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Moises Rodriguez-Gonzalez Antonio Moruno Tirado Reza Hosseinpour Jose Santos de Soto 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2015,42(4):350-356
Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital condition. It responds well to early diagnosis and treatment, but otherwise the prognosis is poor. We present our case series of 12 patients (mean age, 2 ± 2.58 yr; age range, 2 mo–8 yr), emphasizing the diagnostic process and discussing our surgical results. The diagnosis of ALCAPA should be suspected in infants who have dilated cardiomyopathy with electrocardiographic changes that suggest ischemia, and in older children who have isolated mitral regurgitation. When clinical suspicion is high, the results of 2-dimensional echocardiography combined with color-flow Doppler studies in expert hands can establish the diagnosis, thus avoiding angiography in critically ill infants. The treatment of choice in our patients was transfer and reimplantation of the left coronary artery onto the ascending aorta. There were 2 deaths: both were infants in extremis who underwent emergency surgery. An older child with severe ventricular dysfunction was given mechanical ventricular assistance and then heart transplantation. As of this report, all 10 survivors remained well and asymptomatic. 相似文献
3.
Saeed Reza Mehrpour Mohammadreza Kargar Alireza Mobasseri 《Journal of hand and microsurgery》2015,7(2):340-342
The floating metacarpal bone is a result of simultaneous fracture-dislocation of both carpometacarpal and metacarpophalangeal joints. This rare entity may be associated with other hand injuries. Here we present a floating index metacarpal with concomitant 3rd–5th carpometacarpal fracture-dislocations. Excellent functional short-term result was achieved after open metacarpopha langeal reduction and closed carpometacarpal reduction and percutaneous pinning. 相似文献
4.
Michelle Linda Ferderbar Thomas E. Doyle Reza Samavi David Koff 《Journal l'Association canadienne des radiologistes》2019,70(2):119-124
Several regulatory bodies have agreed that low-dose radiation used in medical imaging is a weak carcinogen that follows a linear, non-threshold model of cancer risk. While avoiding radiation is the best course of action to mitigate risk, computed tomography (CT) scans are often critical for diagnosis. In addition to the as low as reasonably achievable principle, a more concrete method of dose reduction for common CT imaging exams is the use of a diagnostic reference level (DRL). This paper examines Canada's national DRL values from the recent CT survey and compares it to published provincial DRLs as well as the DRLs in the United Kingdom and the United States of America for the 3 most common CT exams: head, chest, and abdomen/pelvis. Canada compares well on the international scale, but it should consider using more electronic dose monitoring solutions to create a culture of dose optimization. 相似文献
5.
Results of Transplanting Developing Third Molars as Part of Orthodontic Space Management 总被引:2,自引:0,他引:2
Oskar Bauss Reza Sadat-Khonsari Werner Engelke Bärbel Kahl-Nieke 《Journal of orofacial orthopedics》2002,63(6):483-492
PATIENTS AND METHOD: The aim of the present study was to contribute to a more accurate indication and better integration of developing third molar transplantation into orthodontic space management, using the results gleaned from the authors' own pool of patients. For this purpose, a clinical and radiographic examination of 61 transplanted developing molars in 57 patients was carried out after an average of 3.3 years. RESULTS: The overall success rate was 85%. Failure was due in 10% of cases to impaired periodontal healing (inflammatory root resorption, ankylosis, or increased pocket probing depths) and in 5% of cases to insufficient or arrested postoperative root development accompanied by increased transplant mobility. The incidence of postoperative cessation of further root development was significantly higher (p = 0.011) in transplants at early developmental stages, which also had a negative impact on the final root length, the crown-root ratio and the mobility values of these transplants. CONCLUSIONS: The transplantation of developing third molars should be given stronger consideration in treatment plans for orthodontic space management although it represents a real alternative to orthodontic space closure only in exceptional cases. However, unlike implantological or prosthodontic treatment, it offers an opportunity to replace a missing or non-retainable tooth with a patient's own vital and fully functional tooth, provided the appropriate transplant is selected. 相似文献
