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91.
The human cytotoxic hybridoma antibody 4166 (IgMχ) was generated by fusing an in vitro EBV-transformed B-LCL from a multiparous woman with the mouse-human heteromyeloma fusion partner CB-F7. In microcytotoxicity and IIF tests with B-LCLs as target cells, the mAb 4166 was specific for DQ3 ( = DQ7 + 8 + 9). However, when used for DQ typing of class-II-positive PBMCs, 4166 could be rendered functionally specific for DQ7 + 8and did not react with DQ9+ PBMCs. Binding of mAb 4166 to DQ8-positive cells was efficiently blocked by several allotype-specific mAbs recognizing DQ8. Other HLA class-II-specific mAbs were unable to inhibit. With the use of mAb 4166, it is possible to discriminate DQ7 + 8 from DQ9 in serologic DQ typing. 相似文献
92.
Paul bandenbussche Maurizio Divizia Martine Verhaegeb-Lewalle Akira Fuse Tsuguo Kuwata Erik de Clerq Jean Content 《Virology》1981,111(1):11-22
IFr, a subline of transformed human fibroblast cells, which is sensitive to the antiviral but resistant to the anticellular activity of interferon, was found to be equally well inducible as its parental cell line RSa for the two major interferon-mediated double-stranded RNA-dependent enzymatic activities, 2–5A synthetase and 73K phosphoprotein kinase. The induction of 2-5A synthetase as a function of interferon dose, the specific activity of the 2-5A synthetase, the nature of the 2-5A oligonucleotide products, and the activity of the 2-5A-activated endonuclease were essentially the same for both cell lines. The 73K phosphoprotein kinase was induced at a similar rate of activity, whether detected in solution or after immobilization on poly(I)·poly(C)-Sepharose. Our observations thus suggest that the induction of these two enzymatic activities are not sufficient for the anticellular activity of interferon. 相似文献
93.
Gastrointestinal somatostatinomas are rare. Only 56 cases with duodenal origin have been reported in the literature. The long-term
course of an untreated tumor like this is unknown.
We report a case of a male patient who lived 30 yr with an untreated metastatic duodenal somatostatinoma. This case suggests
that a duodenal somatostatinoma may be of low malignant potential and that expectancy when treating this tumor might be indicated. 相似文献
94.
Norihiro Suzuki Jan Erik Hardebo Jan K hrstr m Christer Owman 《Neuroscience letters》1989,100(1-3):123-129
Galanin (GAL)-positive nerve fibers in rat cerebral vessels were demonstrated by immunohistochemistry, and their origin in the trigeminal ganglia and pathway in the nasociliary nerve to the vessels was shown by retrograde tracer technique and nerve transection. Some fibers in the vertebrobasilar system appear to originate in extracranial sources. With the antiserum used only few GAL fibers could be seen in the vessels, mostly in the vertebrobasilar system. In neonatally sympathectomized animals a rich network could be visualized in most pial arteries - still particularly in the vertebrobasilar system - probably as a result of a diminished competition for nerve growth factor. No vasomotor effect of GAL could be detected in isolated segments of pial arteries, neither in normal nor in sympathectomized animals, which rules out a direct postsynaptic effect on vascular tone. GAL did not display prejunctional modulatory action on the adrenergic nerves present in the vascular preparations. A sensory function of GAL is discussed. 相似文献
95.
Claes Lundsteen Beth Bjerregaard Erik Granum John Philip Kim Philip 《Clinical genetics》1980,17(3):183-190
96.
97.
Bo Aronsson Marta Granstrm Roland Mllby Carl Erik Nord 《Journal of immunological methods》1983,60(3):341-350
Enzyme-linked immunosorbent assay (ELISA) was established with purified toxins from Clostridium difficile as antigene to measure antibody response in patiensts with pseudomembranous colitis (PMC) and prolonged antibiotic-associated diarrhoea (AAD). Positive ELISA titres were defined in a control population. Antibodies of IgG class against toxin B were demonstrated in 6/88 (7%) control sera and in 31/61 (51%) sera from 11/19 (58%) patients. Antibodies of IgA class were found in one patient while antibodies of IgM class were not demonstrated. ELISA antibodies against toxin A were not demonstrated. For comparison a neutralization test was performed and neutralizing antibodies to toxin B but not to toxin A were demonstrated in 10/61 (16%) sera from 4/19 (21%) patients and in none of the controls. ELISA was found to be a more sensitive assay than neutralization. ELISA antibodies were detected from the third week of the disease while neutralizing antibodies appeared after 5 weeks. Lack of an antibody response in ELISA seemed to correlate to a more severe colitis. 相似文献
98.
Epidemiological evidence suggests an inverse relationship between prostate cancer and serum vitamin D levels. We examined
the ability of cholecalciferol (vitamin D3), a calcitriol precursor, to inhibit or reverse cellular changes associated with malignant transformation and invasion and
explored its mechanisms of action. The RWPE2-W99 human prostate epithelial cell line, which forms slow-growing tumors in nude
mice, was used because it mimics the behavior of the majority of primary human prostate cancers. Cholecalciferol, at physiological
levels: (i) inhibited anchorage-dependent and -independent growth; (ii) induced differentiation by decreasing vimentin expression
with a concomitant decrease in motility/chemotaxis; (iii) decreased MMP-9 and MMP-2 activity with concomitant decrease in
invasion; and (iv) exerted its effects by up-regulating vitamin D receptor (VDR), retinoid-X receptor-α (RXR-α), and androgen
receptor (AR) in a dose-dependent manner. Furthermore, we found that RWPE2-W99 prostate cancer cells, similar to RWPE-1 cells
(Tokar and Webber. Clin Exp Metast 2005; 22: 265–73), constitutively express the enzyme 25-hydroxylase CYP27A1 which is markedly
up-regulated by cholecalciferol. Cholecalciferol has effects similar to those of calcitriol on growth, MMP activity, and VDR.
The ability of CYP27A1 to catalyze the conversion of cholecalciferol to 25(OH)D3 and of 25(OH)D3 to calcitriol has been reported. RWPE2-W99 cells, similar to RWPE-1 cells, appear to have the rare ability to locally convert
cholecalciferol to the active hormone calcitriol. Because it can inhibit cellular changes associated with malignant transformation
and invasion, we propose that cholecalciferol may be an effective agent for the treatment of prostate cancer. 相似文献
99.
100.
Puri Beena Nelson William Porter Kevin R. Henchal Erik A. Hayes Curtis G. 《Virus genes》1998,17(1):85-88
We have determined the complete nucleotide sequence and the deduced amino acid polypeptide sequence of the genome of a dengue-1
(DEN-1) virus strain isolated from a patient on Nauru in the Western Pacific in 1974 (West Pac 74). The complete genome is
10,735 nucleotides in length and contains a single long open reading frame of 10,176 nucleotides encoding a polyprotein of
3392 amino acids. When compared to DEN-1 Singapore S275/90, the nucleotide and amino acid sequence homology are 94% and 97.8%,
respectively.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献