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1.
There has been tremendous progress in treatment of heart disease in children. Device therapy is increasingly being used in acyanotic congenital heart disease, while surgical results have improved significantly to give smile to many cyanotic heart disease children and their parents. This article makes an attempt to increase awareness of general pediatricians about common congenital heart diseases.  相似文献   
2.
Hepatocellular carcinoma (HCC) is a complex and heterogeneous tumor most commonly associated with underlying chronic liver disease, especially hepatitis. It is a growing problem in the United States and worldwide. There are two potential ways to prevent HCC. Primary prevention which is based on vaccination or secondary prevention involving agents that slow down carcinogenesis. Several pathways have been thought to play a role in the development of HCC; specifically, those involving vascular endothelial growth factor (VEGF)‐mediated angiogenesis, WNT, phosphatidylinositol 3‐kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR), AMP‐activated protein kinase (AMPK), and c‐MET. Currently, there are only a limited number of drugs which have been proven as effective treatment options for HCC and several clinical trials are testing drugs which target aberrations in the pathways mentioned above. In this review, we discuss currently approved therapies, monotherapies and combination therapy for the treatment of HCC.  相似文献   
3.
Aortopulmonary window is an uncommon congenital cardiac defect. Most infants presenting with aortopulmonary window will require conventional surgical repair. Experience with transcatheter closure of aortopulmonary window is limited. We report the case of a 9-year-old girl with aortopulmonary window, in whom transcatheter closure was performed successfully using Amplatzer ductal occluder device.  相似文献   
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5.
A low-sulfated chondroitin sulfate proteoglycan (CSPG) has been shown to be the receptor for the adherence of Plasmodium falciparum-infected red blood cells (IRBCs) in human placenta. Recently, hyaluronic acid (HA) has been suggested as an additional receptor even though IRBC binding to HA and the presence of HA at locations where IRBCs adhere in the placenta have not been established. In this study, we investigated whether HA is also a receptor for IRBC binding. IRBCs from infected placentas as well as those from different laboratory strains could bind to CSPG but not to HA. In a cell depletion assay, IRBCs from infected placentas could bind quantitatively to CSPG. Although CSPG is present both in the intervillous space and on the syncytiotrophoblast surface, HA is absent in these locations. These data conclusively demonstrate that CSPG, but not HA, is a receptor for IRBC adherence in the placenta. Our data also show, for the first time, that the IRBC-binding CSPG in the placenta is of fetal origin and that, in P. falciparum-infected placentas, the CSPG level is significantly increased, which could exacerbate IRBC adherence and placental pathogenesis. These results have important implications for the development of anti-IRBC adhesion-based vaccine for pregnancy-associated malaria.  相似文献   
6.
Kawasaki disease (KD) is an acute medium vessel vasculitis seen in children. The most significant long-term complication is related to coronary artery abnormalities. Use of intravenous immunoglobulins, however, has led to significant reduction in incidence of coronary aneurysms. What is more alarming is the fact that higher risk of cardiovascular disease is seen in even those children who do not have coronary artery aneurysms during subacute phase. Various factors like abnormal lipid profiles, abnormal vessel wall reactivity and endothelial dysfunction have been implicated for this. Carotid intima-media thickness (cIMT) has been used as a surrogate marker for atherosclerosis. This study was planned to evaluate cIMT in children with KD. Twenty-seven children with diagnosis of KD at least 1 year prior to enrolment were evaluated for cIMT at enrolment and then after 3 months. Fasting lipid profile was done for all patients. Mean cIMT was significantly higher in children with KD compared to controls. In lipid profiles, undesirable HDL-C and triglyceride levels were seen in 2 and 3 children, respectively. Undesirable and borderline LDL-C levels were seen in 1 and 2 patients, respectively. Undesirable and borderline total cholesterol levels were seen in 1 and 3 patients, respectively. Higher cIMTs were seen in our cohort of KD patients. Proatherogenic abnormalities in lipid profile were seen in a few patients. Both abnormalities may predict a higher risk of atherosclerosis in future. The results of this study need to be replicated on a larger study sample and over longer follow-up periods.  相似文献   
7.
