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1.
The efficacy of an instructional videotape about the interpretation of the plantar response was evaluated during a two week neurological clerkship. Experimental groups saw the videotape, control groups did not. All students (n = 65) assessed plantar responses of two to four different patients. Their judgment was compared with that of one senior neurologist. Only the students who had seen the videotape showed a significant improvement in performance on a second test (t-test, t = -2.26, p = 0.031). In addition, these students more frequently took account of the flexion synergy (Fisher exact test, p less than 0.001). Video can be an efficient tool in medical education.  相似文献   
2.
Oral N-acetylcysteine supplementation in nine young healthy females induced a quick and highly significant decrease in plasma homocysteine levels and an increase in whole blood concentration of the antioxidant glutathione. N-acetylcysteine impresses as an efficient drug in lowering homocysteine concentration and might be beneficial for individuals with hyperhomocysteinemia who are at increased risk of cardiovascular disease.  相似文献   
3.
Pre-eclampsia is a pregnancy-related multisystem disorder characterised by elevation of blood pressure and proteinuria, in which oxidative stress may play an important role. Blood pressure is partly controlled by O(-)(2) production by NADPH/NADH oxidase and recently it was shown that a C242T substitution in the p22phox gene was associated with coronary artery disease, in which elevated blood pressure and oxidative stress are also important pathophysiologic features. Therefore we studied the prevalence of the C242T polymorphism in the NADPH/NADH oxidase gene in women with pre-eclampsia and/or haemolysis, elevated liver enzymes and low platelets (HELLP) syndrome as compared with women with a normotensive pregnancy. DNA from control women (n = 78), women with pre-eclampsia (n = 40), HELLP syndrome (n = 9) or women with HELLP complicated by pregnancy-induced hypertension or pre-eclampsia (n = 46) were tested for the presence of the C242T polymorphism by polymerase chain reaction followed by restriction fragment-length polymorphism. The prevalence of the homozygous CC-genotype was similar in the patient groups compared with controls. The allele frequency of the T-allele was 31% in both control and patient groups. In conclusion the C242T polymorphism in the p22phox subunit of the NADPH/NADH oxidase gene is not associated with pre-eclampsia. Therefore, oxidative stress generated by NADPH/NADH oxidase probably does not play a role in the development of pre-eclampsia.  相似文献   
4.

Background

Atherosclerotic plaque characteristics may affect downstream myocardial perfusion, as well as coronary lesion severity.

Objectives

This study sought to evaluate the association between quantitative plaque burden and plaque morphology obtained using coronary computed tomography angiography (CTA) and quantitative myocardial perfusion obtained using [15O]H2O positron emission tomography (PET), as well as fractional flow reserve (FFR) derived invasively.

Methods

Two hundred eight patients (63% men; age 58 ± 8.7 years) with suspected coronary artery disease were prospectively included. All patients underwent 256-slice coronary CTA, [15O]H2O PET, and invasive FFR measurements. Coronary CTA-derived plaque burden and morphology were assessed using commercially available software and compared with PET perfusion and FFR.

Results

Atherosclerotic plaques were present in 179 patients (86%) and 415 of 610 (68%) evaluable coronary arteries. On a per-vessel basis, traditional coronary plaque burden indexes, such as plaque length and volume, minimal lumen area, and stenosis percentage, were significantly associated with impaired hyperemic myocardial blood flow (MBF) and FFR. In addition, morphological features, such as partially calcified plaques, positive remodeling (PR), and low attenuation plaque, displayed a negative impact on hyperemic MBF and FFR. Multivariable analysis revealed that the morphological feature of PR was independently related to impaired hyperemic MBF as well as an unfavorable FFR (p = 0.004 and p = 0.007, respectively), next to stenosis percentage (p = 0.001 and p < 0.001, respectively) and noncalcified plaque volume (p < 0.001 and p = 0.010, respectively).

Conclusions

PR and noncalcified plaque volume are associated with detrimental downstream hyperemic myocardial perfusion and FFR, independent of lesion severity.  相似文献   
5.
6.
Impulse control disorders (ICD) are relatively common in Parkinson's disease (PD) and generally are regarded as adverse effects of dopamine replacement therapy, although certain demographic and clinical risk factors are also involved. Previous single‐photon emission computed tomography (SPECT) studies showed reduced ventral striatal dopamine transporter binding in Parkinson patients with ICD compared with patients without. Nevertheless, these studies were performed in patients with preexisting impulse control impairments, which impedes clear‐cut interpretation of these findings. We retrospectively procured follow‐up data from 31 medication‐naïve PD patients who underwent dopamine transporter SPECT imaging at baseline and were subsequently treated with dopamine replacement therapy. We used questionnaires and a telephone interview to assess medication status and ICD symptom development during the follow‐up period (31.5 ± 12.0 months). Eleven patients developed ICD symptoms during the follow‐up period, eight of which were taking dopamine agonists. The PD patients with ICD symptoms at follow‐up had higher baseline depressive scores and lower baseline dopamine transporter availability in the right ventral striatum, anterior‐dorsal striatum, and posterior putamen compared with PD patients without ICD symptoms. No baseline between‐group differences in age and disease stage or duration were found. The ICD symptom severity correlated negatively with baseline dopamine transporter availability in the right ventral and anterior‐dorsal striatum. The results of this preliminary study show that reduced striatal dopamine transporter availability predates the development of ICD symptoms after dopamine replacement therapy and may constitute a neurobiological risk factor related to a lower premorbid dopamine transporter availability or a more pronounced dopamine denervation in PD patients susceptible to ICD. © 2014 International Parkinson and Movement Disorder Society  相似文献   
7.

