献   
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With the increasing life expectancy, osteoporosis is becoming a major worldwide health problem, more particularly in the Middle East region. Bone mineral density (BMD) of the hip, lumbar spine, and forearm was measured by dual X-ray absorptiometry (Lunar) in 2085 (25% men, 75% women) healthy Iranian subjects aged 20–88 yr. The prevalence of osteoporosis and osteopenia in at least one measured site in subjects aged 50 yr and older were 36.1% and 43.9% in women, and 24.5% and 70.8% in men, respectively. Among subjects younger than 50 yr, 49.6% of women and 59.6% of men had low bone mass, respectively. In addition, more than one third of subjects showed discordance between different sites of measurement. The high incidence of low bone density in young ages requires our proper attention and planning for prevention. Measurement of BMD in all three sites seems necessary and clinicians should look for possible causes of discordance between different sites of measurement and develop an appropriate strategy approaching to these patients.  相似文献   
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