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1.
Abstract: We analyzed the expression of CEA, CA19-9, CA125, CA15-3 (DF3), PCNA and p53 immunohistochemically in 14 tissue specimens of mucosal cancers in adenoma, seven tubulovillous adenoma specimens, and 16 tubular adenoma specimens. The rates of positive staining for mucosal cancer in adenoma, tubulovillous adenoma and tubular adenoma specimens, respectively, were: for CEA: 100%, 85.7% and 75%; for CA19-9: 71.4%, 71.4% and 56.2%; for CA125:0%, 0% and 0%;for CA15-3 (DF3): 64.3 %, 0% and 0 %; for PCNA: 100%, 88.9% and 56.2%; and for p53: 35.7%, 0% and 0% . The results suggest that the expressions of CEA, CA19-9, CA15-3 (DF3), PCNA and p53 are related to colorectal tumorigenesis. None of the specimens studied showed staining for CA125, suggesting that CA125 is not involved in the early stages of colorectal carcinogenesis. There was no significant difference in the rates of positive staining for CEA and CA19-9 among mucosal cancer in adenoma, tubular adenoma and tubulovillous adenoma specimens. However, the rates of positive staining for PCNA and p53 were significantly higher in mucosal cancer in adenoma specimens than for tubular adenoma specimens (p<0.05), and the rate of CA15-3 (DF3) positive staining was significantly higher for mucosal cancer in adenoma than for tubulovillous adenoma (p<0.01) and tubular adenoma (p< 0.001) specimens. Therefore, the CA15-3 (DF3) antigen is an immunohistochemical marker for colorectal carcinomas. The present results suggest that CA15-3 (DF3), PCNA and p53 play important roles in the genesis of colorectal adenomas. 相似文献
2.
Ronald G. Pratt Jie Zheng Brent K. Stewart Yoseph Shiferaw Anthony J. McGoron Ranasinghage C. Samaratunga Stephen R. Thomas 《Magnetic resonance in medicine》1997,37(2):307-313
A limited flip angle gradient-echo 3D volume acquisition imaging protocol for mapping partial pressure of oxygen (pO2) in perfluorocarbon compounds (PFCs) at low field (0.14 T) is presented. The pO2 measurement method is based on the paramagnetic effect of dissolved molecular oxygen (O2) which reduces the PFC 19F T1? Specific objectives related to imaging of PFCs through use of the protocol include improved image signal-to-noise characteristics and elimination of 19F chemical shift artifacts. A parametric Wiener deconvolution filtering algorithm is used for suppression of 19F chemical shift artifacts. Application of the protocol is illustrated in a series of calculated pO2 maps of a gas equilibrated, multi-chamber phantom containing perfluorotributylamine (FC-43). The utility of the protocol is demonstrated in vivo through images of a commercially available perfluorocarbon based blood substitute emulsion containing FC-43 sequestered in the liver and spleen of a rat. 相似文献
3.
4.
Robert S. Mathias 《Pediatric nephrology (Berlin, Germany)》1997,11(3):355-357
. This is a report of unexplained anemia that persisted for 4 months in an adolescent renal transplant patient receiving immunosuppression
that included prednisone, tacrolimus, and mycophenolate mofetil. This patient required monthly blood transfusions for fatigue,
palpitations, and hematocrit levels between 15% and 17%. In addition, his posttransplant course was notable for the development
of insulin-dependent diabetes mellitus. While receiving low-dose prednisone, he was switched from tacrolimus to cyclosporin
and tapered off insulin injections over the next 2 months. At 4.5 months post-transplantation, further diagnostic evaluation
was suggestive of parvovirus B19 infection as the cause for our patient’s chronic anemia. After testing negative for serum-specific
parvovirus B19 IgM and IgG antibodies, parvovirus B19 infection was detected in blood by the polymerase chain reaction. Treatment
with intravenous immunoglobulin (1 g/kg per day × 2 days) resulted in normalization of both his reticulocyte count and hematocrit
within 6 weeks. At 4 months after receiving the immunoglobulin infusion, he has maintained a normal hematocrit level and stable
renal function without requiring further blood transfusions.
Received August 23, 1996; received in revised form and accepted November 20, 1996 相似文献
5.
《Movement disorders》2003,18(11):1240-1249
The identification of disease genes using family‐based approaches has provided important insights into the pathogenesis of Parkinson's disease (PD) demonstrating the importance of genetic studies on monogenic forms of the disease. We studied a large Cuban family with typical, late‐onset PD and probable autosomal dominant inheritance. Mean age at onset was 61.2 years (±12.53, 45–76). Other phenotypes such as essential tremor and atypical parkinsonism were observed in this family. We carried out a genome‐wide scan and linkage analyses. The genetic data were analyzed using a conservative model in which only patients with clinically definite or likely PD were considered affected, other phenotypes were regarded as “unknown.” Multipoint analyses yielded a maximum LOD of 2.26 between markers D19S221 and D19S840. Haplotype analysis showed a region on chromosome 19 shared by six of seven PD patients. The essential tremor phenotype and the atypical parkinsonism do not segregate with this haplotype, suggesting a different etiology. Our findings suggest the presence of a novel locus for PD on chromosome 19p13.3–q12. We propose that an oligogenic model with moderate contribution of two or three genes rather than a “pure” monogenic model might explain better the wide range in age at onset, the reduced penetrance and the phenotypical variability observed in PD families. © 2003 Movement Disorder Society 相似文献
6.
Norio Niikawa 《Journal of human genetics》1996,41(4):351-361
Summary Genomic imprinting is a biological phenomenon determined by an evolutionally acquired, underlying system that may control harmonious development and growth in mammals. It is also relevant to some genetic disorders in man. In this article, lines of biological evidence of imprinting, characteristics of the mouse and human imprinted genes, and findings and mechanisms on the occurrence of several human imprinting disorders are reviewed. 相似文献
7.
8.
建立人微小病毒B19的PCR检测方法 总被引:1,自引:0,他引:1
人微小病毒B19是微小病毒科中唯一能感染人的病毒。能够提供B19抗原的病毒体外培养系统尚未建成,因此限制了血清学实验的开发和普及。为此作者建立起B19病毒的PCR检测方法。设计引物在表达外壳蛋白VP1基因区,扩增长度为400bp。 相似文献
9.
Real-time quantitative RT-PCR and detection of tumour cell dissemination in breast cancer patients: plasmid versus cell line dilutions. 总被引:2,自引:0,他引:2
10.
Tau proteins are encoded by a single gene which is regulated by a unique promoter. The proximal 196 base pairs of the tau 5′ flanking region confers tau protein with neuronal specific expression and nerve growth factor inducibility. We tested tau promoter activity in neuronally differentiated embryonal carcinoma cells, the P19 mouse blastoderm cell line. In these experiments, we examined the temporal expression pattern of the tau promoter and compared it to other viral and cellular promoters. Tau promoter activity increases significantly with differentiation, specifically during neurite initiation. In addition, tau promoter activity in neuronally differentiated P19 cells was significantly greater than all five of the other neuronal or non neuronal promoters tested. All other promoters displayed low levels of promoter activity throughout retinoic acid induced neuronal differentiation of P19 cells. Taken together, our results suggest that the tau promoter is a good choice for ectopic expression of exogenous genes in P19 cells, which serves as a differentiating neuronal model system. 相似文献