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41.
血清瘦素水平的影响因素及相关性分析 总被引:7,自引:3,他引:4
目的探讨血清瘦素水平的影响因素及相关性分析.方法从2003年3~8月门诊体验人群中随机抽取标本150人,并排除糖尿病及高血压,测定FBS、血脂水平、血清瘦素水平(LEP)、胰岛素水平(INS),瘦素、胰岛素测定均采用放射免疫方法.胰岛素敏感性以敏感指数(IAI)评价.结果血清瘦素水平女性明显高于男性;相关分析显示血清瘦素水平与性别(SEX)、年龄(AGE)、体重指数(BMI)、INS显著正相关(r分别为0.429,0.329,0.249,0.322,P<0.05);与LOGIAI显著负相关(r=0.322,P<0.05),与TC,TG无明显相关;在调整年龄、BMI后,多远逐步回归分析显示血清瘦素水平仍与INS,LOGIAI显著相关.结论血清瘦素水平与TC,TG均无相关,提示高脂血症患者血清瘦素水平与正常人群比较无明显改变;血清瘦素水平与LOGIAI负相关,高瘦素水平人群胰岛素敏感性降低、存在胰岛素抵抗,提示瘦素-胰岛素轴的存在,瘦素是胰岛素抵抗的一个独立危险因素.肥胖患者存在高瘦素血症、瘦素抵抗.如果能弄清瘦素、胰岛素抵抗、肥胖之间的相互作用关系及因果关系,可能对瘦素抵抗、胰岛素抵抗相关痰病的防治有一定的意义. 相似文献
42.
K.W.E. DENSON 《International journal of laboratory hematology》1988,10(3):315-328
A more sensitive or higher concentration of rabbit brain thromboplastin does not result in greater accuracy and precision of results in oral anticoagulant therapy and is unable to mimic the PIVKA sensitivity of human brain. In terms of International Normalized Ratios the British Comparative Thromboplastin and Manchester Comparative Reagent (both now discontinued) and the Manchester Reagent had the poorest sensitivity to factor VII of all the reagents studied. It is not possible accurately to calibrate rabbit brain against human brain thromboplastin in the upper therapeutic range and beyond. 相似文献
43.
The glucose clamp technique is currently regarded as the standard test for measuring insulin sensitivity against which other methods are compared but is unsuitable for routine screening of patients outside a hospital base. There is thus a need for a simpler test to measure insulin sensitivity. We have therefore compared the glucose disappearance rate KITT in the first 15 min of the insulin tolerance test (ITT) with the M and M/I values derived from the standard euglycaemic clamp in nine normal subjects and eight subjects with Type 2 (non-insulin dependent) diabetes mellitus and coexisting obesity. All subjects underwent the ITT and euglycaemic clamp in random order. Nine subjects later had a repeat ITT to determine the reproducibility of the test. In the ITT, 0.1 U kg-1 body weight, human Actrapid insulin was given as an IV bolus and simultaneous arterialized and venous blood samples were obtained every minute for 15 min. The first order rate constant for the disappearance of glucose KITT over the period 3-15 min was taken as a measure of insulin sensitivity. The euglycaemic clamp was performed with an insulin infusion of 50 mU kg-1 h-1 for 120 min and a variable rate glucose infusion to maintain blood glucose concentration at 0.5 mmol l-1 below fasting level to minimize the effect of endogenous insulin secretion. The ratio of the mean rate of glucose infused (M, mumol kg-1 min-1) to the plasma insulin over the last 30 min of the clamp was taken as a measure of tissue sensitivity to insulin (M/I) assuming endogenous glucose output was suppressed.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
44.
Th. Büttner S. Schulz W. Kuhn A. Blumenschein H. Przuntek 《European journal of neurology》1994,1(2):153-157
Colour discrimination and visual contrast perception were investigated in 18 patients with Huntington's disease (HD) and in 18 age- and sex-matched healthy volunteers using the Farnsworth-Munsell 100 Hue test (FM) and stationary contrast targets. The mean total error score (MTES) and the partial scores for the “red-green” and the “blue-yellow” axes in the FM of the patients with HD were significantly elevated as compared to controls (MTES in HD: 113.0 ± 90.8; MTES in controls: 19.2 ± 8.8). The spatial contrast sensitivity in HD patients was normal. The colour perception dysfunction indicates that the visual system is affected in HD. The visual disorder may be related to an imbalance of certain neurotransmitters in the visual system of HD patients. Possible anatomical sites of the dysfunction responsible for colour discrimination abnormalities could be the retinal cone system and/or impaired parvocellular central visual pathways in HD. 相似文献
45.
