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61.
BACKGROUND: IL-15 is a T(H)1-related cytokine that is involved in the inflammatory response in various infectious and autoimmune diseases. IL-15 has recently been shown to be upregulated in T-cell-mediated inflammatory disorders. The observations suggest a potential role for this cytokine in a variety of pathologic conditions, including T(H)1-mediated and T(H)2-mediated inflammatory diseases. OBJECTIVE: In this study, we searched for single nucleotide polymorphisms in the whole IL-15 gene and investigated their association with inflammatory and/or atopic phenotypes. METHODS: The screening for single nucleotide polymorphisms was performed by single-strand conformation polymorphism analysis. Genotyping of the identified polymorphisms was performed by restriction fragment length polymorphism. Genotypic association analysis used the Armitage trend test. Haplotype frequency estimation and subsequent testing for differences between cases and controls were performed by using the programs FASTEHPLUS and FAMHAP. RESULTS: We identified 5 novel noncoding nucleotide sequence variants, all of which were typed in our asthmatic, our atopic, and our control population. According to the Armitage trend test, none of the 5 polymorphisms is associated with the phenotype bronchial asthma or atopy. However, multilocus haplotype analysis based on simulations to find out whether the haplotype frequencies differed between cases and controls by using the program FAMHAP yielded a P value of 6.1 x 10(-5) in the asthmatic versus the control population, which is highly significant. Furthermore, we obtained a nominally significant result of P=.0232 for the atopic versus the control population by using FAMHAP. CONCLUSION: These results strongly underscore previous findings that suggest a potential role of this cytokine in allergic diseases.  相似文献   
62.
Tetraarylsuccinonitriles 2a – e were synthesized via oxidative dimerization of diarylacetonitriles 1a – e in basic media. The thermal decomposition of 2 results in two identical cyanodiarylmethyl radicals 3 . Both 1H and 13C NMR analyses of 1a – e and 2a – e and ESR spectra of 3a – e are presented and discussed. The results of ESR measurements provide a plausible explanation for the different reactivity of cyanodiarylmethyl radicals 3a – e in free radical polymerization.  相似文献   
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64.
Theileria annulata macroschizonts were isolated from bovine lymphoblastoid cells grown in cell culture. To release the parasites, the cells were homogenized under hypotonic conditions. Intact host lymphocyte nuclei were lysed and the resulting chromatin precipitate was degraded by DNase. Host cell fragments were removed by ion-exchange chromatography. As revealed by electron microscopy, the preparations were free of intact host lymphocytes, lymphocyte nuclei and organelles. Antisera raised in rabbits against purified macroschizonts showed a specific reaction with the intracellular parasite in the indirect immunofluorescence test and in immuno-electron microscopy.  相似文献   
65.
As part of the Human Genome Project, the Washington University Genome Sequencing Center has commenced systematic sequencing of human chromsome 7. To organize and supply the effort, we have undertaken the construction of sequence-ready physical maps for defined chromosomal intervals. Map construction is a serial process composed of three main activities. First, candidate STS-positive large-insert PAC and BAC clones are identified. Next, these candidate clones are subjected to fingerprint analysis. Finally, the fingerprint data are used to assemble sequence-ready maps. The fingerprinting method we have devised is key to the success of the overall approach. We present here the details of the method and show that the fingerprints are of sufficient quality to permit the construction of megabase-size contigs in defined regions of the human genome. We anticipate that the high throughput and precision characteristic of our fingerprinting method will make it of general utility.  相似文献   
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We describe a patient initially diagnosed with a chronic myeloproliferative disorder in the accelerated phase. Cytogenetic analysis showed the presence of two independent clones. One clone contained a typical Philadelphia (Ph) chromosome due to t(9;22)(q34;q11), as the sole abnormality which was proven molecularly to result in the b2a2-BCR/ABL fusion. The other clone displayed a complex karyotype with several structural and numerical aberrations including trisomy 11 and 22 but lacking a t(9;22) or any other structural abnormalities involving chromosomes 9 and 22. Fluorescence in situ hybridization demonstrated that the t(9;22) was present only in cells with two copies of chromosomes 11 and 22. In contrast, cells with trisomies 11 and 22 lacked evidence for a BCR/ABL fusion. Based on the genetic findings, simultaneous chronic and acute myelocytic leukemias were diagnosed rather than a blastic phase of a chronic myelocytic leukemia.  相似文献   
68.
