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91.
c-Fos has been used as a marker for activity in the spinal cord following noxious somatic or visceral stimulation. Although the viscera receive dual afferent innervation, distention of hollow organs (i.e. esophagus, stomach, descending colon and rectum) induces significantly more c-Fos in second order neurons in the nucleus of the solitary tract and lumbosacral spinal cord, which receive parasympathetic afferent input (vagus, pelvic nerves), than the thoracolumbar spinal cord, which receives sympathetic afferent input (splanchnic nerves). The purpose of this study was to determine the contribution of sympathetic and parasympathetic afferent input to c-Fos expression in the nucleus of the solitary tract and spinal cord, and the influence of supraspinal pathways on Fos induction in the thoracolumbar spinal cord. Noxious gastric distention to 80 mmHg (gastric distension/80) was produced by repetitive inflation of a chronically implanted gastric balloon. Gastric distension/80 induced c-Fos throughout the nucleus of the solitary tract, with the densest labeling observed within 300 microns of the rostral pole of the area postrema. This area was analysed quantitatively following several manipulations. Gastric distension/80 induced a mean of 724 c-Fos-immunoreactive nuclei per section. Following subdiaphragmatic vagotomy plus distention (vagotomy/80), the induction of c-Fos-immunoreactive nuclei was reduced to 293 per section, while spinal transection at T2 plus distention (spinal transection/80) induced a mean of 581 nuclei per nucleus of the solitary tract section. Gastric distension/80 and vagotomy/80 induced minimal c-Fos in the T8-T10 spinal cord (50 nuclei/section), but spinal transection/80 induced 200 nuclei per section. Repetitive bolus injections of norepinephrine produced transient pressor responses mimicking the pressor response produced by gastric distension/80. This manipulation induced minimal c-Fos in the nucleus of the solitary tract and none in the spinal cord. It is concluded that noxious visceral input via parasympathetic vagal afferents, and to a lesser extent sympathetic afferents and the spinosolitary tract, contribute to gastric distention-induced c-Fos in the nucleus of the solitary tract. The induction of c-Fos in the nucleus of the solitary tract is significantly greater than in the viscerotopic segments of the spinal cord, which is partially under tonic descending inhibition, but is not subject to modulation by vagal gastric afferents. Distention pressures produced by noxious gastric distention are much greater than those produced during feeding, suggesting that c-Fos induction in the nucleus of the solitary tract to noxious distention is not associated with physiological mechanisms of feeding and satiety. The large vagal nerve-mediated induction of c-Fos in the nucleus of the solitary tract following gastric distension suggests that parasympathetic afferents contribute to the processing of noxious visceral stimuli, perhaps by contributing to the affective-emotional component of visceral pain. 相似文献
92.
Two analogues of the potent 5-HT1A antagonist WAY 100635 have been synthesized and radiolabelled with 18F, namely N-[2-[4-(2-2'-[18F] fluoroethoxyphenyl)-1-piperazinyl]ethyl]-N-(2-pyridinyl)cyclohe xan e carboxamide ([18F]FEC) and N-[2-[4-(2-3'-[18F] fluoropropoxyphenyl)-1-piperazinyl]ethyl]-N-(2-pyridinyl)cycloh exa ne carboxamide ([18F]FPC). Biodistribution studies in rats showed selective uptake of both radiotracers in regions known to be rich in 5-HT1A receptors following i.v. injection. The ratio of radioactivity in hippocampus to that in the cerebellum was 5.5 (for [18F]FEC) and 7.5 (for [18F]FPC) at 60 min postinjection. Regional brain heterogeneity of radioactivity could be abolished by pretreatment with WAY 100635 and FPC but was unaffected by pretreatment with a variety of drugs including ketanserin, sulpiride, and SCH 23390. These results are compared vis-a-vis with those obtained using [11C]WAY 100635 to evaluate [18F]FEC and [18F]FPC as potential radiotracers for imaging 5-HT1A receptors by positron emission tomography. 相似文献
93.
