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71.
Across populations of children, Helicobacter pylori prevalence ranges from under 10% to over 80%. Low prevalence occurs in the U.S., Canada, and northern and western Europe; high prevalence occurs in India, Africa, Latin America, and eastern Europe. Risk factors include socioeconomic status, household crowding, ethnicity, migration from high prevalence regions, and infection status of family members. H. pylori infection is not associated with specific symptoms in children; however, it is consistently associated with antral gastritis, although its clinical significance is unclear. Duodenal ulcers associated with H. pylori are seldom seen in children under 10 years of age. H. pylori-infected children demonstrate a chronic, macrophagic, and monocytic inflammatory cell infiltrate and a lack of neutrophils, as compared with the response observed in adults. The effect of H. pylori infection on acid secretion in children remains poorly defined. The events that occur during H. pylori colonization in children should be studied more thoroughly and should include urease activity, motility, chemotaxis, adherence, and downregulation of the host response. The importance of virulence determinants described as relevant for disease during H. pylori infection has not been extensively studied in children. Highly sensitive and specific methods for the detection of H. pylori in children are needed, especially in younger pediatric populations in which colonization is in its early phases. Criteria for the use of eradication treatment in H. pylori-infected children need to be established. Multicenter pediatric studies should focus on the identification of risk factors, which can be used as prognostic indicators for the development of gastroduodenal disease later in life.  相似文献   
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The clinical presentation and evolution, neuropathological findings, and genotyping of three members of a Spanish family affected with fatal familial insomnia are reported. The mother and two of her offspring developed a rapidly evolving disease with insomnia and behavioural disorders as the initial symptoms and died between 5 and 10 months after the onset of the illness. Frontal brain biopsy in the mother disclosed only non-significant spongiosis, and full neuropathological examination of her offspring showed thalamic and olivary degeneration with isolated focal cortical spongiosis. Genetic examination could only be performed in the contemporary patients and both harboured the prion protein (PrP) 178Asn mutation and homozygous 129 Met/Met genotype.  相似文献   
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The localization of nitrergic cells and fibers and cholinergic cells has been analyzed in the spinal cord of the anuran amphibian Rana perezi. Histochemistry for nicotinamide adenine dinucleotide phosphate-diaphorase and nitric oxide synthase immunohistochemistry revealed a concurrent pattern of labeled structures. A large population of nitrergic spinal neurons was found from the level of the obex to the filum terminale. They are abundant in the dorsal horn and intermediate gray matter, but also occur in territories of the ventral horn and, only occasionally, in somatic motoneurons. Numerous nitrergic fibers were present in the spinal white matter, particularly in the dorsal and dorsolateral funiculi. A special arrangement of nitrergic axons is present in Lissauer's tract, where a collateral system is formed. Cholinergic cells, revealed by choline acetyltransferase immunohistochemistry, were observed throughout the spinal cord. The somatic motoneurons were the most conspicuously immunoreactive cells. A large population of cholinergic cells forms a discontinuous column in the intermediate gray, from the third spinal segment to lumbar segments. These cells were organized in a medially located or intercalated cell group, and a laterally located intermediolateral group. Numerous scattered cholinergic cells were present in the central zone of the ventral horn and were absent in the dorsal horn. Double-labeling experiments revealed a high degree of codistribution of nitrergic and cholinergic cells, mainly in the intermediate gray, but colocalization of both markers in the same neurons was not found. This result contrasts with the situation found in mammals and raises the question of whether coexpression of both substances was acquired in spinal cord neurons through evolution only in amniotes or, even, only in mammals.  相似文献   
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HPLC法测定紫茉莉根中葫芦巴碱的含量   总被引:1,自引:0,他引:1  
目的测定紫茉莉根中葫芦巴碱的含量.方法采用 HPLC法,色谱柱:Inertsil NH2Columns(250× 4.6 mm,5 μ m,迪马公司);流动相:乙腈-水(80:20);流速:0.8 mL· min-1;检测波长:265 nm;柱温:30 ℃.结果葫芦巴碱在 0.1872~ 0.9360 μ g之间与峰面积呈良好线性关系,r=0.9996;葫芦巴碱的平均回收率为 99.6 %,RSD=1.76%(n=6).结论该方法分离效果好,简便、准确,可用于紫茉莉根的初步质量控制.  相似文献   
80.
为探讨肺癌脊柱转移放射治疗的时间剂量分割方法及其疗效,将肺癌脊柱转移64例患者随机分为治疗组和对照组,治疗组每次3Gy,每周5次,共30Gy;对照组每次2Gy,每周5次,共50Gy;两组均使用6mVX线照射.分别比较疼痛缓解率、止痛起效时间、及脊髓压迫缓解率.结果显示治疗组和对照组的疼痛缓解率分别为87.5%和81.3%,无显著性差异(P>0.05);平均止痛起效时间分别为8±2.2天和15±3.2天,差异性显著(P<0.01);脊髓压迫缓解率分别为85.0%和81.8%,无显著性差异(P>0.05).结果表明放射治疗肺癌脊柱转移疗效好,起效快,建议使用30Gy/10f/2W的时间剂量分割模式.  相似文献   
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