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61.
1引言2006年12月11日是我国正式加入世界贸易组织五周年,也是开放基础电信业务二周年。外资运营商进入中国市场的步伐也有加快的迹象。澳大利亚电讯(亚洲)总裁、澳大利亚电讯(中国)CEO贝裕铭日前表示,澳大利亚电讯要看3G(第三代移动通信)牌照发给哪家运营商,谁来做相关的3G业务,再决定战略性的合作。西班牙运营商Telefonica、新加坡电信、英国沃达丰相关负责人也表达了同样的态度。  相似文献   
62.
蠕变过程中碳化物形貌,类型,数量和分布状态的变化直接影响着材料的高温性能,因而在材料的蠕变得到了广泛的重视,介绍了一种在碳膜萃取复型样品上利用H-800透射电子显微镜的双倾样品台进行了大角度倾转,来观察碳化物形貌并鉴定其类型的试验方法。  相似文献   
63.
3,3'-Iminodipropionitrile (IDPN) causes a permanent syndrome of abnormalities in spontaneous behavior and a deficit in the axonal transport of neurofilaments (NF). Male Long-Evans rats were given IDPN (0, 200, 400, 600, or 1000 mg/kg, ip, in saline) and assessed for behaviors indicative of vestibular function at 1 week post-dosing. The morphology of the peripheral vestibular system in animals dosed with 0, 200, 400, 600, 800, or 1000 mg/kg of IDPN was assessed at 4 days post-dosing by light microscopy on semithin sections. Animals receiving 1000, 1500, or 2000 mg/kg of IDPN were assessed for morphological alterations in the vestibular ganglion at 8 days post-dosing. Behavioral data indicated a dose-dependent loss of vestibular function after IDPN, the vestibular deficits first appearing at the 400 mg/kg dose level. IDPN exposure was also observed to result in degeneration of the vestibular sensory hair cells. Degenerative changes were already found at the 400 mg/kg dose level, and were extensive after 1000 mg/kg. In the ganglion neurons, no effects were observed after 1000 mg/kg of IDPN, but perikaryal accumulations of NF were found after 1500 or 2000 mg/kg. In conclusion, the data showed that low doses of IDPN are toxic to the vestibular hair cells, and suggest a link between this action and the effects of the chemical on spontaneous behavior. In addition, doses of IDPN larger than those required for toxicity to the vestibular sensory cells, induced accumulations of NF in the myelinated cell bodies of the vestibular ganglion neurons.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
64.
通过对热轧左旋带肋钢筋(HRBL600)的质量特性分析,制定了热轧左旋带肋钢筋的化学成分,孔型设计方案和生产工艺。生产实践证明:该产品开发获得成功,产品质量达到标准要求。  相似文献   
65.
过去的几年中,亚洲尤其是中国,已经成为一个酶制剂用量快速增长的市场.中国食品工业的发展从酶生物技术中获益颇多,酶生物技术已成为这种加工助剂为其中的食品工业带来了重大的创新中不可或缺、革新与安全的加工手段之一.  相似文献   
66.
PURPOSE: The relationship between seizure frequency and both health care costs and quality of life (QOL) was investigated in a retrospective, cross-sectional, multicenter study in France, Germany, and the United Kingdom. METHODS: Three hundred outpatients with stable partial epilepsy were approximately evenly distributed among five seizure-frequency groups, ranging from seizure-free in the last 3 months (group 1) to daily seizures (group 5). Economic data, obtained through patient interviews and record abstraction, comprised direct medical costs, direct nonmedical costs, and indirect costs for the preceding 3 months. Total societal costs in the three countries were pooled and converted to United States dollar equivalents. QOL was assessed through a self-administered questionnaire, the Functional Status Questionnaire (FSQ). RESULTS: Mean total costs increased from $780 in group 1 to $2,171 in group 5 (p = 0.0001), with significant increases in each cost category as seizure frequency increased. Greater seizure frequency also significantly (p = 0.0270) correlated with lower employment rates, which ranged from 57% in group 1 to 30% in group 5. QOL declined as seizure frequency increased. Particularly affected were basic and intermediate activities of daily living (ADL), mental health, social activity, and feeling about health. CONCLUSIONS: The study results show that higher seizure frequencies are associated with higher direct and indirect costs and with reduced QOL for patients with epilepsy.  相似文献   
67.
曹达华 《阀门》2007,(3):28-29
通过对双瓣止回阀阀瓣的有限元分析,介绍了有限元分析法在阀门强度和刚度分析方面的应用。  相似文献   
68.
