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1.
A new range of stand magnifiers has been released by the COIL company in the United Kingdom. Examination of these magnifiers reveals that they fail to deliver the rated magnifications labelled prominently on the appliances, as a result of the manufacturer's conformance with the requirements of the German DIN standard and the use of back vertex power (F'v) rather than equivalent dioptric power (Fm) of the magnifier. In this study we provide information on the optometric parameters of these new stand magnifiers that will assist the more accurate specification of improvements in vision expected from their use.  相似文献   
2.
A school microepidemic of tuberculosis.   总被引:1,自引:1,他引:0       下载免费PDF全文
C P Bredin  M Godfrey    J McKiernan 《Thorax》1991,46(12):922-923
BACKGROUND: Microepidemics of tuberculosis continue to occur in countries with a low incidence of tuberculosis. METHODS AND RESULTS: A microepidemic of tuberculosis in a secondary school with 604 girls in Cork city, Ireland, in 1986 with follow up to 1990 is described. Neonatal BCG vaccination was discontinued in the city in December 1972 so most of the 342 pupils who had received BCG were aged 14 years or more. Six active cases and 75 tuberculin positive cases were found. Four of the six girls with active disease had had neonatal BCG. The 75 pupils with a positive (grade 3 or 4) Heaf test response were given chemoprophylaxis with rifampicin and isoniazid for six months; none had developed active tuberculosis four years later. The brother of the girl who was the probable index case, however, developed active tuberculosis in 1988 despite similar chemoprophylaxis. CONCLUSION: The episode highlights the fact that children who have had neonatal BCG can develop active tuberculosis as teenagers.  相似文献   
3.
The protein kinase C (PKC) family of genes encode serine/threonine kinases that regulate proliferation, apoptosis, cell survival and migration. Multiple isoforms of PKC have been described, one of which is PKCδ. Currently, it is unclear whether PKCδ is involved in promoting or inhibiting cancer formation/progression. The aim of this study was therefore to investigate the expression of PKCδ in human breast cancer and relate its levels to multiple parameters of tumour progression. Protein kinase Cδ expression at the mRNA level was measured using real-time PCR (n=208) and at protein level by both immunoblotting (n=94) and ELISA (n=98). Following immunoblotting, two proteins were identified, migrating with molecular masses of 78 and 160 kDa. The 78 kDa protein is likely to be the mature form of PKCδ but the identity of the 160 kDa form is unknown. Levels of both these proteins correlated weakly but significantly with PKCδ concentrations determined by ELISA (for the 78 kDa form, r=0.444, P<0.005, n=91 and for the 160 kDa form, r=0.237, P=0.023, n=91) and with PKCδ mRNA levels (for the 78 kDa form, r=0.351, P=0.001, n=94 and for the 160 kDa form, r=0.216, P=0.037, n=94). Protein kinase Cδ mRNA expression was significantly higher in oestrogen receptor (ER)-positive compared with ER-negative tumours (P=0.007, Mann–Whitney U-test). Increasing concentrations of PKCδ mRNA were associated with reduced overall patient survival (P=0.004). Our results are consistent with a role for PKCδ in breast cancer progression.  相似文献   
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There is a lack of evidence to determine if diet quality is associated with cognitive performance in older adults. Therefore, the aim of this study was to examine whether diet quality is associated with cognitive performance among older adults. A cross-sectional, secondary analysis of baseline data from the Hunter Community Study (HCS), comparing diet quality, measured using the Australian Recommended Food Score (ARFS), along with validated cognitive performance instruments the Audio Recorded Cognitive Screen (ARCS) and the Mini-Mental State Examination (MMSE) were undertaken in adults aged 55–85 years, living in Newcastle, NSW, Australia. Adjusted linear regression analyses showed that, compared with the lowest ARFS quintile, those in the highest quintile had an ARCS score 5.883 units greater (p < 0.001; R2 = 0.0098). Furthermore, when quintiles of ARFS score were tested against each ARCS sub-scale score, statistically significant associations were observed with the greatest effect for the Memory (β = 4.055; p = 0.001; R2 = 0.0065) and Attention (β = 4.136; p = 0.002; R2 = 0.0047) domains. No statistically significant associations were observed between quintiles of ARFS and MMSE score in the adjusted linear regression analyses. In conclusion, a positive association was observed between diet quality and cognitive performance within this sample of older Australian adults. Further investigation of the above association over time, when follow-up data becomes available, in longitudinal analysis is recommended.  相似文献   
6.
恶性肿瘤患者血清与尿液中一氧化氮含量测定   总被引:1,自引:1,他引:0  
0 引言一氧化氮(Nitric oxide,NO)是一种具有活跃生物化学性质的无机小分子. NO对许多肿瘤细胞和微生物有细胞毒性[1],为探讨NO与肿瘤的关系,我们检测了119例恶性肿瘤患者血清及尿液中的NO.  相似文献   
7.
Abstract: We report the first case of fatal anthrax meningoencephalitis in Hong Kong over the past 60 years. A 13 year-old boy presented with right lower quadrant pain, diarrhoea and progressive headache. Lumbar puncture yielded gram positive bacilli initially thought to be Bacillus cereus, a contaminant. He was treated with ampicillin and cefotaxime, but died 3 days after hospitalization. The organism isolated from blood and cerebrospinal fluid was later identified as Bacillus anthracis.  相似文献   
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头皮糠疹是常见病是多发病,临床表现为头皮红斑和脱屑,提示皮损部位表皮结构和功能异常,头皮角质层代谢紊乱,最近对头皮糠疹病因和病理的研究证实马拉色菌,皮脂分泌和个体敏感性是形成上述皮损的3个关键因素,硫氧吡啶锌(PTZ或ZPT)可以有效地杀灭马拉色菌,PTZ的颗粒大小和形状对其在头皮的生物利用度有明显的影响。此外,PTZ的抗菌效果有赖于其分子结构的完整性,在外用制剂中加入附加的游离锌,可以有效防止PTZ解离,从而提高其疗效。  相似文献   
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