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DD Coelho 《Canadian Metallurgical Quarterly》1997,73(5):397-398
Thoracic infection by anaerobes are uncommon diseases and often presents difficulty in diagnosis. We report a case of thoracic infection due to Fusobacterium Nucleatum. A 60-year old man presented a lesion infiltrating from the lung to the thoracic wall. Fusobacterium Nucleatum was isolated on pus collected. Treatment by penicillin, metronidazole combined with surgical drainage was highly effective. 相似文献
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Gene amplification in a p53-deficient cell line requires cell cycle progression under conditions that generate DNA breakage 总被引:1,自引:0,他引:1
Amplification of genes involved in signal transduction and cell cycle control occurs in a significant fraction of human cancers. Loss of p53 function has been proposed to enable cells with gene amplification to arise spontaneously during growth in vitro. However, this conclusion derives from studies employing the UMP synthesis inhibitor N-phosphonacetyl-L-aspartate (PALA), which, in addition to selecting for cells containing extra copies of the CAD locus, enables p53-deficient cells to enter S phase and acquire the DNA breaks that initiate the amplification process. Thus, it has not been possible to determine if gene amplification occurs spontaneously or results from the inductive effects of the selective agent. The studies reported here assess whether p53 deficiency leads to spontaneous genetic instability by comparing cell cycle responses and amplification frequencies of the human fibrosarcoma cell line HT1080 when treated with PALA or with methotrexate, an antifolate that, under the conditions used, should not generate DNA breaks. p53-deficient HT1080 cells generated PALA-resistant variants containing amplified CAD genes at a frequency of >10(-5). By contrast, methotrexate selection did not result in resistant cells at a detectable frequency (<10(-9)). However, growth of HT1080 cells under conditions that induced DNA breakage prior to selection generated methotrexate-resistant clones containing amplified dihydrofolate reductase sequences at a high frequency. These data demonstrate that, under standard growth conditions, p53 loss is not sufficient to enable cells to produce the DNA breaks that initiate amplification. We propose that p53-deficient cells must proceed through S phase under conditions that induce DNA breakage for genetic instability to occur. 相似文献
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L Magaudda MR Mondello DD Di Mauro S Pallio M Bottari 《Canadian Metallurgical Quarterly》1996,42(2):61-69
The effects of antiepileptic drugs on cognitive function in 48 healthy volunteers were assessed using event-related potentials (ERP) and the Attention Index included in the Wechsler Memory Scale, revised edition (WMS-R). The study was conducted over 1 week, using a double-blind design. Four drugs, carbamazepine (CBZ), phenytoin (PHT), valproate (VPA) and zonisamide (ZNS) were tested. Using an auditory oddball task, ERP measurements were made under two conditions with different tone intensities: Condition 1 used 70 db SPL; and Condition 2 used 30 db SPL. Results showed that CBZ prolonged target N1 and P3 latencies in Condition 1, and reduced frequent N1 amplitude in Condition 2, which suggests that CBZ may cause a change in sensory memory and prolong stimulus evaluation time. It is suggested that under a low stimulus intensity level, the sensory function itself was affected. Phenytoin was found to prolong target N1 latency in Condition 2, which also indicates a change in the sensory memory function. However, VPA did not significantly affect ERP components, except for the shortened frequent N1 latency, which could not be explained due to the limited information. It was found that ZNS augmented P3 amplitude in Condition 2, and reduced scores on the Attention Index. It is suggested that the augmentation of P3 amplitude was caused by the reduction of processing negativity as a result of the detrimental effect of ZNS on subjects' attention. However, the apparent difference between the ERP and behavioral indices suggests that caution should be exercised in assessing the results obtained only from ERP measurements. 相似文献
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JJ Callaghan GS Tooma JP Olejniczak DD Goetz RC Johnston 《Canadian Metallurgical Quarterly》1996,(333):118-125
The senior authors' initial experience with primary hybrid hip replacement in patients with osteoarthritis was studied to evaluate the efficacy of the procedure. Hybrid total hip arthroplasty (uncemented Harris-Galante acetabular component and cemented Iowa precoated femoral component) was performed in 131 consecutive, nonselected hips in 118 patients with the diagnosis of primary osteoarthritis. Followup was performed at 8 to 9 years after the procedure. The average age at the time of the procedure was 68 years (range, 45-87 years). There were 50 men (55 hips) and 68 women (76 hips). At final followup 19 patients (22 hips) had died. The femoral component had been revised for aseptic loosening in 8 hips (6.1%). One additional hip showed definite radiographic loosening. Hence, the prevalence of radiographic femoral failure was 6.9% (9 hips). No acetabular component had been revised for aseptic loosening and no acetabular component had migrated. The senior author continues to perform hybrid total hip arthroplasty in all patients with primary osteoarthritis. However, design modifications have been made in the femoral component that is used. 相似文献