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991.
992.
M. Lauritzen R. Dybkær 《Scandinavian journal of clinical and laboratory investigation》2013,73(2):187-190
Owing to its geometry, the observed viscosity obtained with a Wells-Brook-field Micro Viscometer (LVT Cone/Plate, 1.565°) depends on sub-specimen volume. For each apparatus a compromise volume should be found, preferably giving both correct nominal values for Newtonian reference liquids and minimal variation with volume. Besides oil comparison liquids, the use of a water-ethanol comparison liquid is recommended for hemorheological measurements. 相似文献
993.
994.
Neurology manuals generally recommend odor identification for simple assessment of olfaction. Nevertheless, even patients with normal olfaction (normosmics) often perform only poorly. Three experiments demonstrate that such an ambiguous outcome will disappear if the test incorporates highly familiar substances and, more important, a procedure to circumvent the olfactory-verbal gap that frequently separates an odor from its name. One multiple-choice procedure, for instance, led to 100% accuracy among normosmics. Another led to 99% accuracy among normosmics and 0% accuracy among anosmics. The investigation also reveals that scratch-and-sniff labels could possibly replace customary odorants in the clinical test. 相似文献
995.
Mohsen S. Elalfy Ahmad M. Hamdy Sahar S. Abdel Maksoud Reham I. Abdel Megeed 《Nutrition Research》2012
Infants between 6 and 24 months of age are at the highest risk of development of iron deficiency anemia (IDA) in developing countries. Consuming unmodified cow's milk, delayed introduction of solid foods after 6 months, and high birth order could be predictors of the presence of IDA. Three hundred infants between the ages of 6 and 24 months (mean, 13.94 ± 6.17 months) from Ain Shams University Children's Hospital were enrolled in the study. Data collected included demographic information and dietary assessment including the type of milk feeding, introduction of solid foods, and daily iron intake. The infants were examined, and anthropometric measurements were recorded. Anemic infants (hemoglobin level <11 g/dL) were further evaluated by complete blood count, hemoglobin electrophoresis, and iron profile. Anemia was diagnosed among 198 infants (66%), of whom 129 (43%) had IDA. Red cell distribution width at a cutoff value of 15.8% was 86% sensitive and 74% specific in predicting IDA. The main risk factors for IDA included being between 6 and 18 months of age, of the male sex, birth order above the second order, consuming cow's milk, predominant breast-feeding beyond 6 months of age, and low daily iron intake. We conclude that IDA is the most common cause of anemia among Egyptian infants 6 to 24 months old of low socioeconomic standard. Independent clinical predictors were consuming cow's milk during the first 6 months, delayed introduction of solid foods after 6 months, and birth order beyond the second order. 相似文献
996.
Audrey Y.‐C. Kuo Mark Chiew Fred Tam Charles Cunningham Simon J. Graham 《Magnetic resonance in medicine》2011,65(3):715-724
“Real‐time” functional magnetic resonance imaging is starting to be used in neurofeedback applications, enabling individuals to regulate their brain activity for therapeutic purposes. These applications use two‐dimensional multislice echo planar or spiral readouts to image the entire brain volume, often with a much smaller region of interest within the brain monitored for feedback purposes. Given that such brain activity should be sampled rapidly, it is worthwhile considering alternative functional magnetic resonance imaging pulse sequences that trade spatial resolution for temporal resolution. We developed a prototype sequence localizing a column of magnetization by outer volume saturation, from which densely sampled transverse relaxation time decays are obtained at coarse voxel locations using an asymmetric gradient echo train. For 5 × 20 × 20 mm3 voxels, 256 echoes are sampled at ~1 msec and then combined in weighted summation to increase functional magnetic resonance imaging signal contrast. This multiecho coarse voxel pulse sequence is shown experimentally at 1.5 T to provide the same signal contrast to noise ratio as obtained by spiral imaging for a primary motor cortex region of interest, but with potential for enhanced temporal resolution. A neurofeedback experiment also illustrates measurement and calculation of functional magnetic resonance imaging signals within 1 sec, emphasizing the future potential of the approach. Magn Reson Med, 2011. © 2010 Wiley‐Liss, Inc. 相似文献
997.
