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81.
Premature ventricular contractions (PVCs) are frequently seen in children with normal cardiac findings. The purpose of this study was to evaluate the characteristics and the prognosis of PVCs in children with normal heart. This study included 149 children with PVC who did not have systemic or cardiac disease. Their median age at diagnosis was 10 years (range 1 month to 17 years). Seventy-six children (51%) were symptomatic. Most of the patients had unifocal PVC, whereas 5 (3.1%) of them had multifocal PVCs. The patients were evaluated by repeated Holter recordings and exercise test. In the first Holter monitoring recordings, PVCs were in the form of isolated PVC in 122 (82%) patients, couplet-triplet in 14 (9%) patients and nonsustained ventricular tachycardia in 13 (9%) patients. The exercise test was performed in 105 (70.5%) patients. The frequency of PVCs decreased and disappeared in 65 (61.9%) children, increased in 8 (7.6%), and were unchanged during exercise in 32 (30.5%). There was no difference between the groups according to exercise response regarding PVC quantity. Fifty-two of 149 children (35%) were followed up for a median period of 22 months. After follow-up, PVCs of 25 of the 52 patients (48.1%) decreased and disappeared. We did not find any correlation between the frequency of PVC and treatment, age, gender or the PVC frequency decrease with exercise. In conclusion, PVCs in normal children have benign prognosis and during follow-up a considerable percent show improvement.  相似文献   
82.
Panic disorder in a child with recurrent chest pain   总被引:1,自引:0,他引:1  
A 10-year-old boy was admitted to the Pediatric Cardiology Unit with complaints of chest pain and dizziness. Physical examination did not show any pathologic signs. Family history revealed no heart disease and diagnosis of panic disorder (PD) in one of his family members. On follow-up, he was admitted to the pediatric emergency department several times with the same complaint. Organic etiologies of chest pain were excluded by extensive diagnostic work-up. He was referred to the Child and Adolescent Psychiatry Department for further work-up, and PD was diagnosed. A few weeks after starting paroxetine therapy, the frequency and the intensity of the chest pain attacks began to diminish. Early diagnosis of PD will avoid unnecessary investigations and prevent utilization of expensive health services, especially those performed in the emergency department. Physicians should consider that chest pain may be related to psychiatric disorders and refer their patient to mental health professionals for further management. Pharmacological therapy and cognitive-behavioral interventions are successfully used in the management of PD in children and adolescents.  相似文献   
83.
Placing a silicone collar around the rabbit carotid artery induces intimal thickening, an early stage in atherosclerosis and restenosis. We investigatedwhethertreatment with oral pranidipine, a new potent, long-lasting dihydropyridine calcium channel blocker (CCB), inhibited collar-induced intimal thickening in addition to the changes in vascular reactivity usually observed in this model. Pranidipine treatment did not inhibit collar-induced intimal thickening. Placing the collar around the carotid artery resulted in the characteristic changes in vascular reactivity, such as increased sensitivity to 5-hydroxytryptamine. Treatment with Nomega-nitro-L-arginine (100 microM) and pranidipine, however, did not affect collar-induced changes in vascular reactivity. From results of this and previous studies, we conclude that pranidipine does not prevent collar-induced intimal thickening or collar-induced changes in vascular reactivity. Not all CCBs prevent collar-induced intimal thickening, suggesting that the effects of these agents are not related to their chemical structure and/or their calcium channel-blocking actions.  相似文献   
84.
There are numerous approaches for exploring the lower lumbar vertebrae, and the anterior transperitoneal route is one of the most popular. Like all surgical techniques, this approach has advantages and disadvantages. It provides direct access to the target tissue through a small incision, exposes the anterior portion of the vertebrae well, and permits good visualization of the major vessels, thus reducing risk of vascular injury and life-threatening hemorrhage. However, compared to the extraperitoneal route, the transperitoneal approach carries higher risks for peritoneal complications. This article describes a new practical method for creating an extraperitoneal passageway or "window" during transperitoneal approaches to the lower lumbar vertebrae. Isolation of the peritoneal cavity and its contents with this technique can reduce peri- and postoperative abdominal complications.  相似文献   
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Coronary artery disease may coexist with aortoiliac occlusive disease, and concomitant revascularization procedures may be required. The ascending aorta may be used as the source of inflow to both the femoral and coronary arteries in patients who present with coronary artery disease and critical leg ischemia. We present here 2 patients in whom coronary artery bypass grafting and ascending aorta-to-bifemoral bypass operations were performed simultaneously.  相似文献   
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Oxidative stress has an important role in the development of multiorgan failure after major burn. This study was designed to determine the possible protective effect of experimental hypothyroidism in hepatic and gastrointestinal injury induced by thermal trauma. Sprague Dawley rats were administered saline or PTU (10 mgkg(-1) i.p.) for 15 days, and hypothyroidism was confirmed by depressed serum T(3) and T(4) concentrations. Under brief ether anesthesia, shaved dorsum of rats was exposed to 90 degrees C (burn group) or 25 degrees C (control group) water bath for 10s. PTU or saline treatment was repeated at the 12th hour of the burn. Rats were decapitated 24h after injury and tissue samples from liver, stomach and ileum were taken for the determination of malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity and collagen contents. Formation of reactive oxygen species in tissue samples was monitored by using chemiluminescence (CL) technique with luminol and lucigenin probes. Tissues were also examined microscopically. Tumor necrosis factor (TNF)-alpha and lactate dehydrogenase (LDH) were assayed in serum samples. Severe skin scald injury (30% of total body surface area) caused a significant decrease in GSH level, which was accompanied with significant increases in MDA level, MPO activity, CL levels and collagen content of the studied tissues (p<0.05-0.001). Similarly, serum TNF-alpha and LDH were elevated in the burn group as compared to control group. On the other hand, PTU treatment reversed all these biochemical indices, as well as histopathological alterations induced by thermal trauma. Our results suggest that PTU-induced hypothyroidism reduces oxidative damage in the hepatic, gastric and ileal tissues probably due to hypometabolism, which is associated with decreased production of reactive oxygen metabolites and enhancement of antioxidant mechanisms.  相似文献   
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