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41.
Primary cardiac tumors are uncommon with an estimated incidence of between 0.0017 % and 0.19 %. Most are benign. Whereas myxomas are the most common primary tumor in adults, in children they are exceptionally rare. Cardiac myxomas usually develop in the left atrium, 20 % occur in the right atrium and the remainder develops in the ventricles and rarely in the heart valves. Cerebrovascular strokes secondary to myxoma are rare in childhood. The diagnostic test of choice is transesophageal echocardiogram and early excision is the most effective treatment in preventing serious complications. We report a case of cerebral stroke as the only manifestation of an atrial myxoma in an 11-year-old-girl. The patient presented vertigo, right hemiparesis of the body and dysarthria without loss of consciousness. After diagnostic tests (computerized tomography, magnetic resonance imaging and cerebral angioresonance) she was diagnosed with an ischemic lesion in the left middle cerebral artery. Various investigations were performed to find the cause of the stroke, among them cardiologic study, and a mass in the left atrium suggestive of myxoma was found. The tumor was removed and the diagnosis of myxoma was confirmed by histopathological examination. Outcome was satisfactory. The presence of a cerebral ischemic episode, with or without concomitant heart disease, suggests the need to look for cardiac etiology.  相似文献   
42.
BACKGROUND: There is controversy about the potential risk of sustained high concentrations of cholesterol and triglyceride in patients with cholestatic chronic liver disease. However, it is currently accepted that cholesterol-lowering therapy may reduce morbidity and mortality rates in hypercholesterolemic patients without preexisting coronary heart disease, as well as in those with coronary heart disease. The objective of this study was to evaluate the effect of cholestyramine on the serum lipid profile of a group of children with Alagille syndrome and hypercholesterolemia. METHODS: Five children with Alagille syndrome and basal serum cholesterol concentrations greater than 230 mg/dL were included. Total serum cholesterol, triglyceride, low-density, and high-density lipoprotein cholesterol concentrations were measured on days 0, 10, 20, and 30 after the administration of oral cholestyramine 100, 250, and 500 mg(kg.d), respectively. Lipid fractions were reported as mean +/- 1 SD. Statistical analysis was performed with Friedman analysis of variance. RESULTS: The basal values and those of the three 10-day subsequent 100-, 250-, and 500-mg(kg.d) cholestyramine periods were as follows: total cholesterol: 327.6 +/- 77.1, 305.4 +/- 52.1, 290.6 +/- 24.1, and 320.6 +/- 32.3, respectively (P = 0.668); triglyceride: 136.4 +/- 14.6, 144.8 +/- 41.3, 161 +/- 30.9, and 165.4 +/- 40.7, respectively (P = 0.356); low-density lipoprotein cholesterol: 245.4 +/- 57.8, 239.8 +/- 48.6, 242.2 +/- 68.6, and 246.4 +/- 49.5, respectively (P = 0.782); and high-density lipoprotein cholesterol: 44.4 +/- 11.2, 41.8 +/- 12.8, 44.6.2 +/- 13.2, and 47 +/- 8.5, respectively (P = 0.431). CONCLUSION: Under the conditions of the current study, no significant effect of variable doses of cholestyramine could be demonstrated on the serum lipid profile of a series of children with Alagille syndrome. While the controversy on the potential atherogenic risk of low-density lipoprotein hypercholesterolemia in patients with chronic liver disease persists, new, prospective pharmacologic or nutritional trials are required.  相似文献   
43.
PURPOSE: To estimate the value of neuropsychological measurements in determining the side of seizure onset for presurgical assessment in patients with temporal lobe epilepsy. The lateralising value of neuropsychological protocols was evaluated for all patients and in subpopulations depending on surgical outcome with regard to seizure control, speech dominance, neuropathology, and need for intracranial EEG recordings. METHODS: A battery of neuropsychological procedures was carried out preoperatively in 125 patients who underwent left (n = 66) or right (n = 59) temporal lobectomies. Binary logistic regression analysis was performed to find sets of variables that allowed the best prediction of the side of seizure onset (assumed to be the operated-on side). RESULTS: Combinations of noninvasive neuropsychological tests and Wada subscores showed the highest lateralising values: 80.8% for all patients, 79.4% in seizure-free patients, 86.0% in patients not rendered seizure free, 85.7% in left speech patients, 77.8% in non-left speech patients, 89.3% in patients with mesial temporal sclerosis (MTS), 78.1% in non-MTS patients, 80.3% in patients who underwent intracranial EEG recordings, and 77.3% in those who did not. CONCLUSIONS: The lateralising value (80-90%) of neuropsychological protocols appears similar to that of other tests widely accepted for lateralisation (ictal and interictal scalp EEG and neuroimaging). Attention should be paid to neuropsychological results, particularly from the Wada test, during presurgical assessment of temporal lobe epilepsy, as they can provide strong support for findings from other lateralising tests, particularly in patients with presumed MTS or in left-speech patients.  相似文献   
44.
