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Preduodenal mechanisms in initiating gallbladder emptying in man 总被引:2,自引:0,他引:2
S Ellenbogen S A Jenkins J S Grime M Critchley C R Mackie J N Baxter 《The British journal of surgery》1988,75(10):940-945
The existence of preduodenal phases of gallbladder emptying in normal volunteers was investigated by evaluating the effect of sham feeding a sandwich (chew and spit) (n = 15), the sight and smell of food followed by sham feeding a cooked meal (n = 15), and gastric distension (intragastric balloon tube) (n = 9) on gallbladder emptying and comparing these responses with those after ingestion of a standard meal (n = 14). A control group given no intestinal stimuli were studied to determine the frequency of spontaneous emptying during fasting (n = 18). 99mTc-EHIDA (2,6 diethylphenylcarbamoylmethyliminodiacetic acid) was used as the biliary tracer. The frequency of gallbladder emptying during fasting was 0.0045/min. Thus, in any 20 min period emptying occurred spontaneously in only about 1 in 11 volunteers. Significant emptying (greater than 5 per cent over 20 min) occurred in 8 out of 15 volunteers after sham feeding a sandwich (P less than 0.001 versus control), in 8 out of 15 volunteers after sham feeding a cooked meal (P = 1.0 versus sandwich sham feed, n.s.), in 6 out of 9 volunteers after gastric distension (P less than 0.001 versus control) and in 14 out of 14 volunteers after meal ingestion. The rate of emptying was significantly greater in the gastric distension and meal ingestion groups compared with other groups (P less than 0.05). However, the emptying rate after sham feeding was not significantly different from spontaneous gallbladder emptying (P greater than 0.05, n.s.). There was no significant difference in time to onset of emptying between the four stimulus groups (P greater than 0.05, n.s.). These results suggest that pre-duodenal stimuli can evoke gallbladder emptying in man, although the precise physiological significance of this phenomenon remains to be established. 相似文献
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All physicians who had billed Pennsylvania Blue Shield for at least three intravenous contrast studies during 1989 were surveyed on their use of nonionic versus ionic contrast. This surveyed group represents a diversity of hospital sizes, practice types, and group sizes. Of the 383 physician groups surveyed, responses were obtained from 285. The majority of the responding groups were radiologists (94.0%). Nonionic contrast is utilized in 41.3% of all intravenous studies. Radiologists use nonionic contrast in a much greater proportion than nonradiologists (P < 0.0001), with 17.6% of radiologists utilizing nonionic contrast in all of their patients. Conversely, 75% of nonradiologists utilize ionic contrast in all of their patients. For all physician groups surveyed, 40.3% utilize nonionic for at least 50%, while 27.6% use nonionics for more than 75% of their patients. The routine use of steroid premedication prior to the injection of ionic contrast is not a common practice. The increased utilization of nonionic contrast found in this survey may reflect the cross-section of physicians and practice types surveyed or may represent changing practice patterns among physicians utilizing contrast material. 相似文献
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Helen Tager-Flusberg Kate Sullivan 《Journal of autism and developmental disorders》1994,24(5):577-586
Compared the performance of autistic and mentally retarded subjects, all of whom had passed a standard first-order test of false belief, on a new second-order belief task 12 autistic and 12 mentally retarded subjects, matched on verbal mental age (assessed by PPVT and a sentence comprehension subtest of the CELF) and full-scale IQ were given two trials of a second-order reasoning task which was significantly shorter and less complex than the standard task used in all previous research. The majority of subjects in both groups passed the new task, and were able to give appropriate justifications to their responses. No group differences were found in performance on the control or test questions. Findings are interpreted as evidence for the role of information processing factors rather than conceptual factors in performance on higher order theory of mind tasks.This study was supported by a grant from the National Institute of Deafness and Other Communication Disorders (1RO1 DC 01234). We thank Jason Barker for his extensive help with this study. We are also very grateful to the schools where the study was conducted including the League School, and the public school systems in the following towns in Massachusetts: Hanover, Hanson, Hingham, Milton, Plymouth, and Rockland. We offer special thanks to Alan Dewey, Mary Dollar, Sandy D'Giacomo, Herman Fishbein, William Griffin, Nancy Kearns, Judy Monahan, Debbie Newhall, Cay Riley, Robert Sherman, and Kathy Staska for their continued support of our research. 相似文献
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Helen Schietinger 《Death Studies》1988,12(5):481-499
People with AIDS are homeless for a variety of reasons, including financial devastation, rejection based on fear of contagion or fear of the dying process, and homeless-ness prior to a diagnosis of AIDS. The author developed and directed the Shanti AIDS Residence Program in San Francisco, the first program to provide housing for people with AIDS. This model is appropriate for single, independent people able to live cooperatively with others. It provides shared living situations for three to six people per apartment, and office staff physically maintain the houses and assure that the needs for community-based home care and other services are met. Other models are proposed for people who are physically or cognitively dependent (and require physical care or supervision in addition to housing), who are socially unable to live cooperatively with others in an unstrucured living environment (e.g., active substance users or the emotionally disturbed), or who have families (e.g., mothers with dependent children or gay men who live with their lovers). 相似文献
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