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991.
Increased binding of limulin to alpha 2-macroglobulin and immunoglobulin M from cystic fibrosis patients 总被引:1,自引:0,他引:1
In the present study the binding of limulin, a lectin with sialic acid specificity, to three serum glycoproteins from controls and cystic fibrosis patients was compared. alpha 2-Macroglobulin from patients with cystic fibrosis was shown to have significantly increased binding to the lectin limulin when compared to that from healthy controls (t = 3.6, p less than 0.01). The binding of limulin to immunoglobulin M (IgM) from cystic fibrosis patients was also shown to be significantly higher than the binding to IgM from controls (t = 3.6, p less than 0.01), whereas no detectable binding of fluorescein-conjugated limulin to immunoglobulin G from either cystic fibrosis patients or controls was observed. These findings support the hypothesis that the underlying inherited defect in cystic fibrosis might be an abnormal synthesis or degradation of glycoproteins and glycopeptides. 相似文献
992.
Antibodies against the 19 amino acid encephalitogenic peptide )residues 68-88) of guinea pig myelin basic protein (GPBP) were raised in Lewis (Le) rats. Anti-peptide antibodies were isolated from immune ascitic fluids by affinity chromatography using peptide 43-88-Sepharose 4B. The purified antibodies were characterized by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and isoelectric focusing. Immunoglobulin class was determined by radioimmunoassay. Anti-idiotypic (anti-ID) antibodies were raised in a rabbit using purified anti-peptide antibodies from a single rat. The results of these experiments showed antibody heterogeneity both within an individual anti-peptide antiserum and between antisera from different rats. Antibody activity was found in IgG1, IgG2, and IgE immunoglobulin classes. Isoelectric focusing revealed multiple bands within a population of purified antibodies with significant pattern variation from one antiserum to another. Idiotypic characterization showed various levels of cross-reactive idiotypes present in some sera while these were absent in others. 相似文献
993.
Autosomal recessive sudden unexpected death in children probably caused by a cardiomyopathy associated with myopathy. 总被引:1,自引:0,他引:1
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The propositus, who died suddenly at the age of 22 months, was investigated because of an unusual myopathy. Family history revealed two sisters and four cousins who had also died suddenly and unexpectedly. The finding of asymmetric septal hypertrophy by echocardiography in the propositus suggested that the cause of the sudden death in the relatives was an undetected cardiomyopathy accompanying a mild and often subclinical myopathy. The affected children were in two sibships and both sets of parents were first cousins. The mother of one sibship was the sister of the father of the other. It is suggested that a gene causes a mild autosomal recessive myopathy with cardiomyopathy that is often undiagnosed and usually ends in sudden unexpected death in the second year of life. The same gene may manifest on echocardiogram in some heterozygotes as asymmetric septal hypertrophy. 相似文献
994.
The Association Between Cigarette Smoking and Ocular Diseases 总被引:9,自引:0,他引:9
Yoram Solberg MD PhD Mordechai Rosner MD MSC Michael Belkin MA MD 《Survey of ophthalmology》1998,42(6):535-547
Tobacco smoke is composed of as many as 4,000 active compounds, most of them toxic on either acute or long-term exposure. Many of them are also poisonous to ocular tissues, affecting the eye mainly through ischemic or oxidative mechanisms. The list of ophthalmologic disorders associated with cigarette smoking continues to grow. Most chronic ocular diseases, with the possible exception of diabetic retinopathy and primary open-angle glaucoma, appear to be associated with smoking. Both cataract development and age-related macular degeneration, the leading causes of severe visual impairment and blindness, are directly accelerated by smoking. Other common ocular disorders, such as retinal ischemia, anterior ischemic optic neuropathy, and Graves ophthalmopathy, are also significantly linked to this harmful habit. Tobacco smoking is the direct cause of tobacco-alcohol amblyopia, a once common but now rare disease characterized by severe visual loss, which is probably a result of toxic optic nerve damage. Cigarette smoking is highly irritating to the conjunctival mucosa, also affecting the eyes of nonsmokers by passive exposure (secondhand smoking). The dangerous effects of smoking are transmitted through the placenta, and offspring of smoking mothers are prone to develop strabismus. Efforts should be directed toward augmenting the campaign against tobacco smoking by adding the increased risk of blindness to the better-known arguments against smoking. We should urge our patients to quit smoking, and we must make them keenly aware of the afflictions that can develop when smoke gets in our eyes. (Surv Ophthalmol 42:535–547, 1998. 相似文献
995.
This study evaluated and compared the effect of three different sedation combinations on the young dental patient: hydroxyzine alone, hydroxyzine with nitrous oxide, and nitrous oxide alone. Nineteen uncooperative children with mean age of 37 months needing at least three restorative visits were selected for this study. Crying, alertness, and general behavior were evaluated during the dental procedure. The combination of hydroxyzine and nitrous oxide was more effective than the others for the majority of the sessions in terms of controlling crying and alertness. The results in the present study indicate that the sedative effect of hydroxyzine on children's behavior is enhanced by the addition of nitrous oxide. 相似文献
996.
Captopril, but not diltiazem, favorably affects the course of early chronic renal disease in rats 总被引:1,自引:0,他引:1
E Podjarny M Rathaus J Bernheim J Shapira N Kariv A Pomeranz S Zadok J Bernheim 《Nephron》1990,55(2):196-202
The concepts that increased intracellular Ca2+ content and increased glomerular capillary pressure play an important role in the progression of chronic renal diseases has led to the suggestion that treatment with calcium-blocking agents (diltiazem; CBB) or converting enzyme inhibitors (captopril; CEI) may be indicated to prevent renal failure. We studied the effects of CCB and CEI on the early course of adriamycin (ADR) nephropathy, where glomerular pressure has been shown to be unchanged, blood pressure was only mildly elevated and renal failure incipient. Animals were studied 2, 7, 12, 16 and 20 weeks after the second injection of ADR, 2 mg/kg. In treated rats, blood pressure remained normal. At the end of the study, proteinuria and serum creatine were lower in ADR-CEI than in ADR rats (149 +/- 42 vs. 616 +/- 90 mg/day, p less than 0.01 and 0.36 +/- 0.04 vs. 0.58 +/- 0.02 mg%, p less than 0.01, respectively). ADR-CCB had values similar to those of untreated ADR rats. Mesangial expansion and focal glomerulosclerosis were present only in ADR and ADR-CCB rats, whereas in ADR-CEI rats the glomeruli were virtually normal. Glomerular 45Ca uptake was increased in ADR, decreased in ADR-CCB rats, and normal in ADR-CEI. Glomerular 6-keto PGF1 alpha and TxB2 were significantly increased in ADR rats, and both treatments decreased TxB2. The results suggest that endogenous angiotensin II is important for the early progression of glomerular injury toward renal insufficiency, while tissue Ca2+ accumulation may play an important role in more advanced phases. 相似文献
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J L Cummings S Petry L Dian J Shapira M A Hill 《The Journal of neuropsychiatry and clinical neurosciences》1990,2(3):261-267
Personality alterations were investigated in patients with dementia of the Alzheimer type (DAT), multi-infarct dementia (MID), and normal control subjects, using a standardized informant-rated personality inventory. Personality alterations were observed in all patients, and the two diagnostic groups exhibited many similar behavioral alterations. DAT patients had significantly greater alterations in maturity and exhibited less personal control compared with the MID patients; the latter manifested more apathy and remained more affectionate and easy-going. Few correlations were found between the severity of dementia and the magnitude of behavioral changes. Personality alterations are an important and consistent aspect of the phenomenology of dementing disorders. 相似文献