A critical assessment of allergen component-based in vitro diagnosis in cherry allergy across Europe
A. Reuter J. Lidholm K. Andersson J. Östling M. Lundberg S. Scheurer E. Enrique A. Cistero-Bahima M. San Miguel-Moncin B. K. Ballmer-Weber Stefan Vieths 《Clinical and experimental allergy》2006,36(6):815-823
BACKGROUND: Food allergy to cherry occurs throughout Europe, typically with restricted oral reactions in the central and northern parts but with frequent systemic reactions in the Mediterranean region. Previous studies have demonstrated insufficient sensitivity of commercially available cherry extract reagents in the diagnosis of cherry allergy. OBJECTIVE: To assess the diagnostic performance of specific IgE tests based on recombinant cherry allergens in comparison with an extract-based assay and to skin prick test (SPT). A secondary objective was to analyse the frequency of systemic reactions in cherry-allergic subjects across Europe, including the largest population of LTP-sensitized subjects from central Europe studied to date. METHODS: A total of 186 subjects from central Europe and Spain were studied. Serum IgE was analysed with ImmunoCAP tests carrying rPru av 1, 3 and 4, combined and separately, and cherry extract. RESULTS: Among the central European cherry allergics, the mix of rPru av 1, 3 and 4 had a sensitivity of 95%, compared with 65% for cherry extract, and the IgE binding capacity of the recombinant mix was considerably higher. The sensitivity of the two tests was more comparable in the Spanish population, 95% and 86%, respectively. The recombinant allergen ImmunoCAP equalled SPT in terms of sensitivity and specificity. Consistent with previous reports, major geographic differences in sensitization pattern and prevalence of systemic reactions were found. A significantly higher rate of systemic reactions was found in Spanish patients sensitized to Pru av 3 whereas German patients sensitized to LTP only had oral allergy syndrome. CONCLUSIONS: The recombinant cherry allergen ImmunoCAP is a highly sensitive diagnostic tool, clearly superior to any diagnostic method based on cherry extract. Three cherry allergens are sufficient for detecting sensitization in 95% of cherry-allergic subjects. Systemic reactions are common in LTP-sensitized individuals but seem to require at least one additional causative factor. 相似文献
46.
目的了解广州地区2002年淋球菌对抗生素的耐药性及产青霉素酶淋球菌(PPNG)和高水平耐四环素淋球菌(TRNG)的流行状况。方法用琼脂稀释法测定四环素、壮观霉素、头孢三嗪和环丙沙星4种抗生素对100株淋球菌的最低抑菌浓度(MIC)及用纸片碘量法检测β-内酰胺酶。结果100株淋球菌检出PPNG 15株(15%)、TRNG 28株(28%),环丙沙星耐药率高达98%,高度耐药株(MIC≥16 mg/L)32株(32%),未发现对头孢三嗪、壮观霉素的耐药菌株,但头孢三嗪的敏感性有所下降。结论目前广州地区流行的淋球菌菌珠耐药状况仍然严重,尤以环丙沙星为甚,但对壮观霉素和头孢三嗪仍较敏感。此外,有必要持续监测球菌的耐药性。 相似文献
47.
N. P. Mikaelyan Yu. A. Knyazev G. D. Zhumagalieva E. P. Mikaelyan 《Bulletin of experimental biology and medicine》1994,117(5):457-460
Insulin-binding activity of blood cells in pregnant women is shown to vary considerably in health and in diabetes mellitus
with different forms and stages of compensation. More stable changes were observed just in erythrocytes.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N
o
5, pp. 461–464, May, 1994
Presented by Yu. A. Romanov, Member of the Russian Academy of Medical Sciences 相似文献
48.
Lasse Kanerva Maj-Len Henriks-Eckerman Tuula Estlander Riitta Jolanki Kyllikki Tarvainen 《Journal of the European Academy of Dermatology and Venereology》1994,3(2):157-168
Background Dentin-bonding systems contain sensitizing acrylates. They are increasingly used in dentistry, but only few cases of allergy have been encountered. Objective This study reports observations on eleven patients sensitized by acrylates in dentin-bonding compounds. Furthermore, the composition of dentin-bonding products was analysed and compared with the information given in the material safety data sheets. Methods Patch testing was performed to reveal allergic contact dermatitis, and chamber provocation tests to reveal possible respiratory sensitivity. Gas chromatography/mass spectrometry was used to analyse the chemical composition of the bonding products. Results The most common sensitizer in our material of eleven patients was 2-hydroxyethyl methacrylate (2-HEMA). Another putative sensitizer, BIS-GMA, used in dentin adhesives, did not cause sensitization. The typical allergic dermatitis localized to the fingertips (pulpitis). Seven of the eleven patients also developed paresthesia of the fingertips. One patient with positive patch test reactions to (meth)acrylates had pharyngitis hut no skin symptoms. One patient was sensitized because she had been patch tested with too high a concentration (undiluted) of dentin-bonding components. Material safety sheets gave inaccurate or wrong information about the contents. Conclusion Dentin-bonding acrylates are strong sensitizers, and even a single exposure may sensitize. 相似文献
49.
50.
目的探讨脑梗死患者血清高敏C反应蛋白(hsCRP)含量的变化及其临床意义。方法随机选择57例脑梗死患者,检测其高敏C反应蛋白的血清水平。观察脑梗死不同病情含量变化,并分析与患者临床神经功能缺损程度评分的相关性。结果脑梗死患者的血清hsCRP水平明显高于正常对照组(P<0.01)。脑梗死不同临床分型组间血清hsCRP水平比较,重型组明显高于中型、轻型组,差异均有统计学意义(P<0.01)。脑梗死患者血清hsCRP含量与临床神经功能缺损程度评分呈正相关(r=0.255,P<0.05)。结论血清hsCRP水平增高与脑组织受损程度有密切关系。hsCRP升高可能是脑梗死发病的一个危险因素。hsCRP升高对治疗及估计预后有指导意义。 相似文献