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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
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Two cases of pediatric accidental ingestion of an acetonitrile-containing cosmetic are reported. One of the children, a 16-month-old boy, was found dead in bed the morning after ingesting the product. No therapy had been undertaken, as the product was mistakenly assumed to be an acetone-containing nail polish remover. The second child, a 2-year-old boy, experienced signs of severe cyanide poisoning, but survived with vigorous supportive care. Both children had blood cyanide levels in the potentially lethal range. The observed delayed onset of severe toxic reactions supports the proposed mechanism of acetonitrile conversion to inorganic cyanide via hepatic microsomal enzymes. Physicians and poison centers should be alerted to the existence of this highly toxic product, sold for removal of sculptured nails and likely to be confused with the less toxic acetone-containing nail polish removers. We urge regulatory agencies to reconsider the wisdom of marketing a cosmetic that poses such an extreme health hazard. 相似文献
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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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Gonzales AJ; Christensen JG; Preston RJ; Goldsworthy TL; Tlsty TD; Fox TR 《Carcinogenesis》1998,19(7):1173-1183
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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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目的比较5French(5F)及6French(6F)导引导管在经桡动脉冠状动脉介入治疗(TRI)患者中的安全性及有效性。方法共纳入2009年2月至2010年3月患者,收集相关资料录入数据库,包括患者基线临床资料、导引导管的尺寸、靶血管、靶病变的特点、手术的成功率、手术失败原因、经桡动脉冠状动脉介入治疗手术的成功率及失败原因、患者住院期间主要不良心血管事件率及术后桡动脉闭塞率。结果连续纳入患者共185例,接受195次经桡动脉冠状动脉介入治疗术,平均年龄(57±11)岁(33~81岁);其中54例患者纳入6F导引导管组,共进行56次手术,治疗89处病变;138例患者纳入5F导引导管组,共行146次手术,治疗231处病变。AHA B2/C型病变比例在两组间差异无统计学意义(5F组43.7%/29.0%比6F组46.1%/34.6%,P>0.05),但慢性闭塞性病变、分叉病变、钙化病变5F组显著少于6F组(5.6%比14.6%,P=0.005;23.4%比37.1%,P=0.012;9.5%比47.2%,P<0.001);组间的手术时间[(45±21)min比(46±19)min)]、手术X线曝光时间[(15±12)min比(16±13)min]、使用造影剂量[(140±45)ml比(156±56)ml]差异均无显著统计学意义(P>0.05),但是5F组造影剂用量有减少的趋势(P=0.066);组间住院时间[(1.40±1.26)d比(1.29±0.69)d]和手术成功率(95.2%比94.6%)也差异无统计学意义(P>0.05);5F组1例患者术后桡动脉闭塞,6F组无患者术后桡动脉闭塞(P=1.0),5F组1例发生卒中。结论经桡动脉冠状动脉介入治疗,即使是复杂及高危冠脉病变,5F导引导管有效、安全,手术成功率不低于常规使用的6F导引导管;换用5F导引导管进行冠状动脉介入治疗是一种有吸引力的选择。 相似文献
9.
Dziennis S; Van Etten RA; Pahl HL; Morris DL; Rothstein TL; Blosch CM; Perlmutter RM; Tenen DG 《Blood》1995,85(2):319-329
CD11b is the alpha chain of the Mac-1 integrin and is preferentially expressed in myeloid cells (neutrophils, monocytes, and macrophages). We have previously shown that the CD11b promoter directs cell-type- specific expression in myeloid lines using transient transfection assays. To confirm that these promoter sequences contain the proper regulatory elements for correct myeloid expression of CD11b in vivo, we have used the -1.7-kb human CD11b promoter to direct reporter gene expression in transgenic mice. Stable founder lines were generated with two different reporter genes, a Thy 1.1 surface marker and the Escherichia coli lacZ (beta-galactosidase) gene. Analysis of founders generated with each reporter demonstrated that the CD11b promoter was capable of driving high levels of transgene expression in murine macrophages for the lifetime of the animals. Similar to the endogenous gene, transgene expression was preferentially found in mature monocytes, macrophages, and neutrophils and not in myeloid precursors. These experiments indicate that the -1.7 CD11b promoter contains the regulatory elements sufficient for high-level macrophage expression. This promoter should be useful for targeting heterologous gene expression to mature myeloid cells. 相似文献
10.
Activation and expansion in culture with rIL-2 of peripheral blood (PB) and/or bone marrow (BM) specimens derived from children with ALL and ANLL, with active disease (AP) and in remission were studied (RP). Baseline NK cytolytic activity from AP was found to be depressed, whereas RP-derived cells had normal NK activity, as assayed against K562 targets. Culture in rIL-2 significantly enhanced the NK activity of both AP- and RP-derived cells and generated LAK activity, as assayed by 4-hour 51Cr release, against NK-resistant Raji cell line and against fresh, allogeneic, and autologous tumor cells. Lytic activity against fresh, cryopreserved leukemia blasts was of lower than that found against cell lines. In three patients higher lytic activity against autologous than against allogeneic blasts was demonstrated. Expansion in culture with rIL-2 varied from twofold to 120-fold. rIL-2 activation and expansion was better in RP than in AP. The predominant phenotype of activated cells, as determined by flow cytometry, was [mean % (SD)]: CD3- = 54 (12), CD8+ = 55 (17), and NKH1+ = 26 (7). The consistently high level of CD8+ cells was accompanied by very low levels of CD4+ cells: mean = 11% (14). Double-marker analysis showed mean of 33% (10) for CD3+/NKH1+ cells and mean = 32 (11) for CD8+/NKH1+ cells, implying that these populations were overlapping. Kinetics of expression of cell surface markers during 2 to 3 weeks in culture showed that CD8+ and NKH1+ enrichment occurred during the first week and lasted for up to 4 weeks, whereas CD4+ expression decreased after the second week. A significant decrease in the expression of IL-2 receptors (CD25) was observed from the second week of culture. This study shows the feasibility of in vitro generation of killer cells from PB and BM of pediatric leukemia patients. 相似文献