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91.
92.
D. A. Basketter E. W. Scholes M. Cumberbatch C. D. Evans I. Kimber 《Contact dermatitis》1992,27(4):209-213
The guinea pig maximization test (GPMT) has proven to be a valuable tool for the identification of the skin sensitization potential of chemicals. The method identifies a hazard which can lead in the EC to compulsory labelling of that chemical. In the present study, data on sulphanilic acid derived from the GPMT has been compared with results from a second guinea pig assay (the cumulative contact enhancement test) and the murine local lymph node assay, both of which require only topical application of chemical. Except for the GPMT, no test identified any sensitizing activity associated with exposure to sulphanilic acid. These latter results are consistent with the experience gained from substantial human exposure in an occupational setting and from which no cases of allergic contact dermatitis to sulphanilic acid have arisen over a 20-year period. In consequence, it is questioned which test protocol in practice has given the more accurate identification of sensitization hazard relevant to man. 相似文献
93.
94.
In the past few years there have been numerous publications which have stressed the value of the dexamethasone suppression test (DST) as a diagnostic marker of endogenous depression. Our own studies in 333 psychiatric inpatients and 121 healthy subjects did not reveal a differential diagnostic use for the DST. This result is in good agreement with other results in the literature. Our data demonstrate that intervening variables such as severity of illness, weight loss, sleep disturbances, situational stress, drug and alcohol withdrawal, and the pharmacokinetics of dexamethasone have an important influence on DST results, regardless of the diagnostic classification. 相似文献
95.
聚合酶链反应和噬菌体裂解试验监测鼠疫菌的应用比较研究 总被引:2,自引:1,他引:1
应用聚合酶链反应 (PL-PCR)技术和噬菌体裂解试验同时对 80株鼠疫菌 ,1株假结核株、 1株大肠杆菌埃希氏菌进行检测并作比较。结果显示经噬菌体裂解试验 82株菌均在 18~ 2 0 h显示出噬菌斑 ,而其中 2株聚合酶链反应为阴性 ,另 80株全部为鼠疫菌特异性扩增带 ,比较清晰、典型、稳定 ,它有助于鼠疫菌快速特异诊断 相似文献
96.
Detection of linkage under heterogeneity: comparison of the two-locus vs. admixture models. 总被引:9,自引:0,他引:9
L R Goldin 《Genetic epidemiology》1992,9(1):61-66
Linkage analysis under the two-locus model and the admixture model was compared on pedigree data for a common disease stimulated under a model of genetic heterogeneity. The ascertainment of families was designed so that the samples had a large proportion of families segregating for both disease loci. The two-locus linkage analysis model did not demonstrate increased power of detecting linkage or more accurate estimates of the recombination fraction, theta than did the admixture model linkage analysis. When a sample was purposely chosen so that all of the families were segregating for both loci, then the two-locus lod score analysis was better. However, the increased power depended on assuming the correct gene frequency for the linked locus. It can be concluded that under the conditions of genetic heterogeneity examined here, testing for linkage under the admixture model is the preferred method of analysis. However, this is not a general conclusion that can apply to all two-locus disease models. 相似文献
97.
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
98.
Protective effect of different doses of terfenadine on the conjunctival provocation test 总被引:1,自引:0,他引:1
The protective effect of terfenadine on inOammatory processes following the early phase of conjunctival provocation tests by specific allergen was assessed in 24 patients suffering from seasonal allergic rhinoconjunctivitis, in a single-blind, randomized, placebo-controlled, parallel-group study. Patients were randomly assigned to four treatment groups, each being given terfenadine 60, 120, 180 mg daily, or placebo, respectively, for 7 days, out of the pollen season. Clinical severity (burning, itching, lacrimation and hyperemia), and number of inflammatory cells obtained by conjunctival scraping (neutrophils, eosinophils, lymphocytes, and monocytes) were evaluated before and after treatment. Pre-treatment with terfenadine resulted in a significantly higher allergen threshold dose than placebo (p<0.01), regardless of drug dose. Patients given terfenadine experienced a significant reduction (p<0.03) in conjunctival symptom severity, as compared with placebo, following conjunctival challenge. Accordingly, the number of inflammatory cells in terfenadine-treated patients was significantly lower (p<0.01) than in the placebo-treated after the conjunctival provocation test. The results of this study suggest that terfenadine has a significant protective effect on the early-phase cellular and clinical events of conjunctival reaction induced by allergen challenge in atopic patients. 相似文献
99.
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
100.
单纯性肥胖儿童的智力研究 总被引:4,自引:1,他引:3
本调查了114名不同肥胖程度的儿童智力状况。结果发现:患儿与正常体重儿童的智力水平没有显差异(P>0.05)。表明单纯性肥胖儿童的智力发育正常。 相似文献