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71.
Postdural puncture cerebral spinal fluid (CSF) leak most often manifests as a postdural puncture headache (PDPH). The reported frequency in young children varies (1-4). Persistent CSF leak may also be present without PDPH. We present a case of postoperative nausea and vomiting resulting from a presumed lumbar CSF leak in a nonverbal child after surgical placement of a permanent intrathecal catheter. Treatment with an epidural blood patch (EBP) via the caudal approach resulted in complete relief of symptoms. 相似文献
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Jill L. Bashford R. Adrian Robins Michael R. Price 《International journal of cancer. Journal international du cancer》1993,54(5):778-783
C595 is a murine lgG3 monoclonal antibody (MAb) raised against human urinary mucin. C595 antibody binds to the protein core of the MUC-1 mucin (the polymorphic epithelial mucin, PEM) which is elevated in tissue and secretions from human breast carcinomas. The antibody defines the tetrameric epitope, R P A P. In the present study, a syngeneic antiidiotypic MAb, 911, was raised in BALB/c mice against the C595 antibody. This lgG2a anti-idiotypic antibody blocked the binding of C595 to its mucin core antigen. In turn, pre-blocking of C595 with a 20 amino-acid mucin core peptide specifically inhibited binding of 911 antibody to C595. Cross-reactivity of antibody 911 was only observed against the IgM MAb, 789/91, which has the same minimum antibody-binding epitope as C595, namely, RPAP. Syngeneic and xenogeneic anti-sera against 911 antibody displayed increased binding to heptameric peptide sequences containing the motif, R P A(P). The anti-idiotypic antibody 911 therefore appears to recognize a site within or close to the binding site of the C595 antibody and thus carries an internal image of the parental mucin epitope. Consequently, the 911 idiotypic network offers a promising model system to investigate the mechanism of anti-idiotype-induced tumour immunity. 相似文献
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Mark Garton James Martin Susan New Sue Lee Nigel Loveridge John Milne David Reid Ivan Reid Simon Robins 《Clinical endocrinology》1996,44(5):563-570
OBJECTIVE Changes in calcium homeostasis and bone mass around the climacteric are poorly understood. We examined relations between endocrine factors and indices of bone mass and metabolism in healthy women approaching the menopause. DESIGN Cross-section study. PATIENTS Sixty-eight spontaneously menstruating women aged 45–55. MEASUREMENTS Bone density measured at lumbar spine (LS) and femoral neck (FN) using dual energy X-ray absorptiometry and distal non-dominant forearm using peripheral quantitative computed tomography. We recorded menstrual history, physical activity and dietary calcium, and measured serum calcium, phosphate, alkaline phosphatase, osteocalcin, vitamin D, fT3, T4, TSH, PTH, FSH and oestradiol (E2), and urinary pyridinoline (PYD) and deoxypyridinoline (DPD) excretion. RESULTS Using serum FSH level as a marker of ovarian function, 63 subjects could be classified into one of three groups: group A (serum FSH <10 U/l, n = 29), group B (10–35 U/l, n = 27) and group C (>35 U/l, n = 7). Bone density fell with declining ovarian function at the LS, FN and forearm trabecular (but not cortical) sites. Serum PTH was lower in group A vs B (mean (SD) 2.68 (0.97) vs 3.52 (1.17) pmol/l, P < 0.05), but similar to group C (2.90 (1.09) pmol/l, P = NS). Serum phosphate was elevated in group C compared to groups A and B (1.17 (0.15) vs 1.04 (0.11) and 1.05 (0.13) mmol/l, P < 0.05), and urinary PYD (61.1 (8.0) vs 50.4 (11.6) and 43.9 (8.1) μmol/mol creatinine) and DPD (15.9 (3.9) vs 12.0 (3.6) and 11.4 (3.6) μmol/mol creatinine) excretion were also increased. There were no significant differences in vitamin D metabolites or osteocalcin. Multivariate analysis suggested serum osteocalcin was positively related to physical activity and serum 1,25-dihydroxycholecalciferol levels. Serum free T3 was positively correlated with urinary DPD excretion, and inversely related to serum PTH. In all subjects, serum PTH was related to body weight (r = 0.38, P = 0.002). CONCLUSIONS Declining ovarian function before menopause is accompanied by reductions in bone mass and altered calcium metabolism. Free T3 may regulate bone resorption and indirectly modulate PTH release. 相似文献
77.
