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排序方式: 共有5465条查询结果,搜索用时 15 毫秒
51.
Yamazaki K McGovern D Ragoussis J Paolucci M Butler H Jewell D Cardon L Takazoe M Tanaka T Ichimori T Saito S Sekine A Iida A Takahashi A Tsunoda T Lathrop M Nakamura Y 《Human molecular genetics》2005,14(22):3499-3506
The inflammatory bowel diseases (IBDs), Crohn's disease (CD) and ulcerative colitis, are chronic inflammatory disorders of the digestive tract. The pathogenesis of IBD is complicated, and it is widely accepted that immunologic, environmental and genetic components contribute to its etiology. To identify genetic susceptibility factors in CD, we performed a genome-wide association study in Japanese patients and controls using nearly 80,000 gene-based single nucleotide polymorphism (SNP) markers and investigated the haplotype structure of the candidate locus in Japanese and European patients. We identified highly significant associations (P = 1.71 x 10(-14) with odds ratio of 2.17) of SNPs and haplotypes within the TNFSF15 (the gene encoding tumor necrosis factor superfamily, member 15) genes in Japanese CD patients. The association was confirmed in the study of two European IBD cohorts. Interestingly, a core TNFSF15 haplotype showing association with increased risk to the disease was common in the two ethnic groups. Our results suggest that the genetic variations in the TNFSF15 gene contribute to the susceptibility to IBD in the Japanese and European populations. 相似文献
52.
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54.
Immunohistochemical characteristics of duodenal adenomas in familial adenomatous polyposis with special reference to cell kinetics 总被引:4,自引:0,他引:4
The duodenum is the second most frequent site of cancer in patients with familial adenomatous polyposis (FAP). The main objective of this study was to evaluate the cell kinetics in duodenal and ampullary adenomas in FAP. The endoscopic and biopsy findings of duodenal adenomas in 22 FAP subjects and 18 non-FAP subjects were compared. Adenomas in FAP included 15 ampullary adenomas and 17 nonampullary adenomas. The cell kinetics was evaluated by immunohistochemistry for Ki-67, p53, bcl-2, and cyclooxygenase 2 (COX2), and the apoptotic index (AI) as determined by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) method. Any correlations between the indices for cell kinetics and the endoscopic findings were identified. All 50 adenomas were histologically verified to be tubular adenoma with low-grade dysplasia. Neither the expression of Ki-67, p53, bcl-2, and COX2 nor the AI differed substantially between FAP and non-FAP subjects. In patients with FAP, duodenal adenoma tended to have a higher Ki-67-labeling index than the ampullary adenoma (54.3 +/- 11.3 versus 46.8 +/- 12.7; .05 < P < .1). In addition, the Ki-67-labeling index in endoscopically normal or slightly enlarged ampullary adenoma was significantly higher than that in markedly enlarged ampullary adenoma (51.8 +/- 11.4 versus 39.4 +/- 11.3; P < .05). Duodenal adenoma in FAP subjects was not found to have a higher proliferative activity or a smaller degree of apoptosis compared with those in non-FAP subjects. The smaller proliferative activity in larger ampullary adenoma may thus be related to the static nature of ampullary adenoma in FAP. 相似文献
55.
Y. Fujimura C. Nishishita J. Uchida M. Iida 《Journal of molecular medicine (Berlin, Germany)》1995,73(2):95-97
We describe a very rare case in which macroamylasemia was associated with ulcerative colitis of total colitis type. The patient's serum amylase isozyme pattern by electrophoresis showed a broad abnormal peak toward the side of the positive pole compared with regular salivary and pancreatic fractions. Sephadex G-200 column chromatography showed a sedimentation coefficient of 6.6 S. Amylase activity was bound to IgG. Double diffusion experiments demonstrated that amylase activity could be precipitated in gel by an antibody to the chain. Although inflammatory bowel disease is occasionally associated with hyperamylasemia due to pancreatitis, we emphasize that, when hyperamylasemia is recognized in patients with inflammatory bowel disease, macroamylasemia also should be considered.Abbreviations
MA
Macroamylasemia
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UC
Ulcerative colitis
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IBD
Inflammatory bowel disease 相似文献
56.
A cDNA library corresponding to mite protein was screened employing anti-Der f II antibody. Two possible clones were obtained, which contained plasmids, pFL1 and pFL11, respectively. Both plasmids had insertions of about 500 base pairs. The DNA sequences of the two insertions were determined, from which the amino acid sequences were deduced. The amino acid sequence of the purified native Der f II protein could be determined to 45 residues from the N-terminus. As a result of comparison, we concluded that the cDNAs prepared from live mite Dermatophagoides farinae corresponded to the mite allergen, Der f II. 相似文献
57.
58.
Hamasaki N Iida H Kinoshita S 《Rinsho byori. The Japanese journal of clinical pathology》2001,49(1):9-18
The quality of results obtained with molecular biology techniques depends on the control of preanalytical and analytical error associated with such techniques. Preanalytical error can be introduced during the isolation of DNA and RNA. The type of detergent used in cell lysis can affect the amplification of DNA by techniques such as the polymerase chain reaction(PCR). Ribonuclease(RNase) contamination is a serious problem in the isolation of undegraded RNA, and, thus, this enzyme should be inhibited. Anticoagulants used for blood collection can affect the quality of results with molecular biology techniques. The control of contamination from the working environment is essential to the minimization of preanalytical, analytical and postanalytical error. Molecular biology techniques for a wide range of clinical laboratory tests have been established in hospitals such as clinical laboratory tests for infections, molecular diagnoses of leukemia and aberrant genes in metabolism. 相似文献
59.
Summary The replication in RL-33 cells (rabbit lung cell line) of herpesvirus tamarinus isolated from cotton-topped marmosets(Saguinus oedipus) was investigated by electron microscopy. In the early stages of infection, ring-shaped and granular structures, and fibrillar materials were recognized in the nucleus. Immature particles were often found in such nuclei. The envelope of the virus was formed by budding through intracytoplasmic membranes, the inner nuclear membrane or the membrane of intracytoplasmic vacuoles. Virus particles which appeared to be budding through the plasma membrane were also observed. Aberrant viral forms were produced by independent budding of both the inner and outer nuclear membranes. The mature particles once enveloped acquired a second envelope by budding through intracytoplasmic double membranes or the outer nuclear membrane. Unusual virus-associated structures were observed in the cytoplasm and nucleus. Virus particles appeared to be released by the process of reverse phagocytosis.With 19 Figures 相似文献
60.
K Nagaki K Iida M Okubo S Inai 《International archives of allergy and applied immunology》1978,57(3):221-232
The reaction mechanisms of beta1H were studied. The generation of alternative pathway C3 and C5 convertases on the cell surface as well as in the fluid phase was inhibited by beta1H globulin. The cell preparation bearing the C3b site could bind beta1H with little effect on the C3b hemolytic activity. Bound beta1H was dissociated by the action of C3bINA and C3bINA-treated C3b bearing cell did not bind beta1H anymore. Cell-bound beta1H was also dissociated by the action of B (or Bb). From these and other results, the following conclusions were obtained. The C3b site-bearing cell could bind beta1H on the C3c region of C3b molecules facilitating the C3bINA action on C3b, and beta1H shared the same binding site with B (or Bb) inhibiting the generation of the alternative pathway convertases competitively. 相似文献