94.
Between 1977 and 1983, 64 infected total knee replacements in 60 patients were treated with a 2-stage protocol for reimplantation. The clinical results and survivorship were determined at an average followup of 7.5 years (range, 2-17 years). Surgical protocol included removal of the prosthesis and all cement with thorough debridement of bone and soft tissues. This was followed by 6 weeks of parenteral antibiotics and then reimplantation of a new prosthesis. At followup, 6 knees (9%) had become reinfected, but only 2 with the same organism. Four knees had been revised: 3 for aseptic loosening and 1 for a periprosthetic femur fracture. Two other knees were impending failures due to aseptic loosening. The average Hospital for Special Surgery knee score was 78 points with 18 excellent, 28 good, 13 fair, and 5 poor results. Seventy-eight percent of patients were satisfied with the overall result of their reimplanted prosthesis and 95% think that they made the right decision in undergoing total knee arthroplasty. The 10-year predicted survivorship of 2-stage reimplantation is 77.4%. Two-stage reimplantation with a 6-week course of parenteral antibiotics is an effective means to eradicate deep infection and to provide a functional knee. The long term functional results and overall survivorship are comparable with the results of revision of aseptic failed total knee arthroplasty. 相似文献
95.
LS Dean M Mickel R Bonan DR Holmes WW O'Neill IF Palacios S Rahimtoola JN Slater K Davis JW Kennedy 《Canadian Metallurgical Quarterly》1996,28(6):1452-1457
OBJECTIVES: This study reports the long-term outcome of patients undergoing percutaneous balloon mitral commissurotomy who were enrolled in the National Heart, Lung, and Blood Institute (NHLBI) Balloon Valvuloplasty Registry. BACKGROUND: The NHLBI established the multicenter Balloon Valvuloplasty Registry in November 1987 to assess both short- and long-term safety and efficiency of percutaneous balloon mitral commissurotomy. METHODS: Between November 1987 and October 1989, 736 patients > or = 18 years old underwent percutaneous balloon mitral commissurotomy at 23 registry sites in North America. The maximal follow-up period was 5.2 years. RESULTS: The actuarial survival rate was 93 +/- 1% (mean +/- SD), 90 +/- 1.2%, 87 +/- 1.4% and 84 +/- 1.6% at 1, 2, 3 and 4 years, respectively. Eighty percent of the patients were alive and free of mitral surgery or repeat balloon mitral commissurotomy at 1 year. The event-free survival rate was 80 +/- 1.5% at 1 year, 71 +/- 1.7% at 2 years, 66 +/- 1.8% at 3 years and 60 +/- 2.0% at 4 years. Important univariable predictors of actuarial mortality at 4 years included age > 70 years (51% survival), New York Heart Association functional class IV (41% survival) and baseline echocardiographic score > 12 (24% survival). Multivariable predictors of mortality included functional class IV, higher echocardiographic score and higher postprocedural pulmonary artery systolic and left ventricular end-diastolic pressures (p < 0.01). CONCLUSIONS: Percutaneous balloon mitral commissurotomy has a favorable effect on the hemodynamic variables of mitral stenosis, and long-term follow-up data suggest that it is a viable alternative with respect to surgical commissurotomy in selected patients. 相似文献
96.
