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排序方式: 共有712条查询结果,搜索用时 15 毫秒
31.
Maternal origin of transferrin receptor positive cells in venous blood of pregnant women 总被引:1,自引:0,他引:1
Anna Slunga-Tallberg Wa'el El-Rifai Mauri Keinänen Kari Ylinen Tapio Kurki Katherine Klinger Olavi Ylikorkala Marcelo L. Larramendy Sakari Knuutila 《Clinical genetics》1996,49(4):196-199
We studied the origin of transferrin receptor (CD71) positive cells in blood from seven women pregnant with a male fetus in order to explore if fetal cells could be detected among them. We used a technique that allows direct chromosomal analysis by in situ hybridization on immunologically and morphologically classified cells. Enrichment was performed by magnetic activated cell sorting (miniMACS)® using an anti-CD71 monoclonal antibody. The cells were immunophenotyped by alkaline phosphatase anti-alkaline phosphatase immunostaining with the same antibody. The origin of the immunophenotyped cells was studied by in situ hybridization using an X cosmid Y repeat chromosome specific probe cocktail. CD71 positive cells were found in six of the seven women at the range of 4 to 43 in respective samples. Over 90% of the CD71 positive cells were nucleated erythrocytes. None of the detected positive cells were shown to be fetal. Thus, the use of transferrin receptor antigen alone in combination with the miniMACS® may not be sufficient for enrichment of fetal cells. 相似文献
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34.
Pia Alhopuro Auli Karhu Robert Winqvist Kati Waltering Tapio Visakorpi Lauri A Aaltonen 《BMC cancer》2008,8(1):263
Background
MYH11 (also known as SMMHC) encodes the smooth-muscle myosin heavy chain, which has a key role in smooth muscle contraction. Inversion at the MYH11 locus is one of the most frequent chromosomal aberrations found in acute myeloid leukemia. We have previously shown that MYH11 mutations occur in human colorectal cancer, and may also be associated with Peutz-Jeghers syndrome. The mutations found in human intestinal neoplasia result in unregulated proteins with constitutive motor activity, similar to the mutant myh11 underlying the zebrafish meltdown phenotype characterized by disrupted intestinal architecture. Recently, MYH1 and MYH9 have been identified as candidate breast cancer genes in a systematic analysis of the breast cancer genome. 相似文献35.
M M?ki M L L?hdeaho O H?llstr?m M Viander J K Visakorpi 《Archives of disease in childhood》1989,64(11):1604-1607
Altogether 38 postpubertal children with coeliac disease were rebiopsied. Mucosal abnormality in nine (24%) of them indicated poor adherence to the diet. Gluten challenge with a diet containing a normal amount of gluten was performed in those 29 patients with a normal mucosa. During challenge, rebiopsy was done when reticulin antibodies turned positive (mean 0.6 years, range 0.2-2.0) or at the end of the two year study. Histologically a clear relapse into coeliac disease was seen in all 23 patients who were positive for reticulin antibodies. At this time gliadin antibodies were positive in all but two. Sixteen (70%) of those who relapsed were completely asymptomatic. Three girls and one boy did not relapse within two years, indicating the possible recovery from coeliac disease to be 11%. All four had undergone gluten challenge earlier in childhood, after initial diagnosis and mucosal recovery, and this had resulted in mucosal relapse. To establish definite postpubertal recovery from coeliac disease in cases with normal mucosa at two years from challenge, further follow up studies of reticulin antibodies and later rebiopsy are needed. The reticulin antibody test seems to be suitable for prediction of mucosal relapse in coeliac disease. 相似文献
36.
A. Auvinen J. Isola T. Visakorpi T. Koivula S. Virtanen M. Hakama 《British journal of cancer》1994,70(2):293-296
Survival analysis of 144 histologically confirmed cases of colon carcinoma diagnosed in a 12 year period (1971-82) at the Tampere University Hospital was performed to test the hypothesis that p53 overexpression is associated with a poor clinical outcome. Immunohistochemical staining of paraffin-embedded sections using a polyclonal antibody CM-1 against p53 protein was performed to identify aberrant expression of the p53 tumour-suppressor gene. Sixty-nine per cent of the tumours (100/144) showed overexpression of the p53 protein. The prevalence of p53 overexpression was independent of age and sex of the patient and subsite of the tumour, but was slightly, although not statistically significantly, higher in advanced than in localised tumours. Overexpression was associated with a higher S-phase fraction. Some indication of a larger proportion of aneuploid tumours among those with overexpression was also observed, although this finding did not reach statistical significance. Significantly reduced patient survival for tumours with p53 overexpression was found. Patients with p53-overexpressing tumours had a corrected 5 year survival rate of 37% compared with 58% among patients whose tumours had normal expression of p53. The corresponding 10 year rates were 34% and 54%. In the multivariate analysis using a Cox model, the survival difference was independent of age and sex of the patient, as well as of subsite and stage of the tumour. Furthermore, the effect of p53 overexpression remained after controlling for flow cytometric parameters in an analysis of a subset of tumours. Thus, p53 overexpression appears to be a useful prognostic indicator in colon carcinoma. 相似文献
37.
