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11.
Magyar MT Szikszai Z Kertész Z Molnár S Uzonyi I Szíki GA Csiba L 《Ultrasound in medicine & biology》2007,33(8):1171-1178
Increased common carotid artery (CCA) intima-media thickness (IMT) measured by B-mode ultrasound is an early marker of the atherosclerotic process. Arterial calcification is not clearly understood. Using the particle-induced X-ray emission (PIXE) method, we have looked for the location in the artery wall where calcium accumulated in the early phase of atherosclerosis. Twelve segments of CCAs of deceased stroke patients were investigated. In-vivo, carotid duplex ultrasound was performed with bilateral CCA IMT measurement at plaque-free sections. During autopsy, segments of carotid arteries were collected and filled under pressure with a stained histologic embedding material. The frozen arteries were cut into 60-microm-thick slices. Calcium distribution maps from the segments of arteries were determined by PIXE method. IMT measured by ultrasound and calcium distribution maps measured by PIXE were compared. In our cross-sectional study, using the PIXE analysis and ultrasound images, we could demonstrate early calcium accumulation in the media layer. Our results have also shown a significant relationship between calcium content of distributional maps measured by PIXE analysis and corresponding IMT on B-mode ultrasound images of human CCAs. 相似文献
12.
To achieve desired public health outcomes, state agencies can choose among several legal mechanisms; however, no "best practice" guidelines are available to help them choose the most effective mechanism for a given situation. This article offers such guidance by comparing the relative advantages and disadvantages of laws, regulations, policies, and contracts. Factors compared include flexibility, the need for legislative involvement, the nature of the rulemaking process, enforceability, ability to reach target populations, and generalizability. Contracts, in particular, are described as an effective but underutilized mechanism for achieving successful public health outcomes. 相似文献
13.
A 49-year-old man underwent transthoracic echocardiography for atypical chest pain. A dilated coronary sinus was found and venous contrast echocardiography raised the suspicion of absent right and persistent left superior vena cava. Transesophageal echocardiography showed no presence of right superior vena cava. The echocardiographic findings were confirmed by upper venous digital subtraction cavography. 相似文献
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Quinine, a blocker of neuronal cx36 channels, suppresses seizure activity in rat neocortex in vivo 总被引:4,自引:1,他引:3
PURPOSE: The selective contribution of neuronal gap junction (GJ) communication via connexin 36 (Cx36) channels to epileptogenesis and to the maintenance and propagation of seizures was investigated in both the primary focus and the mirror focus by using pharmacologic approaches with the 4-aminopyridine in vivo epilepsy model. METHODS: ECoG recording was performed on anesthetized adult rats, in which either quinine, a selective blocker of Cx36, or the broad-spectrum GJ blockers carbenoxolone and octanol were applied locally, before the induction or at already active epileptic foci. RESULTS: The blockade of Cx36 channels by quinine before the induction of epileptiform activity slightly reduced the epileptogenesis. When quinine was applied after 25-30 repetitions of seizures, a new discharge pattern appeared with frequencies >15 Hz at the initiation of seizures. In spite of the increased number of seizures, the summated ictal activity decreased, because of the significant reduction in the duration of the seizures. The amplitudes of the seizure discharges of all the patterns decreased, with the exception of those with frequencies of 11-12 Hz. The blockade of Cx36 channels and the global blockade of the GJ channels resulted in qualitatively different modifications in ictogenesis. CONCLUSIONS: The blockade of Cx36 channels at the already active epileptic focus has an anticonvulsive effect and modifies the manifestation of the 1- to 18-Hz seizure discharges. Our findings indicate that the GJ communication via Cx36 channels is differently involved in the synchronization of the activities of the networks generating seizure discharges with different frequencies. Additionally, we conclude that both neuronal and glial GJ communication contribute to the manifestation and propagation of seizures in the adult rat neocortex. 相似文献
15.
