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991.
MC Dalakas 《Canadian Metallurgical Quarterly》1997,126(9):721-730
High-dose intravenous immune globulin (IVIg) has emerged as an important therapy for various neurologic diseases. Different interpretations of clinical trial results; the expected benefit of IVIg compared with that of alternate therapies; and issues about IVIg's safety, cost, and mechanisms of action have raised concern and uncertainty among practitioners. To clarify these areas, this paper examines the clinical, serologic, and immunologic data on more than 110 patients with various autoimmune neurologic diseases who received IVIg during the past 6 years at the National Institute of Neurological Disorders and Stroke. It also reviews work by other investigators on the efficacy, risks, benefits, and mechanisms of the action of IVIg in these diseases. In controlled clinical trials, IVIg has been effective in treating the Guillain-Barré syndrome, multifocal motor neuropathy, chronic inflammatory demyelinating polyneuropathy, and dermatomyositis. In other controlled or open-label trials and case reports, IVIg produced improvement in several patients with the Lambert-Eaton myasthenic syndrome and myasthenia gravis but had a variable, mild, or unsubstantiated benefit in some patients with inclusion-body myositis, paraproteinemic IgM demyelinating polyneuropathy, certain intractable childhood epilepsies, polymyositis, multiple sclerosis, optic neuritis, and the stiff-man syndrome. The primary adverse reaction was headache; aseptic meningitis, skin reactions, thromboembolic events, and renal tubular necrosis occurred rarely. The most relevant immunomodulatory actions of IVIg, operating alone or in combination, are inhibition of complement deposition, neutralization of cytokines, modulation of Fc-receptor-mediated phagocytosis, and down-regulation of autoantibody production. Therapy with IVIg is effective for certain autoimmune neurologic diseases, but its spectrum of efficacy has not been fully established. Additional controlled clinical trials are needed. 相似文献
992.
Several nonsurgical approaches to the treatment of postradiation proctitis have been described, but no effective conservative treatment has yet been established. As an alternative to the usual treatment, three cases of chronic postradiation proctitis with hemorrhage were successfully treated with oral administration of sucralfate, with resultant decreased bleeding in long term follow-up period. Oral sucralfate may provide a novel approach to the treatment of intractable postradiation proctitis. 相似文献
993.
DJ Stewart R Goel MC Cripps S Huan J Yau S Verma 《Canadian Metallurgical Quarterly》1997,15(4):267-277
BACKGROUND: Chemotherapy resistance is probably multifactorial; hence, we assessed the feasibility of adding to carboplatin 6 concurrent resistance modulators in 53 patients with resistant cancers. METHODS: Pentoxifylline and dipyridamole were added to carboplatin 400 mg/m2 in cohort 1, and metronidazole was also given in cohort 2. Mannitol and saline were administered in each cohort with the theoretical objective of improving carboplatin delivery to tumors by reducing blood viscosity. Because of excessive toxicity in cohort 2, cohort 3 received the same modulators as in cohort 2 but with a reduced dose of carboplatin (200 mg/m2). Subsequent patients had the following drugs added to those in the previous cohort: novobiocin (cohort 4), tamoxifen (cohort 5), ketoconazole (cohort 6). Cohort 7 patients received the 6 cohort 6 modulators along with carboplatin 300 mg/m2. RESULTS: Thrombocytopenia was excessive in early cohorts with a carboplatin dose of 400 mg/m2, but was minimal at lower doses. Other toxicity was generally tolerable and reversible, particularly at carboplatin doses < or = 300 mg/m2, although gastrointestinal and neurological toxicity tended to worsen as additional modulators were added. No major responses (but 4 minor responses) were seen in this patient population with heavily pretreated or primarily resistant cancers. CONCLUSIONS: Acceptable doses for phase II studies are carboplatin 300 mg/m2, 20% mannitol 250 ml plus normal saline 500 ml over 1 hr prior to carboplatin, pentoxifylline 700 mg/m2/day p.o. from 3 days before carboplatin to cessation of therapy, dipyridamole 100 mg/m2 p.o. q6h x 6 days starting 24 hr before carboplatin, metronidazole (750 mg/m2 p.o. 12 hr and immediately before, and 24 hr after carboplatin; 250 mg/m2 suppository p.r. 12 hr and immediately before, and 6 and 24 hr after carboplatin; and 500 mg/m2 i.v. right after carboplatin), novobiocin 600 mg/m2 p.o. q12h x 6 days starting 24 hr before carboplatin, and tamoxifen 100 mg/m2/day plus ketoconazole 700 mg/m2/day x 3 days starting the day before carboplatin, with oral dexamethasone and ondansetron as antimetics. 相似文献
994.
995.
