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91.
Chan  LC; Furley  AJ; Ford  AM; Yardumian  DA; Greaves  MF 《Blood》1986,67(2):533-536
A case of lymphoid blast crisis of Ph1-positive CGL is described in which the blast cells had an immature T cell phenotype, clonal rearrangement and expression of the T cell receptor beta gene, and a rearrangement of the breakpoint cluster region (bcr) on chromosome 22. This case therefore provides definite evidence for transformation involving a common myeloid-T lineage progenitor, penetrance of the Ph1 molecular alteration into the T cell lineage, and clonal selection in blast crisis at the level of a committed T lineage precursor.  相似文献   
92.
Ca2+-ionophore A23187-induced synthesis of the alkoxyether lipid platelet activating factor (PAF) by leukocytes from Zellweger patients was undetectable in two patients studied at 3 and 4 weeks of age, reduced in a third patient studied at 2 months of age, and in the low normal range in four patients studied between 4 months and 5 years of age. We have previously reported that plasmalogen-type phosphatidylethanolamine (PE) levels of erythrocytes are reduced in Zellweger patients up to 20 weeks of age, but normal in older patients. These levels were reduced in the three patients with abnormal PAF synthesis, and normal in the other four patients. The results suggest a close relationship between the age of the patients at sampling, and both the A23187-induced capacity of leukocytes to synthesize PAF and the plasmalogen PE levels in their erythrocytes.  相似文献   
93.
Two new human myeloma cell lines have been established from a 36-year- old woman with refractory IgG kappa multiple myeloma in whom bilateral malignant pleural effusions developed. The malignant plasma cells from each effusion were set up in a liquid culture using an L-15 medium containing catalase, glutathione, selenous acid, ascorbic acid, insulin, transferrin, additional glutamine hydrocortisone, and 2- mercaptoethanol and designated as M-3 medium. Two IgG kappa cell lines, LB -831 and LB-832, were established and proved to be Epstein-Barr virus negative using the internal repeat sequence DNA probe. Characteristic plasma cell morphology was evident by light and electron microscopy. Immunotyping revealed an IgG kappa , B1+, B2-, Ia (HLA- DR)+, CALLA+ phenotype for each cell line as well as for the original pleural fluid and bone marrow myeloma cells. The supernatants also contained IgG kappa, beta 2 microglobulin, and large amounts of osteoclast-activating factor (indicating bone-resorbing activity). Cytogenetic analysis of the LB-831 cell line revealed a nearly triploid highly abnormal karyotype with numerous clonal chromosomal abnormalities involving chromosomes 1, 3, 5, 7, 13, and 15; several structurally abnormal marker chromosomes; and a putative homogeneously staining region on chromosome 7p at band p22. Analysis of the LB-832 cell line revealed several additional clonal abnormalities. These additional cytogenetic changes suggest that in vivo sequential clonal evolution occurred in this patient. Therefore, two new but related cell lines have been established, which should prove useful for further biological studies.  相似文献   
94.
OBJECTIVE: To investigate the association between total plasma homocysteine concentration, C677T and A1298C polymorphisms in MTHFR gene and Alzheimer's disease (AD) development. METHOD: Forty-three patients with probable (63%) and possible (37%) AD and 50 non-demented controls were evaluated. Groups did not differ as to gender, age, scholar years, diabetes, alcohol and coffee intake and physical activity. Total plasma homocysteine (Hcy) levels were determined by HPLC and genotyping for MTHFR by PCR/RFLP. Mann-Whitney "U" test was used to compare quantitative variable, Fisher-Freeman-Halton test to compare genotypes and allele proportions and Chi-square test to other qualitative variables. RESULTS: AD patients presented higher total plasma Hcy levels than controls and the difference was statistically significant. No differences in the C677T and A1298C MTHFR polymorphisms distributions were found between patients and controls. Plasma homocysteine concentration did not change with MTHFR genotypes. CONCLUSION: Our data confirms the association between increased plasma Hcy concentration and AD and suggests that neither C677T nor A1298C MTHFR polymorphisms contributed to genetic susceptibility for AD in elderly individuals in the Northeast of Brazil.  相似文献   
95.
96.
Inositol has been cited as being essential for the growth of micro-organisms and animals. Its action rests mostly in the formation of a set of inositol-containing lipids, including phosphatidylinositol and its phosphorylated derivatives. To evaluate the functional responses coupled to the phosphoinositide metabolism in Trypanosoma cruzi we used myo-inositol and its six fluorinated analogues. Their uptake into epimastigotes was characterised using tritium-labeled myo-inositol and monodeoxyfluoro-myo-inositols. The analogues were tested for their ability to inhibit [3H]-myo-inositol incorporation into phosphoinositides and the proliferation of epimastigotes and amastigotes. The results showed differences between T. cruzi and mammalian systems in the responses to the fluorinated analogues. We found that the 3-, 5- and 6-fluoro analogues did not enter the cells but had an inhibitory effect on the incorporation of the radioactive inositol into lipids and on the amastigotes' and epimastigotes' replication. The most effective inhibitor, 1-D-6-deoxy-6-myo-inositol, had no effect on mammalian cell division. Received: 12 June 1998 / Accepted: 15 September 1998  相似文献   
97.
Objective : To determine the genotype of patients attending the cystic fibrosis clinic at John Hunter Hospital, Newcastle, Australia.
Methodology : Seventy-five of the 76 patients attending the clinic over a 6 month period had blood collected for genetic analysis of 17 of the cystic fibrosis (CF) gene mutations.
Results : Sixty-one per cent of the patients were homozygous for the ΔF508 mutation and all except one child had at least one ΔF508 mutation.
Discussion : Nearly 80% of the CF genes were the ΔF508 mutation. This prevalence suggests that the obligatory false negative rate of a newborn screening programme for CF based on a combination of immunoreactive trypsin and the ΔF508 gene may be as low as 4-5%.  相似文献   
98.
1病例报告女,26岁.因孕5 mo余,右腰腹部间断性疼痛3 d伴高烧,于2004-05-27急诊入本院泌尿外科.患者疼痛难忍,向右下腹放射,间歇性,无恶心呕吐,无尿急、尿频、尿痛,伴发热,体温最高可达40℃,既往无泌尿系患病史.查体: T 40℃,P 110次/min,BP 16/10 kPa,R 21次/min.痛苦面容,心肺正常,右肾区及右输尿管走行区扣击痛.  相似文献   
99.
Chan  FK  Ching  JY  Hung  LC  齐文安 《英国医学杂志》2005,8(6):372-373
问题:在有阿司匹林诱发溃疡出血史的患者中,用氯毗格雷预防溃疡出血复发,是否不次于小剂量阿司匹林加埃索美拉唑?[编者按]  相似文献   
100.
Holoprosencephaly (HPE) is the most common brain anomaly in humans, involving abnormal formation and septation of the developing central nervous system. Among the heterogeneous causes of HPE, mutations in the Sonic Hedgehog (SHH) gene have been shown to result in an autosomal dominant form of the disorder. Here we describe a total of five different mutations in the processing domain encoded by exon 3 of SHH in familial and sporadic HPE. This is the first instance in humans where SHH mutations in the domain responsible for autocatalytic cleavage and cholesterol modification of the N-terminal signaling domain of the protein have been observed.   相似文献   
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