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1.
The original article to which this Erratum refers was published in Pharmacoepidemiology and Drug Safety 2005; 14: 239–247.  相似文献   
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Periosteal Ewing sarcoma   总被引:3,自引:0,他引:3  
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AIMS: Human herpesvirus 8 (HHV-8) has been identified in multicentric Castleman's disease and in angioimmunoblastic lymphadenopathies. However, the presence of the virus does not necessarily indicate an aetiological role in these conditions. This study investigates the cell types infected by HHV-8 in Castleman's disease and examines the correlation between HHV-8 and Castleman's disease lymph node angiogenesis. METHODS: Sixteen formalin fixed, paraffin wax embedded samples from patients with Castleman's disease (six multicentric, 10 solitary) were examined for the presence of HHV-8 using the polymerase chain reaction (PCR), non-isotopic in situ hybridisation, PCR in situ hybridisation (PCR-ISH), and real time quantitative TaqMan PCR to HHV-8 open reading frame 26 (ORF-26), and viral (v)-cyclin encoding regions. Vascularity was assessed using CD34, CD31, and factor VIII immunocytochemistry, and lymph nodes were scored as "low" or "high". RESULTS: Five multicentric Castleman's disease and two solitary Castleman's disease biopsies were positive for HHV-8. HHV-8 was identified in approximately 10% of intranodal B lymphocytes, in endothelial cells, and in subcapsular spindle cell proliferations. The copy number of HHV-8 was low at 10-50 copies/1000 cells. The highest copy number was in subcapsular spindle cells. There was no correlation between vascularity score and HHV-8 status. CONCLUSION: The preferential localisation of HHV-8 in subcapsular spindle cell proliferations (where early intranodal Kaposi's sarcoma initiates) and endothelial cells in Castleman's disease might finally explain the link between intranodal Kaposi's sarcoma and Castleman's disease.  相似文献   
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AIMS: Kaposi's sarcoma is a vascular tumour of uncertain pathogenesis possibly caused by an infectious agent, identified in high risk groups. Accumulating solution phase polymerase chain reaction (PCR) and seroepidemiological data suggest that a previously undescribed herpes DNA virus (human herpesvirus 8 (HHV8)) is the causative agent. Using a unique cohort of early Kaposi's sarcoma, the precise cell type infected with HHV8 in such lesions was identified to elucidate further the role of HHV8 in the pathobiology of Kaposi's sarcoma. METHODS: Sixteen cases of early Kaposi's sarcoma (derived from skin and lymph node) were assessed for the presence of HHV8 using both standard solution phase PCR and TaqMan PCR to the KS330 Bam region of HHV8. In situ amplification was also performed on a selected group in an attempt to identify the candidate infected cells. RESULTS: Using both conventional solution phase and TaqMan PCR, 87% of cases were positive. In addition, HHV8 amplicons were localised in situ to endothelial and spindle cell proliferations in early Kaposi's sarcoma. The HHV8 viral load varied from lesion to lesion. CONCLUSIONS: The presence of HHV8 in early lesions supports a role for HHV8 in the pathogenesis of Kaposi's sarcoma. Coupled with recent seroepidemiological studies, these results suggest that HHV8 is the aetiological agent of Kaposi's sarcoma. Its precise interaction with other factors known to be involved in the development of Kaposi's sarcoma, including cytokines and anti-apoptosis genes, requires elucidation.  相似文献   
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同种异体黑素细胞移植治疗白癜风   总被引:2,自引:2,他引:0  
卢涛  高天文  刘玉峰  李春英  孙林潮 《医学争鸣》2001,22(12):1147-1147
0 引言 白癜风患者免疫紊乱 ,黑素细胞 (melanocyte,MC)异体移植有可能不被排斥 ,治疗如成功将有很大临床前景 [1 ] .探索同种异体黑素细胞移植后的效果很有意义 .1 病例报告 女 ,2 7岁 ,确诊白癜风 (稳定期 ) ,患者皮肤自幼出现色素脱失斑 ,逐渐增多扩大 . 1996年外用“敏白灵”,前2 mo有效 . 1999- 0 7外用补骨酯酊 ,日服 5 g· L- 1 硫酸铜 10m L和中药 1剂 ,转移因子 4m L ,sc,1· 2 d- 1 .皮损缩小 ,4mo后稳定 .用健康男青年环切的包皮培养 MC,第 4代大约80 %融合时 ,用 2 .5 g· L- 1 胰酶消化 5 min,加入含 2 0 0 g·L- 1小…  相似文献   
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Otten LJ  Alain C  Picton TW 《Neuroreport》2000,11(4):875-880
