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991.
Multislice proton MR spectroscopic images (SI) of the brain were quantitated, using the phantom replacement technique. In 16 normal volunteers, ranging in age from 5 to 74 years, average “whole brain” concentrations of choline (Cho), creatine (Cr), and N-acetylaspartate (NAA) were found to be 2.4 ± 0.4, 7.9 ± 1.3, and 11.8 ± 1.0 (mM, mean ± SD), respectively. These values are in good general agreement with those previously determined by single-voxel localization techniques. Cortical gray matter was found to have lower Cho and NAA levels, compared to those of white matter, corpus callosum, and basal ganglia. Cho was also found to increase significantly with age in several locations. Quantitative multislice proton SI is feasible in the clinical environment, and regional and age-dependent variations occur that must be accounted for when evaluating spectra from pathological conditions.  相似文献   
992.
A double or bilobar gallbladder is a rare congenital anomaly. If not recognized during preoperative evaluation or operation, it can cause severe complications. We describe two cases in which a second operation had to be performed because of the presence of a second or bilobar gallbladder that was not recognized in the preoperative evaluation and during (laparoscopic) cholecystectomy. The types of anomalies, the concomitant pathology, and treatment are discussed.  相似文献   
993.
994.
We report the results of a prospective and randomized trial designed to study the incidence of abdominal and pulmonary complications in gallstone surgery comparing subcostal (SI) with midline incision. The need for postoperative analgesia was lower in the SI group. There was no difference in the degree of hypoxaemia in the first two postoperative days, but there was less impairment of pulmonary function in terms of vital capacity and forced expiratory volume in 1 s (P less than 0.0001) in the SI group. SI patients also had a lower incidence of pulmonary or abdominal complications but the difference was not significant. Finally, we found a reduced hospital stay for the SI patients (P less than 0.01), probably related to a reduced postoperative analgesic requirement and an improved pulmonary function. We conclude that subcostal incision is a better approach for biliary tract surgery and should be used whenever possible.  相似文献   
995.
996.
Disturbances in the metabolism of purines and pyrimidines in neurologically affected patients can be reflected by aberrant concentrations of nucleosides and nucleobases in cerebrospinal fluid (CSF). However, normal values, especially for children at different ages, are lacking. We collected 1000 specimens of CSF from subjects ranging in age from newborn to 18 years, who were undergoing a diagnostic lumbar puncture for several clinical indications. Of these, 78 samples could be used retrospectively as a reference according to our criteria. The analyses were performed with a modified HPLC procedure. None of the substances shows age-dependency except uridine and uric acid. Uridine increases with age, and uric acid increases with age in boys older than 12 years.  相似文献   
997.
For the detection of the synthesis in vitro of anti-Mycobacterium leprae antibodies in various tissues of leprosy patients, biopsy specimens of skin lesions, nasal mucosa, larynx, lymph nodes, and bone marrow were cultured in a medium containing 14C-labeled lysine and isoleucine. The culture fluids were analyzed by crossed immunoelectrophoresis with intermediate gel and autoradiography. The results show that synthesis of anti-M. leprae antibodies occurs at the investigated sites of leprosy patients and that the specificities of the synthesized antibodies differ between sites in individual patients. It is conceivable that these antibodies play a role in the local defense against M. leprae.  相似文献   
998.
999.
To reduce the effect of electrode position variations on the diagnostic interpretation of an ECG, ECG and VCG interpretations were combined. The reduction was assessed by generating ECGs with displaced electrodes for a group of subjects using Body Surface Potential Maps (BSPMs). VCGs were reconstructed from the ECGs. The group consisted of normals, cases with myocardial infarction (MI), and with left ventricular hypertrophy (LVH). The effects of four types of electrode position changes were assessed for the diagnostic categories MI and LVH. The combined interpretation proved to be less sensitive to large changes than either the ECG or the VCG interpretation alone. The number of small changes increased for the combined interpretation. The combined interpretation showed higher agreement with a human expert than the ECG interpretation alone.  相似文献   
1000.
Purpose To determine the efficacy of a cystoscopic approach, as definitive treatment of ureteral fistulae, after failure of antegrade ureteral stent insertion.Methods Of 43 ureter fistulae encountered over 4 years, 10 postoperative and/or postradiotherapy fistulae could not be stented via an antegrade approach alone. A cystoscopic approach was used, with the antegrade approach available as back-up, if necessary.Results In two patients the ureteral orifice could not be visualized cystoscopically, thus precluding the retrograde approach. In the eight remaining patients, the retrograde approach alone never allowed successful stenting. In six patients, combined antegrade and retrograde approaches permitted stent insertions. In three of those six patients, a complex catheterization procedure was necessary. In two patients the combined approach failed altogether. Therefore, 6 of 10 patients underwent a successful stenting procedure with the combined approach; all ultimately closed the fistula.Conclusion Antegrade stent insertion remains the treatment of choice for ureteral leaks. If the antegrade approach fails, the retrograde approach alone is not likely to be successful. Instead, a combination of both approaches often does succeed.  相似文献   
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