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Berry MJ, Wattam TA, Willets J, Lindner N, de Graaf T, Hunt T, Gani M, Davis PJ, Porter P. Assay and purification of Fv fragments in fermenter cultures: design and evaluation of generic binding reagents. J Immunol Methods 1994; 167:173-82. [PMID: 7508476 DOI: 10.1016/0022-1759(94)90086-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Fv fragments whose genes have been cloned using common PCR primers carry identical peptide motifs at their termini. We have raised antibodies against the C-terminal motif of the VH chain GQGTTVTVSS and evaluated their utility as reagents for the assay and purification of Fvs in the fermenter culture. Three different Fvs were included in the investigation. We found that the motif was exposed and available for capture when Fv fragments were blotted onto nitrocellulose paper or adsorbed directly onto microtiter plates. In contrast, the motif was either partially or totally obscured when the Fv was complexed with immobilised antigen or when free in solution. This reactivity profile enabled us to develop a general-purpose assay for Fv protein, but not a general-purpose assay for monitoring active Fv. The apparent inaccessibility of the C-terminus of VH conflicts with currently held views on the three-dimensional structure of these molecules.
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Guha S, Kang K, Porter P, Roach JF, Remy DE, Aranda FJ, Rao DV. Third-order optical nonlinearities of metallotetrabenzoporphyrins and a platinum poly-yne. OPTICS LETTERS 1992; 17:264-266. [PMID: 19784296 DOI: 10.1364/ol.17.000264] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The third-order optical nonlinearities of two metallotetrabenzoporphyrins and a platinum poly-yne dissolved in tetrahydrofuran were measured by using picosecond and nanosecond laser pulses. The pulse-width-dependent measurements indicated that excited-state absorption was present in both classes of material along with non-resonant two-photon absorption.
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53
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Moe RE, Moe KS, Porter P, Gown AM, Ellis G, Tapper D. Expression of Her-2/neu oncogene protein product and epidermal growth factor receptors in surgical specimens of human breast cancers. Am J Surg 1991; 161:580-3. [PMID: 1674411 DOI: 10.1016/0002-9610(91)90904-r] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Her-2/neu protein product was immunocytochemically analyzed in 139 breast cancers. Epidermal growth factor receptors were similarly analyzed in 74 breast cancers from the same patient pool. These results were also separated on the basis of estrogen receptor proteins and of combined aneuploidy with elevated S-phase from flow cytometry. Invasive breast cancer yielded a positive label for Her-2/neu protein (26%) and for epidermal growth factor receptor (25%), with no significant difference. Correlations with estrogen receptor labeling yielded differences significant inversely for both Her-2/neu protein (p less than 0.02) and epidermal growth factor receptor (p less than 0.01). Positive Her-2/neu protein labels correlated with a positive combination of aneuploidy and elevated S-phase (37%) and a negative combination of aneuploidy and elevated S-phase (21%), with a statistically nonsignificant difference. Positive epidermal growth factor receptor cases with aneuploidy and an elevated S-phase (75%) and without aneuploidy and elevated S-phase (42%) did differ with significance at p less than 0.05. There were eight cases positive for both Her-2/neu protein and epidermal growth factor receptor, four of six cases with negative estrogen receptor, four of six cases with negative estrogen receptor, six of six cases aneuploid, and five of six cases with an elevated S-phase. All eight cases had threatening disease--either stage III or stage IV, with one case of extensive ductal carcinoma in situ (comedo). Correlation of negative Her-2/neu protein with negative epidermal growth factor receptor was significant (p less than 0.05) in 74 cases. However, positive Her-2/neu protein did not correlate with positive epidermal growth factor receptor; there was a trend toward inverse correlation. We conclude that epidermal growth factor receptor labeling results show similarities to Her-2/neu protein results, but epidermal growth factor receptor tended to correlate with unfavorable ploidy and S-phase. Epidermal growth factor receptor labeling might be useful in breast cancers with macrocysts reported to show high epidermal growth factor activity.
