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Ganti  SR; Antunes  JL; Louis  KM; Hilal  SK 《Radiology》1981,138(2):385
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P53 gene mutations in acute myeloid leukemia with 17p monosomy   总被引:4,自引:2,他引:4  
We looked for mutations of exons 5 to 8 of the P53 gene in 10 patients with acute myeloid leukemia (AML) and 17p monosomy, and 36 patients with AML and no cytogenetic abnormalities of 17p. DNA was analyzed by polymerase chain reaction, single-strand conformation polymorphism analysis, and nucleotide sequencing. Four of the 10 patients with 17p monosomy showed point mutation, single-nucleotide deletion, or insertion in exons 7 or 8. By contrast, only 1 of the 36 patients with AML and no cytogenetic abnormalities of 17p showed a mutation of the P53 gene in exons 5 to 8 (P less than .01). These results suggest that alterations of the P53 gene may have a role in leukemogenesis in some cases of AML. The fact that P53 gene mutations occurred more often in patients with 17p monosomy seems to support the "recessive" model of tumor suppressive activity of the P53 gene rather than the "dominant" model, in which alteration of only one allele is sufficient for the development of malignancy.  相似文献   
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Summary Secondary ion emission microanalysis is a new method of physical analysis recently applied in biology. The apparatus required (CAMECA SMI 300) enables pictures to be taken of the distribution of certain elements, with a space resolution of the order of 1 m. Concentrations below 1 p.p.m. are perceptible for most elements.The present results are the first obtained for human skin sections. Investigation of the natural elements of normal skin reveals no particular accumulation. Elements foreign to the skin are easy to detect. We show here the distribution in the epidermis of clinical antiseptics applied locally.This method has two advantages compared to X-ray microanalysis. It is more sensitive and allows analysis of even the lightes elements. However, its use in skin penetration studies is limited because it does not permit quantitative analysis and serious interference problems may occur.This work was supported by a grant from the INSERM (A.T.P. 677899 — Contrat No. 14)  相似文献   
86.
20世纪60年代中期,冷沉淀作为浓集Ⅷ因子被引入,主要用于治疗先天性Ⅷ因子缺乏,而后又被证实治疗血管性血友病和低纤维蛋白原血症有效.现在最常用于获得性低纤维蛋白原血症和大出血患者补充纤维蛋白原.实际上,其组成成分从来没有弄清楚过,也没有设计出合理的临床研究来确定其临床疗效.本文综述自1964年报道冷沉淀以来的文献,希望读者能了解冷沉淀的历史和早期的一些研究热点,从而激发读者进一步认识冷沉淀.  相似文献   
87.

Background  

Breast cancer management has improved dramatically in the past three decades and as a result, a population of working age women is breast cancer survivor. Interventions for breast cancer survivors have shown improvements in quality of life and in physical and psychological states. In contrast, efforts aimed at stimulating re-employment and return-to-work interventions for breast cancer survivors have not kept pace. The objective of this review was to study the effects and characteristics of intervention studies on breast cancer survivors in which the outcome was return to work.  相似文献   
88.
Objective: To determine the immunity to hepatitis B, poliomyelitis and measles in fully vaccinated Aboriginal and Torres Strait Island children in north Queensland.
Methodology: A cross-sectional survey of immunity in a sample of children; 101 fully vaccinated Aboriginal and Torres Strait Island children, with a median age of 24.5 months, from 10 communities in North Queensland participated in this study. The main outcome measures were the prevalence of adequate antibody levels against hepatitis B, poliomyelitis and measles.
Results: Only 54% (95% Cl 44–63%) of the children had adequate immunity (10 m iu/mL) to hepatitis B, and one child had been infected despite vaccination. Although all the children (95% Cl 96–100%) had adequate immunity (i.e. neutralizing antibodies at a dilution of 1:8) to poliovirus 2, only 93% (95% Cl 86–96%) and 60% (95% Cl 50–69%) had adequate immunity to polioviruses 1 and 3, respectively. Nearly all (96%; 95% Cl 90–98%) of the children had adequate immunity (i.e. detectable IgG antibody) to measles.
Conclusions: Although a relatively low proportion of the children had adequate antibody levels against hepatitis B the clinical significance of this observation is uncertain. Further studies are needed to determine whether fully vaccinated Torres Strait Island children have been adequately protected and whether they require a booster dose of hepatitis B vaccine. A substantial proportion of fully vaccinated Aboriginal and Torres Strait Island children are inadequately protected against poliomyelitis, and therefore any such child with acute flaccid paralysis should be investigated fully for poliomyelitis. Vaccinated Aboriginal and Torres Strait Island children are well protected against measles, as are other Australian children.  相似文献   
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