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131.
The purpose of this study was to assess the time of onset of action of acrivastine in suppressing the wheal response to histamine (10 mg/ml) and allergen (10000 and 100000 BU/ml) in the skin prick test. Ten subjects with a well-documented allergy to pollen received single doses of 8 mg of acrivastine and placebo according to a randomized, double-blind, placebo-controlled, crossover treatment design. Duplicate skin prick tests were performed 0, 15, 20, 25, 30, and 60 min after medication. The results demonstrated a statistically significant suppression of the wheal reactions 15–20 min after medication, depending on the reaction producers used. The sum of all three producers showed a statistically significant effect on the wheal reaction 15 min after medication. The upper 95% confidence limit for time lag from dosing of acrivastine until reduction from placebo level commences was 6.5 min. The study substantiates that orally administered acrivastine has a rapid onset of action in the skin of allergic subjects. The results indicate that allergen SPT is a more sensitive tool for studying antihistaminergic activity than histamine SPT. 相似文献
132.
Establishment of predictive variables associated with testicular sperm retrieval in men with non-obstructive azoospermia 总被引:2,自引:0,他引:2
Although testicular biopsy for sperm extraction is a procedure with a potential for complications, sperm retrieval is successful in 30-70% of patients with non-obstructive azoospermia. In order to predict the probability of retrieving at least one testicular spermatozoon we conducted a prospective study of a set of variables in 40 patients with non-obstructive azoospermia. Using the receiver operating characteristic curves, we determined the probability estimates of testicular volume, plasma follicle stimulating hormone (FSH) concentration, Johnsen score and visualization of testicular spermatids in discriminating between patients with successful and failed testicular sperm extraction. Visualization of testicular spermatids provided the best estimate of success of testicular sperm extraction. Of the factors studied using logistic-regression analysis (age, maternal and paternal age at birth, body mass index, luteinizing hormone, testosterone, FSH, testicular volume, the presence of testicular spermatids and Johnsen score), only the presence of spermatids and Johnsen score were independent variables able to predict the success of testicular sperm extraction. The visualization of the presence of spermatids gave a correct prediction of 77% and Johnsen score of 71%. The diagnostic model derived from these independent predictors when validated in 40 patients using the Jackknife technique gave a correct overall prediction of 87%. The probability of successful testicular sperm extraction in patients with non-obstructive azoospermia could be objectively predicted on the basis of simple histopathological criteria represented by the visualization of testicular spermatids and Johnsen score. 相似文献
133.
Lilleri D Baldanti F Gatti M Rovida F Dossena L De Grazia S Torsellini M Gerna G 《Journal of medical virology》2004,73(3):412-418
Transplantation Centers using human cytomegalovirus (HCMV) antigenemia-based preemptive therapy will need to replace in the near future the antigenemia assay with a more standardized and automatable assay, such as a molecular assay quantifying HCMV DNA in blood (DNAemia). Thus, in view of replacing antigenemia with clinically safe cutoff values, DNAemia levels corresponding to antigenemia cutoffs guiding HCMV preemptive therapy were determined retrospectively in solid organ and hematopoietic stem cell transplant recipients (HSCTR) using an "in-house" quantitative PCR (QPCR) method. Since preemptive therapy had prevented appearance of HCMV disease in all patients tested, DNA cutoffs determined retrospectively had to be considered as safe clinically as antigenemia cutoffs used prospectively. However, in solid organ transplant recipients (SOTR), initiating preemptive therapy upon an antigenemia cutoff of 100 pp65-positive leukocytes, a DNAemia cutoff of 300,000 copies/ml blood had positive and negative predictive values of >90%, indicating that a DNAemia cutoff could achieve, in terms of prevention of HCMV disease, the same clinical results as the antigenemia cutoff. In HSCTR, initiating preemptive therapy upon first antigenemia positivity, a DNAemia cutoff of 10,000 copies/ml blood had a positive predictive value of >90%, indicating that the great majority of patients treated under the antigenemia guidance would have been treated also using this DNA cutoff. On the other hand, the negative predictive value of 28.6% indicated that two out of three HSCTR had been treated under the antigenemia guidance having the same levels of viral DNA as the untreated patients. The data suggest that a quantitative cutoff could be adopted as a guiding criterion for preemptive therapy also in HSCTR. Regression analysis allowed to determine the DNAemia (corresponding to QPCR) cutoff values for two commercial assays tested both in solid organ and HSCTR. Retrospective DNAemia cutoff values will be verified for safety in prospective trials. 相似文献
134.