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Porter P. Medicare Catastrophic Act repealed. J Am Vet Med Assoc 1990; 196:688-9. [PMID: 2407702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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55
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Henderson GI, Baskin GS, Horbach J, Porter P, Schenker S. Arrest of epidermal growth factor-dependent growth in fetal hepatocytes after ethanol exposure. J Clin Invest 1989; 84:1287-94. [PMID: 2677050 PMCID: PMC329789 DOI: 10.1172/jci114296] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Exposure of the fetal rat hepatocyte to ethanol in vitro blocks epidermal growth factor (EGF)-dependent cell replication. To define possible mechanisms for this growth arrest, we determined the effects of ethanol on EGF binding and EGF receptor (EGF-R) levels. During a 24-h exposure to ethanol (1.7 mg/ml, 31 mM), cell replication was completely blocked while EGF binding per cell doubled. This effect was no specific for EGF, with variable degrees of increased binding noted for insulin, transferrin, and glucagon. Significantly increased EGF binding was seen after 6 h of ethanol exposure, and both growth arrest and enhanced EGF binding were reversed within 12 h of ethanol withdrawal. Increases in both "high" and "low" affinity sites were seen, with no changes in the apparent Kd's. Total RNA, beta-actin mRNA, and EGF-R mRNA were increased 50-70% in ethanol exposed cells. However, direct measurements of EGF-R synthesis rates by [35S]methionine incorporation revealed no differences between control and ethanol exposed cells. Internalization of EGF-R was significantly altered by ethanol exposure. A 2-h incubation resulted in the internalization of 57% of the ligand in control cells, while only 31% of bound EGF was internalized in the ethanol exposed cells. Thus, the enhanced EGF binding may be due to decreased efficiency of internalization.
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Titus S, Porter P. Orem's theory applied to pediatric residential treatment. PEDIATRIC NURSING 1989; 15:465-8, 556. [PMID: 2587104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Nurses working in multidisciplinary pediatric residential treatment facilities must maintain a clarity of domain. The Orem Self-Care Model is evaluated for the use in settings of this kind and shown to be both appropriate and adaptable.
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Cargill R, Engle K, Gardner CR, Porter P, Sparer RV, Fix JA. Controlled gastric emptying. II. In vitro erosion and gastric residence times of an erodible device in beagle dogs. Pharm Res 1989; 6:506-9. [PMID: 2762227 DOI: 10.1023/a:1015976709043] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
An erodible gastric retention device fabricated from various polymeric blends was examined in vitro for its dissolution properties and in vivo in fasting dogs for assessment of its gastric retention potential. Dissolution studies were conducted with extruded rods of polymer blends to assess their potential as candidates for the erodible component of a gastrically retained device. Based on results from dissolution studies, rods of poly(ortho ester)/polyethylene blends (POE/PE) (45% erosion at pH 1.5 and 24 hr) were used to fabricate arms for tetrahedron-shaped devices. Corners for the tetrahedral device were fabricated from Silastic 382 loaded with 15% barium sulfate for X-ray visualization. Beagle dogs were dosed with tetrahedron-shaped test devices administered in gelatin capsules and gastric retention monitored by X ray over a 24-hr period. A comparison of in vitro erosion rates and in vivo performance of various polymer blends indicated a definite trend for increased gastric retention of devices made from the more slowly eroding blends. The results indicate that the blending of erodible and nonerodible polymers is a valid approach for obtaining materials that will provide the necessary structural properties to achieve gastric retention yet lose integrity within a desired time.
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Porter P. AVMA life insurance policies. J Am Vet Med Assoc 1988; 193:43-4. [PMID: 3417524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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59
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Porter P. Medical care costs forcing rate increases. J Am Vet Med Assoc 1988; 192:626-7. [PMID: 3372312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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60
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Gani M, Coley J, Porter P. Epitope masking and immunodominance--complications in the selection of monoclonal antibodies against HCG. Hybridoma (Larchmt) 1987; 6:637-43. [PMID: 2449390 DOI: 10.1089/hyb.1987.6.637] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Spleen cells from Balb/c mice immunized with HCG were subjected to the normal hybridoma procedures. The resulting MCA's (from 78 clones) were evaluated in radioimmunoassay, haemagglutination and enzyme immunoassay with whole HCG. The RIA analysis was extended to include HCG subunits and intact LH. The alpha-chain of HCG was found to be strongly immunodominant, as shown by the very high frequency (46 of 78) of MCA's directed at the alpha-chain epitopes. These antibodies would bind luteinizing hormone as well as HCG. Only 1 of the 78 clones was specific for the B subunit of HCG, in RIA. This clone was later found to be positive for LH in EIA, thus making the derivation of antibodies specific for this B-epitope extremely difficult. Most MCA's were found to be applicable in the three types of assay systems (48 of 78), but some were compatible in just one or two of the systems. These differences are believed to be due to epitope masking resulting from the way in which the antigen was handled and presented in the different systems.
