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71.
72.
BM Hausen 《Canadian Metallurgical Quarterly》1980,116(3):327-328
An eczematous eruption developed on the hands and forearms of a 68-year-old man after frequent contact with homebred specimens of the lady slipper Paphiopedilum haynaldianum. Patch tests with leaves, petals, and stems, as well as with two quinones isolated from the plant by thin-layer chromatography, gave strongly positive reactions. The results demonstrated that the recurrent skin lesions were the expression of an allergic contact dermatitis due to the quinoid constitutnets, which are the main contact allergens in this orchid species. 相似文献
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IP Nikitin AV Shabalin EN Ermakova AV Kytmanov NV Golyshev BM Rogachevski? SV Motorin 《Canadian Metallurgical Quarterly》1996,74(5):29-31
The study compared diagnostic potential of magnetocardiography (MCG), electrocardiography (ECG) and echocardiography (echo-CG) in 18 patients with arterial hypertension (AH). 32 healthy males served as control. Elements of MCG from normal subjects have been analyzed morphologically in 36 points of precordial leads. Left ventricular hypertrophy was registered at echo-CG, MCG, ECG in 11 (61%), 16 (84%) and 7 (34%) of the AH patients, respectively. Left atrial hypertrophy was discovered primarily by echo-CG and MCG. Defects in ventricular repolarization were recorded by MCg in 7 (39%) patients basing on MCG, echo-CG and rarely ECG signs of left ventricular hypertrophy. MCG is recommended as an effective tool in diagnosis of "hypertensive heart". 相似文献
75.
Isolation of porcine circovirus-like viruses from pigs with a wasting disease in the USA and Europe 总被引:3,自引:0,他引:3
GM Allan F McNeilly S Kennedy B Daft EG Clarke JA Ellis DM Haines BM Meehan BM Adair 《Canadian Metallurgical Quarterly》1998,10(1):3-10
Sinus pericranii is an anomalous extracranial vascular malformation that is in continuity with the intracranial dural venous sinuses. Five case reports, three congenital and two traumatic, are described. Clinical management, including evaluation, diagnosis, and treatment, is discussed. Awareness of this entity by plastic surgeons will allow for earlier diagnosis and appropriate surgical management, resulting in decreased risk of complications. 相似文献
76.
SJ Kish I Lopes-Cendes M Guttman Y Furukawa M Pandolfo GA Rouleau BM Ross M Nance L Schut L Ang L DiStefano 《Canadian Metallurgical Quarterly》1998,55(10):1299-1304
BACKGROUND: Although the abnormal gene products responsible for several hereditary neurodegenerative disorders caused by repeat CAG trinucleotides have been identified, the mechanism by which the proteins containing the expanded polyglutamine domains cause cell death is unknown. The observation that several of the mutant proteins interact in vitro with the key glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) suggests that interaction between the different gene products and GAPDH might damage brain neurons. OBJECTIVE: To measure the activity of GAPDH in postmortem brain of patients with CAG repeat disorders. PATIENTS AND METHODS: Activity of GAPDH was measured in morphologically affected and unaffected brain areas of patients with 4 different CAG repeat disorders (Huntington disease, spinocerebellar ataxia 1 [SCA1], SCA2, and SCA3-Machado-Joseph disease), in brains of patients with Friedreich ataxia (a GAA repeat disorder) and Alzheimer disease, and in brains of matched control subjects. RESULTS: Brain GAPDH activity was normal in all groups with the exception of a slight but statistically significant region-specific reduction in the patients with Huntington disease (caudate nucleus, -12%) and Alzheimer disease (temporal cortex, -19%). CONCLUSION: The presence of the polyglutamine-containing proteins in CAG repeat disorders does not result in substantial irreversible inactivation or in increased activity of GAPDH in human brain. 相似文献
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The effects of endurance run training on Na+-dependent Ca2+ regulation in rat left ventricular myocytes were examined. Myocytes were isolated from sedentary and trained rats and loaded with fura 2. Contractile dynamics and fluorescence ratio transients were recorded during electrical pacing at 0.5 Hz, 2 mM extracellular Ca2+ concentration, and 29 degreesC. Resting and peak cytosolic Ca2+ concentration ([Ca2+]c) did not change with exercise training. However, resting and peak [Ca2+]c increased significantly in both groups during 5 min of continuous pacing, although diastolic [Ca2+]c in the trained group was less susceptible to this elevation of intracellular Ca2+. Run training also significantly reduced the rate of [Ca2+]c decay during relaxation. Myocytes were then exposed to 10 mM caffeine in the absence of external Na+ or Ca2+ to trigger sarcoplasmic reticular Ca2+ release and to suppress cellular Ca2+ efflux. This maneuver elicited an elevated steady-state [Ca2+]c. External Na+ was then added, and the rate of [Ca2+]c clearance was determined. Run training significantly reduced the rate of Na+-dependent clearance of [Ca2+]c during the caffeine-induced contractures. These data demonstrate that the removal of cytosolic Ca2+ was depressed with exercise training under these experimental conditions and may be specifically reflective of a training-induced decrease in the rate of cytosolic Ca2+ removal via Na+/Ca2+ exchange and/or in the amount of Ca2+ moved across the sarcolemma during a contraction. 相似文献
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Hepatocyte growth factor/scatter factor (HGF/SF) treatment of the Madin-Darby canine kidney epithelial cell line causes scattering of cells grown in monolayer culture and the formation of branching tubules by cells grown in collagen gels. HGF/SF causes prolonged activation of both the mitogen-activated protein (MAP) kinase extracellular signal-regulated kinase 2 (ERK2) and the phosphoinositide 3-OH kinase (PI 3-kinase) target protein kinase B (PKB)/Akt; inhibition of either the MAP kinase pathway by the MAP kinase/ERK kinase inhibitor PD98059 or the PI 3-kinase pathway by LY294002 blocks HGF/SF induction of scattering, although in morphologically distinct ways. Expression of constitutively activated PI 3-kinase, Ras, or R-Ras will cause scattering, but activated Raf will not, indicating that activation of the MAP kinase pathway is not sufficient for this response. Downstream of PI 3-kinase, activated PKB/Akt and Rac are both unable to induce scattering, implicating a novel pathway. Scattering induced by Ras or PI 3-kinase is sensitive to PD98059, as well as to LY294002, suggesting that basal MAP kinase activity is required, but not sufficient, for the scattering response. Induction of MDCK cell tubulogenesis in collagen gels by HGF/SF is inhibited by PD98059; expression of activated Ras and Raf causes disorganized growth in this system, but activated PI 3-kinase or R-Ras causes branching tubule formation similar to that seen with HGF/SF treatment. These data indicate that multiple signaling pathways acting downstream of Met and Ras are needed for these morphological effects; scattering is induced primarily by the PI 3-kinase pathway, which acts through effectors other than PKB/Akt or Rac and requires at least basal MAP kinase function. Elevated PI 3-kinase activity induces tubulogenesis, but total inhibition and excess activation of the MAP kinase pathway both oppose this effect. 相似文献