Frank H. Duffy Kenneth Jones Peter Bartels Gloria McAnulty Marilyn Albert 《Brain topography》1992,4(4):291-307
Summary Principal components analysis (PCA) was performed on the 1536 spectral and 2944 evoked potential (EP) variables generated by neurophysiologic paradigms including flash VER, click AER, and eyes open and closed spectral EEG from 202 healthy subjects aged 30 to 80. In each case data dimensionality of 1500 to 3000 was substantially reduced using PCA by magnitudes of 20 to over 200. Just 20 PCA factors accounted for 70% to 85% of the variance. Visual inspection of the topographic distribution of factor loading scores revealed complex loadings across multiple data dimensions (time-space and frequency-space). Forty-two non-artifactual factors were successful in classifying age, gender, and a separate group of 60 demented patients by linear discriminant analysis. Discrimination of age and gender primarily involved EP derived factors, whereas dementia primarily involved EEG derived factors. Thirty-eight artifactual factors were identified which, alone, could not discriminate age but were relatively successful in discriminating gender and dementia. The need to parsimoniously develop real neurophysiologic measures and to objectively exclude artifact are discussed. Unrestricted PCA is suggested as a step in this direction.Acknowledgements: This work was supported in part by NIA program project PO1AG049853 to M. Albert and the Mental Retardation Program Project P30HD18655 to J.J. Volpe. We thank our qEEG technologists Adele Mirabella, Susan Katz, Ellen Belles, and Marianne McGaffigan as well as our research secretaries for their unflagging support. 相似文献
135.
Mengoli C Cusinato R Biasolo MA Cesaro S Parolin C Palù G 《Journal of medical virology》2004,74(1):78-84
After bone marrow (BM) or solid-organ (SO) transplantation viremic Cytomegalovirus (CMV) infection is observed frequently. Quantitative assay of CMV in blood helps the management of this clinical condition. In the present report, 83 samples from 39 solid organ recipients, three CMV assays were compared simultaneously for the first time: the Nuclisens CMV pp67 assay (nucleic acid sequence-based amplification, NASBA), an "in-house" quantitative real-time PCR assay (TaqMan) for CMV DNA, and pp65 antigenemia. The relation between CMV DNA and pp65 antigenemia, the quantitative assays, was evaluated on a larger group including 251 blood samples from 118 solid organ recipients. Real-time PCR provided the best results; > or =130 CMV DNA copies/2 x 10(5) peripheral blood leukocytes (PBLs) predicted > or =1 pp65 antigen positive (Ag+) cell/2 x 10(5) PBLs. By taking pp65 antigenemia as the "gold standard," the sensitivity of CMV DNA quantitation and of the pp67 RNA assay were 0.95 and 0.20, respectively, while the corresponding specificity values were 0.50 and 0.93. When real-time PCR was considered as the "gold standard," the sensitivity and specificity of the pp65 antigenemia were 0.65 and 0.91, respectively. Among the three tests examined, the sensitivity of the pp67 RNA assay was the lowest. On the other hand, the pp67 RNA assay was highly specific and effective in pinpointing high viremia patients. The present report, by providing predictive values for all three diagnostic profiles, DNA load, antigenemia, and pp67RNA, is a contribution for validation of real-time PCR as a new standard for quantitative assessment of CMV viremia in clinical settings. 相似文献
136.
Martin Griebe Michael Daffertshofer Mark Stroick Magdalena Syren Parviz Ahmad-Nejad Michael Neumaier Juergen Backhaus Michael G. Hennerici Marc Fatar 《Neuroscience letters》2007
Biological markers play an evolving role in the diagnosis of Alzheimer disease (AD). We compare conventional measurements of cerebrospinal fluid (CSF) tau and β-amyloid1–42 proteins to a novel approach – Fourier transformed infrared (FT-IR) spectroscopy – a simple technique derived from chemical and physical sciences that characterizes intramolecular bonds. For automatic diagnostic analysis, we developed an artificial neural network (ANN). We examined 71 patients with a clinical diagnosis of AD and 66 controls. β-Amyloid1–42 was decreased (sensitivity 80% and specificity 78%); tau was elevated (sensitivity 76% and specificity 88%) in CSF of AD patients. The combined tau/β-amyloid1–42 quotient was able to distinguish healthy from diseased subjects with 99% sensitivity and 86% specificity. The ANN could separate FT-IR spectroscopy data with 88.5% sensitivity and 80% specificity. FT-IR spectroscopy proved to be cost-effective and simple to perform. Diagnostic sensitivity and specificity is in the range of CSF tau and β-amyloid1–42 protein analysis. Larger sample numbers for ANN training and validation could increase diagnostic accuracy and thus prove to be a useful screening tool. 相似文献
137.
