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141.
M Chaour P Théroux BM Gilfix L Campeau J Lespérance M Ghitescu F Gélinas BC Solymoss 《Canadian Metallurgical Quarterly》1997,8(11-12):683-688
BACKGROUND: Increased fasting serum insulin level not associated with hypoglycemia is considered to be a practical indicator of the insulin resistance syndrome, a frequent risk factor for atherosclerosis in industrialized countries. However, in most studies, insulin was measured by using antibodies which cross-react with proinsulin and 31/32, 32/33 split products of insulin. We re-examined the correlations between the insulin resistance syndrome and 'true' fasting serum insulin level. METHODS: We studied 242 post-menopausal women (age 63 +/- 8 years), a population in whom insulin resistance syndrome is particularly frequent. Serum insulin was measured by a recent specific microparticle immunoassay. RESULTS: There was a significant correlation between elevated 'true' fasting serum insulin level and various constituents of the insulin resistance syndrome, such as obesity, dyslipidemia (hypertriglyceridemia, increased apolipoprotein B and decreased high-density lipoprotein cholesterol and apolipoprotein A1 concentrations), increased serum glucose, uric acid levels, and plasminogen activator inhibitor type I concentration, as well as increased frequency of diabetes. There was also a correlation between insulin level and various manifestations of coronary artery disease: patients in the highest quartile of 'true' insulin level had significantly more entirely occluded coronary arteries than in the lowest one. Similarly, in the highest insulin quartile more patients had occluded arteries with lumen diameter stenoses greater than 50% (P < 0.05) and more of them had history of previous myocardial infarction approaching the level of significance (P = 0.0587) than in the lowest one. Most of these correlations were also noted in nondiabetic people. CONCLUSIONS: An increase of 'true' fasting serum insulin level is a useful practical index to identify patients with the insulin resistance syndrome exposed to increased risk of coronary artery disease. 相似文献
142.
通过电导率测量、pH测量、同步热分析(STA)、Tafel极化曲线法和电化学交流阻抗谱法研究了不同浓度和温度下过期药呋塞米在1 mol/L的醋酸溶液中对冷轧钢缓蚀作用。实验结果表明:过期药呋塞米在1 mol/L的醋酸溶液中对冷轧钢有较好的缓蚀效果,且缓蚀率随着缓蚀剂浓度和温度的增加而增大。该缓蚀剂在醋酸中对钢是一种抑制阴极和阳极的混合型缓蚀剂。缓蚀剂在冷轧钢表面的吸附符合Langmuir吸附等温式,其吸附是自发、物理吸附过程。同步热分析还说明了该缓蚀剂易稳定吸附在冷轧钢表面。 相似文献
143.
BM Fraga P González R Guillermo MG Hernández 《Canadian Metallurgical Quarterly》1998,61(10):1237-1241
Biotransformations of jhanol (18-hydroxymanoyl oxide) (2), jhanidiol (1beta,18-dihydroxymanoyl oxide) (3), and 1-oxo-jhanol (1-oxo-18-hydroxymanoyl oxide) (4) by the fungus Mucor plumbeus have been studied. In the incubation of 2 there exists a preference for hydroxylation at C-2(alpha) (8) and C-6(beta) (9-11) and, to a lesser degree, at C-1(alpha) (7), C-11(alpha) (6), and C-11(beta) (5 and 10). In the second substrate (3), the presence of a 1beta-hydroxyl group inhibits 6beta- or 11-hydroxylation. Epoxidation of the vinyl group constitutes the main reaction, with the positions 2alpha (14) and 3beta (15) being hydroxylated. In the incubation of 4, there was a preference for 6beta-hydroxylation (21) or epoxidation of the vinyl group (22). Other hydroxylations observed were at the 2alpha (19), 2beta (20), 3alpha (23), 3beta (24), and 11beta (18) positions. 相似文献
144.
