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PurposeTo evaluate feasibility, safety, and results of endovenous mechanochemical ablation (MOCA) for treatment of persistent embryonic and dysplastic veins in pediatric patients with Klippel-Trénaunay syndrome (KTS).Materials and MethodsThirteen MOCA procedures were performed in 11 patients (age range, 4–16 years) with KTS and symptomatic persistent embryonic or dysplastic veins during a 24-month period. All patients were evaluated with color Doppler (CD) ultrasound (US), contrast-enhanced MR imaging, and venography to assess the anatomy of the target vessels and patency of the deep venous system. All procedures were performed under general anesthesia with a ClariVein catheter and liquid sodium tetradecyl sulfate as the sclerosing agent. US and fluoroscopic guidance were used in all cases. Technical success rate, primary occlusion rate, adverse effects, and recanalization rates were evaluated. Clinical and radiological (CD US) controls were performed 1 day, 7 days, 1 month, and 6 months after the procedure and once a year thereafter, with a mean follow-up of 16 months (range, 6–25 months).ResultsTechnical success and primary occlusion were achieved in all patients with no adverse events. During the follow-up period, CD US demonstrated partial recanalization and symptom recurrence in 2 patients (18%), 14 and 18 months after the initial procedure. These 2 patients had a second ablation procedure with no recanalization or symptom recurrence during the subsequent follow-up period.ConclusionsMOCA is feasible and appears to be a safe and effective technique for treatment of varicose veins in pediatric patients with KTS.  相似文献   
3.
Several methods (e.g. tensile strength, shear bond strength) have been used in testing metal-ceramic bonds. However, in the interface, structural and analytical investigations can be applied in determining the chemical and phase structure of substances making up the bond. The aim of the present study is to assess the interface between Wiron 99 (Bego) alloy and Vision (Wohlwend) VITA VMK68 (Vita), Carat (Dentsply/DeTrey) ceramic using transmission electron microscopy (TEM) and 3-point bending test. In the case of NiCr alloys, morphologically similar but structurally varying phases developed in all of the ceramics. In each case, a Cr2O3 layer consisting of small crystals (10-20 nm) was noticed with a series of underlying bubble-like amorphous inclusions. The exact three dimensional (3D) location of these structures and their relation to the glass-phase of the ceramic, as well as its role in the nanomechanical anchoring of the ceramic are still to be clarified. The values of debonding stress were 41.67 +/- 5.01 MPa, 52.89 +/- 8.06 MPa and 56.58 +/- 10.21 MPa for Carat, VITA VMK68 ceramic and Vision, respectively. These parameters do not present significant difference at p > or = 0.05 among the three types of ceramics. Based on our measurements it is highly likely that the micromorphology of interface is basically determined by the composition of the alloy while in the chemical composition of the newly developed phases the ceramic and the parameters of firing (temperature, magnitude of vacuum and firing time) play an important role. Values of cracking and morphological resemblance suggest that the superficial micromorphological and nanomorphological structures, acting as mechanical anchoring elements, play an important role in fixing the ceramic.  相似文献   
4.
The aim of this study was to develop an in vitro model in which the pressure in the periapical tissues can be measured during loading. Extracted human maxillary central incisors were embedded into resin blocks that had physical characteristics similar to bone and periodontal ligament. Each tooth was loaded with 20, 40, 50, 60, 75, 85, 100, 200, 300 and 450 N vertical forces from the incisal edge of the crown; this procedure was carried out three consecutive times. A minute resistor embedded in the periapical space was used to detect apical pressure changes during occlusal loading. The ratio of apical pressure changes (delta P) to the loading force changes (delta F) was calculated. The periapical pressure detected was in direct proportion to the loading force. The mean value of delta P/delta F was 5.994 kPa/N (SD = 2.04). Direct proportionality was found between the coronal loading and the apical hydrostatic pressure. The (delta P)/(delta F) ratio determined in this study makes it easier to estimate the apical hydrostatic pressure values during occlusal loading of single rooted teeth. In this study the apical pressure generated under occlusal loading was of the same magnitude as that estimated with the finite element method.  相似文献   
5.
To compare the clinical features, visual outcomes and causative organisms between endophthalmitis secondary to cataract surgery or to intravitreal injections (IVI). Meir Medical Center, Kfar Saba, Israel. Retrospective, non-randomized comparative chart review. Medical records of patients with proven or suspected endophthalmitis admitted to the Ophthalmology Department at Meir Medical Center 2/2002–2/2017 were reviewed. Clinical characteristics including presenting and final visual acuity (VA) outcomes, causative organisms and time to admission were assessed. Among 84 patients in our study, 35 had preceding cataract surgery and 12 had preceding IVI. The post-cataract group showed a significant improvement in VA following treatment with a presenting and final VA (logMar ± SD) of (1.80 ± 0.54 and 1.39 ± 0.65, P < 0.01) as opposed to the post-IVI group (1.72 ± 0.26 and 1.81 ± 0.32, P = 0.692), while most patients in the cataract group exhibited some degree of VA recovery (70.96%). Patients undergoing cataract surgery were divided into two separate groups; those who underwent cataract surgery in a private center and those operated at a public center. Patients undergoing surgery at a private medical center showed improvement in VA outcomes following treatment (1.80 ± 0.57 and 1.13 ± 0.66, P < 0.01) as opposed to those operated on at our public medical center. Overall, patients with endophthalmitis following cataract surgery had better visual outcomes and were more likely to show a VA improvement following treatment when compared with endophthalmitis following IVI. Final VA outcomes of patients with endophthalmitis after cataract surgery performed in a private center were better than those operated on and treated in a public medical center.  相似文献   
6.
The increased survival rate of stroke patients has led to the higher incidences of post‐stroke depression. Carnosic acid has the ability to cross blood brain barrier with good neuro‐modulatory actions. Recently, inclined level of fibroblast growth factor 9 (FGF9) in the postmortem brain of the depressed patients was noted. Therefore, in the present study, the effect of carnosic acid on post‐stroke depression‐like behavior, and the expression of FGF9 were evaluated. After 3 weeks of middle carotid artery occlusion in Sprague Dawley rats, carnosic acid (20 and 40 mg/kg) was administered for 2 weeks. Sucrose preference test, forced swimming test, and open field test were performed and hippocampi were analyzed for FGF9 and FGFR‐3. In comparison to post‐stroke depressed rats, carnosic acid increased the sucrose preference, and reduced the immobility time of the rats by ~2×. The speed and distance‐covered were also increased. At 40 mg/kg, FGF9 was reduced by ~3× while FGFR‐3/Actin was increased by ~1.5×. Altogether results suggest anti‐depressant‐like activity of carnosic acid in post‐stroke depressed rats with decreased expression of hippocampal FGF9.  相似文献   
7.

