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The purpose of this study was to identify the optimal knot construction for interrupted dermal sutures. A synthetic braided absorbable suture, sizes 3-0 and 5-0, was selected for this evaluation. With reproducible mechanical performance tests, we determined that the construction of secure knots without ears required one additional throw as compared with secure knots with 3-mm ears. The direction of applied tension did not alter knot security, with the exception of granny knots, which required an extra throw when tension was applied parallel to the suture loop. Because interrupted dermal knot construction is accomplished without knot ears and with an applied tension parallel to the wound, one additional throw must be added to the knot to ensure knot security. 相似文献
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We have designed, developed, and tested a very promising thermal image analysis method for polygraph testing. The method achieved a correct classification rate of CCR= 84% on the test population to our avail. This method, once refined, can serve as an additional channel for increasing the reliability and accuracy of traditional polygraph examination. We extract subtle facial temperature fluctuation patterns through nonlinear heat transfer modeling. The modeling transforms raw thermal data to blood flow rate information. Then, we use the slope of the average periorbital blood flow rate as the feature of a binary classification scheme. The results come to support our previous laboratory findings about the importance of periorbital blood flow in anxious states. 相似文献
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This article argues that an iconic event in the history of helping research--the story of the 38 witnesses who remained inactive during the murder of Kitty Genovese--is not supported by the available evidence. Using archive material, the authors show that there is no evidence for the presence of 38 witnesses, or that witnesses observed the murder, or that witnesses remained inactive. Drawing a distinction between the robust bystander research tradition and the story of the 38 witnesses, the authors explore the consequences of the story for the discipline of psychology. They argue that the story itself plays a key role in psychology textbooks. They also suggest that the story marks a new way of conceptualizing the dangers of immersion in social groups. Finally, they suggest that the story itself has become a modern parable, the telling of which has served to limit the scope of inquiry into emergency helping. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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JF Levine CS Apperson P Howard M Washburn AL Braswell 《Canadian Metallurgical Quarterly》1997,34(6):594-598
Previously archived museum specimens of lizards collected throughout North Carolina were examined for Ixodes scapularis (Say). Lizards (n = 1,349) collected in 80 of North Carolina's 100 counties were examined. Lizards with ticks were collected in 23 (29%) of the 80 counties from which lizards were examined. I. scapularis was detected on 8.7% (n = 117) of the lizards and was the sole species of tick obtained from lizards. Immature ticks were most frequently found on the southeastern five-lined skink, Eumeces inexpectatus, and the eastern glass lizard, Ophisaurus ventralis. Larvae were most frequently found on the six-lined racerunner, Cnemidophorus sexlineatus. One C. sexlineatus harbored 177 larvae and 2 nymphs. Nymphs were most frequently observed on E. inexpectatus. The majority of counties (chi 2, P < 0.01) where ticks were found on lizards were in the Coastal Plain. 相似文献
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FM Apter P Michetti LS Winner JA Mack JJ Mekalanos MR Neutra 《Canadian Metallurgical Quarterly》1993,61(12):5279-5285
Secretory immunoglobulin A (IgA) antibodies (sIgA) directed against cholera toxin (CT) and surface components of Vibrio cholerae are associated with protection against cholera, but the relative importance of specific sIgAs in protection is unknown. A monoclonal IgA directed against the V. cholerae lipopolysaccharide (LPS), secreted into the intestines of neonatal mice bearing hybridoma tumors, was previously shown to provide protection against a lethal oral dose of 10(7) V. cholerae cells. We show here that a single oral dose of 5 to 50 micrograms of the monoclonal anti-LPS IgA, given within 2 h before V. cholerae challenge, protected neonatal mice against challenge. In contrast, an oral dose of 80 micrograms of monoclonal IgA directed against CT B subunit (CTB) failed to protect against V. cholerae challenge. A total of 80 micrograms of monoclonal anti-CTB IgA given orally protected neonatal mice from a lethal (5-micrograms) oral dose of CT. Secretion of the same anti-CTB IgA antibodies into the intestines of mice bearing IgA hybridoma backpack tumors, however, failed to protect against lethal oral doses of either CT (5 micrograms) or V. cholerae (10(7) cells). Furthermore, monoclonal anti-CTB IgA, either delivered orally or secreted onto mucosal surfaces in mice bearing hybridoma tumors, did not significantly enhance protection over that provided by oral anti-LPS IgA alone. These results demonstrate that anti-LPS sIgA is much more effective than anti-CT IgA in prevention of V. cholerae-induced diarrheal disease. 相似文献
9.
Severe symptomatic hypomagnesemia (0.15 mmol/L [0.3 mEq/L]) and hypocalcemia (1.47 mmol/L [5.9 mg/dL]) occurred in a 4-week-old infant coincidental with correction of a severe renal tubular acidosis with alkali therapy. The patient had no evidence of gastrointestinal abnormality and magnesium (Mg) intake was adequate for age and weight. Extreme renal conservation of Mg was observed, supporting the presence of Mg depletion. We suggest that Mg depletion in this infant occurred due to acidosis-induced bone demineralization and that symptomatic hypomagnesemia was precipitated by rapid remineralization accompanying correction of systemic acidosis. This patient represents a novel case of hungry bone syndrome (HBS). Since HBS has not been described previously in patients with acidosis undergoing therapy, several other factors may have contributed to this patient's severe hypomagnesemia, namely, prematurity, twin status, severity of acidosis, rapidity of correction of acidosis, catch-up growth and calcium supplementation. Clinicians should be vigilant for HBS in infants with severe acidosis undergoing alkali therapy. 相似文献
10.
Studies of adults, children, and laboratory animals suggest an association between lead exposure and hearing loss. A causal relationship might direct mandated medical surveillance of lead-exposed workers to include audiometric testing. A cross-sectional, computerized dataset was obtained from a private occupational health screening company to examine the relationship between blood lead level and hearing loss. Audiometry and blood lead results were available for 183 workers. A statistically significant correlation was found between blood lead level and an elevated hearing threshold at 400 Hz (P = 0.03); no other frequencies showed such a correlation. This finding suggests either an interaction between nose exposure and lead, interaction of other exposure factors (such as cigarette smoking), or that factors other than biomechanical ones render the organ of Corti more susceptible at 4000 Hz. Further evaluation of these questions should be undertaken. Computerized databases created for worker surveillance may be a source for data useful for examining other causal connections in occupational settings. 相似文献