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81.
Richard O. Shillaker Graham M. Bell John T. Hodgson Michael D. J. Padgham 《Archives of toxicology》1989,63(4):283-288
Current European Community (Annex V) guidelines recommend the use of 20 test animals in the guinea pig maximisation test for skin sensitisation. The suitability, for classification and labelling purposes, of reducing the number of test animals has been examined by analysing the results of 40 studies submitted to the Health and Safety Executive, and by the use of a mathematical model. Our results suggest that in most cases an experiment with ten test animals can be used to determine satisfactorily whether a substance should be labelled with the risk phrase may cause sensitisation by skin contact. However, serious consideration should be given to the need for additional investigation if two or three of the ten test animals show a sensitisation response. The highest nonirritant concentration of a substance should be used at challenge. Clearer guidance in Annex V on evaluating challenge responses would be beneficial. 相似文献
82.
M.-H. Roy-Gagnon R. A. Mathias M. D. Fallin S. H. Jee K. W. Broman A. F. Wilson 《Annals of human genetics》2008,72(1):115-125
The Regression of Offspring on Mid-Parent (ROMP) method is a test of association between a quantitative trait and a candidate locus. ROMP estimates the trait heritability and the heritability attributable to a locus and requires genotyping the offspring only. In this study, the theory underlying ROMP was revised (ROMPrev ) and extended. Computer simulations were used to determine the type I error and power of the test of association, and the accuracy of the locus-specific heritability estimate. The ROMPrev test had good power at the 5% significance level with properly controlled type I error. Locus-specific heritability estimates were, on average, close to simulated values. For non-zero locus-specific heritability, the proposed standard error was downwardly biased, yielding reduced coverage of 95% confidence intervals. A bootstrap approach with proper coverage is suggested as a second step for loci of interest.
ROMPrev was applied to a study of cardiovascular-related traits to illustrate its use. An association between polymorphisms within the fibrinogen gene cluster and plasma fibrinogen was detected (p < 0.005) that accounted for 29% of the estimated fibrinogen heritability. The ROMPrev method provides a computationally fast and simple way of testing for association and obtaining accurate estimates of locus-specific heritability while minimizing the genotyping required. 相似文献
ROMP
83.
目的探讨血清谷氨酰转肽酶(GGT)含量变化在慢性乙型肝炎(CHB)不同程度肝脏病理损害中的变化规律及临床意义。方法测定70例CHB患者血清ALT、AST、GGT水平,同时行肝活体组织检查,对肝脏进行炎症分级和纤维分期。分析ALT、AST、GGT与CHB之间的关系。结果(1)ALT、AST、GGT随炎症程度和纤维化程度的上升而上升,但到G4和s4后则下降。GGT随ALT、AST的升高而升高,ALT、AST和GGT的相关系数分别为:0.322、0.328(P〈0.05)。在保肝治疗后,ALT较快降至正常且GGT保持在一个较低水平的为轻度CHB,而随着ALT下降,GGT仍持续在一个较高水平的为中度及重度CHB,其中重度CHB的GGT水平有所波动。结论血清GGT比ALT、AST更准确的反映肝脏的炎症程度,GGT的活动度给临床判断慢乙肝的炎症提供了重要的判断依据。 相似文献
84.
目的 探讨终末期肝病模型(MELD)评分评估肝储备功能在原发性肝癌合并肝硬化脾功能亢进中确定手术适应证的应用价值.方法 对2001年1月至2007年1月间行肝癌切除联合脾切除(联合术)治疗的40例原发性肝癌合并肝硬化脾功能亢进患者的临床资料进行回顾性分析.通过MELD评分与Child-Pugh分级比较,结合临床资料及术后并发症分析,确定这一方法在评估肝储备功能中的作用.结果 同一Child-Pugh分级的患者MELD评分结果并不一致,在各级别间有交错现象.术后发生肝功能衰竭组(6例)的MELD评分均值为(24.6±6.6).未发生肝功能衰竭组(34例)的MELD评分均值为(16.3±8.5),差异有统计学意义(P<0.05).根据MELD评分分为A组16例(MELD评分<10),B组17例(MELD评分10-20),C组7例(MELD评分>20).A组术后肝功能衰竭发生率为0,B组为11.8%(2/17),C组为57.1%(4/7),差异有统计学意义(P<0.05).根据Child-Pugh分级分为Ⅰ级26例,Ⅱ级14例.Ⅰ级术后肝功能衰竭发生率为15.4%(4/26),Ⅱ级为14.3%(2/14),差异无统计学意义(P>0.05).结论 MELD评分能够较为客观地反映肝储备功能,对外科术式的选择、手术时机的确定有一定的参考作用. 相似文献
85.
