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991.
To evaluate the potential advantages of the administration of extradural morphine to control postoperative pain and its effects on respiratory function, 39 patients were randomly assigned to one of two groups before aortic surgery. The first group (20 patients) received intravenous analgesia as required (control group). The second group (19 patients) received extradural morphine in a programmed fashion. During the immediate postoperative period the following parameters were measured in both groups: respiratory rate, vital capacity, peak expiratory volume in the first second, PaO2, PaCO2, arterial pH, heart rate, and systolic and diastolic blood pressure. In the group treated with morphine the postoperative increase in heart and respiratory rate was significantly smaller than in the control group (p less than 0.01). Postoperative forced pulmonary volumes were higher in the morphine group (p less than 0.01). However, there were no differences in time of hospitalization between both groups. There were more complications in the control group, but the difference did not reach statistical significance.  相似文献   
992.
In 1987, we reported the 1-year migration of the prosthetic components in 16 hips followed by roentgen stereophotogrammetry after fixation with either low- or high-viscosity cement. We now report the migration of these prosthetic components during another 2 postoperative years. Eight acetabular components, four in each group, migrated cranially; and four femoral components, three in the low-viscosity and one in the high-viscosity group, migrated distally. All but two migrations were obvious 4 months postoperatively, which indicates that what is called late loosening is the result of late detection rather than of late occurrence of loosening. Low-viscosity cement did not provide improved prosthetic fixation.  相似文献   
993.
Summary Glial cell line-derived neurotrophic factor (GDNF) is a potent neurotrophic factor for dopaminergic neurons. Since dopaminergic neurons degenerate in Parkinson's disease, this factor is a potential therapeutical tool that may save dopaminergic neurons during the pathological process. Moreover, a reduced GDNF expression may be involved in the pathophysiology of the disease. In this study, we tested whether altered GDNF production may participate in the mechanism of cell death in this disease. GDNF gene expression was analyzed by in situ hybridization using riboprobes corresponding to a sequence of the exon 2 human GDNF gene. Experiments were performed on tissue sections of the mesencephalon and the striatum from 8 patients with Parkinson's disease and 6 control subjects matched for age at death and for post mortem delay. No labelling was observed in either group of patients. This absence of detectable expression could not be attributed to methodological problems as a positive staining was observed using the same probes for sections of astroglioma biopsies from human adults and for sections of a newborn infant brain obtained at post-mortem. These data suggest that GDNF is probably expressed at a very low level in the adult human brain and its involvement in the pathophysiology of Parkinson's disease remains to be demonstrated. GDNF may represent a powerful new therapeutic agent for Parkinson's disease, however.  相似文献   
994.
79 patients with ischaemic stroke were investigated, with 31 patients showing a pure hemiparesis, 22 an additional depressive syndrome and 26 a dementia. After an average time intervall of 28 months, a follow-up investigation was performed on these 3 groups relative to their course and rehabilitation outcome. No significant differences were present between the 3 groups as regards age and sex distribution as well as hemisyndrome severity. The neurological and psychiatric findings at follow-up differed significantly from the primary findings. Also, significant differences were found in the degree of disability, and in the self- and family ratings of rehabilitation outcome, with a poorer long-term course, i.e. a higher degree of disability, significantly more frequent in the dementia group. Comparison of self- and family-ratings showed that self-ratings given were significantly worse in the dementia and depressive groups, whereas patients with purely neurological symptoms rated themselves better than their relatives did.  相似文献   
995.
In order to investigate the possibility of using [1-11C] labelled 3,4-dihydroxyphenylalanine (DOPA) and tyrosine as radiopharmaceuticals for the detection of eye melanoma, the biodistributions of the same 1- and 3-14C-labelled compounds were investigated in Syrian golden hamsters with Greene melanoma. The results of these investigations were compared with positron emission tomography (PET) images of 11C labelled DOPA and tyrosine. The synthesis of these 11C labelled compounds procures of DL mixture, from which D and L forms can be separated. One h after intravenous injection, both 14C labelled DL-, L- and D-DOPA showed a high uptake in tumour tissue, that of DL- and D-DOPA being the highest. These high uptakes, together with relatively low uptake in bone, skin and eye resulted in high tumour/non tumour ratio (for DL-DOPA 5.9, 4.5 and 6.6 respectively). Extraction of the tumour tissue with trichloroacetic acid showed that L-DOPA was mainly incorporated into melanin, whereas D-DOPA was not. Also, the uptake 1 h after intravenous injection of 1-14C-L- and DL-tyrosine into the tumour were high, but L- and DL- were less different; tumour/non tumour ratios were favorable. PET images of the tumour obtained 40-80 min after injection of the [1-11C] labelled DOPA and tyrosine confirmed that melanoma detection was promising and that D-DOPA produced a better melanoma image than L-DOPA.  相似文献   
996.
997.
998.
Thirty six patients were studied with a classical photoparoxysmal EEG response to intermittent photic stimulation (IPS). Clinical observations and complaints reported by patients during standardised IPS were recorded and compared with historical data. Twenty seven patients experienced impaired consciousness or showed motor phenomena such as involuntary opening of the eyes or jerking on one or both sides of the body. Twenty five patients had sensations such as pain in the eyes, jerking etc. There existed no relation between the duration of the evoked discharges (0.5-3 seconds) and observed signs or complaints. In 11 instances the clinical features found during IPS were not reported in a history taken from the patient and relatives.  相似文献   
999.
1000.
Malignant rhabdoid tumors are highly aggressive childhood tumors. Recently, all of the malignant rhabdoid tumors, whatever their location, have been related to the inactivation of the hSNF5/INI1 gene. A subset of cerebral tumors, associated with malignant rhabdoid tumors or isolated ones arising in siblings, showed similar molecular alterations. We report for the first time in monozygotic twins a congenital disseminated malignant rhabdoid tumor in one twin and a cerebellar tumor mimicking a medulloblastoma in the other. Molecular analysis revealed similar alterations for both tumors: a deletion of exon 7 of the hSNF5/INI1 gene in one allele, and a point mutation in the same exon in the other, suggesting a common genetic pathway. Analysis of constitutional DNA revealed a germline mutation. These findings are in favor of a common etiology for rhabdoid tumor and a subset of brain tumors developing in infancy.  相似文献   
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