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81.
In 1396 consecutively patch tested patients 18 (1.3%) reacted to Kathon CG. Relevance was established in 4 of the 18 patients. The frequency of positive reactions to Kathon CG in eczema patients seems to have been stable in Denmark during the period 1983 to 1988.  相似文献   
82.
大学生预防性治疗的结核菌素反应强度标准研究   总被引:13,自引:3,他引:10  
目的 探讨结核菌素反应强度与结核病发病的相关性;提出预防性治疗对象的结核菌素反应标准.方法 对不同结核菌素反应强度的新入学大学生进行4年的结核病发病观察,分析结核菌素反应强度与发病危险性、发病时间的关系,比较不同反应强度预防性治疗对象发病率的变化.结果 26 543名健康学生进行了结核菌素试验和4年的发病观察,反应强度为0~4、5~9、10~14、15~19和≥20 mm或水泡丘疹者的年均结核病发病率分别为12.97/10万、13.34/10万、50.32/10万、167.56/10万和250.21/10万;0~4和5~9 mm反应者头2年发病率很低,第3、4年有所增高,而15~19和≥20 mm或水泡丘疹者头2年发病率很高,随着时间推移有下降趋势.当逐个计算反应强度每增加1 mm及以上反应者的发病率时,15 mm以上的各反应强度者中结核病发病率相似,一直维持在较高水平.PPD反应标准15 mm及以上可以覆盖80.8%的病人,而且病人的发现效率也维持在一个高水平.结论 结核菌素反应强度与结核病发病存在明显正相关,特别在头2年危险比更大;PPD反应≥15 mm或有水泡丘疹阳性者的发病机会明显升高,PPD反应≥15 mm或有水泡丘疹阳性标准能够覆盖80%以上的病人,病人的发现效率也最高.因此以PPD反应≥15 mm或有水泡丘疹作为预防性治疗对象的结核菌素反应标准更为合理.  相似文献   
83.
A feedforward network is used to recognize short, digitized, isolated utterances. A high, multispeaker recognition rate is achieved with a small vocabulary with a single training utterance. This approach makes use of the pattern recognition property of the network architecture to classify different temporal patterns in the multidimensional feature space. The network recognizes the utterances without the need of segmentation, phoneme identification, or time alignment. We train the network with four words spoken by one single speaker. The network is then able to recognize 20 tokens spoken by 5 other speakers. We repeat the above training and testing procedure using a different speaker's utterances for training each time. The overall accuracy is 97.5%. We compare this approach to the traditional dynamic programming (DP) approach, and find that DP with slope constraints of 0 and 1 achieve 98.5% and 85% accuracies respectively. Finally we validate out statistics by training and testing the network of a four-word subset of the Texas Instruments (Tl) isolated word database. The accuracy with this vocabulary exceeds 96%. By doubling the size of the training set, the accuracy is raised to 98%. Using a suitable threshold, we are able to raise the accuracy of one network from 87% to 98.5%. Thresholding applied to all networks would then raise the overall accuracy to well over 99%.

This technique is especially promising because of the low overhead and computational requirements, which make it suitable for a low cost, portable, command recognition type of application.  相似文献   

84.
The susceptibilities of 40 clinical isolates of Aspergillus spp. (Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, Aspergillus terreus) were determined for posaconazole and voriconazole by the CLSI M38-A and EUCAST-AFST broth dilution methods. Where a discrepancy was observed between the methods, the EUCAST method tended to give higher MIC values. Overall, the level of agreement was 92.5% and the intra-class correlation coefficient was > 0.90.  相似文献   
85.
In a simulation study of inference on population pharmacokinetic parameters, two methods of performing tests of hypotheses comparing two populations using NONMEM were evaluated. These two methods are the test based upon 95% confidence intervals and the likelihood ratio test. Data were simulated according to a monoexponential model and, in that context, power curves for each test were generated for (i)the ratio of mean clearance and (ii)the ratio of the population standard deviations of clearance. To generate the power curves, a range of these parameters was employed; other pharmacokinetic parameters were selected to reflect the variability typically present in a Phase II clinical trial. For tests comparing the means, the confidence interval tests had approximately the same power as the likelihood ratio tests and were consistently more faithful to the nominal level of significance. For comparison of the standard deviations, and when the volume of information available was relatively small, however, the likelihood ratio test was more able to detect differences between the two groups. These results were then compared to results on parameter estimation in order to gain insight into the question of power. As an example, the nonnormality of estimates of the ratio of standard deviations plays an important role in explaining the low power for the confidence interval tests. We conclude that, except for the situation of modeling standard deviations with only sparse information, NONMEM produces tests of significance that are effective at detecting clinically significant differences between two populations.Partial support from the Upjohn Company, NIH-BRSG SO RR 07066, and the Burroughs Wellcome Foundation.  相似文献   
86.
