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991.
We report a case of anomalous origin of the right pulmonary artery from the ascending aorta that was diagnosed by fetal ultrasound at 21 weeks of gestation. The clue to the diagnosis was present in the three-vessel view, this being one of the views that we use for fetal cardiac screening. The anomaly was corrected surgically at 11 days of age. We discuss the importance of prenatal diagnosis in the management of this rare anomaly.  相似文献   
992.
Gastric tuberculosis presenting as a submucosal tumor   总被引:1,自引:0,他引:1  
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993.
994.

Purpose

Brugada syndrome is a hereditary disease linked with an increased risk of sudden death that may require an implantable cardioverter-defibrillator (ICD) in order to halt the arrhythmic events. The aim of this study was to identify possible triggers for appropriate ICD therapies in patients with Brugada syndrome, focusing on their past and current therapeutic profiles.

Methods

Thirty patients with high-risk Brugada syndrome, with ICD implanted at the Coimbra Hospital and University Center, were enrolled. Patients were questioned about their Brugada syndrome history, previous cardiac events, comorbidities, present and past medications, and physical activity. Patients were followed up during 5.8?±?5.3 years. The ICD was interrogated, and arrhythmic events and device therapies were recorded. The cohort who received appropriate ICD therapies was compared with the remaining patients to determine the potential link between clinical variables and potentially fatal arrhythmic events.

Results

More than half of the patients (53.3%) took at least one non-recommended drug, and 16.7% received appropriate ICD therapies, with a long-term rate of 4.0%/year. There was a tendency for more appropriate ICD therapies in patients who took unsafe drugs (85.7 versus 45.5%, p?=?0.062), and the mean time between unsafe drug intake and appropriate ICD therapies was 3.8?±?7.5 days.

