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21.
A 5-year-old girl presented with a 1-year history of a subcutaneous swelling in the right parietal region. There were no cerebral symptoms or signs. Plain X-ray of the skull showed a lytic bony lesion with sclerotic margin. Computed tomography showed a hypodense, osteolytic lesion with thinned and bulged inner and outer skull tables with intact continuity. There was no intracranial lesion. At operation, the mass was found to be pink and granular, and was totally enucleated. Histology revealed it to be a benign osteoblastoma.  相似文献   
22.
Naltrexone (NTX) is a potent opioid antagonist used in the treatment of alcohol dependence and heroin abuse. Compared with naloxone, NTX has a longer duration of action largely attributed to its major active metabolite, 6-beta-naltrexol. The purpose of this study was to increase the delivery of 6-beta-naltrexol across human skin in vitro via a novel codrug. A carbonate codrug of 6-beta-naltrexol linked to hydroxybupropion was synthesized and evaluated. In vitro human skin permeation rates were measured using a flow-through diffusion cell system. The drug melting points, solubilities, chemical stability, and skin disposition were determined. The carbonate codrug was hydrolyzed on passing through skin and appeared as a combination of intact codrug and parent drugs, 6-beta-naltrexol and hydroxybupropion, in the receiver solution. The codrug provided a significantly (p<0.05) higher 6-beta-naltrexol flux across human skin than 6-beta-naltrexol base. The extent of parent drug regeneration in the skin ranged from 56 to 86%. A higher stratum corneum partition coefficient and rapid bioconversion of the carbonate codrug in the skin correlated with increased 6-beta-naltrexol delivery rates.  相似文献   
23.
OBJECTIVE: To compare structural and functional outcomes and efficiency of diode laser photocoagulation for retinopathy of prematurity (ROP) when delivered in a pulsed mode versus a near-continuous mode. METHODS: A retrospective study was conducted of 138 patients who underwent diode laser photocoagulation for threshold ROP using either pulsed or near-continuous delivery. Laser-related complications and structural and functional outcomes were analyzed. Prospectively, time efficiency and total energy used were evaluated in nine infants with bilateral symmetric high-risk prethreshold ROP in which one eye of each infant was randomized to pulsed and the fellow eye to near-continuous delivery. RESULTS: There was no significant difference between groups with regards to prevalence of posterior disease (Zone 1 or posterior Zone 2) (p = 0.11), postoperative vitreous haze (p = 0.60), postoperative complications (p = 0.38), retinal detachment (p = 0.90), strabismus (p = 0.73), amblyopia (p = 0.69), or refractive error (p = 0.95). Mean time for treatment was 23 minutes using pulsed delivery versus 14 minutes per eye with near-continuous delivery (p < 0.001). The mean total power used per eye with pulsed mode delivery was 1.5 x 10(5) W versus 1.1 x 10(5) W with near-continuous delivery (p = 0.015). CONCLUSIONS: No differences in complications, functional outcome, or structural outcome were found between using pulsed mode and near-continuous mode diode laser delivery for high-risk ROP. Near-continuous laser delivery, in our hands, was more time-efficient and used less total power.  相似文献   
24.
We hypothesized that increased ambient concentrations of metals, as a consequence of escalating urbanization and industrialization of the Gulf region will respond in increased contamination of edible fish species. In this study, we report concentrations of chromium, manganese, cobalt, copper, zinc, arsenic, cadmium, mercury and lead in meat and liver of wild Red-spot emperor (Lethrinus lentjan) from three sampling points at the UAE coast. Analysis was performed by the ICP-MS/microwave digestion. Our study has shown that meat and liver metal content was significantly higher in areas with higher industrial activity, although metal values did not exceed permitted levels of fish for human consumption.  相似文献   
25.
Comparison of right colon, left colon, and rectal carcinoma   总被引:3,自引:0,他引:3  
Three hundred fifteen cases of adenocarcinoma were analyzed for differences between lesions in the right colon, left colon, and rectum for the period 1978 to 1983. The right colon cancers accounted for 1/3 of the cases and were associated with a higher incidence of anemia. The incidence of obstruction was the same between the right and left colon but lower for the rectal lesions. Left colon and rectal cancers had a higher incidence of gross bleeding than right colon cancers, but all had a high rate of occult blood in the stool. The Duke stage of the lesions, which was similar throughout the colon and rectum, is a reliable prognostic indicator.  相似文献   
26.
Chronic nasal obstruction in children is a very common disorder. Obstructing adenoid is usually the first to blame. Though the clinical assessment is essential, it is often considered unreliable or insufficient. We conducted a prospective clinical study to validate a clinical score predicting the severity of adenoid obstruction in symptomatic children. The clinical score (CS) included mouth breathing, snoring, restless sleep, frequent waking-up at night and obstructive breathing during sleep. Each item received a score of 0 or 1. The palatal airway was evaluated on a lateral nasopharyngeal x-ray. The degree of obstruction was assessed intra-operatively by a laryngeal mirror using a 3-grade scale. The volume of each adenoid specimen was measured. Eighty-six patients were enrolled, 51 boys and 35 girls, aged 13–181 months (mean 52, median 45). The CS correlated very well with the intra-operative findings (p < 0.01) and with the degree of palatal airway obstruction (p < 0.05) but not with the volume of the adenoid removed (p > 0.05). The CS was higher in children younger than 3 years (CS > 3 in 85.7% vs. 29.2%), having more frequent obstructive breathing during sleep (71.43% vs. 21.54%). A CS of three or higher, predicted severe obstruction in 96.5% of patients, as detected intra-operatively. The suggested CS is simple to use and is highly reliable in identifying children in need for adenoidectomy, in the context of normal anterior rhinoscopy and tonsils less than grade three.This work was presented at the podium of the XVIII IFOS in Rome, Italy on June 26, 2005.  相似文献   
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BACKGROUND: The effect of mitral valve morphology (MVM) on the long-term results of mitral balloon valvuloplasty (MBV) is not well established. The aim of the study was to evaluate the impact of MVM on long-term outcome of MBV. METHODS: Five hundred and eighteen consecutive patients (mean age, 31+/-11 years) who underwent successful MBV were followed up for 0.5-16.5 (mean, 6+/-4.5) years. Patients were divided into two groups according to their mitral echo score (MES) before MBV: group A (n=340; MES8). RESULTS: We report the immediate and long-term clinical and echocardiographic results of the above-mentioned 518 consecutive patients. The mitral valve area was significantly larger in group A than in group B, both immediately after MBV (2.0+/-0.3 vs. 1.82+/-0.3 cm2, respectively; P<0.0001) and also at the last follow-up (1.8+/-0.33 vs. 1.5+/-0.33 cm2, respectively; P<0.0001). Restenosis occurred in 38/340 (11%) in group A vs. 73/178 (41%) in group B (P<0.0001). Actuarial freedom from restenosis at 5, 10, 15 years were 92+/-2%, 85+/-3%, 65+/-6% for group A vs. 72+/-4%, 44+/-5%, 9+/-6% for group B (P<0.001). Event-free survival rates at 5, 10, 15 years for group A were 93+/-1%, 88+/-2%, 66+/-6% vs. 82+/-3%, 59+/-6%, 8+/-7% for group B (P<0.0001). Stepwise Cox multivariate regression analysis identified MES, preprocedure functional class, and postprocedure mitral valve area相似文献   
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