Magnus  Bruze 《Contact dermatitis》1988,19(2):116-119
1310 patients were routinely patch tested with a paratertiary-butylphenol-formaldehyde resin (PTBP-F-R), a resol resin based on phenol and formaldehyde (P-F-R-2), and a mixture of these 2 resins. Approximately 2.5 times more patients with contact allergy to phenol-formaldehyde resins were diagnosed when routinely patch tested with P-F-R-2 in addition to PTBP-F-R. Although patch testing with a mixture of both resins was not as good as patch testing with the 2 resins separately, it was better than testing only with PTBP-F-R, since 1.6 times more patients with contact allergy to phenol-formaldehyde resins were still diagnosed. P-F-R-2 is therefore recommended for routine patch testing, preferably as a separate patch test but otherwise as a mixture with PTBP-F-R.  相似文献   
87.
BACKGROUND: Loss-of-function mutations in the KCNJ2 cause approximately 50% of Andersen-Tawil Syndrome (ATS) characterized by a classic triad of periodic paralysis, ventricular arrhythmia, and dysmorphic features. Do KCNJ2 mutations occur in patients lacking this triad and lacking a family history of ATS? OBJECTIVES: The purpose of this study was to identify and characterize mutations in the KCNJ2-encoded inward rectifier potassium channel Kir2.1 from patients referred for genetic arrhythmia testing. METHODS: Mutational analysis of KCNJ2 was performed for 541 unrelated patients. The mutations were made in wild type (WT) and expressed in COS-1 cells and voltage clamped for ion currents. RESULTS: Three novel missense mutations (R67Q, R85W, and T305A) and one known mutation (T75M) were identified in 4/249 (1.6%) patients genotype-negative for other known arrhythmia genes with overall incidence 4/541 (0.74%). They had prominent U-waves, marked ventricular ectopy, and polymorphic ventricular tachycardia but no facial/skeletal abnormalities. Periodic paralysis was present in only one case. Outward current was decreased to less than 5% of WT for all mutants expressed alone. Co-expression with WT (simulating heterozygosity) caused a marked dominant negative effect for T75M and R82W, no dominant negative effect for R67Q, and a novel selective enhancement of inward rectification for T305A. CONCLUSIONS: KCNJ2 loss of function mutations were found in approximately 1% of patients referred for genetic arrhythmia testing that lacked criteria for ATS. Characterization of three new mutations identified a novel dominant negative effect selectively reducing outward current for T305A. These results extend the range of clinical phenotype and molecular phenotype associated with KCNJ2 mutations.  相似文献   
88.
单宁酸处理带瓣牛颈静脉的生物学评价   总被引:1,自引:0,他引:1  
目的从生物学角度评价单宁酸处理的带瓣牛颈静脉是否符合国家医用材料的要求。方法带瓣牛颈静脉经单宁酸处理后按国家医用材料的要求进行浸提液的制备、细胞毒性试验、过敏试验、皮内刺激试验、原发性皮肤刺激试验、溶血试验、急性全身毒性试验及热原试验等生物学评价试验。试验方法均参照《医用有机硅材料生物学评价试验方法》GB/T16175-1996。结果培养的L-929小鼠成纤维细胞经含浸提液的培养基培养后形态良好,增值旺盛,材料细胞毒性评级为0~1。无皮肤刺激反应和过敏反应,皮内刺激试验PⅡ(原发性刺激指数)为0.4,和阴性对照组差异无统计学意义。全身毒性实验受试动物未出现毒性症状。溶血试验溶血率0.7%,符合国家标准(〈5%)。热原试验经中国药品生物制品检定所检定,单宁酸处理后带瓣牛颈静脉无热原(样品批号:060802017)。结论单宁酸处理的带瓣牛颈静脉符合国家医用材料的要求,可以植入人体。  相似文献   
89.
Rapid, accurate and inexpensive methods are essential to detect drug-resistant Mycobacterium tuberculosis and allow timely application of effective treatment and precautions to prevent transmission. The proportion method, the MTT and Alamar Blue redox methods, and the D29 mycobacteriophage assay, were compared for their ability to detect resistance to isoniazid and rifampicin. When tested against a panel of known M. tuberculosis strains, the redox methods and the D29 assay showed good sensitivity and specificity compared to the proportion method, suggesting that they could be useful alternatives for identifying multidrug resistance in M. tuberculosis.  相似文献   
90.
The differential diagnoses of persistent nonproductive cough include numerous pulmonary and nonpulmonary organic disorders as well as functional illnesses. Many diseases can cause cough, and several studies have shown asthma among the most common etiologies associated with chronic cough in adult nonsmokers, as well as children. Psychogenic cough and its relationship to asthma and other asthma-like illnesses is complex since distinct maladies with similar features may coexist individually or in combination in any given patient. While chronic cough may occur as a sole presenting manifestation of bronchial asthma in all age groups, recent findings suggest that most children with persistent cough without other respiratory symptoms do not have asthma. Since several organic, as well as functional diseases, may present with persistent cough as their sole manifestation in either adults or children, cough should not be used as a single or major determinant to diagnose and treat asthma, especially when empirically focused therapy trials fail. Given the range of illnesses causing cough, no single management guideline can be expected to be universally effective.  相似文献   
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