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51.
T MacNeil S Feighner DL Hreniuk JF Hess LH Van der Ploeg 《Canadian Metallurgical Quarterly》1997,75(6):735-740
OBJECTIVE: To examine the incidence of first diagnosis of invasive squamous cell carcinoma (SCC) of the skin over time. DESIGN: Retrospective, population-based incidence study. SETTING: Enumerated, geographically isolated, semiurban population served by the Mayo Clinic and its affiliated hospitals and the Olmsted Medical Center, including its affiliated hospital in Rochester, Minn. METHODS: Using the Rochester Epidemiology Project databases that capture virtually all medical care provided to the residents of Rochester, we identified and reviewed records of all documented residents in whom histologically proven, invasive SCC of the skin was first diagnosed between 1984 and 1992. Age and sex stratum-specific rates were calculated, and age-adjusted rates observed over time for individuals aged 35 years or older were analyzed using Poisson regression. Adjusted rates were compared with the results of other studies. RESULTS: Review of 1630 records identified 511 incidence cases of SCC. Tumors located on the head and neck accounted for 66.4% of tumors in females and 72.9% in males. The annual age- and sex-specific incidence rates per 100,000 increased from 0 cases among males aged 0 to 14 years to 1286.0 cases among males aged 85 years or older. Over time, the annual age-adjusted incidence rates per 100,000 females rose from 46.5 (95% confidence interval [CI], 32.4-60.6) for the 1984 to 1986 period to 99.6 (95% CI, 80.4-118.7) for the 1990 to 1992 period and were 71.2 (95% CI, 61.7-80.8) overall. The corresponding rates for males were 125.9 (95% CI, 95.3-156.4), 191.0 (95% CI, 156.9-225.0), and 155.5 (95% CI, 137.0-174.0). The age- and sex-adjusted SCC incidence rates for the period from 1987 to 1989 and 1990 to 1992 exceeded those for the period from 1984 to 1986 (P = .03 and P < .001, respectively). Our age-adjusted rates for SCC were within the ranges seen in other white populations from temperate climates. CONCLUSION: The frequencies of first diagnosis of SCC are increasing at rates beyond those explainable by demographic shifts alone. 相似文献
52.
Immunoglobulins and transient paraproteins in sera of patients with the Wiskott-Aldrich syndrome: a follow-up study 总被引:1,自引:0,他引:1
J Radl LH Dooren A Morell F Skvaril JM Vossen CH Uittenbogaart 《Canadian Metallurgical Quarterly》1976,25(2):256-263
Immunoglobulin levels of individual classes and IgG subclasses and the occurrence of homogeneous immunoglobulins--paraproteins--were studied longitudinally in the sera of three patients with the Wiskott-Aldrich syndrome; Common findings in all three patients were great variations in the immunoglobulin levels, restricted heterogeneity of the immunoglobulins, the frequent appearance of transient homogeneous immunoglobulins and the presence of serum antibodies against bovine milk proteins. A partial and selective deficiency involving mainly the T immune system is postulated as an explanation for these findings. 相似文献
53.
LM Notterpek PN Bullock S Malek-Hedayat R Fisher LH Rome 《Canadian Metallurgical Quarterly》1993,36(6):621-634
Myelin deposition and maintenance are critical to proper function of the mammalian nervous system. Previous investigations of myelination in the central nervous system (CNS) were hampered by the lack of an in vitro system that can faithfully reproduce in vivo events yet is amenable to biochemical investigation. We have developed a procedure, based on organotypic cultures, which permits efficient preparation of large numbers of cerebellar slice cultures that can be easily manipulated. Cultures have been examined to document myelination biochemically (by incorporation of [35S]sulfate into sulfolipids), immunohistochemically (by labeling the myelin components myelin basic protein and galactocerebroside), and morphologically (by both light and electron microscopy). We tested the effects of biologically active peptides and antibodies on myelination in the thin slices. The results indicate that the cultures provide an in vitro system that can be used to examine specific cellular events that occur during CNS myelination. 相似文献
54.
Absorbable buttons made from fibrin (Bioplast buttons) have been used to facilitate liver biopsy or to control haemorrhage from the liver in 3 dogs and 14 patients. The buttons are easy to use, effective, and readily absorbed. 相似文献
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WR Webb LH Harrison FR Helmcke A Camino-Lopez NA Munfakh HA Heck PV Moulder 《Canadian Metallurgical Quarterly》1997,64(5):1489-1491
Transesophageal echocardiographic studies were used to monitor the presence of air bubbles in the heart after open heart operations. After cardiac valvular procedures all 22 patients managed with careful deairing procedures had persistence of air bubbles for at least 30 minutes and usually for 45 minutes. In 56 patients with CO2 field flooding, all foam disappeared in less than 1 minute in 48 patients and the remaining 8 had complete disappearance in 1 to 24 minutes. These observations demonstrate the ineffectiveness of the usual deairing maneuvers and the effectiveness of CO2 field flooding in displacing air. 相似文献
59.
OBJECTIVE: Vasodilation by beta-adrenergic receptors of smooth muscle cells appears to be impaired early after the onset of hypercholesteremia. The aim of this study was to analyze the modulation of beta-adrenergic receptor density and adenylyl cyclase activity in the presence of moderately elevated concentrations of LDL. The effects of beta 1- and beta 2-adrenergic receptor antagonists on LDL-induced receptor changes were studied. METHODS AND RESULTS: Media explants of porcine coronary arteries were incubated with moderately elevated LDL concentrations (0.7-3.9 mmol/l). The density of beta-adrenergic receptors was determined in plasma membranes using the radioligand [125I]iodocyanopinodolol. LDL (3.9 mmol/l) resulted in a decrease of beta-adrenergic receptor density (control 137 +/- 5 vs. 89 +/- 7 fmol/mg protein, P < 0.01). After removal of LDL and cultivation for an additional 3 days beta-adrenergic receptors increased to 129 +/- 5 fmol/mg. In the presence of the beta 1- or beta 2-adrenergic receptor antagonists the LDL-mediated decrease was inhibited. Addition of metoprolol after 3 days of LDL incubation caused a restoration of receptor density. The basal, isoproterenol- and forskolin-stimulated adenylyl cyclase activities were increased after LDL incubation by 180, 110 or 80%, respectively. CONCLUSION: Moderately elevated LDL levels decreased beta-adrenergic receptor density while adenylyl cyclase activity was simultaneously increased. beta 1- or beta 2-adrenergic receptor antagonists prevented this receptor decrease and might preserve the beta-adrenergic receptor density in the presence of moderately elevated LDL levels. 相似文献
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