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951.
A crossover double-blind controlled trial was performed on 36 patients with rheumatoid arthritis to assess the necessity for serum salicylate monitoring in determining optimal dosage. There was no clinically or statistically significant increase in the clinical improvement of patients associated with serum monitoring but potentially toxic serum levels occurred without tinnitus when serum monitoring was not used.  相似文献   
952.
953.
In comparative histological and cytological studies on 270 prostatic carcinoma patients highly and moderately differentiated tumors were found to be more frequent histologically than cytologically. An early and reliable sign of response to hormone therapy proved to be reticularization and vacuolization of the nuclear chromatin. Follow-up studies by means of multiple aspiration biopsies with cytologic examinations seem to be more reliable in prognostic terms than examination of the histological tumor structure.  相似文献   
954.
The authors present an improvement to a sigma-filter extrapolation method for the reconstruction of magnetic resonance (MR) images from symmetric discrete Fourier data. By making use of the phase information in the image data, the proposed method can overcome the data inconsistency problem of the original method for handling MR image data with large phase variations, such as those obtained in gradient-echo pulse sequences. Reconstruction results show that its performance is comparable with that of the modified complex sigma-filter method proposed previously to handle the inconsistency problem. However, the new approach has the advantage of reducing computation time by a factor of two with use of a sigma filter applied to real instead of complex images. It is expected that this method will be more practical for use in clinical MR imaging systems.  相似文献   
955.
Seventy seven antral biopsies were collected from patients attending endoscopy clinic at King Khalid University Hospital, Riyadh, Saudi Arabia during a period of six months between December 1988 to May 1989. Of these 69 (89.6%) showed chronic gastritis as well as Helicobacter-like organisms (HLOs) in the biopsy specimens while 63 (81.8%) of biopsies grew Helicobacter pylori on culture. These findings indicate a good correlation between the histological diagnosis of chronic gastritis and isolation of H. pylori on culture.  相似文献   
956.
Electrical activity was recorded from single cells in the thalamus of 10 patients with chronic pain associated with deafferentation. Under local anesthesia, these patients underwent either electrode implantation or thalamotomy for treatment of their pain. In eight of the 10 patients, single units were identified as discharging spontaneously in high-frequency, often rhythmic, bursts. The discharges were of two types: short bursts comprised of two to six spikes with a burst frequency of one to four per second; and long trains of 30 to 80 spikes of similar frequency. Reconstruction of electrode trajectories indicated that recordings were made from the region corresponding to the lateral aspect of the mediodorsal thalamic nucleus, the central lateral nucleus, a small part of the central median nucleus, and the parafascicular nucleus. In the eight patients in whom spontaneous neuronal burst activity was exhibited, it was impossible to study activity evoked by natural cutaneous stimulation due to the continuous spontaneous neuronal discharges. Both animal and human studies have suggested that pain related to deafferentation is accompanied by spontaneous hyperactivity in the dorsal horn of the spinal cord and in the ventral posterior thalamic nuclei. The authors present evidence of spontaneous neuronal hyperactivity in the intralaminar thalamic nuclei of patients with pain related to deafferentation. The findings suggest that spontaneous neuronal discharge in patients with pain related to deafferentation is more widespread in the central nervous system than has been previously appreciated. The results have important implications for the surgical treatment of chronic pain.  相似文献   
957.
To measure prefrontal and subcortical activity during a cognitive task, we examined 19 newly diagnosed schizophrenics and patients with schizophreniform psychosis. Seven healthy volunteers served as controls. The patients were drug naive or had received neuroleptics for a few days only. Cerebral blood flow distribution was depicted by single photon emission computed tomography at rest and during activation with the Wisconsin Card Sorting Test. A significant relative activation deficit in the left inferior-prefrontal region was revealed during the Wisconsin Card Sorting Test in the patient group. Furthermore, the patients had impaired striatal suppression on the left side during the cognitive task. The test performance was significantly impaired in the patients. The inability to reduce striatal activity may be due to a lack of corticostriatal feedback during prefrontal activation.  相似文献   
958.
Biliary atresia is the most common indication for orthotopic liver transplantation (OLT) in children. The polysplenia syndrome anomalies, which occur in approximately 10% of children with biliary atresia, may represent special difficulties at liver transplantation. We have reviewed our experience with this syndrome in 116 children with biliary atresia who underwent liver transplantation between March 1984 and December 1989. The main features of the polysplenia syndrome, which included absence of the inferior vena cava, preduodenal portal vein, midgut malrotation, aberrant hepatic artery, and situs inversus, were encountered in 12 of the 116 children (10.3%). Severe portal vein hypoplasia (3.5 mm or smaller) was also present in 7 of these children. Eight patients received a complete and four received a reduced liver graft. The vascular anomalies increased the technical difficulty of OLT but could be surmounted, although they did contribute to the peroperative death of one child. The 1-month survival rate was 83% for the 12 children with features of the polysplenia syndrome and 88% for the other 92 children with biliary atresia alone.  相似文献   
959.
With topical therapy using dinitrochlorobenzene (DNCB), 36 (72%) out of 50 patients having alopecia areata showed regrowth of hair in 3 to 6 months time. Five (10%) patients experienced marked vesiculation and severe contact dermatitis requiring cessation of therapy. In 7 (14%) patients there was no response at all and 4 (8%) presented with other side-effects.  相似文献   
960.
Existing triage algorithms consider, for the most part, only the primary casualty with physical trauma. Algorithms fail to appreciate the primary, secondary, or tertiary neuropsychiatric casualty. Research advances on neuropsychiatric casualties must link with the mandates of emergency medical services and disaster management to improve triage sensitivity and specificity. Early recognition and management of neuropsychiatric casualties will diminish the potential for long-term consequences. Expanded triage algorithm supplements are proposed to improve the recognition of those victims at risk.  相似文献   
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