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Postural and eye-blink reactions to acoustic startle probes were examined in 24 volunteers, who completed two blocked conditions (baseline, startle). A postural reaction during the startle condition demonstrated a reflexive movement in the anterior-posterior direction, which was not observed during the baseline condition. This reflexive response was positively associated with the eye-blink reflex, such that larger blink magnitude related to greater posterior movement. These findings were not observed for postural movements in the medial-lateral direction. The results suggest that a measurable postural reaction may be observed following a startling acoustic stimulus, which may reflect generalized bodily flexion associated with a preparatory behavioral response.  相似文献   
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This paper presents a syntactic/semantic string representation scheme as well as a string matching method as part of a computer-assisted system to identify dolphins from photographs of their dorsal fins. A low-level string representation is constructed from the curvature function of a dolphin's fin trailing edge, consisting of positive and negative curvature primitives. A high-level string representation is then built over the low-level string via merging appropriate groupings of primitives in order to have a less sensitive representation to curvature fluctuations or noise. A family of syntactic/semantic distance measures between two strings is introduced. A composite distance measure is then defined and used as a dissimilarity measure for database search, highlighting both the syntax (structure or sequence) and semantic (attribute or feature) differences. The syntax consists of an ordered sequence of significant protrusions and intrusions on the edge, while the semantics consist of seven attributes extracted from the edge and its curvature function. The matching results are reported for a database of 624 images corresponding to 164 individual dolphins. The identification results indicate that the developed string matching method performs better than the previous matching methods including dorsal ratio, curvature, and curve matching. The developed computer-assisted system can help marine mammalogists in their identification of dolphins, since it allows them to examine only a handful of candidate images instead of the currently used manual searching of the entire database. © 2000 Biomedical Engineering Society. PAC00: 8780Tq, 4230Sy, 0705Pj  相似文献   
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Marrow radioiron kinetics   总被引:2,自引:0,他引:2  
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Five patients with coexistent carcinoma of the lung and active tuberculosis within the same pulmonary lesion were studied. These cases represent five distinctly varying radiographic presentations and point out the extreme diversity of the morphological pictures of this particular disease combination. Physicians who regularly deal with patients who might present with either entity alone are cautioned to be alert to the possibility that these two diseases may be present simultaneously within single, specific pulmonary lesions.  相似文献   
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The sweat patch is a new, noninvasive method designed to estimate the ethanol consumption of drinking subjects. It consists of salt-impregnated absorbent pads protected by a plastic chamber with attached water-tight adhesive. The patch reportedly collects transepidermal fluid at a steady rate for up to 10 days. Recent laboratory research has indicated a linear relationship between the concentration of ethanol in transepidermal fluid and mean concentration of ethanol in blood. Levels of ethanol in the sweat patch allowed identification of persons drinking at least 0.5 g of ethanol/kg/day with 100% sensitivity and specificity. The study reported here was conducted to test the field effectiveness of this sweat patch in normal, active research subjects. First, several pretests were conducted to determine the optimal location of the patch on the body and its fluid uptake at various sites. A laboratory experiment using nonalcoholic subjects was conducted to replicate previous work, and methods of measuring ethanol concentration in the patch were refined. A field test of the patch was then carried out. Healthy active volunteers drank a single "moderate" dose of ethanol (0.5 g of ETOH/kg of body weight) and then remained abstinent for the next 3 days. A week later, a "heavy" dose (1.0/kg of body weight) was consumed. Only a trace of ethanol was detected in any of the patches worn in either experiment. The patch did not measure ethanol in the transepidermal fluid under field conditions. Thus, further design modifications and pilot testing are required before the full benefits of this unobtrusive measure of drinking can be realized.  相似文献   
19.
Videofluoroscopic analysis of the infant swallow   总被引:1,自引:0,他引:1  
A better understanding of the abnormal infant swallowing mechanism requires better knowledge of the normal infant swallow. Twenty-one full-term infants under six months of age were examined using videofluoroscopy of the swallowing portion of upper gastrointestinal examinations. Components of the oral and pharyngeal stages of swallowing were evaluated. Results showed high reliability between two raters in obtaining measurement data. There was variability in suck and oral transit time, which was correlated to the number of sucks per swallow. All infants appeared to move their tongue in a "stripping" motion, and collected the material in various sites in the oral cavity or oropharynx before initiation of the swallow. The incidence of nasopharyngeal reflux was low (9.5%). The majority of infants demonstrated a slight residue in their valleculae and hesitation in the cervical esophagus. These findings indicate that videofluoroscopy provides an objective and systematic method for analyzing the infant swallowing mechanism.  相似文献   
20.
Abstract: Haemoptysis in otherwise healthy children is an uncommon event. Two cases of massive haemoptysis, subsequently requiring lobectomy, are discussed. In each case, foreign vegetable matter was identified despite previously normal bronchoscopy and minimal changes on chest radiograph.  相似文献   
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