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41.
The in vitro capacity of sympathetic superior cervical ganglia (SCG) to take up [3H]choline from the extracellular medium, to synthesize acetylcholine from [3H]choline, and to release [3H]acetylcholine in response to a high K+ concentration, were examined in rats throughout a 24-h cycle. Both the release of [3H]acetylcholine and the synthesis of [3H]acetylcholine from [3H]choline exhibited significant diurnal variations, showing maxima during the first half of the night. After these maxima, nocturnal acetylcholine release and synthesis decayed to daytime levels and remained low until the end of the night. [3H]Choline uptake by rat SCG did not vary significantly throughout a 24-h period. A 1.5-h exposure of rats to darkness at the 5th hour of light phase of the daily photoperiod did not change significantly any parameter studied. A 20-min, 5-Hz, electrical stimulation of the preganglionic trunk of SCG excised from rats at noon increased significantly subsequent K+-induced [3H]acetylcholine release but did not change [3H]acetylcholine synthesis. In decentralized SCG of rats subjected to a unilateral SCG decentralization and a contralateral sham-operation 7 days earlier, [3H]acetylcholine release and synthesis were highly reduced or abolished at the decentralized side, while [3H]choline uptake remained unaltered. The present results suggest that an activation of preganglionic rat SCG neurons takes place during the first half of the scotophase. 相似文献
42.
NMDA agonists and antagonists alter the hypnotic response to ethanol in LS and SS mice 总被引:2,自引:0,他引:2
Involvement of glutamate neurotransmission in the differential response of long-sleep (LS) and short-sleep (SS) mice to acute ethanol was examined by measuring the effect of centrally administered glutamate receptor agonists and antagonists on blood ethanol concentration (BEC) at loss of righting response following intragastric administration of ethanol. NMDA coinjected with glycine, and quinolinic acid (QA), decreased sensitivity to ethanol in both lines of mice. SS mice were more sensitive to QA than were LS. The NMDA antagonists 2-amino-5-phosphonovaleric acid (APV), MK-801 and an inhibitor of glutamate synthesis, methionine sulfoximine, increased sensitivity to ethanol in both lines of mice. MK-801 effects were line dependent with SS being more sensitive. In addition, coinjection of APV, Mg++ or Zn++ with QA blocked the decrease in sensitivity seen with QA alone. These results demonstrate that NMDA agonists and antagonists alter the acute hypnotic response to ethanol in both LS and SS mice, and support the hypothesis that ethanol exerts its effects in part by altering glutamatergic neurotransmission. 相似文献
43.
44.
Postanal repair: which patients derive most benefit? 总被引:8,自引:0,他引:8
J B Rainey D R Donaldson J P Thomson 《Journal of the Royal College of Surgeons of Edinburgh》1990,35(2):101-105
Forty-two patients (37 women, 5 men; mean age 61 years) with varying degrees of anal sphincter dysfunction were treated by postanal repair. Results were analysed in relation to age, sex, presenting complaint and the results of preoperative anorectal physiological tests. Complete continence was restored in 13 (31%), while acceptable but slightly impaired control was achieved in a further 17 (40%). Twelve patients (29%) remained or became totally incontinent. The likelihood of a successful outcome was greater in those presenting with complete incontinence (77% improved) than in those retaining control of solid stool (29% improved, 29% unchanged, 43% worse). Age and sex had no effect on results but pudendal neuropathy, identified in 74% overall, slightly reduced the chance of success. In nine postoperative patients studied, neither the anorectal angle nor anal canal length bore any relation to the results of surgery. 相似文献
45.
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47.
Assault-injured Adolescents Presenting to the Emergency Department: Causes and Circumstances 总被引:1,自引:0,他引:1
48.
Kathryn E Arnold Jody L Schweitzer Barbara Wallace Monique Salter Ruth Neeman W Gary Hlady Bernard Beall 《Infection control and hospital epidemiology》2006,27(12):1377-1384
OBJECTIVE: To describe investigation of a tightly clustered outbreak of invasive group A streptococcal (GAS) disease associated with a high mortality rate in a long-term care facility (LTCF). DESIGN: Cross-sectional carriage survey and epidemiologic investigation of LTCF resident and employee cohorts. SETTING: A 104-bed community LTCF between March 1 and April 7, 2004. PATIENTS: A cohort of LTCF residents with assigned beds at the time of the outbreak. INTERVENTIONS: Reinforcement of standard infection control measures and receipt of chemoprophylaxis by GAS carriers. RESULTS: Four confirmed and 2 probable GAS cases occurred between March 16 and April 1, 2004. Four case patients died. The final case occurred during the investigation, before the patient was determined to be a GAS carrier. No case occurred during the 6 months after the intervention. Disease was caused by type emm3 GAS; 16.5% of residents and 2.4% of employees carried the outbreak strain. Disease was clustered in 1 quadrant of the LTCF and associated with nonintact skin. GAS disease or carriage was associated with having frequent personal visitors. CONCLUSIONS: Widespread carriage of a virulent GAS strain likely resulted from inadequate infection control measures. Enhanced infection control and targeted prophylaxis for GAS carriers appeared to end the outbreak. In addition to employees, regular visitors to LTCFs should be trained in hand hygiene and infection control because of the potential for extended relationships over time, leading to interaction with multiple residents, and disease transmission in such residential settings. Specific attention to prevention of skin breaks and proper wound care may prevent disease. The occurrence of a sixth case during the investigation suggests urgency in addressing severe, large, or tightly clustered outbreaks of GAS infection in LTCFs. 相似文献
49.
Tugba Yavuzsen Mellar P Davis Declan Walsh Susan LeGrand Ruth Lagman 《Journal of clinical oncology》2005,23(33):8500-8511
PURPOSE: We systematically assessed the efficacy and safety of appetite stimulants in the management of cancer-related anorexia. Literature databases were searched for randomized controlled trials of appetite stimulants in the treatment of cancer anorexia. MATERIALS AND METHODS: Studies were graded according to quality. Fifty-five studies met inclusion criteria. RESULTS: Only two drugs have evidence to support their use for anorexia (progestins and corticosteroids). There is strong evidence against the use of hydrazine sulfate. The outcomes of these trials have been mixed and patient population heterogeneous. CONCLUSION: The optimal dose, time to start, and duration of treatment for many appetite stimulants for cancer anorexia is still unknown. A more systematic approach to research methodology with universal outcome measure and prospective randomized studies are need. Combination regimens are needed but this cannot at the present time be supported by the data presented. 相似文献
50.
Bernard Stuart Declan Fox Harry Murphy Bryan Lynch J. Loftus E. Naughten I. Saul O. Sheil N. Duignan A. Jackson W. A. Gorman G. Fox T. Matthews T. Clarke Mark M. Reid H. L. Halliday B. G. McClure P. S. Thomas Michael O’Dowd Michael J. O’Dowd Kevin Connolly F. Leahy Dr. R. G. White Ruth Connolly Colm O’Herlihy Alicja Radic Dr. 《Irish journal of medical science》1986,155(6):209-212