THOMAS PENZEL 《Journal of sleep research》1995,4(S1):15-20
SUMMARY Arterial blood pressure is influenced by sleep-related breathing disorders. As cardiovascular consequences can be diagnosed by an accurate recording and analysis of blood pressure, new recording methodologies and an approach to analysis are presented here. Invasive continuous blood pressure recording is the common reference for all methodologies. As blood pressure varies rapidly in parallel with sleep-related breathing disorders it is indispensible to record blood pressure continuously. To introduce non-invasive methodology the Finapres system was used during sleep studies; a validation study showed severe limitations. This study was followed by the validation of an improved system called Portapres, which is portable, has two finger cuffs and a hydrostatic height compensation.
Analysis of continuous blood pressure in patients with sleep apnoea is carried out to detect mechanisms which influence the cardiovascular risk. Spectrum analysis of systolic blood pressure showed two different major oscillations present in patients with obstructive sleep apnoea. One oscillation (<0.06 Hz) occurs in parallel with each apnoeic episode and the other oscillation (0.2-0.4 Hz) occurs in parallel with the obstructive efforts during each apnoea and in parallel with respiration during periods of snoring. These two oscillations were so specific that the use of non-invasive continuous blood pressure recording allowed an estimation of the extent of underlying breathing disorders, and assessment of cardiovascular risk in a patient with obstructive apnoea in terms of hypertension and on the basis of ambulatory monitoring. 相似文献
Analysis of continuous blood pressure in patients with sleep apnoea is carried out to detect mechanisms which influence the cardiovascular risk. Spectrum analysis of systolic blood pressure showed two different major oscillations present in patients with obstructive sleep apnoea. One oscillation (<0.06 Hz) occurs in parallel with each apnoeic episode and the other oscillation (0.2-0.4 Hz) occurs in parallel with the obstructive efforts during each apnoea and in parallel with respiration during periods of snoring. These two oscillations were so specific that the use of non-invasive continuous blood pressure recording allowed an estimation of the extent of underlying breathing disorders, and assessment of cardiovascular risk in a patient with obstructive apnoea in terms of hypertension and on the basis of ambulatory monitoring. 相似文献
138.
作者自行设计的CSS-Ⅱ型心电图微型计算机自动诊断系统试用于临床,受试者1160例,其中波形异常和心律失常共247份心电图,从913份正常心电图中随机抽样106份,两者共计353份图纸,用本研究诊断确定的“金标准”(Gold standard)与该系统的自动诊断结论进行比较。结果:波形诊断及心律失常的诊断一致率均在90%以上,排除了机遇诊断一致率,其波形为90%,心律失常为88%。 相似文献
139.
作者用“点值法”对成都市内和郊区842例从事轻、中、重劳动的健康工人、农民和战士作了MEFV曲线和常规肺功能测定,发现工人和农民在低肺容积时流量增加,在高、中肺容积时流量下降,并以农民最明显,重劳动工人次之,轻、中劳动工人较不明显,战士则相反。揭示不同的体力活动方式及生活条件可导致不同肺容积时的流量改变,以适应其代谢增强时的耗氧需求。 相似文献
140.
娄志辉 《中国医疗器械信息》2022,(4)
目的:分析在鼻部整形中三维及多平面重建CT技术的应用价值。方法:选择2018年2月~2019年7月本院收治的60例行鼻部整形的患者进行分析,所有患者均开展三维及多平面重建CT技术检测,结合检查结果,开展相应的隆鼻手术。分析术后不良反应、患者满意度。术后6个月,在CT测量下,检测前后鼻部解剖数据。结果:在鼻部整形中,三维及多平面重建CT技术的应用,可以准确了解鼻部结构,如观察侧鼻骨、鼻部皮肤、鼻根等情况。术后评价,患者对鼻部整形满意度较高,术后6个月,患者对鼻部整形满意度较高,术后与术后6个月患者鼻部满意度相比,无统计学意义,P>0.05。术后60例患者没有出现出血、切口感染等反应,同时也没有出现肋软骨外漏与倾斜等现象。经随访术后6个月发现1例患者的鼻背软骨出现轻度弯曲,但无明显表现,没有做特殊处理;其余患者,鼻部外形均表现为鼻尖挺拔、鼻背曲线流畅。结论:在鼻部整形中,应用三维及多平面重建CT技术,可以辅助提高隆鼻手术准确度,并在CT技术的引导下,准确植入自体肋软骨,可以为手术成功奠定基础,促使鼻唇与周围器官形态的协调性,进一步提高患者满意度。 相似文献