Extraskeletal myxoid chondrosarcoma is a rare malignant soft tissue tumour that can be difficult to diagnose correctly, especially preoperatively. We describe four cases of extraskeletal myxoid chondrosarcoma of the extremities diagnosed by a multimodal approach. The cytological examination of fine-needle aspirates showed small and round, mildly pleomorphic cells lying in sheets and cords, but also dispersed within a myxoid and metachromatic intercellular substance. Histological, electron microscopic and immunocytochemical examination also yielded findings compatible with the diagnosis of extraskeletal myxoid chondrosarcoma. Cytogenetic analysis demonstrated a t(9;22)(q22;q12) in two tumours and a t(9;17)(q22;q11) in the third and fourth. The translocation t(9;22)(q22;q12) has been described repeatedly in extraskeletal myxoid chondrosarcoma but never in other tumours; hence, the detection of this pathognomonic chromosome abnormality in short-term cultured cells from fine-needle aspirates verified the diagnosis in two of the cases. The t(9;17)(q22;q11) found in the last two cases probably represents a new cytogenetic subgroup of extraskeletal myxoid chondrosarcoma as it, too, is unknown in other contexts. The multimodal approach taken in these four cases enabled a definite diagnosis of a rare malignant tumour whose cytological and histological features alone are usually not sufficiently distinct to rule out other differential diagnostic possibilities. Received: 16 March 1999 / Accepted: 1 June 1999  相似文献   
69.
We present a novel large German kindred of fatal familial insomnia (FFI) consisting of three branches and comprising more than 800 individuals of 12 generations, the largest pedigree of any familial prion disease known today. There is a wide spectrum of clinical presentations leading to misdiagnoses of Olivo-Ponto-Cerebellar Atrophy (OPCA), Parkinson's or Alzheimer's disease in addition to Creutzfeldt-Jakob disease (CJD) and Gerstmann-Str?ussler-Scheinker (GSS) syndrome. Molecular genetic analysis of the prion protein gene (PRNP) confirmed the mutation D178N segregating with methionine at the polymorphic codon 129 of PRNP in all 7 patients examined. This polymorphism at codon 129 is supposed to discriminate between familial CJD (fCJD) and FFI; the 129M allele determines FFI and 129V fCJD. Furthermore, heterozygosity at this site appears to induce prolonged disease duration as compared to the homozygous condition. The variability of the clinical and pathological findings documented for our patients indicates the difficulty in establishing the diagnosis of FFI on clinical and on pathological grounds alone. In three cases (IX-97, XI-21, V-2) followed up by us prospectively insomnia was an early and severe symptom; however, in case notes analyzed retrospectively this symptom was frequently missed. In contrast to previous reports and in agreement with recent studies we cannot confirm a clear relationship between the status of the M/V polymorphism at codon 129 and the age-of-onset of this disease.  相似文献   
70.
Zusammenfassung Bei 47 Patienten mit akuter Leukämie wurden die Ergebnisse einer voneinander unabhängigen Klassifizierung aufgrund der panoptischen Färbung einerseits und dem Ausfall cytochemischer Reaktionen andererseits (Peroxydase, PAS-Reaktion, Naphthol-AS-Acetat-Esterase) sowie das Ansprechen auf eine adäquate Induktionstherapie in den cytologisch und cytochemisch definierten Gruppen miteinander verglichen. In 42 Fällen stimmte die cytologische und cytochemische Differenzierung miteinander überein. Hinsichtlich des Ansprechens auf Therapie ergeben sich keine signifikanten Unterschiede, gleichgültig, ob man die AL nach cytologischen oder cytochemischen Kriterien gruppiert. Eine Ausnahme bildet der bei undifferenzierten AL cytochemisch charakterisierbare PAS-Typ, bei dem ein besseres Ansprechen auf Therapie als bei den Fällen ohne diagnostisch verwendbare cytochemische Aktivität wie auch bei den granulocytär differenzierten AL gefunden wurde. Hinsichtlich des Ansprechens auf Therapie verhalten sich die Erwachsenen mit PAS-Typ ähnlich günstig wie die Kinder.Mit Unterstützung der Deutschen Forschungsgemeinschaft.  相似文献   
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