Background

Recent studies have demonstrated improved diagnostic accuracy for detecting coronary artery disease (CAD) when myocardial blood flow (MBF) is quantified in absolute terms, but there are no uniformly accepted cutoff values for hemodynamically significant CAD.

Objectives

The goal of this study was to determine cutoff values for absolute MBF and to evaluate the diagnostic accuracy of quantitative [15O]H2O positron emission tomography (PET).

Methods

A total of 330 patients underwent both quantitative [15O]H2O PET imaging and invasive coronary angiography in conjunction with fractional flow reserve measurements. A stenosis >90% and/or fractional flow reserve ≤0.80 was considered obstructive; a stenosis <30% and/or fractional flow reserve >0.80 was nonobstructive.

Results

Hemodynamically significant CAD was diagnosed in 116 (41%) of 281 patients who fulfilled study criteria for CAD. Resting perfusion was 1.00 ± 0.25 and 0.92 ± 0.23 ml/min/g in regions supplied by nonstenotic and significantly stenosed vessels, respectively (p < 0.001). During stress, perfusion increased to 3.26 ± 1.04 ml/min/g and 1.73 ± 0.67 ml/min/g, respectively (p < 0.001). The optimal cutoff values were 2.3 and 2.5 for hyperemic MBF and myocardial flow reserve, respectively. For MBF, these cutoff values showed a sensitivity, specificity, and accuracy for detecting significant CAD of 89%, 84%, and 86%, respectively, at a per-patient level and 87%, 85%, and 85% at a per-vessel level. The corresponding myocardial flow reserve values were 86%, 72%, and 78% (per patient) and 80%, 82%, and 81% (per vessel). Age and sex significantly affected diagnostic accuracy of quantitative PET.

Conclusions

Quantitative MBF measurements with the use of [15O]H2O PET provided high diagnostic performance, but both sex and age should be taken into account.  相似文献   
8.
9.
The purpose of this study was to assess the reproducibility and clinical impact of positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) in patients with (suspected) recurrent melanoma. The clinical value of PET was prospectively measured in 58 consecutive patients referred for PET because of unresolved clinical questions after conventional work-up. Diagnostic understanding and therapy choice by referring physicians were evaluated before, directly after, and 6 months after PET. Observer agreement of PET readings was measured with respect to various parameters (interpretation, number and localization of lesions, 'clinically decisive' metastases), using intra-class correlation coefficients. FDG PET improved diagnostic understanding in 33 cases (57%). In six patients (10%), diagnostic understanding was solely based on PET information. According to the attending clinicians, PET contributed to a positive change of planned treatment in 23 patients (40%) and increased confidence in the chosen treatment in 23 (40%). Observer agreement of PET readings was very high (intra-class correlation coefficients were between 0.87 and 0.94). The diagnostic value related especially to the whole-body scan technique and the superior specificity, compared to conventional work-up. It is concluded that, in problematical cases with (suspected) recurrent melanoma, 18F-FDG PET had considerable impact on diagnostic understanding and management. Together with the excellent observer reliability, these results justify further studies to determine the optimal place of PET in routine diagnostic algorithms in recurrent melanoma.  相似文献   
10.
OBJECTIVE:To investigate an association between a family history of cardiovascular disease and severe preeclampsia and/or HELLP syndrome (Haemolysis, Elevated Liver enzymes, Low Platelets). METHODS: One hundred twenty-eight women with a history of severe preeclampsia and/or HELLP syndrome and 123 women with previous uncomplicated pregnancies only were included in the study. All participants completed questionnaires about diagnoses of cardiovascular diseases, hypertension, and hypercholesterolemia among their first-degree relatives, which were subsequently confirmed by the relatives' general practitioners. The main outcome measures were the prevalence of cardiovascular diseases, hypertension, and hypercholesterolemia among first-degree relatives of both groups. Statistical analysis was done using chi(2)-analysis. RESULTS:The prevalence of familial cardiovascular disease among women with a history of severe preeclampsia and/or HELLP syndrome (23%) compared to controls (19%) was not significantly different (OR 1.3, 95%CI 0.7-2.5). However, women with a history of severe preeclampsia and/or HELLP syndrome more often had one or more first-degree relatives with hypertension and/or hypercholesterolemia before the age of 60 years compared to controls (54% vs. 32%, respectively; OR 2.6, 95%CI 1.5-4.3). The prevalence of hypertension and hypercholesterolemia among first-degree relatives, irrespective of age, also was significantly higher among women with a history of severe preeclampsia and/or HELLP syndrome as compared to controls (60% vs. 42%, respectively; OR 2.0, 95%CI 1.2-3.4). CONCLUSION:Severe preeclampsia is associated with a positive family history of hypertension and/or hypercholesterolemia.  相似文献   
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