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991.
Multidisciplinary evaluation of rat renal cell carcinoma 总被引:1,自引:0,他引:1
H F Karthaus W F Feitz A P vd Meijden J A Schalken J L Beck B T Hendriks P H Jap G P Vooijs F M Debruyne F C Ramaekers 《In vivo (Athens, Greece)》1987,1(6):335-341
The rat renal cell carcinoma system as described by deVere White and Olsson in 1980 is used widely as a model for its human counterpart. The tumor arose spontaneously in a male Wistar Lewis rat and its behaviour has been shown to be stable during multiple passages. We have compared this tumor with the human renal cell carcinoma using a multidisciplinary approach. Light microscopy and electron microscopy showed a great resemblance of this rat tumor to a human renal cell carcinoma of the clear cell type with the ultrastructural presence of desmosomes. With the use of tissue specific antibodies against intermediate filament proteins, it could be shown that their expression is comparable to human renal cell carcinoma, i.e. coexpression of vimentin and different cytokeratins in the tumor cells. The cells could also be shown to contain cytokeratin 18. An aneuploid cell population in the tumor, expressing both vimentin and keratin, could be characterized by DNA flow cytometry in double labeling experiments. Comparison of normal and malignant rat kidney tissue by Northern blot analysis revealed increased levels of vimentin mRNA. In conclusion, this tumor model seems to have several histological and biological properties in common with the human renal tumor. 相似文献
992.
993.
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
994.
Intubating conditions after vecuronium and atracurium given in divided doses (the priming technique)
R. K. Mirakhur G. G. La Very F. M. Gibson R. S. J. Clarke 《Acta anaesthesiologica Scandinavica》1986,30(5):347-350
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
995.
The history and epidemiology of bovine tuberculosis in cattle herds in East Sussex are described. Since 1960, following the compulsory eradication scheme for tuberculosis, the incidence of herd infection has been low. The epidemiological features of herd infection have been sporadic incidents, with only small numbers of cattle becoming infected in the majority of incidents. There was no evidence of endemic Mycobacterium bovis infection in the cattle population in East Sussex in recent years, but a low risk of infection for cattle on the South Downs, from badgers, was apparent. 相似文献
996.
997.
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999.
The spread of Brucella infection in man in Italy during the last three years is briefly reviewed with reference to the Brucella strains collected and typed.The strains were tested by H2S production, dye-inhibition, agglutination by monospecific sera, and sensitivity to a phage set. From 108 tested strains, 91 have been identified by means of the traditional tests as Br. melitensis, sometimes with some irregularities, 10 as Br. abortus, while 7 were not typable.It was possible to recommend some phage sensitivity patterns of Br. melitensis for epidemiological purposes: one phagotype is much more frequent in the north, another in the south of Italy.However, the currently recommended phagotypes must be considered provisional and will be modified in the light of more extensive studies.Corresponding author. 相似文献
1000.
Comparison of two in vitro methods of bone lead analysis and the implications for in vivo measurements 总被引:4,自引:0,他引:4
L J Somervaille D R Chettle M C Scott A C Aufderheide J E Wallgren L E Wittmers G R Rapp 《Physics in medicine and biology》1986,31(11):1267-1274
Atomic absorption spectrometry and x-ray fluorescence have been used to determine the lead content of metatarsal and tibia bone samples. For a range of bone lead levels from 6.5 to 83 micrograms g-1 of ashed bone there is no evidence of a systematic difference between the two techniques of more than 1 microgram g-1. There is, however, some evidence that random differences between the two in vitro analyses applied to the same bone sample are larger than can be accounted for by known measurement uncertainties. Variations in bone composition could account for these differences. Because the x-ray fluorescence technique is applied in an identical way to in vivo analysis, it is concluded that the uncertainties in in vivo measurements are small. 相似文献