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1.
A. G. Carnon A. Ssemwogerere D. W. Lamont D. J. Hole E. A. Mallon W. D. George G. R. Gillis 《BMJ (Clinical research ed.)》1994,309(6961):1054-1057
OBJECTIVE--To investigate the relation between socioeconomic deprivation and pathological prognostic factors in women with breast cancer as a possible explanation for socioeconomic differences in survival. DESIGN--Retrospective analysis of data from cancer registry and from pathology and biochemistry records. SETTING--Catchment areas of two large teaching hospitals in Glasgow. SUBJECTS--1361 women aged under 75 who had breast cancer diagnosed between 1980 and 1987. MAIN OUTCOME MEASURES--Tumour size, axillary lymph node status, histological grade, and oestrogen receptor concentration in relation to deprivation category of area of residence. RESULTS--There was no significant relation between socioeconomic deprivation and four pathological prognostic factors: 93 (32%) women in the most affluent group presented with tumours less than 20 mm in size compared with 91 (31%) women in the most deprived group; 152 (48%) of the most affluent group presented with negative nodes compared with 129 (46%) of the most deprived group; 23 (22%) of the most affluent group presented with grade I tumours compared with 12 (17%) of the most deprived group; and 142 (51%) of the most affluent group had a low oestrogen receptor concentration at presentation compared with 148 (52%) of the most deprived group. None of these differences was statistically significant. CONCLUSIONS--Differences in survival from breast cancer by socioeconomic deprivation category could not be accounted for by differences in tumour stage or biology. Other possible explanations, such as differences in treatment or in host response, should be investigated. 相似文献
2.
IgE antibodies in the sera of subjects allergic to beta-lactam antibiotics detect a spectrum of specificities ranging from side-chain groups to an entire penicillin or cephalosporin molecule. In addition to such structural heterogeneity of allergenic determinants, IgE antibodies in the sera of different allergic subjects show heterogeneous recognition responses. Detailed immunochemical studies were carried out on the sera of penicillin-allergic subjects that showed selective and unexpected reactions with the frequently prescribed penicillin, amoxicillin. Antibodies from one subject reacted only with the amoxicilloyl determinant while IgE from another subject showed multiple reactivity with penicilloyl and penicillanyl determinants of different penicillins but not with the amoxicilloyl determinant. Quantitative hapten inhibition studies revealed that the combining sites of the former antibodies were complementary to amoxicillin in a form that permits binding to the hydroxyaminobenzyl side-chain and the thiazolidine ring carboxyl. These conditions are satisfied with the drug in the '-oyl' but not in the '-anyl' form which involves linkage through the 2-carboxyl of the thiazolidine ring. With the second serum, adsorption studies showed that the wide-ranging reactivity of IgE was due to a single population of antibodies that detected a common specificity on the different penicillins. Combining site studies revealed clear recognition of the benzyl portion of the side-chain of benzylpenicilloyl, benzylpenicillanyl, ampicilloyl, ampicillanyl and amoxicillanyl determinants when free antibody access to the side-chain was possible but little or no recognition of the ring hydroxyl of amoxicillin. Such uninhibited access may not occur, however, when amoxicillin is conjugated in the '-oyl' form since opening the beta-lactam ring allows increased flexibility and rotation of the molecule and the possibility of close association of the hydroxyaminobenzyl side-chain of amoxicillin with the linked peptide carrier. In such close steric association, H-bonding involving the ring hydroxyl and amino acids of the carrier may prevent antibody access to the side-chain region of the amoxicilloyl determinant. 相似文献
3.
Atrial natriuretic peptide in the heart and pancreas 总被引:1,自引:0,他引:1
We used antisera to pure atrial natriuretic peptide to localise this peptide by immunocytochemistry in rat and human tissue. We showed that both rat and human atrial cardiocytes gave a positive reaction while ventricular cardiocytes were consistently negative. Peripheral islet cells in rat but not in human pancreas also showed positive staining for ANP. We showed by double labelling techniques that the ANP was present in the glucagon containing cells. 相似文献
4.
Radioactivity eventually destined for the chromatophore membrane of Rhodopseudomonas sphaeroides was shown in pulse-chase studies to appear first in a distinct pigmented fraction. The material formed an upper pigmented band which sedimented more slowly than chromatophores when cell-free extracts were subjected directly to rate-zone sedimentation on sucrose density gradients. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicated that the purified fraction contained polypeptide bands of the same mobility as light-harvesting bacteriochlorophyll alpha and reaction center-associated protein components of chromatophores; these were superimposed upon cytoplasmic membrane polypeptides. The pulse-chase relation was confined mainly to the polypeptide components of these pigment-protein complexes. It is suggested that the isolated fraction may be derived from sites at which new membrane invagination is initiated. 相似文献
5.