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Anderson DV, Tucker EM, Powell JR, Porter P. Bovine monoclonal antibodies to the F5 (K99) pilus antigen of E. coli, produced by murine/bovine hybridomas. Vet Immunol Immunopathol 1987; 15:223-37. [PMID: 2888227 PMCID: PMC7133685 DOI: 10.1016/0165-2427(87)90085-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/02/1987] [Indexed: 01/03/2023]
Abstract
Lymph node cells from calves immunized with purified pilus antigen of K99+ enterotoxigenic E. coli (ETEC) were fused with mouse myeloma (NSO) cells, and with non-Ig producing mouse/calf hybridomas or with a bovine Ig-producing mouse/calf/calf secondary hybridoma. Lines secreting bovine monoclonal IgG1 specific for K99 pilus antigen in an ELISA were obtained in each case. The two lines derived from xenohybridoma fusion partners have been secreting anti-K99 bovine monoclonal antibody for over one year in continual passage. None of the antibodies cross-reacted with other pilus types including K88, CFAI, CFAII, 987P or CP; they all inhibited agglutination of horse RBC (which have a K99 receptor) in the presence of K99 antigen; they showed positive fluorescence in an indirect binding assay on K99+ ETEC and inhibited K99+ ETEC adhesion to piglet enterocytes. These antibodies have potential prophylactic and therapeutic use in control and treatment of diarrhoea.
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Barratt M, Twohig B, Hall H, Porter P. Hypersensitivity to dietary components in young farm animals: immunisation of calves for IgE antibody responses. Res Vet Sci 1985. [DOI: 10.1016/s0034-5288(18)31772-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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63
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Barratt ME, Twohig BM, Hall H, Porter P. Hypersensitivity to dietary components in young farm animals: immunisation of calves for IgE antibody responses. Res Vet Sci 1985; 39:62-5. [PMID: 4035093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
An immunisation schedule is described that reproducibly induces long latent period skin sensitising antibody (immunoglobulin) in calves by a combined oral/parenteral route. This response is only directed towards the protein component of the antigen and is boosted upon challenge injection.
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Barratit M, Senior S, May K, Hall H, Porter P. Hypersensitivity to dietary components in young farm animals: isolation and partial purification of bovine immunoglobulin E. Res Vet Sci 1984. [DOI: 10.1016/s0034-5288(18)31934-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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65
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Barratt ME, Senior SJ, May K, Hall H, Porter P. Hypersensitivity to dietary components in young farm animals: isolation and partial purification of bovine immunoglobulin E. Res Vet Sci 1984; 37:93-6. [PMID: 6433413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
An antibody of known specificity and active in long (72 hours) latent period passive cutaneous anaphylactic reactions, was isolated and partially purified from bovine serum. This antibody was not associated with immunoglobulins IgG, IgM or IgA. A rabbit antiserum raised against this antibody and used as an immunoabsorbent, successfully recovered skin sensitising antibody from bovine reaginic serum.
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Porter P, Linggood MA. Novel mucosal anti-microbial functions interfering with the plasmid-mediated virulence determinants of adherence and drug resistance. Ann N Y Acad Sci 1983; 409:564-79. [PMID: 6191616 DOI: 10.1111/j.1749-6632.1983.tb26899.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Mucosal antibodies in vivo and in vitro interfere with the stability of plasmids coding for important virulence determinants in porcine enteropathogenic E. coli (EEC), such as the adhesion determinants K88ab and K88ac. The effector antibody is not directed against K88 antigens and is not serotype specific, but an antigen common to K88+ strains is implicated. Further lack of pathogen specificity is exemplified by antibody elimination of the more recently discovered K88ad plasmid. Antibodies that interfere with K88 plasmids do not affect K99, which now appears as an alternative adhesion factor in porcine enteropathogenic E. coli. This plasmid can be eliminated, however, by antibodies having K99 specificity. In extending the studies to drug-resistance plasmids, further evidence has emerged that mucosal antibodies may assist in host control of the reservoir of R factors in the intestinal microflora. A major effector mechanism is that secretory IgA and IgM antibodies from orally immunized pigs can block the transfer of R factors between donor and recipient strains of E. coli.