The three‐dimensional (3D) reconstruction technique serves as a practical tool in diagnosis, surgical planning, and outcome prediction of plastic and reconstructive surgery. In our study, the morphologic features of the Chinese adult orbit were described by 11 anatomic parameters using a 3D reconstruction technique. Sixty‐four Chinese adults were selected randomly from patients who had undergone craniofacial computed tomography (CT) scans to diagnose conditions other than craniofacial or orbital deformations. The morphologic parameters of orbit such as bony orbital volume, orbital foramen area and orbital rim perimeter were measured on 3D models using this technique. Differences between the two orbits and between the two sexes were investigated. The method of measurement showed high reproducibility of results. No difference between the two orbits was found. There were significant differences between men and women in all anatomic parameters other than orbital height. In men and women, respectively, mean bony orbital volume was 26.02 and 23.32 mL, mean orbital foramen area 11.80 and 11.10 cm2, mean orbital rim perimeter 12.65 and 12.20 cm, mean orbital height 33.35 and 33.22 mm, mean orbital width 40.02 and 38.00 mm; mean orbital floor length 47.93 and 46.18 mm, mean orbital roof length 52.93 and 50.89 mm, mean medial orbital wall length 46.43 and 44.41 mm, mean lateral orbital wall length 48.38 and 46.91 mm, mean intraorbital distance 27.18 and 25.11 mm, mean extra‐orbital distance 98.77 and 93.69 mm. It is concluded that the measurements of these orbital parameters could be obtained from a 3D reconstruction method. The two orbits were symmetric based on orbital volume and other anatomic parameters. Orbital size was significantly smaller in women than in men; orbital height, however, was similar. The findings of the present study allow for quantification of the orbital features of Chinese adults and provide parameters for preoperative planning and prediction of postoperative outcome. 相似文献
998.
K. K. Mineev L. N. Prakhova A. G. Il’ves G. V. Kataeva A. M. Petrov T. N. Reznikova A. V. Pozdnyakov I. D. Stolyarov 《Neuroscience and behavioral physiology》2009,39(1):35-38
A total of 65 patients with clinically significant diagnoses of remitting multiple sclerosis in the stage of remission were
studied. Neurological status was investigated with assessment on the FS and EDSS scales, with neuropsychological testing,
and MRI scans (1.5 T). The severity of brain atrophy (in terms of the parenchyma volume) and the total volume of foci on T2
images were assessed as proportions of intracerebral volume. The severity of neurological deficit depended on the volume of
intratentorial focal lesions and the level of brain atrophy. Cognitive disorders were identified in 89% of patients, and the
severity of these was associated with the level of atrophy and the volume of foci on T2 images in the dominant hemisphere.
Translated from Zhurnal Nevrologii i Psikhiatrii imeni S. S. Korsakova, Multiple Sclerosis, Supplement, No. 4, pp. 46–49,
2007. 相似文献
999.
Wolfram Teske Sonja Zirke Jan Nottenk?mper Thomas Lichtinger Theodoros Theodoridis Jürgen Kr?mer Klaus Schmidt 《European spine journal》2011,20(4):537-541
Herniated intervertebral disc causes in a great number of cases of lumbar nerve root compression, especially in the segment
L5/S1. Other reasons responsible for stress to the lumbar spinal root are the spinal canal stenosis and the postdiscotomy
syndrome. For patients without neurological deficiencies, the conservative treatment includes different epidural injection
techniques. Steroids are often applied. A specific injection technique needing only a small drug amount is the epidural perineural
approach using a special two-needle technique. The anatomical spaces of the nerve roots have received little attention in
therapy. We have determined the anterolateral epidural space nerve volume of the nerve root L5/S1, and compared the data collected
in an anatomical study with operative measurements during discectomy. The volume determination in the human cadavers was performed
with liquid silicone filling the anterolateral space after dissection. The in vivo measurements were performed during surgery
at the site of the anterolateral space after discectomy. The anatomical studies showed us a mean value volume of 1.1 ml. The
surgical volume determinations result in a mean volume of 0.9 ml. A better understanding of the anterolateral epidural space
may allow a reduction of the injection volume in the conservative nerve root compression treatment, especially using the epidural
perineural technique, avoiding the risk of side effects of high doses of steroids. 相似文献