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101.
A. Ian Smith Catherine A. Wallace Lain J. Clarke John W. Funder 《Journal of neuroendocrinology》1989,1(5):357-362
In the sheep, unlike many other species, a significant proportion (>25%) of immunoreactive β-endorphin in the anterior pituitary is post-translationally modified to opioid-inactive, α-N-acetylated forms. In a study to determine the precise molecular nature of α-N-acetylated β-endorphin immunoreactivity, we noted a striking difference in high-performance liquid chromatography profiles of anterior pituitary extracts between sheep killed on the farm, and age-, sex- and strain-matched slaughterhouse animals. These altered patterns of a-N-acetylated β-endorphin processing were reproduced in farm animals by chronic (≤ 4 days) treatment with the synthetic glucocorticoid dexamethasone; in contrast dexamethasone had no effect on a-N-acetylated β-endorphin processing in hypothalamo-pituitary disconnected sheep. These data suggest that (1) the change in processing is a stress response, mediated by prolonged glucocorticoid exposure, (2) this effect is central, rather than a direct effect on the pituitary, and (3) the relative abundance of various peptide sequences in slaughterhouse-derived material may not reflect their abundance under more physiological conditions. 相似文献
102.
103.
JO MANION RN MA CNAA 《Journal of obstetric, gynecologic, and neonatal nursing : JOGNN / NAACOG》1986,15(2):103-108
A documentation system that facilitates accurate and complete recording is needed by every obstetric/neonatal nursing service. Developing an individualized system is a major undertaking. However, specific steps can be taken to ease the process. These steps are described, beginning with the assessment phase and concluding with evaluation. 相似文献
104.
Najat MA Farsi 《BMC oral health》2007,7(1):15
Background
This study aimed to investigate the signs of oral dryness in relation to different salivary variables and to correlate subjective complaints of oral dryness with salivary flow rate. 相似文献105.
106.
Guoping Lian Mark E Malone Jenny E Homan Ian T Norton 《Journal of controlled release》2004,98(1):139-155
This paper presents a mathematical model of in-mouth volatile release from gelled emulsion particles dispersed in a continuous aqueous phase. Data based on APCI MS-Breath analysis is presented to demonstrate the effect of particle size, oil content and oil-water partition coefficients. It is shown that in-mouth release of aroma from the dispersion of gelled emulsion particles follows a two-component kinetic equation with fast and slow components. Both the fast and slow rate constants depend on the particle size, oil content and oil water partition coefficient of the aroma. The relative amount of aroma contributing to the fast and slow components also depends on the size of the particles. In order to understand this unexpected behaviour, an analytical model was developed that considers the interplay between the mass transfer of flavour across the interface of the particles and that across the air-liquid interface. Analytical expressions for the two rate constants and the relative ratio of aroma contributing to the fast component have been derived. From this model, three regimes of in-mouth release of aroma from the dispersion of gelled emulsion particles were identified including, the emulsion regime, the transition regime and the gel particle regime. In the emulsion regime, changes in the size of gelled emulsion particles had negligible impact on the overall release. In the transition regime, the release was controlled by the interaction of flavour transfer from the particles with that across the air-water interface. In the gel particle regime, aroma release at long times was governed by the particles and that at short times was governed by the air-water interface, and the two processes were fully decoupled. A simple relationship was derived for the critical size above which the release of aroma from the dispersion of gelled emulsion particles is affected by the size of the particles. 相似文献
107.
The purpose of this pilot study was to observe both relaxed and deep breathing patterns in a convenience sample to determine the incidence of normal versus faulty patterns of respiration. These observations were then combined with respondent answers to a survey on pain history to determine if there is any correlation between faulty breathing and musculo-skeletal pain patterns. If such a correlation can be made, then we propose that clinicians working with chronic pain patients may have improved outcomes if they address and correct faulty breathing patterns. Based on this study, it is suggested to include the evaluation and treatment of faulty respiration in the rehabilitation of chronic musculo-skeletal conditions, most notably cervical pain. 相似文献
108.
