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101.
Maarten W. Kroes Wendy M.H. Busser Jurgen J. Fütterer Mark J. Arntz Caroline M.M. Janssen Yvonne L. Hoogeveen Frank de Lange Leo J. Schultze Kool 《Journal of vascular and interventional radiology : JVIR》2013,24(6):901-906
PurposeTo assess whether the use of needle guidance devices can reduce fluoroscopy time and operator hand dose during cone-beam computed tomography–guided needle interventions.Materials and MethodsThe freehand technique was compared with techniques employing two distinct needle holders and a ceiling-mounted laser guidance technique. Laser guidance was used either alone or in combination with needle holders. Four interventional radiologists were instructed to reach predetermined targets in an abdominal phantom using these techniques. Each operator used all six techniques three times. Fluoroscopy time, procedure time, operator hand dose, and needle tip deviation were obtained for all simulated needle interventions. All data are presented as median (ranges).ResultsAll procedures were successfully completed within 2–4 minutes, resulting in a deviation from target of 0.8 mm (0–4.7). In freehand procedures, the fluoroscopy time to reach the target was 50 seconds (31–98 s). Laser guidance, used alone or in combination with needle holders, reduced fluoroscopy time to 31 seconds (14–68 s) (P<.02). The operator hand dose in freehand procedures was 275 μSv (20–603 μSv). Laser guidance alone or in combination with needle holders resulted in a reduction of the hand dose to<36 μSv (5–82 μSv) per procedure (P<.001). There were no statistically significant effects on hand dose levels or fluoroscopy time when the needle holders were employed alone.ConclusionsCompared with the freehand technique, all three tested needle guidance devices performed with equivalent efficiency in terms of accuracy and procedure time. Only the addition of laser guidance was found to reduce both fluoroscopy time and operator hand dose. 相似文献
102.
Arck PC Rücke M Rose M Szekeres-Bartho J Douglas AJ Pritsch M Blois SM Pincus MK Bärenstrauch N Dudenhausen JW Nakamura K Sheps S Klapp BF 《Reproductive biomedicine online》2008,17(1):101-113
Many pregnancies are lost during early gestation, but clinicians still lack tools to recognize risk factors for miscarriage. Thus, the identification of risk factors for miscarriage during the first trimester in women with no obvious risk for a pregnancy loss was the aim of this prospective cohort trial. A total of 1098 women between gestation weeks 4 and 12 in whom no apparent signs of a threatened pregnancy could be diagnosed were recruited. Demographic, anamnestic, psychometric and biological data were documented at recruitment and pregnancy outcomes were registered subsequently. Among the cases with sufficiently available data, 809 successfully progressing pregnancies and 55 subsequent miscarriages were reported. In this cohort, risk of miscarriage was significantly increased in women at higher age (>33 years), lower body mass index (< or =20 kg/ m(2)) and lower serum progesterone concentrations (< or =12 ng/ml) prior to the onset of the miscarriage. Women with subsequent miscarriage also perceived higher levels of stress/demands (supported by higher concentrations of corticotrophin-releasing hormone) and revealed reduced concentrations of progesterone-induced blocking factor. These risk factors were even more pronounced in the subcohort of women (n = 335) recruited between gestation weeks 4 and 7. The identification of these risk factors and development of an interaction model of these factors, as introduced in this article, will help clinicians to recognize pregnant women who require extra monitoring and who might benefit from therapeutic interventions such as progestogen supplementation, especially during the first weeks of pregnancy, to prevent a miscarriage. 相似文献
103.
Adrian M. Dubuc Marc Remke Andrey Korshunov Paul A. Northcott Shing H. Zhan Maria Mendez-Lago Marcel Kool David T. W. Jones Alexander Unterberger A. Sorana Morrissy David Shih John Peacock Vijay Ramaswamy Adi Rolider Xin Wang Hendrik Witt Thomas Hielscher Cynthia Hawkins Rajeev Vibhakar Sidney Croul James T. Rutka William A. Weiss Steven J. M. Jones Charles G. Eberhart Marco A. Marra Stefan M. Pfister Michael D. Taylor 《Acta neuropathologica》2013,125(3):373-384
104.
105.
