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11.
台湾电信市场的开放大致分四个阶段,从1995年起,陆续开放了移动通信、卫星通信及固定通信等多种业务。固网市场,2001年新世纪资通、台湾固网和力霸宽频电信的加入打破了中华电信的独家垄断,开始形成四强竞争的新局面。移动领域,1997年底6家运营商8张民营执照的发放开始了该领域史无前例的竞争。在2001年1月,台湾大哥大、远致电信、亚太行动宽频、联邦电信和中华电信获得了3G执照,累计竞标金额达488.99亿元(新台币)。 相似文献
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J Jassem H Karnicka-M?odkowska C van Pottelsberghe M van Glabbeke MA Noseda A Ardizzoni F Gozzelino A Planting N van Zandwijk 《Canadian Metallurgical Quarterly》1993,(12):1720-1722
26 previously treated patients with progressive recurrent small cell lung cancer (SCLC) were given vinorelbine (Navelbine), 30 mg/m2 weekly. All patients had responded to first-line chemotherapy and were off therapy for at least 3 months. Partial response was observed in 4 out of 25 eligible patients (16%; 95% confidence interval 4-36%), stable disease in 7 patients and progression in 12 patients. The limiting toxicity was a non-cumulative leucopenia (80%, 32% WHO grade 3-4). Reaction at the site of injection was observed in 5 patients, causing treatment discontinuation in 2 cases. Other non-haematological toxicities were moderate. These results suggest acceptable toxicity and some antitumour activity of vinorelbine in pretreated SCLC patients. 相似文献
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Bo Jiang Jeffrey L. Brown Jane Sheraton Nathalie Fortin Howard Bussey 《Yeast (Chichester, England)》1994,10(3):341-353
We have identified three yeast genes, KES1, HES1 and OSH1, whose products show homology to the human oxysterol binding protein (OSBP). Mutations in these genes resulted in pleiotropic sterol-related phenotypes. These include tryptophan-transport defects and nystatin resistance, shown by double and triple mutants. In addition, mutant combinations showed small but apparently cumulative reductions in membrane ergosterol levels. The three yeast genes are also functionally related as overexpression of HES1 or KES1 alleviated the tryptophan-transport defect in kes1Δ or osh1Δ mutants, respectively. Our study implicates this new yeast gene family in ergosterol synthesis and provides comparative evidence of a role for human OSBP in cholesterol synthesis. 相似文献
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'Borderline' methicillin-resistant Staphylococcus aureus (MRSA) strains are inhibited by drug concentrations of 2 to 8 micrograms/mL. This type of resistance is usually mediated by 'hyper beta-lactamase' production which is detectable in vitro by susceptibility to combinations of a beta-lactam and a beta-lactamase inhibitor (ie, amoxicillin and clavulanic acid). A survey of Canadian infection control experts was performed to assess the knowledge, attitudes and beliefs regarding the containment requirements for borderline MRSA strains in acute health care facilities. Twenty-three of 38 Canadian infection control experts (61%) (members of the Canadian Hospital Epidemiology Committee [CHEC] or the Society for Healthcare Epidemiology of American [SHEA]) returned a questionnaire about a fictional patient with a postoperative wound infection with such a strain. Eleven respondents (48%) considered the isolate as an MRSA, 11 did not and one was unsure. All who did not believe the strain to be MRSA would not have isolated or cohorted the patient. Four in the latter group would have isolated the patient if he or she were on a neurosurgery or cardiovascular surgery unit, indicating a desire to restrict spread of this isolate on those units. Seven of the 12 individuals who had managed at least one patient with a borderline MRSA did not advocate patient isolation or cohorting, and five did. This survey has supported the belief that there are discrepancies among infection control decision-makers in Canada regarding the approach, precautions and therapy of patients infected with borderline strains of MRSA. Further data on virulence of and effective therapy for these isolates are needed to assess whether the additional cost is warranted in controlling the nosocomial spread of these isolates. 相似文献
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本文对白云鄂博主矿采场铁公路联合运输向公路运输转换位置是否确定为1638m水平以及运输工艺转换过程中相关问题进行分析论证,提出主矿采场铁路至少可向下延深一个水平,技术上可行,节约运费千万元以上。 相似文献
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