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21.
Positron emission tomography scans of nine patients diagnosed with summer seasonal affective disorder (SSAD) were compared with scans of 45 normal control subjects to investigate differences in brain glucose metabolism. All subjects performed an auditory discrimination task beginning several minutes before injection of F-18-deoxyglucose and continuing for 30 minutes after injection. Regional glucose metabolic rates were extracted from 60 rectangular regions of interest measured in five planes selected as atlas matches from 28 total slices. Statistically significant differences between patients with SSAD and normal control subjects were found in cerebral glucose metabolic rate and also in normalized regional glucose metabolic rates in the orbital frontal cortex and in the left inferior parietal lobule.  相似文献   
22.
The association is well established between congenital heart disease and spinal deformities such as scoliosis or kyphosis, but data are not available for risks and the outcome of heart surgery in patients with spinal deformities. We report a case of successful orthotopic heart lung transplantation in a patient with complex congenital heart disease and severe chest deformity who had undergone previous spinal fusion surgery for progressive right convex thoracic kyphoscoliosis.  相似文献   
23.
2-Phenylpyrazolo[4,3-c]quinolin-3(5H)-one (CGS 8216) is pharmacologically characterized as benzodiazepine antagonist with low inverse agonistic effects. Single oral doses up to 650 mg and subchronic doses up to 100 mg daily for seven days are well tolerated by young healthy volunteers. Plasma concentrations of CGS 8216 are variable, not dose-related and relatively low considering the doses administered. A high plasma concentration ratio of metabolite vs. parent compound (3:1) points to an extensive gastrointestinal first-pass metabolism. CGS 8216 influences the human electroencephalogram similar to anxiolytic and vigilance enhancing drugs in doses which do not change performance of psychometric tests. CGS 8216 antagonizes the diazepam-induced impairment of alertness.  相似文献   
24.
Summary The protein binding of furosemide was investigated in plasma from 22 old and 11 young subjects by equilibrium dialysis. The unbound fraction of furosemide was 3.16% in plasma from the elderly and 1.71% in plasma from the young. A significant correlation was found between the unbound fraction of furosemide and the plasma concentration of albumin. The average number of binding sites was 3.8 (elderly) and 2.7 (young) 10–6 mol/g albumin. The average association constant (K) was 4.3 (elderly) and 4.2 (young) 105 M–1. By increasing the concentration of furosemide up to 200 µg/ml buffer the unbound fraction of the drug rose to 5.2% (elderly) and 3.5% (young).  相似文献   
25.
26.
Nonparasitic Cysts of the Liver: Results and Options of Surgical Treatment   总被引:5,自引:0,他引:5  
n = 9) should be regarded as a palliative measure. Within a short period, CT-guided aspiration led to recurrence of symptoms in seven of our patients. Standard treatment of NPHC is fenestration with widest possible excision of the cystic wall, which can be performed laparoscopically ( n = 10) or by the conventional surgical mode ( n = 54). One patient was initially operated by the laparoscopic technique but developed bleeding, which necessitated conversion to the open mode. Three patients underwent synchronous laparoscopic cholecystectomy. Recurrence rates were similar: 11% in the laparoscopically treated group and 13% in the group that underwent conventional open surgery. Conventional surgical treatment was always successful in cases of solitary cysts. However, in cases of multiple cysts measuring more than 5 cm, conventional surgery was followed by recurrence of symptoms in 26% of patients (7/27), who then had to undergo a second operation. Partial resection of the liver ( n = 9) was successfully performed in cases of polycystic disease ( n = 5) with concomitant enlargement of the organ as well as in cases of large solitary cysts of the left lobe of the liver ( n = 4). In patients in whom we found that the cysts communicated with the ductal system ( n = 3), we performed a cystojejunostomy to drain the bile. The complication rate was low. In addition to frequent postoperative ascites, which necessitated no further intervention, we observed infectious complications in four patients. Twenty patients (22%) expired during a mean follow-up period of 6.2 years. Interestingly, deaths were frequently associated with malignancy (11/20). After fenestration of multiple cysts measuring > 5 cm, the patients are at high risk for recurrence. Hence partial resection of the liver is an excellent therapeutic alternative in selected patients with polycystic disease and massive enlargement of the organ in whom the disease could not be controlled by simple fenestration. The results of this study show that laparoscopic fenestration should replace the conventional surgical technique as the gold standard in cases of NPHC because the laparoscopic technique is less stressful for the patient and is associated with a rate of success similar to that of the conventional technique.  相似文献   
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28.
This study is comprised of 71 patients with inversion injuries. The purpose of this article is to present a logical and orderly approach in evaluating these injuries. A comprehensive review of the literature concerning diagnostic techniques and mechanisms of injury related to inversion ankle trauma is presented. Inversion ankle injuries are frequently misdiagnosed as simple sprains when frequently there are other pathologies present. The standard approach of evaluating inversion ankle injuries is often inadequate.  相似文献   
29.
Dimensional analysis of animals with regard to those structures and functions which affect the rate of energy metabolism can be conducted on the basis of either geometric or elastic similarity. Predictions of the relationships between various structures and functions and body mass are dependent of the type of similarity assumed. Comparison of the relationships between numerous physiological variables and body mass reported in the literature and those predicted from geometric and elastic similarity indicates that the preponderance of predictions from elastic similarity are in better agreement with the observed values than are the predictions from geometric similarity. It appears that the components of the cardiovascular system are scaled in accordance with elastic similarity. For this reason, cardiac output is proportional to body mass raised to the 3/4 power. The biochemical basis for the relationship between cardiac output and the rate of energy metabolism is discussed.  相似文献   
30.
Although magnetic resonance imaging has a high sensitivity for cerebral and spinal tumors, demonstration of small lesions can be difficult. In a patient with multiple extra- and intraspinal tumors due to neurofibromatosis generalisata, the use of the MRI contrast agent Gadolinium-DTPA resulted in a better differentiation especially of small lesions. High tumor contrast facilitated a safe localisation of the widespread disease using a fast imaging sequence (FLASH).  相似文献   
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