Antal M Regöly-Mérei A Meskó E Barna M Biró L Rurik I Soós A Gyömörei E Réti K Horváth Z Veresné Bálint M Pék Z Szépvölgyi J Nagy K 《Orvosi hetilap》2004,145(49):2477-2483
INTRODUCTION: The preliminaries of the cardiovascular diseases can be traced back to the childhood. The authors tried to find relationship between parents with early onset myocardial infarction (AMI) and incidence of risk factors for ischemic heart disease in their children as compared to respective data for families with no incidence of myocardial infarction. METHODS: The study population consisted of 38 persons with early onset AMI myocardial infarction (age < 55 y) and their 66 children, and 38 adult control subjects and their 33 children. In each person arterial blood pressure, body weight, body height, waist circumference were recorded and body mass index (BMI: kg/m2) was calculated. Eating habits and life style practices were recorded in a questionnaire in the case of each participant. Laboratory variables were determined in the blood sera as follows, glucose, triglycerides (Tg), total cholesterol (T-C), HDL-cholesterol, LDL-cholesterol, apolipoprotein-A, apolipoprotein-B, and lipoprotein (a). The atherogenic index (LDL-C/HDL-C) (LDL-cholesterol/HDL-cholesterol) was also calculated. STATISTICAL EVALUATION: Data were evaluated statistically using the SPSS for Windows 9. RESULTS: According to the mean BMI values all groups of parents belonged to the overweight category. The mean cholesterol levels of all adults were in the borderline high category. In males with early onset myocardial infarction sera concentrations of HDL-cholesterol and apolipoprotein-A were significantly lower, whereas triglyceride and atherogenic index were significantly higher than respective data for control parents. In all groups of parents, fasting mean serum glucose concentrations were higher than the reference value, serum total-cholesterol concentrations were in the borderline high category. In the daughter of the parents with early onset myocardial infarction had a higher atherogenic index than that of controls. Eating habits did not essentially differ between case vs. control families. Consumption of milk, dairy products, fruit and vegetables was insufficient in each group. Incidences of smoking for parents and children were 55% and 35% in the myocardial infarction group and 44% and 37% in the control group, respectively. Physical activity was completely insufficient in each group studied. CONCLUSION: Since no considerable differences were seen between the case vs control families in the parameters tested, therefore it is presumed that the offspring born to parents with or without early onset myocardial infarction are at equal risk to develop cardiovascular diseases unless lifestyle practices are profoundly changed. 相似文献
16.
A new natural compound, 9alpha,20-dihydroxyecdysone (1), and two known related compounds, 20-hydroxyecdysone and ecdysone, were isolated from the herb Silene italica ssp. nemoralis. Compound 1 is the first C-9 hydroxylated ecdysteroid with a cis-fused A/B ring junction to have been isolated from a plant source, and its structure was determined using a combination of spectroscopic techniques. 相似文献
17.
Notting IC Missotten GS Sijmons B Boonman ZF Keunen JE van der Pluijm G 《Current eye research》2006,31(9):775-785
Uveal melanoma develops in one of the most capillary-rich tissues of the body and is disseminated hematogenously. Knowledge of the nature and the spatiotemporal expression of angiogenic factors in uveal melanoma is essential to the development of new treatment strategies, especially with regard to improving survival. In this study, we measured the angiogenic potential of several angiogenic factors in different uveal melanoma cell lines, in an in vivo model, and in primary tumor material from patients with melanoma. Most uveal melanoma cell lines expressed vascular endothelial growth factor (VEGF)-A (isoforms 121, 165, 189), VEGF-B, VEGF-C, VEGF-D, and basic fibroblastic growth factor (b-FGF) to various extents. The expression of VEGF-A 121 was always higher than that of the other VEGF-A isoforms, suggesting that VEGF-A 121 is the most abundant VEGF-A isoform. All experimentally induced tumors expressed VEGF-A, VEGF-B, VEGF-C, VEGF-D, and basic fibroblastic growth factor (b-FGF). Similarly, significant amounts of mRNA for VEGF-B, VEGF-C, VEGF-D, and b-FGF were detected in uveal melanoma material from patients. In contrast, VEGF-A mRNA (121, 165, 189) was low (9/28) or not detectable in the tumor samples. The synthesis of VEGF-A 165 and b-FGF protein by various cell lines was measured by enzyme-linked immunosorbent assay (ELISA). Most uveal melanoma cell lines, but not normal melanocytes, strongly synthesized and secreted VEGF-A 165 and b-FGF during cell culture. Our data suggest that the expression of (lymph) angiogenic factors may play a causal role in the angiogenesis and progression of uveal melanoma and distant metastasis. 相似文献
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