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41.
C. Wood B. Sina C. G. Webster D. Kurgansky C. B. Drachenberg E. A. Reedy 《Journal of cutaneous pathology》1992,19(2):128-133
A 57-year-old woman with cutaneous mastocytosis of 23 years duration developed a hyperpigmented abdominal plaque composed of confluent indurated papules that enlarged for a period of 1 year to 12 x 8 cm. Biopsy showed dermal infiltration by closely packed spindle-shaped mast cells, fibroblasts, collagen, and scattered lymphocytes, predominantly T-suppressor cells. Electron microscopy showed close contact between mast cells, fibroblasts, and lymphocytes. Piecemeal mast cell degranulation and extrusion of mast cell granules was seen, with rare mast cell granules in fibroblasts, and collagen fibers in peripheral and perinuclear endoplasmic reticulum of mast cells. the term Fibrous mastocytoma is suggested for this tumor-like dermal fibrosis, possibly induced by lymphokines. 相似文献
42.
43.
J C Pinilla B Webster M Baetz B Reeder S Hattori L Liu 《JPEN. Journal of parenteral and enteral nutrition》1992,16(5):408-412
The objective of this study was to evaluate body composition as measured by bioelectric impedance analysis using splints and body positions differing from the standard supine position. Forty-three patients, randomized into two groups of different body positions, and 101 healthy volunteers were prospectively studied. Resistance and reactance of body tissues were measured by bioelectric impedance analysis. Body composition is described by a three-compartment model composed of body fat, body cell mass, and extra cellular mass. The patients were measured in the standard supine position and then randomized into two groups. They were then remeasured with the appropriate splinting device or position change. Volunteers were measured in the standard supine position and all four alternative positions. There was a statistically significant difference demonstrated in whole body resistance, whole body reactance, body cell mass, and the ratio of extracellular mass to body cell mass in some body positions. The percentage of change with different body positions and splints, when compared with the standard supine position, was generally below 2%, a clinically insignificant difference. We conclude that the reliability of resistance and reactance as measured by bioelectric impedance analysis is clinically valid using any of the tested body positions and/or splints. The three-compartment model may be a useful concept to measure body composition changes in both healthy and sick persons. 相似文献
44.
H B Muss J A Blessing P Hanjani J H Malfetano G M Kemp K Webster 《American journal of clinical oncology》1992,15(4):363-364
Eighteen evaluable patients with recurrent or metastatic nonsquamous carcinoma of the uterine cervix were treated with 1,500 micrograms/m2 of echinomycin every 4 weeks. Seven patients had received prior chemotherapy. There was one complete response (5.6%), 95% confidence interval for response of 0-27%. The major toxicity was nausea and vomiting, which was moderate to severe in eight patients. Myelosuppression was minimal. Echinomycin in this dose and schedule displays minimal activity in patients with advanced nonsquamous carcinoma of the cervix. 相似文献
45.
46.
M D Brewer M N Burgess R J Dorgan R L Elliott P Mamalis B R Manger R A Webster 《Journal of medicinal chemistry》1989,32(9):2058-2062
A series of 1,2,3,4,6,7,8,12b-octahydropyrazino[2,1-alpha][2] benzazepine derivatives was prepared and the cestocidal activity of the compounds evaluated in an in vitro Taenia crassiceps screen. Many of these derivatives proved to be highly active, and 2-(cyclohexylcarbonyl)-4-oxo-1,2,3,4,6,7,8,12b- octahydropyrazino[2,1-alpha][2]benzazepine, epsiprantel (BAN) (22), was selected for further development. The structure-activity relationships are discussed. 相似文献
47.
EDE for exposure with protective aprons 总被引:4,自引:0,他引:4
E W Webster 《Health physics》1989,56(4):568-569
48.
Antigenic and biological characterization of influenza virus neuraminidase (N2) with monoclonal antibodies 总被引:5,自引:0,他引:5
Competitive radioimmunoassays using monoclonal antibodies established that the neuraminidase of A/RI/5+/57 (H2N2) influenza can be divided into four overlapping antigenic regions. Antigenic regions 1 and 4 are sufficiently far apart so that there was no competition between antibodies for these sites. Region 1 is conserved in neuraminidases from N2 viruses over a 10-year period, while the other regions changed antigenically during this time. The antibodies belonging to groups 2 and 3 completely inhibited catalytic activity on fetuin substrate, whereas antibodies in groups 1 and 4 inhibited weakly or not at all. Antigenic region 2 can be further divided into four overlapping areas (2a, 2b, 2c, and 2d) based on the reactivity patterns of monoclonal antibodies with antigenic variants, chemically modified neuraminidase, and the ability of the antibodies to inhibit enzyme activity of different molecular weight substrates. Previous studies [R. G. Webster, V. S. Hinshaw , and W. G. Laver (1982) Virology 117, 93-104; D. C. Jackson and R. G. Webster (1982) Virology 123, 69-77] characterized only region 2 of the neuraminidase molecule. Each of the monoclonal antibodies inhibited virus release from MDCK cells when incorporated in an agar overlay, and some antibodies in each group inhibited hemagglutination by intact virus, but only antibodies in group 2 neutralized virus in embryonated eggs and permitted selection of antigenic variants. The results indicate that antibodies to some antigenic sites on the neuraminidase may inhibit virus release more efficiently than others, depending on their relation to the enzyme active center. None of the monoclonal antibodies inhibited the hemolytic activity of viruses possessing N2. Based on antigenic mapping and biological properties of the monoclonal antibodies, a topographical map of the neuraminidase can be constructed. It is proposed that antigenic regions 1 and 4 are spacially separated and, based on their failure to inhibit biological activity, may be located on the bottom surface of the molecule; region 3 may be on the top surface of the molecule but at some distance from the catalytic center. Antigenic region 2 probably encompasses most of the top surface of the molecule; region 2d being closest to the enzyme center, with subregions 2a and 2b adjacent to it on the top surface. Chemical treatment of the neuraminidase with trinitrobenzenesulfonic acid (TNBS) causes modification of the 2b region, confirming the antigenic mapping results. 相似文献
49.
Hamvas RM Johnson M Vlieger AM Ling C Sherriff A Wade A Klein NJ Turner MW Webster AD 《Infection and immunity》2005,73(8):5238-5240
Polymorphisms in exon 1 of the MBL-2 gene, resulting in reduced plasma levels of mannose binding lectin, were significantly overrepresented in 23 patients with primary antibody deficiency and culture-proven mycoplasma infections (P = 0.0038). This association persisted with the inclusion of a further nine suspected (doxycycline-responsive) cases (P = 0.0087). The lectin was shown to bind to three strains of mycoplasma. 相似文献
50.
Increased gamma delta T cells in acute Plasmodium falciparum malaria 总被引:13,自引:0,他引:13
The T cell receptor of gamma delta is normally expressed on a small percentage of peripheral lymphocytes. Although the role of gamma delta T cells in the physiologic immune response is still unknown, there is accumulating evidence that gamma delta T cells may participate in the immune response to mycobacterial and other infectious organisms. In this study, we have quantitated the number of circulating gamma delta T cells during acute Plasmodium falciparum malaria. The results indicate that gamma delta T cells are elevated during the acute infection and remain elevated for at least 4 weeks during convalescence. T cells may participate in the immune response against P. falciparum by functioning as non-MHC restricted cytotoxic cells against intraerythrocytic parasites. Alternatively, lymphokines may be produced on antigen stimulation which may have antiparasitic activity. 相似文献