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91.
BACKGROUND: The dopamine transporter (DAT) is known to be a key regulator of dopamine, and recent studies of genetics, treatment, and imaging have highlighted the role of DAT in attention-deficit/hyperactivity disorder (ADHD). The findings of in vivo neuroimaging of DAT in ADHD have been somewhat discrepant, however. METHOD: Dopamine transporter binding was measured using a highly selective ligand (C-11 altropane) and positron emission tomography (PET). The sample consisted of 47 well-characterized, treatment-na?ve, nonsmoking, non-comorbid adults with and without ADHD. Additionally, control subjects had few symptoms of ADHD. RESULTS: Results showed significantly increased DAT binding in the right caudate in adults with ADHD compared with matched control subjects without this disorder. CONCLUSIONS: These results confirm abnormal DAT binding in the striatum of adults with ADHD and provide further support that dysregulation of DAT may be an important component of the pathophysiology of ADHD.  相似文献   
92.
BACKGROUND: Brachial artery reactivity (BAR), carotid intima-media thickness (IMT), and applanation tonometry for evaluation of total arterial compliance may provide information about preclinical vascular disease. We sought to determine whether these tests could be used to identify patients with coronary artery disease (CAD) without being influenced by their ability to identify those at risk for CAD developing. METHODS: We studied 100 patients and compared 3 groups: 35 patients with known CAD; 34 patients with symptoms and risk factors but no CAD identified by stress echocardiography (risk group); and 31 control subjects. BAR and IMT were measured using standard methods, and total arterial compliance was calculated by the pulse-pressure method from simultaneous radial applanation tonometry and pulsed wave Doppler of the left ventricular outflow. Ischemia was identified as a new or worsening wall-motion abnormality induced by stress. RESULTS: In a comparison between the control subjects and patients either at risk for developing CAD or with CAD, the predictors of risk for CAD were: age (P =.01); smoking history (P =.002); hypercholesterolemia (P =.002); and hypertension (P =.004) (model R = 0.82; P =.0001). The independent predictors of CAD were: IMT (P =.001); BAR (P =.04); sex (P =.005); and hypertension (P =.005) (model R = 0.80; P =.0001). CONCLUSION: IMT, BAR, and traditional cardiovascular risk factors appear to identify patients at risk for CAD developing. However, only IMT was significantly different between patients at risk for developing CAD and those with overt CAD.  相似文献   
93.
94.
Stent fracture is uncommon but may have consequences including restenosis. To date, stent fractures reported have been related to aggressive post dilation. We describe a case that involves fracture of a stent deployed to nominal pressure. Unlike most stent fractures reported that involve stent struts only our case demonstrated circumferential disruption with complete separation of the stent segments.  相似文献   
95.
The induction of a granulomatous inflammation by jellyfish toxins is rare. More typically, acute toxic and urticarial reactions are seen. An 11-year-old boy developed a striated urticarial erythema on the left cheek after contact with a gelatinous mass while swimming in the sea in Croatia. After initial erosion, a striated induration developed in the area of contact. Histological examination revealed a granulomatous inflammation with some eosinophils. While topical steroid-based antiinflammatory and antibacterial therapy over several weeks was not effective, topical therapy with tacrolimus 0.1% for two two-week treatment periods led to healing of the skin changes with a slight scar. There was no clinical recurrence after 5 month of follow-up.  相似文献   
96.
OBJECTIVE: The purpose of this study was to evaluate the potential benefit of an ultrasonic device in apical surgery on the outcome of treatment. STUDY DESIGN: A randomized prospective design was used in a standardized treatment protocol. Patients were allocated to treatment with an ultrasonic device (P-Max Newtron) or treatment with a bur in an otherwise similar protocol. One year after treatment the results were evaluated by 2 oral and maxillofacial surgeons who were blinded for the therapy. RESULTS: Out of a total group of 399 patients who were included in the study, adequate follow-up could be obtained in 290 patients. The overall success rate in the ultrasonic group was 80.5% and in the group treated with a bur 70.9% (P = .056). In molars, the difference in success rate was significant (P = .02). CONCLUSION: The use of an ultrasonic device in apical surgery improved the outcome of treatment. In molars this effect was significant.  相似文献   
97.