Padmavathi Sundaram William M. Wells Robert V. Mulkern Ellen J. Bubrick Edward B. Bromfield Mirjam Münch Darren B. Orbach 《Magnetic resonance in medicine》2010,64(6):1728-1738
Neuronal currents produce local electromagnetic fields that can potentially modulate the phase of the magnetic resonance signal and thus provide a contrast mechanism tightly linked to neuronal activity. Previous work has demonstrated the feasibility of direct MRI of neuronal activity in phantoms and cell culture, but in vivo efforts have yielded inconclusive, conflicting results. The likelihood of detecting and validating such signals can be increased with (i) fast gradient‐echo echo‐planar imaging, with acquisition rates sufficient to resolve neuronal activity, (ii) subjects with epilepsy, who frequently experience stereotypical electromagnetic discharges between seizures, expressed as brief, localized, high‐amplitude spikes (interictal discharges), and (iii) concurrent electroencephalography. This work demonstrates that both MR magnitude and phase show large‐amplitude changes concurrent with electroencephalography spikes. We found a temporal derivative relationship between MR phase and scalp electroencephalography, suggesting that the MR phase changes may be tightly linked to local cerebral activity. We refer to this manner of MR acquisition, designed explicitly to track the electroencephalography, as encephalographic MRI (eMRI). Potential extension of this technique into a general purpose functional neuroimaging tool requires further study of the MR signal changes accompanying lower amplitude neuronal activity than those discussed here. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
106.
This study aimed to investigate the role of sleep physiology in recovery from burnout, in particular the relation between sleep and changes in fatigue and whether those changes would be related to return to work.23 white-collar workers on long-term sick leave (>3 months) due to a burnout related diagnosis and 16 healthy controls were subjected to polysomnographic recordings at baseline and after 6-12 months’ rehabilitation. Occupational status, subjective sleep quality, fatigue, anxiety and depression were assessed. Recovery from burnout was accompanied by improved sleep continuity. Significant interaction effects were seen for number of arousals, sleep fragmentation, sleep latency, sleep efficiency and time of rising. The burnout group improved significantly on all symptom variables although the post-treatment levels did not reach the levels of the controls. Recovery from fatigue was related to a reduction of the arousal from sleep and was the best predictor of return to work. 相似文献
107.
In patients with community-acquired pneumonia, traditional criteria of infection based on clinical signs and symptoms, clinical
scoring systems, and general inflammatory indicators (for example, leukocytosis, fever, C-reactive protein and blood cultures)
are often of limited clinical value and remain an unreliable guide to etiology, optimal therapy and prognosis. Procalcitonin
is superior to other commonly used markers in its specificity for bacterial infection (allowing alternative diagnoses to be
excluded), as an indicator of disease severity and risk of death, and mainly as a guide to the necessity for antibiotic therapy.
It can therefore be viewed as a diagnostic, prognostic, and perhaps even theragnostic test. It more closely matches the criteria
for usefulness than other candidate biomarkers such as C-reactive protein, which is rather a nonspecific marker of acute phase
inflammation, and proinflammatory cytokines such as plasma IL-6 levels that are highly variable, cumbersome to measure, and
lack specificity for systemic infection. Elevated levels of pro-adrenomedullin, copeptin (which is produced in equimolar amounts
to vasopressin), natriuretic peptides and cortisol are significantly related to mortality in community-acquired pneumonia,
as are other prohormones such as pro-atrial natriuretic peptide, coagulation markers, and other combinations of inflammatory
cytokine profiles. However, all biomarkers have weaknesses as well as strengths. None should be used on its own; and none
is anything more than an aid in the exercise of clinical judgment based upon a synthesis of available clinical, physiologic
and laboratory features in each patient. 相似文献
108.
R. van Vugt J. Deunk M. Brink H. M. Dekker D. R. Kool A. B. van Vugt M. J. Edwards 《European journal of trauma and emergency surgery》2011,37(2):185-190
Introduction
Many scoring systems have been proposed to predict the survival of trauma patients. This study was performed to evaluate the influence of routine thoracoabdominal computed tomography (CT) on the predicted survival according to the trauma injury severity score (TRISS). 相似文献109.
E.J. Mirjam Blokker Bianca M. van de Ven Cindy M. de Jongh P.G.G. Slaats 《Environmental health perspectives》2013,121(5):600-606
Background: Coal tar and bitumen have been historically used to coat the insides of cast iron drinking water mains. Polycyclic aromatic hydrocarbons (PAHs) may leach from these coatings into the drinking water and form a potential health risk for humans.Objective: We estimated the potential human cancer risk from PAHs in coated cast iron water mains.Method: In a Dutch nationwide study, we collected drinking water samples at 120 locations over a period of 17 days under various operational conditions, such as undisturbed operation, during flushing of pipes, and after a mains repair, and analyzed these samples for PAHs. We then estimated the health risk associated with an exposure scenario over a lifetime.Results: During flushing, PAH levels frequently exceeded drinking water quality standards; after flushing, these levels dropped rapidly. After the repair of cast iron water mains, PAH levels exceeded the drinking water standards for up to 40 days in some locations.Conclusions: The estimated margin of exposure for PAH exposure through drinking water was > 10,000 for all 120 measurement locations, which suggests that PAH exposure through drinking water is of low concern for consumer health. However, factors that differ among water systems, such as the use of chlorination for disinfection, may influence PAH levels in other locations. 相似文献
110.