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991.
992.
The ganglioside composition of human melanoma was analyzed in five sets of tumor specimens obtained directly from surgery, from the autologous tissue culture cell lines, and from the autologous cell lines grown in athymic nude mice. Total gangliosides of these 15 melanoma specimens were isolated and purified, and the amount of each component ganglioside was analyzed by thin-layer chromatography and a thin-layer chromatography scanner. The ganglioside composition of the five surgical melanoma specimens clearly exhibited different patterns from each other. Moreover, none of the autologous cultured melanomas possessed the same ganglioside composition as their original biopsied tumors. However, when these melanoma cell lines were transplanted into nude mice, the ganglioside composition was converted back to the same ganglioside pattern as in the original surgical specimens. The results support the view that changes in the ganglioside composition of melanoma during in vitro growth are caused by the culture environment rather than by selection of melanoma cells with a particular genotype. Reestablishment of the original ganglioside patterns after passage in nude mice provides clear evidence that in vivo expression of gangliosides is a conserved and stable function specified by the human melanoma cells.  相似文献   
993.
Summary The authors report 165 cases of thoraco-lumbar lesions with neurological dysfunction. All the patient were operated. They analyze the neurological and mechanical results and indicate the use of different osteosynthesis apparatus according to the type and level of lesions.Harrington's rods seem to give more precise repositioning while Roy Camille's plates give more stability. When the posterior wall of the spinal canal is intact, Kempf's compression rods can be used.Thoraxic spine injuries seem to be an indication for Harrington's rods, while lumbar injuries seem to call for Camille's plates.  相似文献   
994.
Intrathecal morphine for post-thoracotomy pain   总被引:1,自引:0,他引:1  
We wished to investigate possible differences in the duration of postoperative analgesia and the incidence of respiratory depression after the intrathecal injection in the lumbar area of 10 micrograms/kg morphine in hypobaric and hyperbaric solution for relief of post-thoracotomy pain. Twenty-nine patients received morphine plus dextrose (hyperbaric) and 21 received morphine in preservative-free normal saline. The duration of analgesia was longer with the morphine in the normal saline group than in the hyperbaric group (P less than 0.04). One patient developed delayed respiratory depression. Our data support the use of morphine in normal saline mixtures for greater duration of analgesia after thoracic operations.  相似文献   
995.
Intubating conditions have been assessed at 60 s following administration of vecuronium 0.1 mg kg-1 or atracurium 0.5 mg kg-1 given either as a single dose after induction of anaesthesia with thiopentone or in divided doses; vecuronium 0.015 mg kg-1 followed 4 or 6 min later by 0.085 mg kg-1, or atracurium 0.075 mg kg-1 followed 4 or 6 min later by 0.425 mg kg-1. In the divided dose groups the smaller initial (priming) dose was given prior to induction of anaesthesia. Onset and duration of clinical relaxation were assessed using a peripheral nerve stimulator. The intubating conditions at 60 s improved significantly, with the use of relaxants in divided doses being acceptable in 80 and 70% of patients, respectively, with vecuronium and atracurium, but the conditions are not as good as those commonly found using suxamethonium. Priming at 6 min has no advantage over priming at 4 min. The onset of complete block was accelerated with priming, but the difference was not significant. The duration of clinical relaxation of vecuronium was significantly prolonged by giving it in divided doses. Unpleasant awareness of muscle weakness was observed in 15 patients, requiring early induction of anaesthesia in five of them.  相似文献   
996.
997.
S E Bedell  D Pelle  P L Maher  P D Cleary 《JAMA》1986,256(2):233-237
We studied compliance with do-not-resuscitate (DNR) orders at a university hospital where a DNR protocol has existed since 1979. Documentation of DNR status in patient progress notes and chart orders increased through 1983. During a 12-month period (March 1983 through April 1984), we studied in detail the medical records of 521 patients who had a cardiopulmonary arrest in the hospital. Seventy-five percent (389 of 521) of these patients were designated DNR. Patients who were designated DNR were significantly more likely to be older, to have malignancy or an abnormal mental status, and to be less likely to have acute myocardial infarction, stroke, or chronic obstructive pulmonary disease than patients in whom resuscitation was attempted. Eighty-six percent of families, but only 22% of patients, were involved in the decision to designate a patient DNR. The decision to designate a patient DNR occurred late in the course of a patient's illness, often when the patient was in coma. For 28% of patients, some form of medical care was withdrawn or withheld after they were designated DNR. These data suggest that use of the DNR protocol requires changes if patients are to participate in the decision not to undergo cardiopulmonary resuscitation.  相似文献   
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