术后认知功能障碍(POCD)定义为术后通过反复多次神经心理测试,患者的基本认知功能出现不同程度的损害。而早期术后认知功能及精神障碍更多见于老年患者。虽然POCD多见于心脏手术术后,但非心脏手术后发生POCD亦不少见,老年患者(年龄大于65岁)行心脏手术或非心脏手术,术后1周POCD的发生率分别为50%及26%。POCD的高危因素包括:高龄、术前认知受损以及酗酒等。POCD影响生活质量,加重社会负担并干扰药物治疗效果,延长患者住院周期。有必要深入的研究POCD的病因和神经功能保护的策略。 相似文献
86.
R. Paschke I. Harsch B. Schlote I. Vardarli L. Schaaf S. Kaumeier J. Teuber K. H. Usadel 《Journal of molecular medicine (Berlin, Germany)》1990,68(19):942-950
Summary Although the psychological disturbances accompanying Graves' disease are well known, the time required for normalisation of these disturbances during antithyroid drug treatment is not known. Therefore sequential psychological testing during the course of Graves' disease was done. There are also contradictory results concerning the possible correlation of neurophysiological and psychological test results during the course of Graves' disease with thyroid hormone values. Finally, psychological disturbances have been proposed as possible etiologic factors in Graves' disease.In our study, a significant decrease in anxiety and irritability could be observed at the time euthyroidism was achieved. Self-evaluations of depressivity, activity, exhaustion, well-being, extraversion, introversion, and the ability to concentrate changed 1 or 2 months after euthyroidism was induced. Similar test results could be observed after induction of euthyroidism by antithyroid drugs and subtotal thyroid resection. Therefore the mode of therapy does not seem to influence the course of normalisation of psychological parameters.In contrast to other investigations there was hardly any correlation between thyroid hormone values and psychological test results or the ability to concentrate. Nontheless, patients with Graves' disease showing high scores for depression and anxiety exhibit abnormal peripheral helper/suppressor T-lymphocyte relations. Furthermore, patients suffering from Graves' disease tend to be more anxious than controls. It remains to be determined whether an increased susceptibility to psychological disturbances has led to these alterations of lymphocyte subsets in Graves' disease patients with severe depression and anxiety.Supported by SFB 258 相似文献
87.
Background: Beta-2 agonists are potent inhibitors of mast cell degranulation in vitro. Intradermally injected they also inhibit mast cell activation in human skin in vivo. To what extent orally administered 2-agonists inhibit mast cell degranulation and allergic skin responses in vivo in daily recommended doses remains unclear.Purpose: The main purpose was to study the effects of oral administered terbutaline and bambuterol on allergen- and codeine-induced histamine release and skin responses in intact human skin in vivo. In addition, control studies were carried out with intradermally injected terbutaline.Methods: Ten allergic subjects were randomized to receive bambuterol (10 mg tablets twice daily), terbutaline (7.5 mg controlled release tablets twice daily) and corresponding placebo for 5 days with a washout phase of 3 days between treatments in a double-blind, double-dummy, cross-over trial. The patients were studied at the fifth day of each regimen, i.e. at day 5, 13, and 21. Allergen- and codeine-induced histamine release was measured by microdialysis technique. Wheal and flare reactions to allergen, codeine, and histamine were measured planimetrically. Measurements were performed in the morning on day 5 on each regimen before medication and for additional 5 h after administration of the morning dose. In a separate series of experiments in another 10 allergic patients, 1–1,000 nM (0.05–50 pmoles) of terbutaline was injected intradermally for measurement of histamine release, prostaglandin D2 (PGD2) synthesis and skin responses.Results: Neither orally administered terbutaline nor bambuterol significantly reduced allergen- or codeine-induced histamine release. Flare reactions to allergen, codeine and histamine remained unaffected which was also the case for the majority of the wheal reactions. In comparison, intradermally injected terbutaline significantly reduced allergen-induced histamine release, PGD2 synthesis, and skin reactions. Codeine-induced histamine release remained unaffected. Terbutaline significantly reduced flare reactions to codeine and histamine with no effect on wheal reactions.Conclusions: Terbutaline, in micromolar concentrations, was a potent inhibitor of immediate allergic skin reactions primarily due to inhibition of mast cell degranulation. However orally administered terbutaline, as the active drug itself or released from its pro-drug bambuterol, did not inhibit mast cell activation or allergic skin responses. Received 28 January 2003; returned for revision 7 March 2003; accepted by M. Parnham 29 April 2003 相似文献
88.
