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51.
转译神经科学与焦虑障碍   总被引:1,自引:0,他引:1  
在20世纪后期,将精神疾病的基础及临床前研究“转译”(translated)到临床相关概念从而引导临床研究的方法已经成为可能。基础神经科学实验的大量成果、大脑分子生物学研究技术的进步及日益精湛的神经影像技术引进到人类和动物研究使得将转译研究(translationalresearch)用于精神病学具有令人振奋的前景。起初,焦虑障碍因为有能极好地反映恐惧的动物模型以及具有广泛性特征,似乎是转译神经科学在精神障碍中应用的典范。然而,关于恐惧与焦虑之间的关系还存在着大量的争论。许多人认为它们是不同的概念:恐惧是对真实危险的自动反应,而焦虑则为…  相似文献   
52.
53.
SYNOPSIS
Few controlled studies have examined the effectiveness of relaxation therapy for the treatment of adolescent headaches. In this study, ten chronic headache sufferers (migraine or muscle contraction), ranging in age from 12 to 17 years (M = 13.5 SD = 1.3), were sequentially assigned to either a relaxation therapy or waiting-list control group. Following treatment, subjects in the treatment group demonstrated significantly lower Headache Index scores than subjects in the control group (U = 0, p £ .004). Group differences in Headache Free Days, Peak Headache Rating, and Medication Index scores were not significant; differences in Medication Index scores approached significance at U = 3, p £ .03. Objective compliance to treatment data indicated subjects overreported their actual practice time, on average, by 70%. Results and implications for future research are discussed.  相似文献   
54.
Abstract: Scabies in neonates and infants has a clinical pattern that may be easily misdiagnosed. The eruption is generalized, including involvement of the head, neck, face, palms, and soles, with an early tendency to pustule formation. Other lesions include papules, vesicles, and burrows, which may be obliterated by secondary lesions. A confusing clinical picture resulted in a delay in diagnosing scabies in a 23-day-old infant who was successfully treated with permethrin 5% cream.  相似文献   
55.
Study Objective . To determine the appropriate compartmental and noncompartmental pharmacokinetic parameters for intravenous piperacillin and tazobactam. Design . Sequential selection of patients entered into a randomized, open-label clinical efficacy trial. Setting . Los Angeles County-University of Southern California Medical Center. Participants . Sequential sample of 18 patients admitted for intraabdominal infections and consented into a comparative antibiotic trial. Interventions . Patients received piperacillin 4 g plus tazobactam 500 mg by intravenous intermittent infusion every 8 hours. Measurements and Main Results . The estimated noncompartmental pharmacokinetic parameters (mean ± SD) for piperacillin and tazobactam, respectively, were as follows: maximum concentration in plasma 218.7 ± 48.9 μg/ml and 27.8 ± 9.1 μg/ml; half-life 1.07 ± 0.22 hours and 1.00 ± 0.27 hours; elimination rate constant 0.67 ± 0.13 hr−1 and 0.73 ± 0.18 hr−1; area under the concentration-time curve from zero hour to infinity 288.5 ± 71.25 mg·hr/L and 36.3 ± 9.55 mg·hr/L; total plasma clearance 14.75 ± 3.93 L/hour and 14.78 ± 4.39 L/hour; renal clearance 5.69 ± 1.94 L/hour and 7.85 ± 3.37 L/hour; volume of distribution at steady state 21.00 ± 4.18 L and 22.47 ± 8.27 L; and mean residence time 1.72 ± 0.29 hours and 1.79 ± 0.35 hours. Conclusion . Our findings were similar to those in other surgical patient models. The two-compartmental model best described piperacillin and tazobactam disposition in our patients. Bayesian analyses of the two-compartment models of piperacillin and tazobactam were able to predict trough, peak, and 2-hour postadministration levels without bias.  相似文献   
56.
The clinical and computerized tomographic (CT) findings in 10 patients with cerebral toxoplasmosis are reviewed. All patients with cerebral toxoplasmosis were homosexuals and/or intravenous drug users, and all patients had other manifestations of AIDS. Two presented with focal seizures, 4 presented with focal neurological deficit which progressively worsened, and 4 had evidence of diffuse neurological dysfunction (altered consciousness, generalized seizures). CT showed a single lesion in 3 patients and multiple lesions in 7 patients. Two patients had hypodense nonenhancing lesions(s). Eight patients had hypodense lesions with peripheral or nodular enhancement. The lesions were more commonly located in the cerebral hemispheres and subcortical gray matter nuclear masses (thalamus, basal ganglia). The finding of a hypodense lesion with a central slightly hyperdense noncalcified region that showed dense nodular homogeneous enhancement was quite characteristic of cerebral toxoplasmosis, but this pattern may also be seen in other neurological conditions including brain lymphomas.  相似文献   
57.