Alain Deschamps Ian Kaufman Alana Geist Steven S. B. Backman Karen Loo 《Journal canadien d'anesthésie》2007,54(3):183-189
PURPOSE: To evaluate the correlation between the progression of somatosensory blockade and changes in autonomic outflow following the onset of labour epidural analgesia. METHODS: Twelve labouring parturients consented to participate in the study. Baseline electrocardiogram, blood pressure (BP) and respiratory rate were recorded for ten minutes. The epidural consisted of 0.125% bupivacaine with 50 microg of fentanyl (total volume 20 mL). Measurements were repeated for ten minutes after initiation of the block. The level of sensory block was measured bilaterally with loss of sensation to ice at two-minute intervals. Wavelet transform was used to obtain heart rate (HR) and BP variability every two minutes following the loading dose of epidural medication. High frequency power of HR variability was used to assess changes in parasympathetic activity. The total power of BP variability was used to assess changes in sympathetic activity. A nonparametric repeated measures ANOVA was used for the variability data, and a Spearman rank correlation test was used to evaluate the relationship between the sensory block and HR and BP variability. RESULTS: The sensory block progressed to T9 at ten minutes post-epidural and was the mirror image of the decrease in total power of BP variability. High frequency power of HR variability increased to a plateau at six minutes post-epidural. A significant correlation was found between the increase in sensory block and the observed decrease in BP variability (r = -1.000, P = 0.0028). CONCLUSION: In this study of labouring parturients, BP variability correlated with the progression of both sympathetic and somatosensory block following epidural anesthesia, while HR variability was shown to be a surrogate marker of increased parasympathetic activity. 相似文献
109.
Dorit Naot Usha Bava Brya Matthews Karen E Callon Gregory D Gamble Michael Black Sarah Song Rocco P Pitto Tim Cundy Jill Cornish Ian R Reid 《Journal of bone and mineral research》2007,22(2):298-309
Paget's disease is a focal condition of bone. To study changes in cells within pagetic lesions, we cultured osteoblasts and stromal cells from 22 patients and compared gene expression in these cells to cells from healthy bone. We identified several differentially regulated genes, and we suggest that these changes could lead to the formation of the lesions. INTRODUCTION: Paget's disease is a focal condition of bone of unknown cause. Although it is regarded as primarily an osteoclast disorder, the tight coupling of the activity of osteoclasts and osteoblasts suggests that the osteoblast could play a key role in its pathogenesis. The aim of the study was to identify possible changes in pagetic osteoblasts and stromal cells that might contribute to the development of pagetic lesions. MATERIALS AND METHODS: Candidate genes were identified based on known bone cell regulators, supplemented with microarray analysis. Gene expression was determined by real-time PCR in primary cultures of osteoblasts and bone marrow stromal cells from pagetic patients and control subjects. Concentrations of secreted proteins were determined by ELISA. RESULTS: Dickkopf1 mRNA and protein levels were increased in both pagetic osteoblast and stromal cell cultures, and interleukin (IL)-1 and IL-6 were overexpressed in pagetic osteoblasts. These changes parallel recent findings in myeloma bone disease, which shares some clinical similarities with Paget's disease. Alkaline phosphatase was overexpressed, and bone sialoprotein and osteocalcin were underexpressed in pagetic osteoblasts, consistent with their circulating levels in pagetic patients. It is hypothesized that overexpression of Dickkopf1, IL-1, and IL-6 would result in stimulation of osteoclast proliferation and inhibition of osteoblast growth, leading to the development of the characteristic lytic bone lesions. By stimulating osteoblast differentiation, Dickkopf1 and IL-6 may also promote mineralization, leading to the conversion of lytic lesions to sclerotic. CONCLUSIONS: These findings suggest that dysregulated gene expression in pagetic osteoblasts could cause the changes in bone cell number and function characteristic of Paget's disease. 相似文献
110.
Chronobiological characteristics of postoperative pain: Diurnal variation of both static and dynamic pain and effects of analgesic therapy 总被引:2,自引:1,他引:1
BACKGROUND: Previous postoperative investigations report morning peaks in analgesic administration. However, few studies have examined diurnal variation of both pain and analgesic consumption and little is known about dynamic pain in this context. METHODS: The diurnal pattern of postoperative pain is described using pain intensity and analgesic consumption data from a recently published hysterectomy trial. RESULTS: In the presence of patient-controlled analgesia with morphine, pain at 8 a.m. was significantly higher (P<0.05) than at noon, 4 p.m. or 8 p.m. on postoperative day one (for rest pain and pain evoked by sitting, forced expiration and cough) and on postoperative day two (for pain evoked by forced expiration and cough only). This temporal pattern was observed both with and without the co-administration of non-opioid analgesics (gabapentin and/or rofecoxib). Morphine use during the four hours preceding 8 a.m. on either postoperative day was not significantly lower than any of the other corresponding time intervals. CONCLUSIONS: Based on data from our post-hysterectomy analgesic clinical trial, static and dynamic pain in the morning appears to be more intense than pain later in the day. This pattern was observed in the presence of substantial nocturnal morphine use. Based on these and other previous observations, specifically designed investigations are needed to better characterize the clinical, neurohormonal and neurophysiological features of postoperative circadian pain variation - including pain during sleeping hours. If the above observations are replicated, future study of nocturnal sustained-release opioids as well as time-shifting the administration of non-opioid co-analgesic drugs to the very early morning may be warranted. 相似文献