Background

Traffic accidents are considered a public health problem and, according to the World Health Organization, currently is the eighth cause of death in the world. Specifically, pedestrians, cyclists and motorcyclists contribute half of the fatalities. Adequate clinical management in accordance with aggregation patterns of the body areas involved, as well as the characteristics of the accident, will help to reduce mortality and disability in this population.

Methods

Secondary data analysis of a cohort of patients involved in traffic accidents and admitted to the emergency room (ER) of a high complexity hospital in Medellín, Colombia. They were over 15 years of age, had two or more injuries in different areas of the body and had a hospital stay of more than 24 h after admission. A cluster analysis was performed, using Ward's method and the linfinity similarity measure, to obtain clusters of body areas most commonly affected depending on the type of vehicle and the type of victim.

Results

Among 2445 patients with traffic accidents, 34% (n = 836) were admitted into the Intensive Care Unit (ICU) and the overall hospital mortality rate was 8% (n = 201). More than 50% of the patients were motorcycle riders but mortality was higher in pedestrian-car accidents (16%, n = 34). The clusters show efficient performance to separate the population depending on the severity of their injuries. Pedestrians had the highest mortality after having accidents with cars and they also had the highest number of body parts clustered, mainly on head and abdomen areas.

Conclusions

Exploring the cluster patterns of injuries and body areas affected in traffic accidents allow to establish anatomical groups defined by the type of accident and the type of vehicle. This classification system will accelerate and prioritize ER-care for these population groups, helping to provide better health care services and to rationalize available resources.  相似文献   
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9.
Pazopanib, an oral inhibitor of vascular endothelial growth factor receptor, platelet-derived growth factor receptor, and c-kit kinases, inhibits multiple cytochrome P450 (CYP450) enzymes in vitro. This study in patients with advanced cancer evaluated the effect of pazopanib on CYP450 function by comparing the pharmacokinetics of CYP-specific probe drugs in the presence and absence of pazopanib. The probes used included midazolam (CYP3A specific), warfarin (CYP2C9 specific), omeprazole (CYP2C19 specific), caffeine (CYP1A2 specific), and dextromethorphan (CYP2D6 specific). The estimated ratios of the geometric means (90% confidence interval (CI)) for the area under the curve to the last measurable point (AUC(0-t)) for these probe drugs with/without pazopanib were as follows: midazolam, 1.35 (1.18-1.54); omeprazole, 0.81 (0.59-1.12); caffeine, 1.00 (0.77-1.30); and S-warfarin, 0.93 (0.84-1.03). The geometric least-squares (LS) mean ratio of urine dextromethorphan:dextrorphan ranged from 1.33 (0-4-h interval) to 1.64 (4-8-h interval). The data suggest that pazopanib is a weak inhibitor of CYP3A4 and CYP2D6 and has no effect on CYP1A2, CYP2C9, and CYP2C19 in patients with advanced cancer.  相似文献   
10.
The aim of the study was to evaluate the presence of aromatase cytochrome P450 enzyme (P450AROM) expression in normal pituitary tissues and tumor tissues of patients with prolactinoma and to examine the impact of the P450AROM expression on clinical outcome. Twenty-six consecutive human pituitary tissue samples were obtained from autopsies performed at the Institute of Forensic Medicine. Sixty-four patients who had an adenomectomy between 2000 and 2009 after prolactinoma diagnosis with histologically confirmed pituitary tumor tissues were retrospectively included in this study. The slices from the pituitary tissues were subjected to immunohistochemical staining for evaluation of P450AROM and estrogen receptor beta (ER beta) subunit. Immunohistochemistry results were compared according to age, gender, remission rate, resistance and invasion status of the patients. Higher than normal P450AROM expression was found in the pituitary tissues of the patients with prolactinoma (p < 0.001). P450AROM intensity had no relation to resistance or remission in patients with prolactinoma (p = 0.44, p = 0.45, respectively). The subgroup analysis showed that compared to males without invasive adenoma, males with invasive adenoma had higher P450AROM expression (p = 0.048). ER beta was found to have an impact on resistance (p = 0.049). This study shows that P450AROM expression is present in the pituitary tissues of patients with prolactinoma and that this presence could be important in development and tumor behavior of prolactinomas.  相似文献   
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