Expression of the E2 open reading frame of papilloma viruses BPV1 and HPV6b in Escherichia coli 总被引:4,自引:0,他引:4
A new expression vector, pRA10, has been constructed for the expression of the open reading frames (ORF) of bovine (B) and human (H) papilloma viruses (PV). This vector is a derivative of pAJ pi and contains 15 restriction sites proximal to the lambda PL promoter, offering considerable versatility for insertion of different ORFs. This vector was used specifically to express the E2 ORF gene products from BPV1 and HPV6b at high level in Escherichia coli. The genuine nature of these proteins was demonstrated by restriction map analysis of expression vector plasmids to insure proper orientation, nucleotide sequence analysis to demonstrate in-frame insertion, E2 ORF protein production by expression-vector plasmids, and not by appropriate controls and, immunoprecipitation of E2 proteins by antibody specific for a common N-terminal sequence derived from the expression vector. 相似文献
6.
BS Sabna Thankappan Bency Mahendran Ramasamy Muthusamy Gayathri Femil selta Daniel Raja Angayarkanni Jayaraman 《Probiotics and antimicrobial proteins》2021,13(4):993-1004
Probiotics and Antimicrobial Proteins - Gamma-aminobutyric acid (GABA) is a principal inhibitory neurotransmitter in the central nervous system and is produced by irreversible decarboxylation of... 相似文献
7.
Katherine R. Bull Andrew J. Rimmer Owen M. Siggs Lisa A. Miosge Carla M. Roots Anselm Enders Edward M. Bertram Tanya L. Crockford Belinda Whittle Paul K. Potter Michelle M. Simon Ann-Marie Mallon Steve D. M. Brown Bruce Beutler Christopher C. Goodnow Gerton Lunter Richard J. Cornall 《PLoS genetics》2013,9(1)
Forward genetics screens with N-ethyl-N-nitrosourea (ENU) provide a powerful way to illuminate gene function and generate mouse models of human disease; however, the identification of causative mutations remains a limiting step. Current strategies depend on conventional mapping, so the propagation of affected mice requires non-lethal screens; accurate tracking of phenotypes through pedigrees is complex and uncertain; out-crossing can introduce unexpected modifiers; and Sanger sequencing of candidate genes is inefficient. Here we show how these problems can be efficiently overcome using whole-genome sequencing (WGS) to detect the ENU mutations and then identify regions that are identical by descent (IBD) in multiple affected mice. In this strategy, we use a modification of the Lander-Green algorithm to isolate causative recessive and dominant mutations, even at low coverage, on a pure strain background. Analysis of the IBD regions also allows us to calculate the ENU mutation rate (1.54 mutations per Mb) and to model future strategies for genetic screens in mice. The introduction of this approach will accelerate the discovery of causal variants, permit broader and more informative lethal screens to be used, reduce animal costs, and herald a new era for ENU mutagenesis. 相似文献
8.
F. Lordan S. Damm E. Kennedy C. Mallon R. J. Forster T. E. Keyes J. H. Rice 《Plasmonics (Norwell, Mass.)》2013,8(4):1567-1575
Studies comparing the effect of adding two different nanoparticle compositions on the plasmonic properties of Au nanovoid arrays were undertaken. Surface-enhanced resonance luminescence and surface-enhanced resonance Raman studies comparing dispersed Ag nanoparticles and Ag nanoparticle aggregates on gold nanovoid arrays were undertaken. These studies showed that using Ag nanoparticle aggregates increased both luminescence and Raman efficiency relative to when dispersed nanoparticles were used; in addition, these studies also showed that adding dispersed Ag nanoparticles supported a more reproducible enhancement in luminescence and Raman across the substrate compared to using Ag nanoparticle aggregates. Finite element analysis simulations indicated that surface plasmon polariton distribution in the sample was affected by the presence of the Ag nanoparticles on the Au nanovoid array. 相似文献
9.
Nigel R Franks Eamonn B Mallon Helen E Bray Mathew J Hamilton Thomas C Mischler 《Animal behaviour》2003,65(1):215-223
We tested the decision-making abilities of emigrating ant colonies. The colonies had to choose a new nest site when presented with two or more potential nest sites, each with different attributes or different combinations of attributes. For Leptothorax albipennis colonies in the laboratory, darkness of the nest cavity, internal height of the cavity and width of the entrance were all important attributes. The colonies ranked these attributes: darkness of the nest site was more important than internal cavity height, which in turn was more important than entrance width. These choices conform to the logic of transitivity. In addition, the colonies used a sophisticated decision-making strategy in which they took all alternatives and all attributes into consideration. Furthermore, the ants, in effect, weighed the different values of different attributes. They also chose the best nest when presented with only one excellent nest among four mediocre ones or one excellent nest in an array of one excellent, one good and one mediocre. Altogether, our results suggest that these ant colonies, in deciding upon a new home, used a weighted additive strategy, one of the most computationally expensive and thorough decision-making strategies. Copyright 2003 The Association for the Study of Animal Behaviour. Published by Elsevier Science Ltd. All rights reserved. 相似文献
10.