LC Rump M Riess E Schwertfeger MC Michel C Bohmann P Schollmeyer 《Canadian Metallurgical Quarterly》1997,29(5):656-661
The aim of our study was to characterize functionally prejunctional neuropeptide Y (NPY) receptors in human and rabbit renal cortex, as well as in human right atrium. Segments of human atrial appendages and of human and rabbit renal cortex were preincubated with [3H]noradrenaline, superfused with Krebs-Henseleit solution and stimulated electrically in superfusion chambers. The stimulation-induced outflow of radioactivity was taken as an index of endogenous noradrenaline release. The effects of subtype-selective NPY analogs on the stimulation-induced noradrenaline release were studied. NPY, its endogenous analog, peptide YY, and its C-terminal fragment, NPY13-36, but not its analog, [Leu31,Pro34]NPY, concentration dependently (1-100 nM) inhibited [3H]noradrenaline release in all tissues studied. NPY-induced inhibition of [3H]noradrenaline release in human and rabbit kidney was abolished by pretreatment with pertussis toxin. We conclude that prejunctional inhibition of noradrenaline release in human heart and human and rabbit kidney occurs through NPY receptors of the Y2 subtype, which appear to couple to a pertussis toxin-sensitive G protein. 相似文献
996.
A Pala F Padula M Barteri M Benagiano MC Gaudiano M Moro G Benagiano 《Canadian Metallurgical Quarterly》1997,704(1-2):25-34
The method presented can easily produce milligram amounts of glycodelin from pregnancy endometrium, with a 19% yield. It involves anion-exchange chromatography, gel permeation and chromatofocusing; it results in one stainable band at Mr 28,000 after sodium dodecyl sulphate-polyacrylamide electrophoresis, as well as after immunoblot analysis, performed using an affinity-purified IgG fraction from an antiserum against glycodelin. In spite of this, the corresponding gel isoelectric focusing pattern gives four stainable bands with pI values between 4.55 and 5.2. Western immunoblot analysis of tissue extracts indicates the presence of glycodelin epitopes associated with materials heavier than the native protein. Circular dichroism spectra of the highly purified protein in water solutions indicate a large amount of beta-sheet conformation, whereas those obtained with different proportions of 2-propanol in water, show an increased proportion of alpha-helix conformation. 相似文献
997.
TR Kwapil MB Miller MC Zinser J Chapman LJ Chapman 《Canadian Metallurgical Quarterly》1997,106(3):491-495
The authors compared college students identified by high scores on the Magical Ideation Scale (M. Eckblad & L. J. Chapman, 1983) and the Revised Social Anhedonia Scale (MagSoc; n = 28; M. Eckblad, L. J. Chapman, J. P. Chapman, & M. Mishlove, 1982) with control participants (n = 20) at a 10-year follow-up assessment in an attempt to replicate L. J. Chapman, J. P. Chapman, T. R. Kwapil, M. Eckblad, and M. C. Zinser's (1994) report of heightened psychosis proneness in MagSoc individuals. The MagSoc group exceeded the control group on severity of psychotic-like experiences; ratings of schizotypal, paranoid, and borderline personality disorder symptoms; and rates of mood and substance use disorders. Two of the MagSoc participants but none of the control participants developed psychosis during the follow-up period (a nonsignificant difference). Consistent with L. J. Chapman et al.'s findings, the groups did not differ on rates of personality disorders or relatives with psychosis. 相似文献
998.
MC Minnema H ten Cate EJ van Beek A van den Ende CE Hack DP Brandjes 《Canadian Metallurgical Quarterly》1997,77(6):1164-1167
Previous investigations suggested that heparin administration to humans enhances the tissue type plasminogen activator (tPA) levels in blood, but it remains uncertain whether this effect induces fibrinolysis. We studied the effect of therapeutic levels of heparinization on plasma markers for fibrinolysis in patients suspected of pulmonary embolism (PE). Blood samples were taken from 49 consecutive patients; 28 had confirmed PE, 21 had PE excluded. On admission, the plasma levels of plasmin-alpha 2antiplasmin complexes and D-dimer were significantly higher in the patient group with PE compared to those in whom PE was excluded. After heparinization the tPA levels increased in both groups, showing that this effect was not dependent on the initial level of activity of fibrinolysis. In spite of this increment in tPA levels, the concentrations of plasmin-alpha 2antiplasmin complexes and D-dimer decreased. In conclusion, although heparinization in patients with or without pulmonary embolism does lead to elevated tPA:Ag levels, this is not accompanied by enhanced fibrinolysis. 相似文献
999.
1000.
The introduction of helical computed tomography (CT) has resulted in improved quality of multiplanar reformations and three-dimensional reconstructions in the chest and abdomen and has made CT angiography a clinical reality. These imaging techniques are useful for evaluating the urinary tract, adding a new dimension to its display, resulting in improved diagnosis of renal and perirenal disease. This article reviews the indications and techniques utilized for multiplanar and three-dimensional CT for urology. The advantages and limitations are discussed, and normal and pathologic findings in the urinary tract illustrated. 相似文献