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31.
Corinna S. Bowser Jean Kaye Rauno O. Joks Cascy-Arnoux Charlot H. Jack Moallem 《Pediatric allergy and immunology》2007,18(4):298-303
Elevated serum immunoglobulin E (IgE) and increased prevalence of atopy is reported in patients infected with human immunodeficiency virus (HIV). The elevated serum IgE may be attributed to polyclonal stimulation of B cells or IgE production against allergens, viruses, fungi and bacteria. This study investigates the prevalence of atopy in perinatally HIV-infected children, and the relationships between serum IgE (and other serum immunoglobulins) with atopy, CD4+ cell count and HIV-disease stage. Serum immunoglobulin levels, epicutaneous skin test for common aeroallergens, clinical Centers for Disease Control and Prevention (CDC) classification, CD4+ cell counts and allergy history were extracted from the charts of perinatally HIV-infected children on highly active antiretroviral therapy. The prevalence of atopy (52%) and the pattern of aeroallergen sensitivity were comparable with the US pediatric population. Serum IgE levels did not correlate with clinical disease stage. However, in non-atopic patients, serum IgE levels increased with disease progression (p = 0.02). There was an inverse relationship between the prevalence of elevated serum IgE levels and atopy with progression of disease (p = 0.019). Serum IgE did not correlate with atopy, CD4+ cell count, or duration of HIV infection or levels of serum immunoglobulins. This is the first study to show no increased prevalence of atopy in perinatally HIV-infected children compared with the general population. In advanced stages of HIV, elevated serum IgE may be specific for antigens other than those known as allergens. 相似文献
32.
A total of 240 survivors of one or more myocardial infarctions were consecutively admitted to perform supine exercise radionuclide ventriculography. Within 3 years after the test, 22 died; this group was compared to an age-matched control group of 22 survivors for left and right ventricular function during rest, exercise, and simultaneously assessed exercise performance as well as ECG variables. Evaluation of 3-year survival by linear discriminant analysis revealed an accuracy of 82% for discriminant models using ECG and exercise performance variables. Implementation of resting left ventricular ejection fraction and change of right ventricular ejection fraction during exercise, as well as scintigraphic presence or absence of dyskinesia, improved the accuracy of the model to 91% of correctly classified patients. 相似文献
33.
V. van Casteren P. Leurquin A. Bartelds F. Gurtner V. Massari S. Maurice-Tison A.T. Vega R. Mak 《European journal of epidemiology》1993,9(2):169-175
This study describes a p. year international data collection on the demand pattern for HIV-antibody tests in general practice recorded by 6 sentinel networks in 5 European countries. The purpose of the recording was to evaluate the use of HIV-antibody testing by general practitioners and the demand for testing among the general population. Sentinel networks of general practitioners are a possible and available instrument for monitoring the perception of the HIV-test, and indirectly of the threat of the HIV-epidemic by the public and by the general practitioners (GPs). Differences were found between the countries in the frequency of testing, the person asking the test and the reason for testing. Possible explanatory factors, such as differences in the routine testing of specific groups, differences in the training and in the role of the GP, differences in the characteristics of prevention policy, are discussed. The European comparison also offers the opportunity to reflect on common medical practice in dealing with demands for HIV-tests. 相似文献
34.
Bipolar affective disorder. II. EEG, neuropsychological, and clinical correlates of CT abnormality 总被引:1,自引:0,他引:1
M J Dewan C V Haldipur M F Boucher T Ramachandran L F Major 《Acta psychiatrica Scandinavica》1988,77(6):677-682
Since the clinical significance of CT abnormalities found in bipolar patients remains obscure, we studied 26 DSM-III bipolar patients who had specific CT abnormalities (third ventricle enlargement, and hyperdensity of the caudate, thalamus, anterior frontal white matter, and right temporal lobe) on numerous parameters such as EEG, the Halstead-Reitan Neuropsychological Battery, premorbid personality adjustment, family history of affective disorder, positive and negative symptoms, employment history, and response to lithium carbonate treatment. None of these measures could differentiate between the CT abnormal and CT normal subgroups. The implications of these findings are discussed. 相似文献
35.
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
36.
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
37.
Donald B. White Cynthia A. Walawander Dong Y. Liu Thaddeus H. Grasela 《Journal of pharmacokinetics and pharmacodynamics》1992,20(3):295-313
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
38.
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
39.
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
40.
Anthony J Linz 《The Journal of asthma》2007,44(5):347-355
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