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Barratt MEJ, Allen WD, Porter P. IMMUNOLOGY OF THE MUCOSAL RESPONSE TO ANTIGENS OF DIETARY AND MICROBIAL ORIGIN AFFECTING INTESTINAL FUNCTION AND NUTRITIONAL PERFORMANCE. Ann N Y Acad Sci 1983. [DOI: 10.1111/j.1749-6632.1983.tb26919.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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68
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Davis PJ, Porter P. EIMERIA TENELLA: CONTROL OF PARASITIC BEHAVIOR THROUGH MUCOSAL IMMUNITY AND IN-FEED IMMUNIZATION. Ann N Y Acad Sci 1983. [DOI: 10.1111/j.1749-6632.1983.tb26931.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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69
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Porter P, Linggood MA. Development of oral vaccines for preventing diarrhoea caused by enteropathogenic Escherichia coli. J Infect 1983; 6:111-21. [PMID: 6348176 DOI: 10.1016/s0163-4453(83)92632-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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70
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Abstract
School problems are common in children with neuromuscular disease irrespective of their degree of handicap. They are related to difficulties in transportation and access, difficulties with adaptation of school tasks to the motorically handicapped, and difficulties that arise because of misunderstanding of the disease processes by teachers and parents. Most of these can be easily rectified by efforts by the clinic staff to educate school personnel and to enlist them as members of the treatment team. In view of the importance of the school experience to this group of patients, it is urged that these problems be identified and aggressively managed by those involved in the care of neuromuscularly handicapped children.
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Porter P. Marking of breast tissue by needle localization under mammographic control. Radiography (Lond) 1982; 48:153-6. [PMID: 7134396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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72
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Porter P. Setting up a counselling service in the workplace. OCCUPATIONAL HEALTH; A JOURNAL FOR OCCUPATIONAL HEALTH NURSES 1982; 34:332-7. [PMID: 6921598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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73
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Keren DF, Kern SE, Bauer DH, Scott PJ, Porter P. Direct demonstration in intestinal secretions of an IgA memory response to orally administered Shigella flexneri antigens. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1982; 128:475-9. [PMID: 7033378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Jefferis R, Lowe J, Ling NR, Porter P, Senior S. Immunogenic and antigenic epitopes of immunoglobulins I. Cross-reactivity of murine monoclonal antibodies to human IgG with the immunoglobulins of certain animal species. Immunology 1982; 45:71-7. [PMID: 6173313 PMCID: PMC1555158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Antibody-producing hybridoma clones have been isolated following immunization of mice with human IgG. Twenty-five monoclonal antibodies (nine anti-C gamma 3, fourteen anti-C gamma 2, one anit-kappa and one anti-lambda) were selected for study of their cross-reactivity with the IgG of fifteen mammalian species and chicken immunoglobulin. Each antibody exhibited a unique reaction profile suggesting that human IgG expresses a very large repertoire of immunogenic epitopes. Whilst some antibodies showed a very restricted cross-reactivity profile for others a very wide reactivity profile was observed-including two clones producing autoantibodies. Antibodies demonstrating cross-reactivity between human Fc gamma and 7S chicken immunoglobulin allow its definitive assignment as a homologue of human IgG. Four clones demonstrated specificity for bovine IgG subclass gamma 1 and gamma 2 and the degree of reactivity allows their application to qualitative and quantitative assay systems. These studies suggest new perspectives for the characterization of immunoglobulins and the standardization of anti-immunoglobulin reagents.
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Keren DF, Kern SE, Bauer DH, Scott PJ, Porter P. Direct demonstration in intestinal secretions of an IgA memory response to orally administered Shigella flexneri antigens. THE JOURNAL OF IMMUNOLOGY 1982. [DOI: 10.4049/jimmunol.128.1.475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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