Aron J. Murphy Greg J. Wilson John F. Pryor 《European journal of applied physiology》1994,69(3):250-257
The purpose of this investigation was to develop a new test of muscle function, termed the isoinertial force-mass relationship, and to determine its relationship to dynamic physical performance in comparison to an isometric test. A group of 13 trained subjects performed an isometric, and a series of iso-inertial maximal upper body tests, in a bench press movement at loads of 30%, 60%, 100% (concentric) and 100%, 130% and 150% (eccentric) of maximum. Vertical forces exerted throughout the movement were recorded by a force plate. In addition, the subjects performed the following three performance tests: a maximal bench press, a seated shotput, and two drop bench-press throws from a height of 0.25 m, with loads of 10 kg and 30% of maximum. Correlation analysis demonstrated that in each instance the iso-inertial force mass tests were the best predictors of performance (r=0.78–0.88) with both contraction type and mass specific effects apparent. Maximal isometric force and rate of force development were significantly related to some performance variables (r=0.22–0.78). However, for all the performance movements assessed, the iso-inertial test modality recorded the highest relationship to performance. The difference in the relationship between performance and iso-inertial and isometric test modalities was particularly evident in the light load dynamic performance of the seated shotput (r=0.86 vsr=0.38, respectively). These results are explained in part by the neural and mechanical differences between iso-inertial and isometric muscle actions and their respective specificity to dynamic physical performance. 相似文献
89.
BACKGROUND: Food atopy patch tests (APTs) are considered a useful tool for the diagnosis of food allergy. Hypersensitivity to peanuts has not been investigated by means of APTs so far. METHODS: APTs and skin prick tests (SPTs) with peanuts were performed in 136 atopic dermatitis (AD) patients. Relevance of positive and negative responses to these tests was assessed by repeated open challenges with peanuts. RESULTS: Nine percent of our AD patients reacted to the challenge. Positive responses to APTs were recorded in 19% of the patients, whereas in 12% positive SPTs were observed. APTs were more frequently positive in subjects with eczematous responses after challenge with respect to those with urticarial reactions. SPT reactivity proved to be higher in patients above 12 years of age, whereas APT positivity was more frequent in children under 6 years. APT sensitivity proved significantly higher than SPT sensitivity, in particular in children under 12 years of age. On the contrary, SPT specificity and positive predictive value were significantly higher with respect to those of APT in the age group of subjects under 6 years of age. CONCLUSIONS: Our data suggest that APTs with peanuts may represent a useful integration to standard testing modalities employed for the diagnosis of peanut allergy in AD patients. 相似文献
90.
Svendsen UG, Frølund L, Heinig JH, Madsen F, Nielsen NH, Weeke B. High-dose inhaled steroids in the management of asthma. A comparison of the effects of budesonide and beclomethasone dipropionate on pulmonary function, symptoms, bronchial responsiveness and the adrenal function.
The efficacy of budesonide (800 μg b.d.) and beclomethasone dipropionate (750 μg b.d.) in controlling the symptoms of asthma, pulmonary function, bronchial responsiveness to histamine, and adrenal function, was assessed in a double-blind, double-dummy cross-over study of 36 adult chronic asthmatic patients. The patients, the majority of whom were assessed to be affected to a severe degree, were insufficiently controlled in their current regimen of inhaled steroids and/or inhaled and oral bronchodilators. A 2 weeks baseline period preceded 6 weeks of treatment with each of the study drugs. Both treatment groups showed improvements from baseline in clinical assessment of lung function carried out after the first 6 weeks of treatment. No significant differences were seen throughout the entire 12 weeks study, when comparing the effects of the treatments on FEV1 FVC, PEF or the histamine PC20 . Asthma severity, symptom score and inhaled bronchodilator use showed the same results after both treatments. It is concluded that inhalations of budesonide and beclomethasone dipropionate in high doses are equally potent in the treatment of severe asthma. There is no significant influence on the adrenal function and no significant side effects during a period equal to that of the present study. 相似文献
The efficacy of budesonide (800 μg b.d.) and beclomethasone dipropionate (750 μg b.d.) in controlling the symptoms of asthma, pulmonary function, bronchial responsiveness to histamine, and adrenal function, was assessed in a double-blind, double-dummy cross-over study of 36 adult chronic asthmatic patients. The patients, the majority of whom were assessed to be affected to a severe degree, were insufficiently controlled in their current regimen of inhaled steroids and/or inhaled and oral bronchodilators. A 2 weeks baseline period preceded 6 weeks of treatment with each of the study drugs. Both treatment groups showed improvements from baseline in clinical assessment of lung function carried out after the first 6 weeks of treatment. No significant differences were seen throughout the entire 12 weeks study, when comparing the effects of the treatments on FEV