LM Hansen FR Batzer JN Gutmann SL Corson MP Kelly B Gocial 《Canadian Metallurgical Quarterly》1996,11(3):486-489
A prospective measurement of follicle stimulating hormone (FSH) and oestradiol between cycle days 2 and 5 was conducted to investigate the intra- and inter-cycle variability in a healthy population of women with regular menstrual intervals. Daily serum samples were obtained from 44 women for a total of 66 cycles on cycle days 2, 3, 4 and 5. FSH concentrations were consistent on all cycle days measured. Oestradiol concentrations on cycle day 2 were not different from cycle day 3, but concentrations on cycle day 4 and cycle day 5 were statistically different from both cycle day 2 and cycle day 3 by analysis of variance (P < or = 0.05). Evaluation of functional ovarian reserved by cycle day 3 FSH measurement has become the standard in most assisted reproductive technology programmes. The recent change in FSH standardization coupled with the inflexibility of cycle day 3 testing has led to a re-evaluation of testing protocols. Cycle day 3 appears to have emerged as a dictum because most ovulation induction protocols are initiated on cycle day 3, 4 or 5. Flexibility of sampling day can be introduced as suggested by these results. The additional information ascertained from oestradiol testing as applied to evaluation of ovarian reserve warrants further investigation. 相似文献
97.
Previous studies have shown that the administration of certain calcium channel blocking drugs (at an appropriate time point) can reduce the severity of atherosclerotic lesion formation. This study was undertaken to determine if the administration of isradipine would reverse established lesions produced by feeding rabbits an atherogenic diet. Rabbits were fed cholesterol for three weeks and examined directly, or after being left for a four week washout period, with or without a daily oral supplement of isradipine. Fatty streaks were well established after three weeks of cholesterol feeding and were more extensive at the end of the washout period, as indicated by gross changes in the volume of the intima per unit length of aorta. When isradipine was administered during the washout period, the volume of the intima per unit length of aorta fell to levels below those produced by cholesterol feeding for three weeks alone. The major components of the lesions affected to accommodate these changes were the foam cells and myointimal cells; these were examined in detail using morphometry and lipid cytochemistry. The mean volume of intima/cm of aorta occupied by foam cells and myointimal cells both fell by more than 60% to levels lower than those found after three weeks of cholesterol feeding alone. The volume of the extracellular space of the intima occupied by cytochemically demonstrable unesterified and esterified cholesterol was reduced by isradipine administration as was that of foam cells, all to levels lower than those found after three weeks of cholesterol feeding alone. These data indicate that the administration of isradipine during a washout period, after cholesterol feeding, can promote the regression of fatty streak lesions. 相似文献
98.
99.
JN Aaron CC Carlisle MA Carskadon TJ Meyer NS Hill RP Millman 《Canadian Metallurgical Quarterly》1996,19(9):707-710
Our laboratory previously reported continuously monitored peak sound levels in several areas at Rhode Island Hospital. The number of sound peaks greater than 80 A-weighted decibels (dBA) was found to be high in the intensive and intermediate respiratory care unit (IRCU) areas, even at night. Environmental noise of this magnitude is potentially sleep-disruptive. Therefore, we hypothesized that nocturnal peak sound levels of > or = 80 dBA would be associated with an increase in EEG arousals from sleep in patients in the IRCU. Six patients underwent sleep monitoring while environmental peak sound levels were continuously recorded. Each 8-hour period (2200 to 0600 hours) was broken down into 30-minute segments. If there were 10 minutes or more of wakefulness in a segment, that segment was dropped from further analysis. Of the remaining 61 segments, there was a very strong correlation (r = 0.57, p = 0.0001) between the number of sound peaks of > or = 80 dBA and arousals from sleep. These 61 periods were then classified as quiet, moderately loud, and very loud based on the number of sound peaks (< or = 5, 6-15, and > 15, respectively). Analysis of variance revealed a significant difference between the number of arousals (p = 0.001) in quiet periods and that in very loud periods. We conclude that environmental noise may be an important cause of sleep disruption in the IRCU. 相似文献
100.
The predictability of personality for psychological well-being in centenarians when compared to sexagenarians and octogenarians was investigated. Multiple regressions were computed to examine the separate and joint effects of personality traits and states upon morale. Results indicated that low tension and high extraversion predicted high morale for centenarians. Guilt was the most important personality state predicting morale for the 60s age group, and control variables gender and health were significant for the 80s age group. The assessment of personality traits and states has important implications for working with centenarians and other older adults to maintain or improve their subjective well-being. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献