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71.
Jan G.C. van Amsterdam Stefan Nierkens Sjef G. Vos Antoon Opperhuizen Henkvan Loveren Peter A. Steerenberg 《Archives of environmental & occupational health》2013,68(6):418-423
The sampling of exhaled breath is a noninvasive procedure that can be performed easily in adults, children, and patients with respiratory disease. Several studies have demonstrated increased exhaled nitric oxide in patients with pulmonary disease, including asthma. In addition, exhaled nitric oxide may be an elegant tool for monitoring of environmental health effects of air pollution and the prevalence of atopy in epidemiological surveys. Recent literature about exhaled nitric oxide is presented in this article. Technical, physiological, and behavioral confounding factors of exhaled nitric oxide measurement are outlined. 相似文献
72.
Dwarikanath Mahapatra Peter Schueffler Jeroen A. W. Tielbeek Joachim M. Buhmann Franciscus M. Vos 《Journal of digital imaging》2013,26(5):920-931
Increasing incidence of Crohn’s disease (CD) in the Western world has made its accurate diagnosis an important medical challenge. The current reference standard for diagnosis, colonoscopy, is time-consuming and invasive while magnetic resonance imaging (MRI) has emerged as the preferred noninvasive procedure over colonoscopy. Current MRI approaches assess rate of contrast enhancement and bowel wall thickness, and rely on extensive manual segmentation for accurate analysis. We propose a supervised learning method for the identification and localization of regions in abdominal magnetic resonance images that have been affected by CD. Low-level features like intensity and texture are used with shape asymmetry information to distinguish between diseased and normal regions. Particular emphasis is laid on a novel entropy-based shape asymmetry method and higher-order statistics like skewness and kurtosis. Multi-scale feature extraction renders the method robust. Experiments on real patient data show that our features achieve a high level of accuracy and perform better than two competing methods. 相似文献
73.
74.
75.
Verya Daeichin Deep Bera Shreyas Raghunathan Maysam Shabani Motlagh Zhao Chen Chao Chen Emile Noothout Hendrik J. Vos Michiel Pertijs Johan G. Bosch Nico de Jong Martin Verweij 《Ultrasound in medicine & biology》2018,44(10):2143-2154
This paper presents the design, fabrication and characterization of a miniature PZT-on-CMOS matrix transducer for real-time pediatric 3-dimensional (3D) transesophageal echocardiography (TEE). This 3D TEE probe consists of a 32?×?32 array of PZT elements integrated on top of an Application Specific Integrated Circuit (ASIC). We propose a partitioned transmit/receive array architecture wherein the 8?×?8 transmitter elements, located at the centre of the array, are directly wired out and the remaining receive elements are grouped into 96 sub-arrays of 3?×?3 elements. The echoes received by these sub-groups are locally processed by micro-beamformer circuits in the ASIC that allow pre-steering up to ±37°. The PZT-on-CMOS matrix transducer has been characterized acoustically and has a centre frequency of 5.8 MHz, -6 dB bandwidth of 67%, a transmit efficiency of 6 kPa/V at 30 mm, and a receive dynamic range of 85 dB with minimum and maximum detectable pressures of 5 Pa and 84 kPa respectively. The properties are very suitable for a miniature pediatric real-time 3D TEE probe. 相似文献
76.
77.
C. H. J. Verhoeven T. T. M. van Munster G. M. M. Groothuis R. M. E. Vos I. M. C. M. Rietjens 《Xenobiotica; the fate of foreign compounds in biological systems》2013,43(2):109-118
1. The type of human P450 enzymes involved in the in vitro metabolism of Org 4060 and Org 30659, two synthetic steroidal hormones currently under clinical development by NV Organon for use in oral contraceptive and hormone replacement therapy, was investigated. 2. Both steroids were mainly hydroxylated at the 6 β -position in incubations with human liver microsomes. 3. The results from experiments with supersomes, correlation studies as well as inhibition studies with ketoconazole, a selective inhibitor of CYP3A, strongly suggest that the CYP3A family plays a significant role in the 6 β -hydroxylation of both steroids. 4. Measurements of kinetic parameters of P450 enzymes that could metabolize both steroids, combined with the fact that CYP3A4 is known to be the most abundant P450 enzyme in the human liver, indicate that CYP3A4 will be of major importance for the in vivo human metabolism of Org 4060 and Org 30659. 相似文献
78.
Background
The huge importance of rapid provision of care, especially early defibrillation, for survival of out-of-hospital cardiac arrest (OHCA) is well known. This prospective cohort study investigated cognitive functioning of OHCA survivors in relation to the time-related elements of the resuscitation.Methods
Fifty-seven consecutive survivors, from a cohort of 308 witnessed OHCA patients with ventricular fibrillation as the initial rhythm, underwent extensive neuropsychologic examination, including tests of memory, attention, and executive functioning, 6 months after the resuscitation. Time-related aspects of the resuscitation were collected on scene. Cognitive functioning was studied in relation to the administration of cardiopulmonary resuscitation (CPR) prior to ambulance arrival, and time from collapse to start of CPR, defibrillation, and return of spontaneous circulation (ROSC).Results
Depending of the test, between 11% and 28% of survivors were cognitively impaired, while 58% scored unimpaired for all tests. Daily life activities were limited in 19% of the patients. Patients who received CPR prior to arrival of the ambulance showed a trend towards overall better cognitive functioning and significant better immediate memory and visuomotor tracking (P = .03 and P < .01). We found a weak correlation between the time to CPR, time to defibrillation, or time to ROSC and cognitive functioning.Conclusions
The majority of survivors of OHCA with ventricular fibrillation as the initial rhythm are cognitively unimpaired. Long delays to ROSC are compatible with good cognitive outcome. Initiation and cessation of resuscitation efforts should not be based on the duration of circulatory arrest. 相似文献79.
80.
Budesonide in collagenous colitis: a double-blind placebo-controlled trial with histologic follow-up. 总被引:7,自引:0,他引:7
Filip Baert Alain Schmit Geert D'Haens Franceska Dedeurwaerdere Edouard Louis Marc Cabooter Martine De Vos Fernand Fontaine Serge Naegels Piet Schurmans Hedwig Stals Karel Geboes Paul Rutgeerts 《Gastroenterology》2002,122(1):20-25
BACKGROUND & AIMS: Collagenous colitis (CC) is a well-described entity causing chronic diarrhea and characteristic histologic findings. Several treatment options have been suggested, but no controlled data are available. We conducted a placebo-controlled trial to show the clinical and histologic effects of budesonide in CC. METHODS: Twenty-eight patients were randomly assigned to receive placebo (n = 14) or budesonide 9 mg daily (n = 14) for 8 weeks. Patients were evaluated clinically, and blinded biopsy specimens were analyzed from fixed locations at weeks 0 and 8. Clinical response was defined as a decrease of at least 50% in the disease activity score (number of bowel movements in the last 7 days). At week 8, nonresponders received open-label budesonide for the next 8-week period; responders discontinued treatment and were followed up. RESULTS: Three patients discontinued the study prematurely. Intention-to-treat analysis showed clinical response in 8 of 14 patients in the budesonide group compared with 3 of 14 responders for placebo (P = 0.05) after 8 weeks of blinded therapy, together with improved stool consistency. Histologically, there was no change in the mean thickness of the collagen band but a significant decrease of the lamina propria infiltrate in the budesonide group (P < 0.001). CONCLUSIONS: Budesonide is efficacious in inducing short-term clinical response in CC with significant reduction of the histologic infiltrate in the lamina propria. 相似文献