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91.
Immunogenicity in guinea pigs and tolerance in grass pollen-sensitive volunteers of enteric-coated grass pollen allergens 总被引:2,自引:0,他引:2
A W Wheeler D C Henderson L J Youlten I I Al-Janabi B E Hickman I H Taylor D M Moran 《International archives of allergy and applied immunology》1987,83(4):354-358
An acid-insoluble, methacrylic acid, methyl methacrylate copolymer (Eudragit L-100) was used to give an enteric coating to a grass pollen extract in order to protect it against gastric degradation. Substantial protection against the degradative effects of simulated gastric secretion was demonstrated using this preparation which was well tolerated by grass pollen-allergic volunteers. The enteric-coated allergen induced a greater secondary antibody response than did an aqueous presentation when administered orally to guinea pigs which had been primed previously by subcutaneous injection. This result indicates that an effective hyposensitisation regimen could consist of a short series of initial parenteral injections, followed by an oral course of the protected allergen. 相似文献
92.
Expression of blood group antigens in urinary tract tumours: prospective fluorescence study using cryostat sections of fresh frozen tissues. 下载免费PDF全文
Cryostat sections of fresh frozen tissues were used in a prospective study of blood group H and A antigen fluorescence in 73 transitional cell carcinomas of the bladder. The aim was to evaluate antigen expression without subjecting the tumour tissues to organic solvents that extract blood group active glycolipids. Deletion of the genetically predicted antigen was twice as common in tumours of pT1 or greater stage than those of pTa stage and also twice as common in poorly differentiated than in moderately well differentiated tumours. The considerable heterogeneity and overlap, however, in patterns of reactivity in tumours of various histopathological stages and grades and the effect of secretor status on antigenicity meant that there was no obvious antigenic feature that correlated precisely with invasive stage or differentiation grade. It remains to be determined whether the antigen positive and antigen negative tumours represent different disease entities with differing clinical courses. Our results indicate, however, that studies of the blood group antigens in urinary tract tumours are more likely to be of value in research into biochemical disorders in the neoplastic process than in routine clinical assessment as a guide to treatment. 相似文献
93.
The hypophysis of the brook trout is irrigated by blood vessels which originate from the internal carotid arteries. These are: (1) branches of the ventral hypothalamic arteries that give rise to an extensive capillary plexus in the neurohypophysis from which vessels extend into all regions of the adenohypophysis; (2) branches of the caudal hypothalamic artery that irrigate the saccus vasculosus and continue anteriorly to supply the ventral areas of the meta-adenohypophysis; (3) a caudal hypophyseal artery which vascularizes a portion of the meta-adenohypophysis however, this vessel is not always present; (4) a pair of small arteries which supply the peripheral regions of the gland directly from the carotids. Most of the neurosecretory fibers of the preoptic-hypophyseal tract terminate close to capillaries in the neurohypophysis. A few axons extend into meso-adenohypophyseal tissue. It is suggested that the secretory activities of the pro-, meso- and metaadenohypophyses are governed by hypothalamic factors that are chiefly transmitted to the gland cells via the vascular system (indirect control). However, the activity of the meso-adenohypophysis may also be regulated by factors which are transmitted directly to the cells from the endings of neurosecretory fibers which have traversed the neurohypophysis (direct control). The distribution and abundance of neurosecretion in the ventral hypophysis suggest the possibility of storage of hypothalamic products within this region. 相似文献
94.
Staphylococcus epidermidis has been reported to bind to a number of host cell extracellular matrix proteins, including fibronectin. Here we report the identification of a fibronectin-binding protein from S. epidermidis. A phage display library of S. epidermidis genomic DNA was constructed and panned against immobilized fibronectin. A number of phagemid clones containing overlapping inserts were identified, and one of these clones, pSE109FN, contained a 1.4-kb insert. Phage pSE109FN was found to bind to fibronectin but not to collagen, fibrinogen, laminin, or vitronectin. However, pSE109FN also bound to heparin, hyaluronate, and plasminogen, although to a lesser extent than it bound to fibronectin. Analysis of The Institute for Genomic Research S. epidermidis genome sequence database revealed a 1.85-kb region within a putative 30.5-kb open reading frame, to which the overlapping DNA inserts contained within the fibronectin-binding phagemids mapped. We have designated the gene encoding the fibronectin-binding domain embp. A recombinant protein, Embp32, which encompassed the fibronectin-binding domain of Embp, blocked the binding of S. epidermidis, but not the binding of Staphylococcus aureus, to fibronectin. In contrast, a recombinant protein, FnBPB[D1-D4], spanning the fibronectin-binding domain of the S. aureus fibronectin-binding protein FnBPB, blocked binding of S. aureus to fibronectin but had a negligible effect on the binding of S. epidermidis. 相似文献
95.