BACKGROUND CONTEXT: The effectiveness of spinal surgery as a treatment option is currently evaluated through the assessment of patient-reported outcomes (PROs). The minimum clinically important difference (MCID) represents the smallest improvement considered worthwhile by a patient. The concept of an MCID is offered as the new standard for determining effectiveness of a given treatment and describing patient satisfaction in reference to that treatment. PURPOSE: Our goal is to review the various definitions of MCID and the methods available to determine MCID. STUDY DESIGN: The primary means of determining the MCID for a specific treatment are divided into anchor-based and distribution-based methods. Each method is further subdivided and examined in detail. METHODS: The overall limitations of the MCID concept are first identified. The basic assumptions, statistical biases, and shortcomings of each method are examined in detail. RESULTS: Each method of determining the MCID has specific shortcomings. Three general limitations in the accurate determination of an MCID have been identified: the multiplicity of MCID determinations, the loss of the patient's perspective, and the relationship between pretreatment baseline and posttreatment change scores. CONCLUSIONS: An ideal means of determining the MCID for a given intervention is yet to be determined. It is possible to develop a useful method provided that the assumptions and methodology are initially declared. Our efforts toward the establishment of a MCID will rely on the establishment of specific external criteria based on the symptoms of the patient and treatment intervention being evaluated.  相似文献   
98.
Direct vascular injury after primary total knee arthroplasty is rare. This case report illustrates a 65-year-old female who was diagnosed with a pseudoaneurysm of the popliteal artery when she was investigated for increased leg swelling and pain 1 week after total knee arthroplasty. She had a percutaneous endovascular repair with a stent after thrombectomy.  相似文献   
99.
This study examined the structure and symptom correlates of perfectionism in a sample of 6th-grade, urban, African American children using the Child and Adolescent Perfectionism Scale (CAPS; Flett, Hewitt, Boucher, Davidson, & Munro, 2000). Confirmatory factor analysis showed inadequate fit of the original subscales. Exploratory factor analysis suggested 3 dimensions of perfectionism: A Socially Prescribed and a Self-Oriented-Critical factor were described as maladaptive, whereas a Self-Oriented-Striving factor was proposed as adaptive. Cross-sectional correlations among the perfectionism dimensions and symptoms of psychopathology fit well with the adaptive versus maladaptive model. In addition, Socially Prescribed Perfectionism showed a robust predictive relation to 7th-grade internalizing symptoms, especially depression, in boys. Results are discussed in the context of the cultural and socioeconomic characteristics of this African American sample and suggestions for future research are provided.  相似文献   
100.
PURPOSE: To evaluate prospectively the safety and efficacy of totally percutaneous placement of abdominal and thoracic aortic endografts using the Prostar XL suture-mediated closure system. METHODS: From January 2002 to January 2005, we attempted to insert percutaneously all bifurcated abdominal aortic and thoracic endografts. Consecutive patients (25 men, four women), with mean age 74.9 years (range 44-84), underwent endovascular repair for 20 abdominal aortic aneurysms (AAA) and nine thoracic aortic aneurysms (repeat operation in one case). Endografts used included 21 Zenith (Cook), eight Talent (Medtronic), one AneuRx (Medtronic). For the technique, two Prostar XL 8F were used to close 22-24F access sites and one Prostar XL 10F to close 16F access sites. RESULTS: Procedural success was achieved in 21/29 (72.4%) patients and in 39/47 access sites (83%). Closure of 22-24F access sites with tandem 8F Prostar devices was successful in 23/29 (79.3%) cases. Closure of 16F access sites with 10F Prostar device was successful in 16/18 (88.8%) cases. There were seven peri-procedural failures requiring surgery to repair the femoral artery in three cases. Four access complications healed without intervention. Overall 25/29 (86.2%) patients had complete percutaneous repair. No late complications were detected during follow-up (median 17.5 months). CONCLUSIONS: Percutaneous treatment of patients with AAA and thoracic aneurysms is feasible in most cases, with a very low risk of access-related complication, providing that the operator has sufficient practical experience of this technique.  相似文献   
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