Intestinal lamina propria T cells are believed to be derived, via the systemic circulation, from gut-associated lymphoid tissue. After migration into the lamina propria, T cells are capable of luminally directed migration following the loss of surface epithelial cells. For adhesion and migration within the extracellular matrix, T cells are likely to utilize the integrin family of adhesion molecules. The aim of this study was to quantitatively and qualitatively investigate the expression of α5 and α6 integrin subunits on the surface of human T cells that: (a) migrated out of the lamina propria, (b) remained resident within the matrix and (c) were present in the circulation. In both subpopulations of CD4 and CD8-positive T cells, from both normal and inflamed (inflammatory bowel disease) colonic mucosa, there were significantly fewer α5 and α6 -positive cells than in the peripheral blood. In addition, there were significantly fewer α6 integrin molecules on the surface of CD4 and CD8-positive lamina propria T-cell subpopulations, compared with those in the circulation. Our studies suggest that, following migration into the lamina propria, there is down-regulation of α5 and α6 integrin-subunit expression on the surface of T cells. Molecules other than members of very late activation antigen-5 (VLA-5) (α5 β1 ) and VLA-6 (α6 β1 ) families of adhesion molecules are likely to be important in interactions with extracellular components in the lamina propria of normal and inflamed human colonic mucosa. 相似文献
78.
The early effects of radioiodine therapy for hyperthyroidism on biochemical indices of bone turnover
Jean M. MacLeod K. C. McHardy R. D. Harvey A. Duncan I. W. Reid P. D. Bewsher S. P. Robins 《Clinical endocrinology》1993,38(1):49-53
OBJECTIVE We investigated the early changes following radioiodine therapy for hyperthyroidism, in biochemical indices of bone synthesis and degradation, and their relationship to circulating thyroid hormone concentrations. DESIGN Prospective follow-up over the first 12 weeks after radioiodine therapy. PATIENTS Six women with clinical and biochemical evidence of hyperthyroidism. MEASUREMENTS Serum Concentrations of T4, free T3 and osteocalcin, and urinary excretion of the pyridinium cross-links, pyridinaline and deoxypyridinaline, measured before and weekly for 12 weeks after administration of radioiodine therapy. RESULTS Biochemical indices of bone metabolism were elevated prior to treatment. There was a brisk reduction in circulating thyroid hormones levels paralleled by a similar fall In pyridinlum cross-llnk excretion, which had returned to normal in five patients by the end of the study. There was a positive correlation between pyridinium cross-link excretion and thyroid hormone concentrations. There was no significant change in serum osteocalcin. CONCLUSIONS Treatment of hyperthyroidism results in prompt correction of the associated increased rate of bone collagen degradation suggesting that effective early correction of hyperthyroidism is desirable to limit its detrimental effect on skeletal mass. 相似文献
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David G. Streeter Mark Miller Thomas R. Matthews Roland K. Robins Jon P. Miller 《Biochemical pharmacology》1980,29(12):1791-1797
The mechanism by which 7-ribosyl-3-deazaguanine exerts its antibacterial effect was examined. Escherichia coli was found to contain an enzyme that exhibited the properties of a nucleoside phosphorylase and that converted 7R3DG to 3-deazaguanine (3DG, 6-aminoimidazo[4,5-c]pyridin-4(5H)-one], but no mammalian system that was examined (Erilch ascites, rat liver and human liver) was able to convert 7R3DG to 3DG. The 3DG arising from the phosphorolysis of 7R3DG was converted to 3-deaza-GMP [3DGMP, 6-amino-l-β-D-riboluranosylimidazo [4,5-c]pyridin-4(5H)-one-5′-phosphate] by the guanine phosphoribosyltransferase present in E. coli. A strain of E. coli, resistant to 7R3DG, was found to lack this enzyme and, therefore, was unable to convert 3DG to 3DGMP. 相似文献