Serotonin 5-HT(1A) receptors were characterized in rat resting lymphocytes obtained by cardiac puncture with the use of the ligand [3H]8-hydroxy-2-(di-n-propylamino)tetralin. Selectivity of the specific binding was demonstrated by inhibition experiments with various serotonergic and nonserotonergic drugs. The rank order of potency for inhibition was WAY-100478>pindobind>NAN-190>buspirone>imipramine>serotonin. While pimozide, desipramine, nomifensine, haloperidol and sulpiride did not inhibit the binding. Kinetic parameters calculated from saturation experiments indicated one site of interaction, with an equilibrium dissociation constant of 2.50 nM and maximum binding capacity of 487.21 nmol/10(6) cells. Complete dissociation was obtained with serotonin as the displacement agent, and equilibrium dissociation constant calculated by association and dissociation experiments was 2.03 nM. Thus, serotonin 5-HT(1A) receptors are present in resting lymphocytes. The in vivo administration of the mitogens lipopolysacharide (0.1 mg/kg, 18 h) or concanavalin A (0.2 mg/kg, 18 h) increased the number of sites. The elevation produced by the latter was of higher magnitude than that of lipopolysacharide, and two sites of the binding were determined by isotopic dilution. Immobilization stress (1 h daily for 7 days) also resulted in a significant increase of binding capacity, but was smaller than that produced by the mitogens. The affinity of binding was not affect by the treatments. The results indicate that serotonin 5-HT(1A) receptors are modulated by unspecific and specific immune system activation, as well as by a potent stress condition, which might result in relevant functional modifications in the response of rat lymphocytes.  相似文献   
45.
Although medical literature places great emphasis on therapy, diagnosis remains an essential part of medical practice. We present four clinical cases that show the interaction between pre-test probabilities and the accuracy of investigations (sensitivity, specificity, predictive values and likelihood ratios) The first example studies the influence of meningeal signs in the diagnosis of meningitis. The second one analyzes the diagnostic utility of investigations in patients suspected of dementia. The third example examines the change in the probability of carpal tunnel syndrome depending on the physical examination and the electrodiagnostic studies. The last example explains the use of ROC curves in the diagnosis of demyelinating disease with CSF-IgG index.  相似文献   
46.
PURPOSE: To report a case of cherubism with extensive, bilateral orbital involvement occurring in a 27-year-old woman who had the diagnosis established at the age of 4 years. DESIGN: Single interventional case report. INTERVENTION: Ophthalmologic examination and computed tomography were performed. The patient underwent multiple surgical excisions using a bicoronal and transorbital approach. The excised orbital tissues were studied histopathologically. RESULTS: Computed tomography showed bilateral inferior lateral masses involving the orbital floors and producing marked superior displacement of the orbital contents. The intrinsic expansile bone lesions involved the inferior and lateral orbital walls with apical compression of the optic nerves. Histopathologic examination of the masses revealed scattered giant cells in a fibroblastic stroma containing small vascular channels. The lesion was interpreted as giant cell reparative granuloma. CONCLUSIONS: Giant cell reparative granuloma is an uncommon bone lesion that might involve the orbit. Cherubism should be included in the differential diagnosis of lesions that show the histopathologic features of giant cell reparative granuloma.  相似文献   
47.
PURPOSE: To evaluate the ultrasonographic (US) findings in patients with a referring diagnosis of tennis leg and to explore the relative importance of the plantaris tendon and gastrocnemius muscle in the pathogenesis of this condition. MATERIALS AND METHODS: A cadaveric study was performed to outline the normal anatomy of the posterosuperficial compartment of the calf. Magnetic resonance (MR) imaging and US were performed, followed by gross anatomic correlation. US findings in 141 patients referred with a clinical diagnosis of tennis leg were retrospectively reviewed by means of consensus of two radiologists. Images were analyzed with respect to the integrity of the lower-leg musculotendinous units, presence of fluid collection, and deep venous thrombosis. RESULTS: MR imaging and US enabled distinction of the musculotendinous unit of the plantaris from the remaining muscles of the lower extremity in cadaveric specimens. US findings in the 141 patients included rupture of the medial head of the gastrocnemius muscle in 94 patients (66.7%), fluid collection between the aponeuroses of the medial gastrocnemius and soleus muscles without muscle rupture in 30 patients (21.3%), rupture of the plantaris tendon in two patients (1.4%), and partial rupture of the soleus muscle in one patient (0.7%). Deep venous thrombosis was seen in isolation in 14 patients (9.9%). CONCLUSION: In patients with clinical findings of tennis leg who undergo US, abnormalities of the medial gastrocnemius muscle appear to be more common than those of the plantaris tendon.  相似文献   
48.
49.
OBJECTIVES: To investigate whether patients admitted to the postanesthesia recovery unit (PRU) need routine oxygen supplementation in the immediate postoperative period, by measuring changes in arterial oxygen saturation (SpO2) with a pulse oximeter. MATERIAL AND METHODS: Two hundred ninety-nine patients were admitted to the PRU after surgery. All breathed room air after their operations. During transfer to and time in the PRU, SpO2 was recorded. We administered oxygen through a face mask to patients whose SpO2 fell below 94% and to patients whose SpO2 levels fell below baseline, when baseline values were less than 94%. We recorded patient data, physical status (ASA), type of anesthesia, duration of surgery, Aldrete score upon admission to the PRU and SpO2 before and after surgery while the patient breathed room air. RESULTS: General anesthesia was used in 82.3% of the patients and local-regional anesthesia with sedation in 17.7%. PRU stay was 75.6 +/- 92.4 min. Twenty-five percent of the patients were treated with oxygen after surgery and 75% did not require supplemental oxygen. Time until the appearance of desaturation was 3.3 +/- 2.8 min. The coefficient of multiple correlation between postoperative SpO2 while breathing room air (dependent variable) and preoperative SpO2, age and duration of surgery was R = 0.522 (p < 0.001). CONCLUSIONS: Our results are sufficient to demonstrate the validity of pulse oximetry for avoiding indiscriminate oxygen supplementation in patients admitted to the PRU.  相似文献   
50.
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