Social support and survival among women with breast cancer   总被引:1,自引:0,他引:1  
BACKGROUND: Two recently reported randomized trials, one among patients with advanced breast cancer and the other among patients with early stage melanoma, suggested that social support may affect survival favorably. This study assesses relationships of social support indicators with 7-year survival among women diagnosed with localized or regional stage breast cancer. METHODS: All newly diagnosed patients with surgically treated localized or regional disease in seven Quebec City hospitals in 1984 were considered for this analysis. Among 235 eligible patients, 224 (95%) participated in a home interview 3 months after surgery. This interview provided information on the use of confidants in the 3 months after surgery. Data on disease and treatment characteristics were abstracted from patients' medical records. RESULTS: Compared with women who used no confidant in the 3 months after surgery, the hazard ratio for the 7-year period was 0.61 (95% confidence interval [CI], 0.33-1.12) among those who had used at least one confidant, 0.54 (95% CI, 0.28-1.06) in women who used two or more types of confidant, and 0.51 (95% CI, 0.22-1.18) among those whose confidants included either physician or nurse. These results were adjusted for age, presence of invaded axillary lymph nodes, adjuvant radiotherapy, and adjuvant systemic therapy (hormone or chemotherapy). CONCLUSION: These results support the view that social support may be associated with longer survival among women with localized or regional stage breast cancer.  相似文献   
69.
The fine specificity of the anti-V3 antibody responses induced in chimpanzees immunized by various human immunodeficiency type 1 (HIV-1) candidate vaccines and challenged by heterologous strains of HIV-1 was analyzed by enzyme-linked immunosorbent assay (ELISA) and Pepscan epitope mapping. Two chimpanzees immunized with the recombinant canarypox virus ALVAC-HIV (vCP125) expressing gp160MN and boosted with purified gp160MN/LAI alone, then with both immunogens in combination, were not protected against challenge with HIV-1 SF2. Their sera mainly recognized one epitope of the V3 loop, located in the NH2-terminal half. By contrast, immunization of two other chimpanzees with purified gp160MN/LAI and boosting with a synthetic V3MN peptide elicited a strong anti-V3 antibody response with a broader specificity directed against multiple epitopes all along the V3 loop. These chimpanzees were protected against infection by HIV-1 SF2. However, when these two chimpanzees were challenged later with a HIV-1 clade E strain virus, they became infected. We failed to detect any reactivity with the peptide of the ectodomain of gp41 of sera harvested after immunization with the various immunogens or after challenge with HIV-1 SF2 or HIV-1 90CR402. These results demonstrated that anti-V3 antibodies with a restricted fine specificity were induced in chimpanzees immunized with gp160 purified or expressed by recombinant canarypox confirming our previous results obtained in three different species (human, guinea pig and, macaque). In contrast, a boost with the V3 peptide broadened antibody responses, suggesting that the mode of presentation of the V3 loop to the immune system strongly influences the epitope specificity of the resulting antibody response.  相似文献   
70.
BACKGROUND: Despite numerous studies of partial mastectomy and psychologic morbidity in the first 24 months following surgery, little is known about the long term psychosocial repercussions of partial and total mastectomy. METHODS: The effect of the type of mastectomy on psychologic adjustment was assessed among 124 breast carcinoma survivors, 47 of whom underwent partial mastectomy and 77 of whom underwent total mastectomy, 8 years after initial treatment. Interviews were also conducted 3 and 18 months after surgery. Psychologic distress was assessed using the Psychiatric Symptom Index. Other outcomes included physical symptoms, patients' perceptions of their own health, satisfaction with the type of surgery performed and with the appearance of the scar, and marital and sexual adjustments. RESULTS: No statistically significant differences between partial and total mastectomy were observed with respect to long term quality of life. Age at diagnosis modified the relation between the type of mastectomy and psychologic distress in both the short term and the long term (P = 0.04). Among women younger than 50 years, partial mastectomy appeared to be protective against distress when compared with total mastectomy. In contrast, among women age 50 years or older, partial mastectomy was associated with higher psychologic distress levels at all interviews. CONCLUSIONS: Assessed globally, partial and total mastectomy appear to be equivalent treatments in terms of patients' long term quality of life. However, both short term and long term distress levels after partial and total mastectomy may depend on patients' age at diagnosis. The findings of this study suggest that the increased use of partial mastectomy may lessen the negative effects of breast carcinoma on younger survivors' quality of life. Nevertheless, total mastectomy may be an appropriate initial treatment for some women who truly choose it.  相似文献   
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