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Sen Pathak 《Cancer Genetics and Cytogenetics》1980,1(3):281-289
Cytogenetic analysis using C-, G-, and Ag-nucleolus organizer region (NOR) staining techniques, performed on established cell lines as well as directly processed breast tumor effusions, revealed that: 1) chromosome No. 1 is involved in translocation; 2) based on 1q translocation chromosome, breast tumors could be classified into two groups; and 3) double minutes and homogeneously staining regions may be present in breast tumor cells in vivo as well as in vitro, and that homogeneously staining regions may exhibit some heterogeneity in staining. 相似文献
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Successful treatment of chronic idiopathic urticaria and angioedema with cimetidine alone 总被引:1,自引:0,他引:1
Jafar Farnam M.D. J. Andrew Grant M.D. Brock G. Guernsey Pharm. D. Joseph L. Jorizzo M.D. Emil R. Petrusa Ph. D. 《The Journal of allergy and clinical immunology》1984,73(6):842-845
We have studied a 50-year-old white man with chronic urticaria and angioedema who has responded to treatment with cimetidine alone for over 2 yr. In a double-blind, placebo-controlled study, cimetidine alone was at least as effective as chlorpheniramine in relief of urticaria and angioedema. Additionally, cimetidine significantly inhibited (p less than 0.01) the wheal response to histamine when it was compared to placebo. The inhibition of wheal response to histamine by cimetidine was significantly higher (p less than 0.05) than chlorpheniramine. The presence of predominantly H2- rather than H1-histamine receptors in the cutaneous blood vessels may be responsible for the therapeutic effects of cimetidine in this patient. 相似文献
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Vincent M. Riccardi Helen M. Hittner Uta Francke Jorge J. Yunis David Ledbetter Wayne Borges 《Cancer Genetics and Cytogenetics》1980,2(2):131-137
The role of del (11)(p13) as a cause of aniridia, with and without Wilms tumor, is strengthened by demonstration of this chromosome aberration in 3 patients: monozygous twin girls, both of whom have aniridia and mental retardation and one of whom has a Wilms tumor; and an unrelated boy with aniridia and ambiguous genitalia. The break points defining the interstitial deletion for the twins are 11p13 and 11p15.1, while for the boy they are 11p1302 and 11p14.1. These patients and their karyotypes substantiate the critical importance of chromosome band 11p13 (or its hemizygous representation) in the development of aniridia and an associated Wilms tumor diathesis, as had been suggested previously (Riccardi VM, Sujansky E, Smith AC, Francke U, (1978): Pediatrics 61, 604-610). 相似文献
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The acute effects of the deposition of papain in the lungs of 4-month-old rabbits have been investigated with an amount not sufficient to cause emphysematous changes. During the first 2 days of in vivo deposition when hemorrhaging and inflammation occur, the total amounts of collagen and elastin in the lung, into which the papain had been instilled, did not change but the concentrations of collagen and elastin decreased 20 and 25% respectively. The rates of synthesis of collagen and other proteins doubled. By 4 weeks, collagen and elastin concentrations returned to, or were slightly above, control levels. The histological appearance and mean linear intercepts of lung sections and the compliance curves of excised lungs of the treated animals were similar to controls by 2 weeks after papain administration. The rabbit lung thus appears able to repair mild injury due to proteolytic enzymes. 相似文献
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Mumps virus strains differ in their ability to induce cell fusion following an infection: strains with activeneuraminidase (NANase) fail to cause cell fusion, while strains with less active NANases cause cell fusion. When chymotrypsin is added to infected cells, cell fusion is amplified in a concentration-dependent manner for all mumps virus strains. Virions produced in such infections do not express HN glycoprotein-associated activities. Chymotrypsin treatment of purified mumps virus in vitro results in sequential cleavage into two glycopolypeptides, HNc1 (32K) and HNc2′ (41K), with concomitant loss of hemagglutinating and NANase activities, and infectivity. Further incubation with chymotrypsin causes complete degradation of HNc1 and digestion of HNc2′ to HNc2 (13K–19K). Both HNc2′ and HNc2 contain the [3H]palmitic acid label found in the HN polypeptide, which suggests that these fragments are associated with the viral membrane. Analyses of infected cells and released virions indicate that chymotrypsin acts similarly on HN exposed at the cell surface. Exogenous NAnase does not abolish the protease-augmented cell fusion though it does reduce cell fusion of untreated fusing strain infections. These results confirm that mumps virus HN glycoprotein is critically linked to cell fusion cytopathology and show that cyrptic cell fusion activity in nonfusing strain infections can be unmasked by the proteolytic removal of the HN glycoprotein. 相似文献
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DRw6 has been difficult to define serologically. In the present experiments we have developed T cell lines in order to characterize the components of a DRw6 haplotype. This was accomplished by priming T cells with allogeneic mononuclear cells mismatched for DRw6, Dw6, and MT2. Subsequently, three sublines with distinct reactivity patterns were derived by limiting dilution. The specificities detected by these sublines included: (a) a specificity found on a subset of cells positive for DRw6 which was inhibited by monoclonal antibodies against DS(DC), the human homologue of the murine IA-encoded molecules, (b) another DRw6-associated specificity blocked by an MT2-like antibody, and (c) an MT2-like specificity blocked by monoclonal antibodies reactive with a different MT2-associated determinant. These results show that more than one IE-like, as well as the DS/DC (IA-like) molecules, carry distinctive antigenic epitopes that can be recognized by allogeneic T cells. Primed T cell lines may be useful for a better definition of certain haplotypes which are at present difficult to characterize with serological reagents alone. 相似文献