FM Ewing IJ Deary RJ McCrimmon MW Strachan BM Frier 《Canadian Metallurgical Quarterly》1998,64(5):653-660
Acute hypoglycemia in people with type 1 (insulin-dependent) diabetes mellitus causes general impairment in cognitive performance. The effects on more specific cognitive processes are less well defined. Acute hypoglycemia has been shown to impair visual information processing in nondiabetic human subjects and has now been examined in 16 adult subjects with type 1 diabetes. All subjects had normal visual acuity and no diabetic retinopathy, and their median (range) age was 24 (18-47) years with a median (range) duration of type 1 diabetes of 8 (2-18) years and a mean (SD) HbA1c of 8.5 (1.3)%. A hyperinsulinemic glucose clamp technique was used to maintain arterialized blood glucose at 5.0 mmol l(-1), and on separate test days, either euglycemia was continued or hypoglycemia (2.6 mmol l(-1)) was induced. During each condition subjects performed tests of visual processing and cognitive function. Hypoglycemia caused a significant disruption in general cognitive ability as assessed by digit symbol (p < 0.001) and trail-making B (p < 0.05) tasks. Conventional measures of visual acuity were unaffected by hypoglycemia, but visual information processing deteriorated significantly as indexed by inspection time (p < 0.005) and visual change detection (p < 0.01). Contrast sensitivity tended to deteriorate during hypoglycemia (p = 0.06). In conclusion, hypoglycemia impairs important aspects of early visual information processing and contrast sensitivity in adults with type 1 diabetes. Further research is needed to evaluate the functional relevance of such changes for everyday tasks that require the intake of visual information at speed and under conditions of low contrast. 相似文献
145.
MR Sapoval BM Beyssen C Girardot MA Musset P Legmann O Brekke JC Gaux 《Canadian Metallurgical Quarterly》1996,51(3):210-213
In the past, interleukin-8 (IL-8) could be demonstrated within keratinocytes in normal epidermis and inflammatory skin diseases, like psoriasis and eczema. Using monoclonal antibodies, the distribution of IL-8 immunoreactivity was inversely related to the density of inflammatory infiltrate. Other in vitro observations indicated IL-8 to be a growth factor for keratinocytes. These results prompted an immunohistochemical examination of IL-8 immunoreactivity in malignant and semimalignant epithelial tumours of human skin. Whereas IL-8 could not be detected within the transformed cells of epithelial tumours or melanoma, some tumour cells within well differentiated squamous cell carcinoma and Bowen's disease showed IL-8 immunoreactivity. Thus, loss of IL-8 immunoreactivity can be a sign of malignant transformation. This indicates an important role in growth regulation as well as terminal differentiation of human keratinocytes. 相似文献
146.
147.
Cot death (sudden infant death syndrome) is one of the most common causes of death in the first year of life. Four cases with a pathological fear of cot death are presented. All the patients were depressed and in 2 cases the fear of cot death had an obsessional quality. In all cases there were complications during pregnancy (miscarriage, threatened abortion, recurrent vomiting in last trimester). In 1 case, the patient knew 3 mothers who had suffered cot deaths; in another, the infant was gravely ill in the neonatal period. Pathological fear of cot death can be recognised by the presence of two central features - overvigilance and excessive nocturnal checking of the baby's breathing. Therapeutic interventions are discussed. 相似文献
148.
149.
SM Witherspoon DL Emerson BM Kerr TL Lloyd WS Dalton PS Wissel 《Canadian Metallurgical Quarterly》1996,2(1):7-12
Galactose-1-phosphate uridyl transferase (GALT) deficiency causes classical galactosemia in humans. Mice deficient in this enzyme were created by gene targeting. GALT-deficient mice develop biochemical features similar to those seen in humans with GALT deficiency, but fail to develop the pattern of acute toxicity seen in newborns with classical galactosemia. This study suggests that alternative routes of galactose metabolism are important in the pathogenesis of galactosemia. 相似文献
150.