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Eric Lim Ziad Ali Ayyaz Ali Reza Motalleb-Zadeh Christopher Jackson Seok Ling Ong James Halstead Linda Sharples Jayan Parameshwar John Wallwork Stephen R Large 《The Journal of heart and lung transplantation》2005,24(8):983-989
BACKGROUND: To ascertain survival of ischemic advanced heart failure patients by treatment allocation, we examined the outcome of transplant assessment patients allocated to medical therapy, high-risk conventional surgery, or transplantation. METHODS: Patients were identified from the Papworth transplant database and excluded if primary etiology was not ischemic. Grouping was undertaken according to treatment allocation at initial assessment, and analysis was performed by intention to treat. Survival was computed from the time of assessment and Cox regression used to stratify patients according risk with the Heart Failure Survival Score. RESULTS: From May 1993 to September 2001, a total of 755 patients were admitted for transplant assessment, with 348 (46.1%) identified as having heart failure of ischemic origin. Variables required for calculation of the Heart Failure Survival Score was available in 273 patients (78.4%), and 20 patients (7.3%) were lost to follow-up. Of the remaining 253 patients, 89 (35.2%) were allocated to medical therapy, 32 (12.6%) to surgery, and 132 (52.2%) to transplantation. The relative risk (95% confidence limit) of death compared with medical therapy was 0.62 (0.28, 1.40) for surgery and 0.38 (0.24, 0.61) for transplantation in medium- to high-risk patients. For low-risk patients, the relative risks for death compared with medical therapy were 1.87 (0.63, 5.60) for surgery and 1.97 (0.79, 4.96) for transplantation. CONCLUSIONS: Transplantation improved survival of medium- and high-risk patients compared with medical therapy. In the low-risk group, this was not evident. However, repeated assessment of risk is required because the hazard for death rises steadily after the third year in these patients. 相似文献
9.
Abbas Pardakhty Alireza Foroumadi Mehdi Hashemi Saeed Rajabalian Mahmoud Reza Heidari 《Toxicology in vitro》2007,21(6):1031-1038
We examined the cytotoxic potential of nine N-[2-substituted-2-(2-thienyl)ethyl] piperazinyl quinolone derivatives on human oral epithelial mouth carcinoma (KB) and human squamous carcinoma (A431) cell lines. Phototoxic properties of these compounds were also evaluated by mouse 3T3 fibroblast under ultraviolet-A (UVA) irradiation. The percent of cell viability was evaluated by MTT assay. Compound 6 having a 4-[2-(phenylmethoxyimino)-2-(2-thienyl)ethyl] group attached to N4 position of piperazine ring of enoxacin showed the highest cytotoxicity potential on both A431 and KB cell lines (IC50 of 3.11+/-0.52 and 4.91+/-1.94 microg/ml, respectively). While some of the other tested compounds exhibited clear phototoxic potential in 3T3 cell line, compound 6 showed only a minor potential of phototoxicity. These findings suggest the high potential of 4-[2-(phenylmethoxyimino)-2-(2-thienyl)ethyl] derivative of enoxacin as a cytotoxic compound with low potency of phototoxic reactions. The mentioned chemical was identified to be of special interest for further characterization. 相似文献
10.
Joyce Toral William Hu Donald Critchett Andrew J. Solomon James E. Barrett Patricia T. Sokol M. Reza Ziai 《The Journal of pharmacy and pharmacology》1995,47(7):618-622
The 5-HT3-receptor antagonist, ondansetron, has been shown to have positive effects in selected in-vivo models of memory impairment and anxiety. The exact mechanisms underlying such bioactivities are unknown. In the present work, an 86Rb efflux bioassay was used to show that ondansetron has a unique ability to block voltage-gated potassium channels in TE671 human neuroblastoma cells. This intrinsic potassium-channel-blocking (KCB) property is relatively weak (IC50 20 (M), but is not shared by other 5-HT3-receptor ligands including zatosetron, MDL 72222, LY 278, 584, zacopride, 1-phenylbiguanide, and ICS 205–930 (tropisetron). Pre-incubation of the target neuroblastoma cells with several 5-HT-receptor ligands including 5-hydroxytryptamine, 8-OH-DPAT, ketanserin, 2-methyl-5-HT, as well as a number of potent 5-HT3 agonists and antagonists and two selective neurotoxins, failed to abolish the KCB action of ondansetron. A preliminary structure-activity relationship analysis indicates that the KCB activity of ondansetron is almost entirely attributable to its structural nucleus, 2,3-dihyro-9-methyl-4(lH)-carbazolone. It is hypothesized that the KCB action of ondansetron is mediated through receptors other than 5-HT3 receptors. The KCB activity of ondansetron may be a significant factor in the in-vivo cognition-enhancing activities of this compound, conceivably due to depolarization of the hippocampal synaptic membranes and a consequent augmentation of neurotransmission. 相似文献