Auditory evoked potentials were recorded while participants attended to visually presented digits. The difficulty of the visual task was manipulated by requiring participants to process only the current digit (0-back) or both the current and the preceding digit (1-back). Tones deviating in frequency from standard tones elicited a frontal mismatch negativity peaking around 200 ms which did not vary with visual task. However, decreasing the visual task load enhanced a right-temporal positive wave peaking around 200 ms when tones were presented slowly, and a frontocentral negative wave peaking around 450 ms when tones were presented more rapidly. The degree to which task-irrelevant sounds are processed therefore depends on the degree to which a visual task engages attentional resources.  相似文献   
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Polycystic ovary syndrome (PCOS) is a heterogeneous syndrome. In vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) is required for PCOS cases that are refractory to standard ovulation induction or have co-existing infertility factors in women with PCOS and Tubal factor subfertility. OBJECTIVES: Assess ethnic variations in response to IVF/ICSI treatment. STUDY DESIGN: Observational Comparative study in a University hospital fertility clinic in women with PCOS and Tubal factor subfertility. Women with PCOS (Asians: AP=104; Caucasians: CP=220) and those with tubal factor infertility seeking fertility treatment were assessed (Asians: AC=84; Caucasians: CC=200). Six hundred and eight fresh IVF or ICSI cycles using long protocol of GnRHa suppression and resulting in a fresh embryo transfer were compared. The primary endpoint was to assess the dose of gonadotropins used in the cycles. The secondary outcomes were: total number of oocytes retrieved, fertilization and ongoing clinical pregnancy rates. RESULTS: We found that the South Asian women presented at a younger age for the management of sub-fertility. An extended stimulation phase and Caucasian ethnicity showed an inverse correlation with the number of oocytes retrieved in the PCOS subgroup. Caucasian ethnicity was associated with a higher fertilization rate however increase in body mass index (BMI) and the laboratory technique of IVF appeared to have a negative impact on fertilization rates in the PCOS subgroup. Commencing down regulation on day 1 of the cycles was negatively associated with fertilization rates in the tubal group. In terms of clinical pregnancy rates, the Caucasian PCOS had a 2.5 times (95% CI: 1.25-5) higher chance of an ongoing clinical pregnancy as compared with their Asian counterpart. Also, a unit increase in the basal FSH concentration reduced the odds of pregnancy by 18.6% (95% CI: 1.8-32.6%) in the PCOS group. CONCLUSIONS: The Asian PCOS have a greater sensitivity to gonadotropin stimulation with lower fertilization and ongoing clinical pregnancy rates as compared with their Caucasian counterparts.  相似文献   
10.
Polycystic ovary syndrome (PCOS), insulin resistance and overall mortality due to diabetes and coronary artery disease are higher in South Asians than in Caucasians. Aims: We compared the prevalence of the C677T and A1298C single nucleotide polymorphisms in the methylenetetrahydrofolate reductase gene in South Asian and Caucasian women, its association with folate and homocysteine (Hcy) metabolism, and its relevance to future atherogenic events. Methods and results: 71 women were recruited for the study: South Asian PCOS (21) plus controls (9) and Caucasian PCOS (25) plus controls (16). Anthropometric and laboratory parameters were compared. South Asian PCOS women were significantly hyperandrogenic and exhibited a greater degree of insulin resistance. Caucasian PCOS women had higher plasma Hcy concentrations with a 1.9 times higher frequency of the T allele than the South Asian PCOS group. In the presence of this variant allele, plasma Hcy levels appear to be higher in both PCOS groups. The South Asians had a 1.8 times higher frequency of the C allele than the Caucasians; however, the overall frequency was comparable in the two PCOS groups. The frequency of homozygosity, i.e. TT677 and CC1298, was 7.2% and 4.9% in the Caucasians and 0% and 16.6% in the South Asian recruits, respectively. Dietary inadequacies in the South Asian women can influence their plasma folate and B12 concentrations resulting in hyperhomocysteinemia which, in combination with dyslipidaemia and insulin resistance, can lead to long-term atherogenic consequences. CONCLUSIONS: Current data suggests that the mechanisms of atherothrombosis have separate pathways in the two ethnic groups. Larger studies exploring the current theme need to be carried out in the PCOS groups to obtain adequate insight.  相似文献   
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