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121.
In Japan, histiocytic necrotizing lymphadenitis (Kikuchi’s disease) is a relatively common reactive lesion affecting lymph nodes, but the histogenesis and pathogenesis of the disease have not been clarified. Alpha-interferon has a role in the body’s defense against, viral infections. Using a polyclonal antibody to human alpha-interferon, we found numerous cells, mainly histiocytes, containing alpha-interferon in affected foci in the lymph nodes from 24 patients with Kikuchi’s disease. Tubuloreticular structures, thought by some authors to be associated with the production of interferon, were detected by electron microscopy in histiocytes, activated lymphocytes and vascular endothelial cells in the affected foci. These results suggested that the formation of tubuloreticular structures is a secondary phenomenon following stimulation by alpha-interferon. Further, the activity of 2′–5′ oligoadenylate synthetase, which is induced by alpha-interferon and enhanced during the early or active stage of viral infection, showed increased levels of activity in the active stage of Kikuchi’s disease and decreased to normal levels in the convalescent stage 2 weeks later. These results suggested the possibility of a viral etiology for Kikuchi’s disease.  相似文献   
122.
Summary We developed a high-titer polyclonal antiserum to a glycoprotein tumor-associated antigen (TAA) by immunization of a baboon with the purified glycoprotein antigen. The baboon serum was fractionated into IgG and IgM components by DEAE Affi-Gel blue chromatography. The ability of the baboon IgM anti-TAA antibody to effect tumor cell lysis in the presence of complement was tested using a chromium-release assay. The baboon antibody was able to lyse melanoma target cells (20.8%–71.4% cytolysis), breast carcinoma cells (36.5%–38.9% cytolysis), and a neuroblastoma cell line (35.5% cytolysis) in the presence of complement but did not effect significant lysis of autologous lymphoblastoid cell lines (4.9% cytolysis) or peripheral blood lymphocytes from healthy volunteers (12.6% cytolysis). Cytolysis of melanoma target cells was completely inhibited by preabsorption of the IgM anti-TAA antibody with UCLA-SO-M14 (M14) cells and partially inhibited by preabsorption with several other melanoma cell lines. There was no significant inhibition of tumor cell lysis after preabsorption of the antibody with lymphoblastoid cell lines. Complement-dependent lysis of M14 targets could be blocked by addition of the purified antigen to the antibody prior to incubation with the tumor cells. Our results suggest that the glycoprotein TAA resides on the tumor cell surface and that the baboon IgM anti-TAA antibody recognizes the antigen on the cell surface and is able to fix complement and effect the lysis of the tumor cells.  相似文献   
123.
Summary The EF5.44 locus is in close proximity to the chromosome 5 region to which the genetic defect responsible for familial adenomatous polyposis has been mapped. We have devised two oligonucleotides that promote the specific polymerase chain reaction (PCR) amplificiation of a 365-bp sequence in this region. Analysis by denaturing gradient gel electrophoresis of the resulting fragment has unravelled individual differences that could be identified as a single base pair change in aMnlI restriction site. This PCR assayable polymorphism increases the informativeness at this locus, and should be useful in the presymptomatic diagnosis of familial adenomatous polyposis.  相似文献   
124.
We propose a nomenclature for the genes encoding the chlorophylla/b-binding proteins of the light-harvesting complexes of photosystem I and II. The genes encoding LHC I and LHC II polypeptides are namedLhca1 throughLhca4 andLhcb1 throughLhcb6, respectively. The proposal follows the general format recommended by the Commision on Plant Gene Nomenclature. We also present a table for the conversion of old gene names to the new nomenclature.  相似文献   
125.
Libraries of cosmid and plasmid clones covering the entire region of mtDNA from the liverwortMarchantia polymorpha were constructed. These clones were used for the determination of the complete nucleotide sequence of the liverwort mtDNA totally 186,608 bp (GenBank no. M68929) and including genes for 3 species of ribosomal RNAs, 29 genes for 27 species of transfer RNAs, and 30 genes for functionally known proteins (16 ribosomal proteins, 3 subunits of cytochromec oxidase, apocytochromeb protein, 3 subunits of H+-ATPase, and 7 subunits of NADH ubiquinone oxidoreductase). The genome also contains 32 unidentified open reading frames. Thus the complete nucleotide sequences from both chloroplast and mitochondrial genomes have been determined in the same organism. Plasmid clones are available upon the request. Gene names are represented according to Lonsdale and Leaver (1988) with modifications recommended by Lonsdale (personal communication).  相似文献   
126.
We have examined the amplification unit at chromosome band 11q13 in 12 primary tumors and one cancer cell line (A431) with 15 DNA markers. The amplified region and size varied from one tumor to another; the smallest amplicon was estimated to be 700 kb long and the largest was 4.5 Mb long at maximum, on the basis of a physical map. Furthermore, the DNA amplified in tumors was not always continuous, because in three cases one locus within the amplicon was not amplified. The amplified region common to all 13 cancers consisted of 500 kb of DNA which incorporated eight defined loci (BCL-1, cCI11-524, cCI11-283, cCI11-234, HBI-1, cCI11-454, HSTF1, and INT2). As two of them, cCI11-524 and cCI11-454, were found to contain DNA sequences conserved in other species, one or both of these loci might encode the gene(s) that may be associated with progression of these tumors.  相似文献   
127.
Fifty-four clones containing human inserts were selected from a cosmid library constructed from a somatic cell hybrid containing chromosome 11p15.3-p15.5 as its only human complement. In 32 of these clones, 63 polymorphic systems were identified with a panel of restriction enzymes: 57 conventional RFLP systems and 6 highly polymorphic VNTR systems. Although we examined the cosmid with only seven enzymes, 18 clones (including 6 VNTRs) were polymorphic with three or more enzymes. The results suggested that DNA sequences on the peritelomeric region of chromosome 11p tend to be highly variable. Because these markers are highly informative, they will be excellent resources for investigations of hereditary diseases and tumor suppressor genes in this region of chromosome 11.  相似文献   
128.
We have constructed a long-range contig of cosmid and YAC clones around D10S102, a locus that is tightly linked to the gene responsible for multiple endocrine neoplasia type 2A (MEN2A). With D10S102 as a starting point, a 360-kb cosmid contig was constructed by bidirectional genomic walking, and at least six fragments from these cosmids showed high sequence homology to other species. Five YAC clones were also isolated at the D10S102 locus, and they formed a contig covering 950 kb of genomic DNA. Furthermore, we obtained six RFLP systems from the contig, which will serve as new resources for fine-scale genetic linkage mapping of the MEN2A locus.  相似文献   
129.
Isolation and mapping of 88 new RFLP markers on human chromosome 8.   总被引:1,自引:0,他引:1  
M Emi  E Takahashi  K Koyama  K Okui  M Oshimura  Y Nakamura 《Genomics》1992,13(4):1261-1266
To obtain new RFLP markers for construction of a high-resolution map of human chromosome 8, a cosmid library was constructed from a somatic hybrid cell that contained chromosome 8 as the only human component in mouse genomic background. Eighty-eight new RFLP markers were isolated and characterized, and 71 of them were sublocalized to chromosomal bands by fluorescent in situ hybridization (FISH). Of these, 36 were localized to the short arm, 34 to the long arm, and 1 to the centromeric region. Five markers defined VNTR loci. This work represents the first extensive isolation and physical mapping of RFLP markers on human chromosome 8. These new markers will serve as useful resources for linkage mapping of loci for inherited diseases and for efforts to identify a putative tumor suppressor gene(s) on chromosome 8.  相似文献   
130.
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