96.
The Competencies Conference: Future Directions in Education and Credentialing in Professional Psychology was held in Arizona in November 2002. One of the workshops, Individual and Cultural Differences (ICD), focused on racism, homophobia, and ageism. The consensus was that self-awareness and knowledge about the three "isms" are critical components in the education and training of psychologists. This article, authored by four of the workshop attendees, is a review of the current research and theoretical literature. Implications that address both content and context in graduate programs and training sites are presented. This is one of a series of articles published in this issue of the Journal of Clinical Psychology. Several other articles that resulted from the Competencies Conference will appear in Professional Psychology: Research and Practice and The Counseling Psychologist. 相似文献
97.
The pteridine neopterin is a marker of immunological activation and has been shown to be a useful marker of graft-versus-host disease (GVHD) in bone marrow transplant patients. High levels of both neopterin and interferon-gamma (IFN-gamma) were produced in vitro during mixed lymphocyte responses, which may be considered to be a model of the primary events leading to GVHD. Neopterin was shown to be produced by monocytes in response to stimulation with IFN-gamma, but not other cytokines. However, the interleukins IL-1 alpha, IL-1 beta, IL-2, and tumour necrosis factor (TNF) alpha and beta, but not IL-6, stimulated neopterin production by unfractionated peripheral blood mononuclear cells (PBMC), and culture supernatants from PBMC stimulated with IL-1 alpha, IL-1 beta, IL-2 and IL-6, but not TNF-alpha or TNF-beta induced neopterin production following transfer to fresh monocyte cultures. It therefore appears that cytokines may generate neopterin by induction of IFN-gamma, by synergy with low levels of induced IFN-gamma, or by non-IFN-gamma-dependent mechanisms. 相似文献
98.
Many children who suffered acute lead poisoning in Queensland eventually died with contracted kidneys. In most cases the kidneys were granular and showed microscopically fibrosis, hypertensive vascular changes and "alterative glomerulitis". Clinically in these patients, hypertension and chronic renal insufficiency had always preceded death which was usually due to uraemia. In a minority of cases the kidneys showed the changes of benign hypertension but were unusually small; fibrosis and "alterative glomerulitis" were not present. Clinically these patients had had hypertension but minimal renal insufficiency and death was usually due to cerebral haemorrhage. The evidence indicates that lead caused severe damage to the kidney at the time of the lead intoxication by some mechanism other than hypertension. The sequence of events postulated comprises severe renal damage with destruction of glomeruli during childhood lead poisoning, disappearance of the destroyed tissue during childhood and adolescence, onset of hypertension in adolescence or early adult life, gradual onset and progress of chronic uraemia during which fibrosis and granularity developed. In milder cases the sequence is not complete because renal function has remained adequate. 相似文献
99.
Vesicular uptake of eosinophil peroxidase by guinea pig basophils and by cloned mouse mast cells and granule-containing lymphoid cells. 总被引:5,自引:3,他引:5 下载免费PDF全文
A. M. Dvorak S. J. Klebanoff W. R. Henderson R. A. Monahan K. Pyne S. J. Galli 《The American journal of pathology》1985,118(3):425-438
Guinea pig basophils, cloned mouse mast cells, and cloned mouse granule-containing lymphoid cells were found to utilize a vesicular transport system to internalize eosinophil peroxidase (EPO) added in vitro. Kinetic analysis indicated that EPO internalization involved the binding of EPO to the plasma membrane, the formation of complex surface invaginations, and the movement of EPO-laden vesicles, tubules, and vacuoles toward the center of the cells. EPO became associated with multivesicular bodies in granule-containing lymphoid cells and mast cells, with immature granules in mast cells, and with mature granules in basophils. In other cells, the endogenous production of granule peroxidases (neutrophils and eosinophils) or the prior uptake of exogenous peroxidatic substances (some basophils) precluded cytochemical analysis of granules for EPO. Vesicular transport of EPO provides a possible explanation for the variable detection of peroxidase activity in mast cells or basophils. It also provides a mechanism for sequestration of this potentially toxic material or for its storage for possible future use. 相似文献
100.
The priority test request form: a method for improving communication between the physician and the Emergency Clinical Biochemistry Laboratory. 下载免费PDF全文
A R Henderson 《Journal of clinical pathology》1979,32(2):97-99
Two forms--a priority test request form and a telephone results form--provide improved communication between the physician and the emergency laboratory of the Clinical Biochemistry Department. The priority test request form contains a list of available tests and it allows the physician to tell the laboratory exactly when emergency test results are required. The telephone results form ensures that the physician will receive a report, by telephone, of a test result although it may not be an urgent test. This allows a greater control of work flow, both routine and emergency, through the laboratory. 相似文献