Conclusions

This study revealed that the medical community is still unaware of the pharmacological restrictions imposed by Brugada syndrome. Patients who took non-recommended drugs seem to have a higher risk of ventricular arrhythmic events.
  相似文献   
995.
Peroral endoscopic myotomy (POEM) is an endoscopic alternative to surgical myotomy in patients with achalasia. This study aimed to evaluate the efficacy and clinical outcomes of POEM.A total of 20 patients with achalasia who underwent POEM between October 2016 and November 2017 were prospectively recruited. The intraoperative esophagogastric junction distensibility index (mm2/mm Hg) was measured pre- and post-myotomy using an endoluminal functional lumen imaging probe. Clinical response was defined as Eckardt score ≤3. Health-related quality of life was measured by the 36-item short-form health survey score.POEM was successfully completed in all cases. The median procedure time was 68.5 minutes (range 50.0–120.0), and the median myotomy length was 13 cm (range 11–18). Major adverse events were encountered in 2 cases. Overall, clinical responses were observed in all patients during a median follow-up of 11.9 months (range 1.2–26.2). Postoperative esophagogastric junction distensibility index was significantly higher than baseline (from 1.3 [range 0.8–6.9] to 6.3 [range 25–19.2], P < .001). The median Eckardt scores were decreased after POEM (5 [range 2–11] to 1 [range 0–3], P < .001), and the 36-item short-form health survey score was also improved significantly after POEM (67.5 [range 34.5–93.9] to 85.7 [range 53.4–93.3], P = .004).POEM is an effective treatment for achalasia, based on the improvement of both symptoms and objective measures.Clinicaltrial.gov NCT 02989883  相似文献   
996.
997.
To elucidate the mechanism of action of the calcium antagonist verapamil, S-T segment mapping, retrograde coronary flow and regional coronary resistance were studied in 28 dogs subjected to acute coronary occlusion. Retrograde coronary flow was measured directly through catheterization of the distal occluded coronary artery. Regional coronary resistance was calculated by dividing mean distal coronary pressure by coronary flow. Verapamil (0.8 mg/kg) administered intravenously to eight dogs 30 minutes before coronary occlusion significantly reduced S-T segment elevation as compared with occlusion alone (p < 0.025); heart rate and diastolic pressure were also reduced (p < 0.05) but systolic pressure remained essentially unchanged. When verapamil was given to seven dogs within 30 minutes after coronary occlusion, there was a significant increase in retrograde coronary flow (p < 0.05) and a decrease in regional coronary resistance (p < 0.05). Simultaneously, heart rate and heart rate-blood pressure product declined significantly (p < 0.05), suggesting a reduction in myocardial oxygen consumption. Systolic blood pressure was unaltered, and diastolic pressure decreased only transiently. In 13 control dogs there was no significant change in any of these variables during the observation period. Thus, verapamil during acute coronary occlusion protects the ischemic myocardium by both increasing perfusion and reducing myocardial oxygen consumption.  相似文献   
998.
Chronic inflammatory process plays an important, as still not clear, role in pathophysiology of coronary artery disease (CAD), especially in acute coronary syndromes. Chemokines are present in atherosclerotic plaques and are essential factors in the recruitment of leukocytes and stabilization of atherosclerotic lesions. The aim of the study was the evaluation of RANTES serum level in patients with stabile CAD and seeking for correlations between RANTES serum level and progression of atherosclerotic lesions. The study included 83 patients from 22 to 87 years old, 41 women (mean age 61,2 +/- 12,5) and 42 men (mean age 58,8 +/- 15,4), who were admitted to the Cardiology Department for coronarography. After coronarography the patients were separated in 4 groups according to the presence of atherosclerotic lesions. Patients with atherosclerotic lesions were also divided depending on the severity of anginal pains to CCS II or CCS III classes. Blood samples for the measurement of RANTES serum level were taken at baseline conditions on the day after the admittance to the hospital. RANTES serum level was measured by enzyme-linked immunoabsorbent assay (ELISA) kit system (Endogen, MA, USA). There was not statistically significant differance in RANTES serum level between patients with CAD and subjects without atherosclerotic lesions in coronary arteries with or without arterial hypertension. Significantly higher levels of RANTES were observed in patients with atherosclerotic lesions in coronary arteries and anginal pains in CCS II class, than in patients with atherosclerotic lesions in coronary arteries and anginal pains in CCS II class, as well as in subjects without atherosclerotic lesions (respectively 58.5 vs 42.1 pg/ml and 54.5 vs 41.9 pg/ml, p<0.01). Significant positive corellations were found in patients with CAD between RANTES serum level and systolic blood pressure (r Pearson 0,291, p<0.05), and cholesterol (R Spearman 0.289, p<0.05). In all patients analysis of regression found significant correlation between RANTES serum level and systolic blood pressure (p 0.296, B 0.391, p<0.007). These results may indicate the active implication of chemokines in the pathophysiology of atherosclerotic lesions.  相似文献   
999.
Vesicles have unique characteristics that enable the release of drugs as well as encapsulation while maintaining biocompatibility. A photo-polymerizable liposome composed of 1,2-bis(10,12-tricosadiynoyl)-sn-glycero-3-phosphocholine (23:2 DiynePC) has been investigated as vehicles for triggered delivery of drugs to cells. In this study, we confirmed for the first time that supported lipid bilayers (SLBs) prepared with a 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC)/DiynePC mixture generated pores ca. 100–300 nm in size on the membrane after UV polymerization. This direct observation was done by analyzing the SLBs formed with the DPPC/DiynePC mixture by employing atomic force microscopy (AFM) in a liquid environment. However, photo-polymerization did not occur in the 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC)/DiynePC mixed bilayer and pores were not formed. A theoretical study was performed to explore the phase behavior of the lipid mixtures. A coarse-grained model of DiynePC was developed that is comparable with the Martini force field; the parameters were validated against atomistic simulations. Transition from fluidic to gel phase was observed only when DiynePC was mixed with DPPC, whereas the DOPC mixture remained fluidic over the entire domain. This implies a correlation between the formation of DiynePC-rich gel phase domains and the generation of pores after polymerization. The size of the pores were found to be controlled by the amount of polymerizable lipid which results in higher release rate of encapsulated calcein from the vesicles with larger pores.

Nanopores generated upon photo-polymerization of the lipid membrane containing DiynePC were identified and their size was controllable.  相似文献   
1000.
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