Fetal diagnosis has vastly improved over the last decade. Ultrasound has become the imaging modality of choice. As real-time equipment has improved technologically, the ability to deduce subtle abnormalities has greatly increased. The fetal genitourinary tract may be evaluated for renal dysplasias, anomalies, or obstruction. Points of obstruction and, at times, the exact cause of obstruction may be deduced. Abnormalities of the ureter, bladder, urethra, scrotum, or reproductive system can be detected.  相似文献   
58.
One-hundred-and-seventy-six patients with potentially operable squamous cell carcinoma or adenocarcinoma of the middle or lower thirds of the oesophagus were randomly assigned to preoperative radiotherapy or surgery alone. Patients assigned to the radiotherapy arm received 20 Gy in 10 treatments over 2 weeks, using parallel opposed 4 MV beams. The preoperative radiotherapy was not associated with any significant acute morbidity or any increase in operative complications. The median survival of the overall group of 176 patients was 8 months, and the 5-year survival was 13%. There was no significant difference in the survival of the 90 patients who received preoperative radiotherapy and the 86 who were managed by surgery alone. Proportional hazards analysis identified lymph node involvement, high tumour grade and male sex as significant adverse prognostic features, but the treatment option assigned had no prognostic significance. It was concluded that low dose preoperative radiotherapy offered no advantage over surgery alone.  相似文献   
59.
Using abdominal ultrasonographic data and laboratory tests, radiologists often find differential diagnoses of hepatic masses difficult. A computerized second opinion would be especially helpful for clinicians in diagnosing liver cancer because of the difficulty of such diagnoses. A back-propagation neural network was designed to diagnose five classifications of hepatic masses: hepatoma, metastic carcinoma, abscess, cavernous hemangioma, and cirrhosis. The network input consisted of 35 numbers per patient case that represented ultrasonographic data and laboratory tests. The network architecture had 35 elements in the input layer, two hidden layers of 35 elements each, and 5 elements in the output layer. After being trained to a learning tolerance of 1%, the network classified hepatic masses correctly in 48 of 64 cases. An accuracy of 75% is higher than the 50% scored by the average radiology resident in training but lower than the 90% scored by the typical board-certified radiologist. When sufficiently sophisticated, a neural network may significantly improve the analysis of hepatic-mass radiographs.  相似文献   
60.
Surgical reinterventions following the Fontan procedure.   总被引:2,自引:0,他引:2  
OBJECTIVE: The Fontan procedure is utilized as a final reconstructive procedure for patients with functional single ventricle. Short- and long-term outcomes have improved significantly, however, some patients require additional cardiac procedures following the Fontan operation. The outcomes for these reinterventions are not known. METHODS: Cardiac Surgery and Cardiac Intensive Care Unit databases at The Children's Hospital of Philadelphia were reviewed to identify all patients who underwent cardiac surgery after a previous Fontan operation between January 1, 1995 and December 31, 2001. RESULTS: During the study period, 123 procedures were performed in 71 patients. The median time from Fontan to reoperation was 3.6 years (range 0.1-20 years). Indications for reintervention included arrhythmia, cyanosis, 'failing' Fontan circulation or exercise intolerance, protein losing enteropathy, atrioventricular valve (AVV) regurgitation, and other indications. Procedures included pacemaker insertion or revision (n = 59, 48%), reinclusion of previously excluded hepatic veins (n = 16, 13%), revision to either a lateral tunnel or extra-cardiac conduit Fontan (n = 13, 11%), cardiac transplantation (n = 9, 7%), enlargement or creation of a baffle fenestration (n = 6, 5%), isolated AVV repair or replacement (n = 2, 2%), and other procedures (n = 18, 14%). There were five early and five late deaths. Hospital mortality was greatest for patients undergoing cardiac transplantation (4/9, 44%), accounting for 80% of the early deaths. CONCLUSIONS: Surgical reinterventions following the Fontan procedure may be necessary for multiple indications which result in impairment of the Fontan circulation. Most reinterventions can be performed with minimal morbidity and mortality. Survival for patients requiring cardiac transplantation following the Fontan procedure remains poor.  相似文献   
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