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981.
The Swedish childhood diabetes study — a multivariate analysis of risk determinants for diabetes in different age groups 总被引:3,自引:1,他引:2
Summary In a nationwide incident case-referent study stepwise univariate analysis has revealed several risk determinants for childhood diabetes mellitus. In a multivariate analysis we have determined the set of risk determinants that would independently predict childhood Type 1 (insulin-dependent) diabetes. Possible interactions between the risk determinants and differences in risk profiles with different ages at onset were also examined. Reported familial insulin-treated and non-insulin-treated diabetes were significant risk factors in all age groups, as was also a low frequency of milk intake. The frequency of infections and a high intake of foods rich in nitrosamine tended to interact (OR 11.8, p=0.053) indicating a synergistic effect. A Cox regression analysis revealed that stressful life events during the last year was the only variable that tended to affect the age at onset (p=0.055). This indicated that psychological stress may rather precipitate than induce Type 1 diabetes. A short breast-feeding duration (OR=3.81), and an increased body height (OR=3.82) contributed significantly to the predictive model in only the youngest age group (0–4 years). An increased frequency of infections in the year preceding onset (OR=2.15) and no vaccination against measles (OR=3.33) contributed significantly to the model only in the age group 5–9 years. Various nutrients had different impacts on the risk of developing Type 1 diabetes in different age groups. It is concluded that in the genetically susceptible child, risk factors which are associated with eating habits, frequency of infections, vaccination status, growth pattern and severe psychological stress affect the risk of developing diabetes independently of each other. The set of risk determinants varies with the age at onset. A high frequency of infections and a high frequency of nitrosamine-rich food intake seem to have a synergistic effect on the risk of developing diabetes in childhood. 相似文献
982.
慢性乙型肝炎表面抗原携带者前S1基因的高度异质性 总被引:1,自引:0,他引:1
应用半巢式聚合酶链式反应(PCR)从一例慢性HBsAg携带者血清中扩增出HBV前S1基因,将其克隆于噬菌体M13mp19中进行序列分析。结果发现:与同源性最好的HBVadr野生林相比,所测的10个克隆均有替代和插入突变,9个克隆有缺失突变,10个克隆的核苷酸变异率为5.0%-17.0%,氨基酸的变异率为13.0-60.0%;10个克隆之间的核苷酸变异率为2.3%-24.3%,氨基酸的变异率为14. 相似文献
983.
同种肾组织移植治疗慢性肾功能衰竭性贫血的实验研究 总被引:4,自引:0,他引:4
以Wistar雄性大鼠为受体,建立慢性肾功能衰竭动物模型,将鼠婴肾组织声多点植入受体双侧后肢皮下和筋膜下。结果表明,30天后移植物的体积由1mm^3增至4mm^3大小,表面血管网丰富;光镜下见肾小球、肾小管结构正常。促红细胞生成素(EPO)着色颗粒主要分布在肾小球区,移植组着色程度明显增高。血红蛋白和4促红细胞生成素随移植的时间延长而逐渐升高,实验结果提示,此方法有可能为治疗慢性肾功能衰竭性贫血提 相似文献
984.
目的:探讨儿童甲亢患者糖代谢紊乱的特点。方法:用SUPER GLUCOCARD^TM血糖仪和放射免疫方法检测29例甲亢患儿餐前、餐后60min、120min血糖和餐前、餐后60min胰岛素、C肽、胰高糖素、皮质醇及T3、T4、TSH、TGA、TMA(其中10例糖耐量减低为甲亢1组,另19例糖耐量正常为甲亢2组),并与20例健康儿童进行比较。结果:(1)34.5%甲亢患儿出现糖代谢紊乱,病程大于1年和小于1年糖代谢紊乱发生率为50%,9%(P<0.05)。(2)甲亢1组餐后60min胰岛素、胰岛素/血糖、胰岛素/胰高糖素显著升高(P<0.05)。结论:甲亢儿童存在糖代谢紊乱现象,表现为葡萄糖耐量减低和胰岛素拮抗,其发生与病程有关,病程较长,发生率较高。糖代谢紊乱可能与自身免疫、胰岛β细胞功能受损及胰岛素拮抗有关。 相似文献
985.
E. V. Borisova D. Yu. Rusakov S. K. Sudakov 《Bulletin of experimental biology and medicine》1992,114(3):1328-1332
986.
冠心病中医辨证与载脂蛋白关系的初步研究 总被引:14,自引:0,他引:14
对96例各种类型冠心病患者进行中医辨证分型,检测其血清载脂蛋白AⅠ及B100(apoAⅠ及apoB100),并设立对照组。结果显示各证型冠心病患者的apoAⅠ,apoB100及apoB1/apoAⅠ均有不同程度的改变。在标实证中以痰浊型改变最为明显,其apoAⅠ显著降低,apoB100及apoB100/apoAⅠ显著升高。在本虚证型中以肾虚型改变最为明显、其apoAⅠ显著降低。apoB100/apoAⅠ显著升高。这种各证型间的差异无疑对冠心病的中医辨证客观化有一定意义,值得进一步验证和探讨。 相似文献
987.