Periodic practice is needed for newly trained robotic surgeons to maintain skills during periods of robotic inactivity. The current study was performed to determine whether virtual robotic skill maintenance can serve as an adequate substitute for practice on a surgical robot. Eleven surgical residents with no prior robotic training were trained to a level of robotic proficiency with inanimate models, including a needle driving pad, a running suture pad, and ring placement on a rocking peg board. After reaching proficiency, each resident was tested on a complex tissue closure task. For the next 8 weeks, the only robotic activity was biweekly virtual robotic skills maintenance. After 8 weeks, the residents performed the tissue closure task twice with the robot, followed by evaluation on the inanimate models used to reach proficiency. Repeated-measures statistical analyses were used to compare between the three tissue closure trials and between the final test at week 0 and the evaluation at week 8 for the other inanimate models. Time to complete the tissue closure task was more than 20 % lower for the second evaluation at 8 weeks than for the other two trials (p < 0.05). Residents maintained their skills for needle driving, but times for suture running and rocking peg board increased by more than 20 % at 8 weeks (p < 0.01). Virtual practice shows promise for maintaining robotic skills. Following a warm-up period, some skills may actually improve with biweekly virtual practice, but skill retention is selective, so further improvements are needed.  相似文献   
8.
A new method was investigated for improving the efficiency of ECG-gated coronary magnetic resonance angiography (CMRA) by accurate, automated tracking of the vessel motion over the cardiac cycle. Vessel tracking was implemented on a spiral gradient-echo pulse sequence with sub-millimeter in-plane spatial resolution as well as high image signal to noise ratio. Breath hold 2D CMRA was performed in 18 healthy adult subjects (mean age 46 +/- 14 years). Imaging efficiency, defined as the percentage of the slices where more than 30 mm of the vessel is visualized, was computed in multi-slice spiral scans with and without vessel tracking. There was a significant improvement in the efficiency of the vessel tracking sequence compared to the multi-slice sequence (56% vs. 32%, P < 0.001). The imaging efficiency increased further when the true motion of the coronary arteries (determined using a cross correlation algorithm) was used for vessel tracking as opposed to a linear model for motion (71% vs. 57%, P < 0.05). The motion of the coronary arteries was generally found to be linear during the systolic phase and nonlinear during the diastolic phase. The use of subject-tailored, automated tracking of vessel positions resulted in improved efficiency of coronary artery illustration on breath held 2D CMRA.  相似文献   
9.
The study was institutional review board approved and Health Insurance Portability and Accountability Act compliant. All subjects provided informed consent. Three-dimensional breath-hold coronary magnetic resonance (MR) angiography with use of steady-state free precession was performed in 12 patients up to 20 minutes after 0.2 mmol gadolinium-based contrast material per kilogram of body weight was administered. Within 24 heartbeats, a spatial resolution of up to 1.0 x 1.2 x 2.0 mm was achieved. Sixty-five (82%) of the 79 visualized coronary artery segments had a grade of 3 or 4 on a four-point scale of depiction in which grade 4 indicated excellent depiction. Twenty-seven percent (n = 21) of the 79 segments were assigned a grade of 4; 56% (n = 44), a grade of 3; 16% (n = 13), a grade of 2; and 1% (n = 1), a grade of 1. Coronary MR angiography performed as part of a first-pass myocardial perfusion and viability assessment MR imaging examination is feasible and does not involve additional imaging time.  相似文献   
10.
Coronary artery magnetic resonance imaging strategies have tended to focus on the use of a single method performed during either breath-holding or free-breathing for all patients. However, significant variations exist among patients in terms of breath-holding ability and respiratory regularity that make the use of a single technique alone not universally successful. Therefore, it is prudent to make available a number of magnetic resonance imaging methods such that an appropriate respiratory motion reduction strategy can be tailored to suit the patient's respiratory pattern and characteristics. A tailored approach that can draw on different image acquisition techniques for coronary artery imaging is presented. A decision tree is proposed to triage patients into imaging regimes with the greatest probability of success, according to the patient's ability to breath-hold or exhibit steady respiration. Methods include volume free-breathing acquisitions using navigator echoes for respiratory monitoring in the 8- to 10-min scan time range, two-dimensional spiral navigators (2- to 3-min scan time), breath-held multislice and vessel-tracking spirals (16- to 20-second scan time), and real-time imaging approaches incorporating adaptive signal averaging. The development of multiple acquisition strategies substantially improves the opportunities to generate high-quality, diagnostic images of the coronary arteries.  相似文献   
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