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21.
Appearance of PIVKA-II (protein induced by vitamin K absence-II) in serum is a biochemical sign of insufficient vitamin K-dependent carboxylation of prothrombin. Plasma concentrations of PIVKA-II and vitamin K1 were determined in 24 children with cystic fibrosis. Eight were supplemented with vitamin K1. The purpose of the study was to determine the occurrence of vitamin K deficiency in cystic fibrosis and to evaluate the effect of vitamin K supplementation. PIVKA-II was detectable in only one unsupplemented child. In this patient, the concentration of vitamin K1 was below the limit of detection of 60 ng/l. Vitamin K1 levels in the other unsupplemented children were normal (mean 476 ng/l = 1 mmol/l). The supplemented patients showed extremely high levels of vitamin K1 (mean 22445 ng/l = 50 nmol/l). In conclusion, vitamin K deficiency occurs infrequently in cystic fibrosis. Checking the coagulation system is advised, but routine vitamin K supplementation is not recommended. If additional vitamin K is needed, the starting dose should not exceed 1 mg daily.  相似文献   
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A dermold cyst, arising from the posterior aspects of the prostate and seminal vesicles, and extending into the pelvis to masquerade as a full bladder, must be exceedingly rare. Ultrasound, computed tomography and especially magnetic resonance imaging (MRI) proved to be invaluable in making the diagnosis, and MRI in particular was very useful in providing an anatomical road map for surgery.  相似文献   
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The aetiology of 197 girls and 16 boys presenting with sexual precocity was reviewed. Ninety one girls and four boys had central precocious puberty (M:F 23:1); a cause was identified in all the boys but in only six girls. All boys with precocious puberty need detailed investigation; in girls investigation should be based on clinical findings, particularly the consonance of puberty.  相似文献   
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Thymic cysts in mediastinal Hodgkin disease   总被引:3,自引:0,他引:3  
Three cases of proved thymic cysts associated with mediastinal Hodgkin disease are presented. Two illustrate regression of lymphoma with chemotherapy but persistence of thymic cysts. The third case demonstrates a thymic cyst in untreated Hodgkin disease. These cases suggest that such cysts are probably neither coincidental with nor a consequence of therapy but are probably related to initial thymic involvement by Hodgkin disease.  相似文献   
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Objective  The performance of colposcopy provided in a screening study in five African countries was evaluated.
Design  Cross-sectional study.
Setting  Burkina Faso, Congo Brazzaville, Guinea Conakry, Mali and Niger.
Population  Women aged 25–59 years.
Methods  A total of 29 294 women participated in a cervical screening study in the five study sites, and newly trained local doctors performed colposcopy and directed biopsies as indicated. Using meta-analytical tools, four measures of colposcopy performance at different thresholds of colposcopic abnormalities were assessed. Sources of heterogeneity were also assessed.
Main outcome measures  Proportions of women receiving biopsies, adequate biopsies and women diagnosed with cervical intraepithelial neoplasia (CIN).
Results  Among 28 553 women with satisfactory colposcopy, 3101 had a colposcopic diagnosis of probable low-grade or worse lesions and 1128 probable high-grade or worse lesions. Overall, the measures that reached the set standards were proportion of biopsy taken at colposcopy threshold of probable high-grade or worse lesions (95%, 95% CI 90–100%) and proportion of adequate biopsy samples. The set standards were not met for the proportions of women diagnosed with CIN at different colposcopic abnormality thresholds. Detection of CIN2 or worse lesions increased with increasing colposcopic abnormality.
Conclusions  The performance of colposcopy in some of the African sites studied was comparable to that previously observed in other studies. With appropriate training, monitoring, continuing practice and quality assurance, adequate standards of colposcopy can be attained in sub-Saharan Africa.  相似文献   
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目的:建立家猪胸腰段脊髓火器贯通伤模型和改良Allen's打击伤后全瘫模型,观察伤后促凋亡基因p53基因的早期表达。方法:实验于2005-05/08在解放军第一七五医院实验室完成。取健康雄性家猪20只,单纯随机分为3组:①火器伤组:9只,在全麻状态下制作胸腰段(L1~L2)脊髓火器伤模型,分为伤后1,3,6h3个时间处死。②打击伤组:9只,L1节段脊髓行改良Allen’s打击,致伤力为500g·cm,处死时间同前。③空白对照组:2只,只麻醉,不造模,伤后6h处死。伤后不同时间点(伤后1,3,6h)和不同节段(伤点、近伤点、中伤点及远伤点)取材,采用SP法进行P53蛋白免疫组化染色,用TJTY-300型全自动图像分析仪测量P53免疫组织化学染色阳性物质吸光度。结果:经补充后20只猪进入结果分析。①脊髓损伤后3h打击伤组伤点,火器伤组近伤段脊髓P53蛋白的表达高于空白对照组(P<0.001),随着时间推移,打击伤组和火器伤组P53蛋白的表达呈升高趋势(P<0.001),且火器伤组要高于打击伤组(P<0.0001)。②在脊髓损伤后6h,打击伤组仅在伤点和近伤段P53蛋白的表达高于空白对照组(5.57±0.82,3.21±0.43,P<0.05),而火器伤组近伤段、中伤段及远段伤均高于空白对照组(6.46±0.66,4.27±0.39,1.16±0.17,P<0.05)。结论:①细胞凋亡基因p53在脊髓损伤中的表达有一定的时空性,在脊髓损伤后3h出现P53蛋白表达量的增加。②脊髓火器伤的波及范围较打击伤更为广泛。  相似文献   
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目的:探讨颈椎椎后肌肉组织Na -K -ATP酶活性变化与颈椎病的关系。资料来源:应用计算机检索PubMed1988-01/2004-12相关骨骼肌损伤与肌组织Na -K -ATP酶关系的文献,检索词“Na -K pump,Na -K -ATPase,muscle”,限定文献语言种类为English。同时计算机检索CNKI1990-01/2005-12相关Na -K -ATP酶与骨骼肌损伤的关系及颈椎病发病病因的文献,检索词“Na -K -ATP酶,骨骼肌,颈椎病病因”,限定文献语言种类为中文。资料选择:对资料进行初审,选取包括Na -K -ATP酶与肌组织损伤关系的文献,开始查找全文。纳入标准:Na -K -ATP酶活性变化与骨骼肌损伤密切相关的文献研究。排除标准:重复研究,Meta分析类文章。资料提炼:共检索到939篇关于Na -K -ATP酶与骨骼肌损伤相关方面的文献,最终纳入20篇符合标准的文献。资料综合:众多研究表明,Na 、K 与骨骼肌的兴奋、收缩、疲劳有密切关系,而Na -K -ATP酶又是调节细胞内外Na 、K 浓度必不可少的高分子蛋白,也就是说,骨骼肌一系列活动均离不开Na -K -ATP酶,Na -K -ATP酶活性变化与骨骼肌损伤是相互影响的。而强迫屈颈体位作为颈椎病发病的危险因素之一,可使颈椎椎后肌肉Na -K -ATP酶活性降低,酶活性降低致使肌细胞损伤,并最终导致骨骼肌损伤而发病。结论:以颈椎椎后肌肉酶活性的变化来阐释中医药对颈椎病确切疗效的相关研究未见,这有待于进一步研究,以充分展示中医药在颈椎病等相关疾病中的治疗优势。  相似文献   
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