Takuo Fujita Masaaki Fukase Takao Shimada Hironosuke Yamamoto 《Journal of bone and mineral metabolism》1992,10(1):37-40
In addition to estrogen widely used all over the world for the prevention of postmenopausal osteoporosis, calcitonin and vitamin
D derivatives are commonly employed to treat established osteoporosis at higher age in Japan. In order to critically assess
the usefulness of vitamin D derivatives and calcitonin alone or in combination on the advancement of vertebral deformity at
higher age, 32 osteoporotic patients with vertebral deformity with the mean age of 79 were randomly divided into 4 groups
with indistinguishable age and severity of the vertebral deformity. Group 1 served as the control without specific medications
for osteoporosis. Group 2 was treated with 10 units elcatonin (eel calcitonin derivative) injected intramuscularly twice a
week. Group 3 was given 0.75 to 1.5μg/day 1α (OH) vitamin D3 orally. Group 4 was given a combination of treatments used in Groups 2 and 3.
In the lateral X-ray film of the spine taken prior to the test and every 6 months thereafter, the shape of the vertebral body
T8 through L4 was monitored by measuring the anterior, central and posterior heights. Decrease of the vertebral height ratio; anterior
or middle height/posterior or adjacent intact posterior height, by more than 20% of the original value or from above to below
0.80 both appeared to be inhibited during administration of 1α (OH) vitamin D3. Such effect seems to be augmented by simultaneous administration of elcatonin. Actual decrease of vertebral height ratio
values and the per cent fall from the original value significantly less in Groups 3 and 4 than in Group 1. Development of
vertebral deformity assessed by the changes of the vertebral height thus appears to decrease during treatment with 1α (OH) vitamin D3 especially together with calcitonin in established osteoporosis. 相似文献
988.
David A Grimes J David Grimes Lem Racacho Kylie A Scoggan Fabin Han Betty Anne Schwarz John Woulfe Dennise Bulman 《Movement disorders》2002,17(6):1205-1212
The identification of rare, large families with Parkinson's disease (PD) has provided important clues that have contributed to our understanding of this complex disorder. We have identified a large French-Canadian kindred that spans five generations consisting of more than 90 individuals. A total of 65 individuals now have been examined, had venous blood drawn, and DNA extracted. Two-point and multipoint linkage analysis was performed to assess linkage to known PD genes or loci. Within the third and fourth generations of this family there are 10 living, plus 3 deceased members with well-documented levodopa responsive parkinsonism. Autopsy results on 1 member demonstrated the loss of pigmented neurons in the substantia nigra and the presence of alpha-synuclein positive Lewy bodies. Four of the PD patients have prominent postural and kinetic tremors that preceded their parkinsonism by up to 10 years. Two other individuals within the family have prominent isolated postural and kinetic tremors without parkinsonism. The alpha-synuclein(4q21.3-23), Parkin(6q25.2-27), PARK3 (2p13), PARK4, and ubiquitin carboxy terminal hydrolase-L1 (4p14-16.3) and PARK6 and PARK7 (1p35-36) loci were excluded in this kindred using closely linked markers. The clinical and pathological features of this family are consistent with the diagnosis of PD. This family further demonstrates the known genetic heterogeneity in PD and is large enough that a genome-wide screen has been undertaken in an effort to identify a novel PD gene. 相似文献
989.
Selective drop-out in successive in-vitro fertilization attempts: the pendulum danger. 总被引:2,自引:2,他引:0
G Haan R E Bernardus H M Hollanders B A Leerentveld F M Prak N Naaktgeboren 《Human reproduction (Oxford, England)》1991,6(7):939-943
Success rates from in-vitro fertilization (IVF) in the long term are dependent on selection procedures with regard to continuation into further IVF episodes. Publications on success rates in successive episodes will give incentives to adapt selection criteria, but if these publications do not deal explicitly with patient selection, the adaptations might change their direction every time: the pendulum danger. 相似文献
990.
大鼠肝小肠联合移植模型的建立 总被引:1,自引:0,他引:1
孙晓毅 《中华器官移植杂志》1997,18(4):194-195
本文报告一种封闭群大鼠进行的肝小肠联合移植模型。术中供体肝与小肠整块游离和灌注,分开切取。供肝原位、供肠异位移植于受体大鼠。主要血管用Kamada袖套法吻合,正式实验21次,3天以上存活率为43%。结果表明:减少手术时间和简化操作技术是提高成功率的关键因素和基本原则。 相似文献