Background
Our investigation sought to compare changes in sexual function following supracervical hysterectomy (SCH) and total abdominal hysterectomy (TAH). 相似文献38.
Varho TT Alajoki LE Posti KM Korhonen TT Renlund MG Nyman SR Sillanpää ML Aula PP 《Pediatric neurology》2002,26(4):267-273
Salla disease (MIM 269920) represents the mildest phenotype among recessively inherited lysosomal-free sialic acid storage disorders. Although the vast majority of Salla disease patients in Finland share the same founder mutation, R39C in the SLC17A5 gene, there still is a wide clinical variation among mentally retarded, ataxic patients. We evaluated neurologic and neurocognitive findings of Salla disease in a cross-sectional study of 41 Finnish patients who were 11 months to 63 years of age (median = 19.5 years). The phenotype of Salla disease could be classified into two main categories. The majority of patients (90%) had so-called conventional phenotype, including a subgroup of seven patients with relatively mild symptoms. All but two patients with conventional phenotype were homozygous for the Finnish founder mutation. Four severely disabled, profoundly mentally retarded patients, 15-28 years of age, clearly could be clinically delineated as a separate group, likely reflecting the underlying compound heterozygous genotype. A typical developmental pattern could be outlined in the conventional type of the disease, emphasizing a strong motor handicap in Salla disease. The cognitive profile consisted of better verbal ability, especially speech comprehension, compared with nonverbal functioning in all patients. Our results indicate a partial genotype-phenotype correlation, although factors other than the molecular background are also involved in the phenotypic manifestation of Salla disease. 相似文献
39.
Circulating enterolactone and prostate cancer risk: a Nordic nested case-control study 总被引:4,自引:0,他引:4
Stattin P Adlercreutz H Tenkanen L Jellum E Lumme S Hallmans G Harvei S Teppo L Stumpf K Luostarinen T Lehtinen M Dillner J Hakama M 《International journal of cancer. Journal international du cancer》2002,99(1):124-129
Enterolactone, a phytoestrogen belonging to the class of lignans, is produced by the intestinal microflora from precursors in plant foods and has been implicated in protection against cancer. We study the effect of enterolactone on the risk of a subsequent diagnosis of prostate cancer. We conducted a longitudinal, nested case-control study by linkage of 3 biobanks to the cancer registries in Finland, Norway and Sweden, respectively. Enterolactone concentrations were measured by time-resolved fluoroimmunoassay in serum from 794 men who had a diagnosis of prostate cancer at a mean follow-up time of 14.2 years after blood collection and among 2,550 control men matched within each cohort for age (+/-2 years), date of blood collection (+/-2 months) and county. The median enterolactone concentrations did not differ between case and control subjects in the full study group (8.4 nmol/L [25th-75th percentile = 4.5-15.0] vs. 8.5 nmol/L [25th-75th percentile = 4.3-15.9]), nor in the national groups. Odds ratios of prostate cancer risk estimated by conditional logistic regression for increasing concentrations of enterolactone in quartiles in the full study group were 1.00 (referent), 1.21 (95% confidence interval [CI] = 0.96-1.52), 1.16 (95% CI = 0.91-1.47) and 1.08 (95% CI = 0.83-1.39). The OR estimate for the highest vs. the lowest quartile of enterolactone in separate analyses of the Norwegian, Finnish and Swedish cohort was 1.21 (95% CI = 0.91-1.60), 1.02 (95% CI = 0.59-1.76) and 0.87 (95% CI = 0.45-1.67), respectively. No support for the hypothesis that high circulating enterolactone is protective against prostate cancer was found. 相似文献
40.
Maija Koljonen Kati S Hakala Tuula Ahtola-S?til? Leena Laitinen Risto Kostiainen Tapio Kotiaho Ann Marie Kaukonen Jouni Hirvonen 《European journal of pharmaceutics and biopharmaceutics》2006,64(3):379-387
The purpose of this study was to investigate the suitability and reliability of n-in-one approach using FDA suggested compounds for standardising Caco-2 permeability experiments. Special attention was paid to the evaluation of rank order correlation and mechanistic insights of compound permeability. Transport studies with antipyrine, metoprolol, ketoprofen, verapamil, hydrochlorothiazide, ranitidine, mannitol and fluorescein were performed in 12- and 24-well formats, as single compounds and in cocktails under iso-pH 7.4 and pH-gradient (pH 5.5 vs. 7.4) conditions. Compounds were quantified using n-in-one LC/MS/MS analysis. The cocktail-dosing proved to be a feasible method to determine the permeability of the Caco-2 cell line and to introduce external standards for permeability tests. Even though sink conditions were lost in cocktail experiments for highly permeable compounds, the rank order of compound permeability and the classification to low and high permeability compounds remained unchanged between single and cocktail studies and permeability values of 12- and 24-well formats were directly comparable. Under pH-gradient conditions the margin between high and low permeability compounds was narrower due to the lower permeability (higher fraction of ionisation) of basic molecules. Of the compounds studied, antipyrine, metoprolol, hydrochlorothiazide and mannitol are suitable for evaluation and standardisation purposes of passive permeability, while fluorescein would function as paracellular marker under iso-pH 7.4. As efflux activity may vary between cell batches, verapamil is a useful marker for P-glycoprotein. 相似文献