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991.
Effect of positioning on back pain after coronary angiography   总被引:5,自引:0,他引:5  
BACKGROUND: Coronary angiography is a routine cardiac diagnostic procedure in Hong Kong. Patients are restricted to bedrest after the procedure due to potential vascular complications from using a femoral approach. Many patients are required to remain on bedrest for up to 24 hours after the procedure. The effects of reducing this bedrest time is still under investigation. In the meantime, nursing interventions aimed at decreasing patient discomfort due to prolonged bedrest are feasible to implement. AIMS: The aims of this study were to evaluate the severity of back pain related to bedrest duration after coronary angiography and to compare the effects of changing patients' position in bed on their perceptions of back pain and on vascular complications. METHODS: An experimental design was used, with patients randomly assigned either to a control or experimental group. The control group received the usual care, remaining supine and flat for 8-24 hours, with the affected leg straight. The experimental group changed their body position hourly, varying between supine, right side-lying, and left side-lying during the first 7 hours after coronary angiography. RESULTS: A total of 419 patients participated in the study (control, n = 213; experimental, n = 206). Regardless of group assignment, back pain intensity increased with longer time on bedrest. In addition, the control group reported higher levels of pain at all five assessment times. Vascular complications in terms of bleeding at the femoral site were not significantly different between the control and experimental groups. CONCLUSION: The study findings suggest that patients may be able safely to change their position in bed earlier in the post-coronary angiography period than currently recommended in practice protocols. Changing position in bed may also reduce back pain, promote physical comfort, and possibly reduce patients' negative feelings toward coronary angiography.  相似文献   
992.
Rheumatic diseases are prevalent in Native American adults at rates five to seven times higher than those seen in the Caucasian population. Little, however, has been published concerning rheumatic diseases in Native American children. The authors’ work in Oklahoma and with tribes on the northern Great Plains demonstrates high rates of childhood-onset rheumatic disease in this population. Familial disease is common, and large, multiplex kindreds showing strong founder effects are likely found within specific Native American tribes. However, a deeper understanding of the genetic and environmental triggers of rheumatic disease in Native Americans will require a respect and appreciation for the specific and unique cultural and social issues that impinge on research with Native Americans and other indigenous people.  相似文献   
993.
Chondrodermatitis nodularis chronica helicis is characterized by the presence of small, intensely painful nodules on the free border of the helix of the ear with unknown origin. The lesion is typically localized unilaterally on the right ear. Pressure and trauma may play a role.  相似文献   
994.
The p53 tumor suppressor gene is one of the most frequently mutated genes in human cancer and the mutation is correlated with a poor prognosis in cancer therapy. Upregulation of multidrug resistance-associated protein 1 (MRP1) and increase in drug resistance have been found to be induced by p53 mutation. Human osteosarcoma Saos-2 cells, a p53-null cell line, was transfected with p53 with mutations at codon 143 (V to A), 175 (R to H), 248 (R to W), 273 (R to H) and 281 (D to G). Among the different transfectants, overexpression (about 42-fold) of MRP1 was detected in p53-R175H cells. Furthermore, the p53-R175H cells were 2.5-fold more resistant to doxorubicin (DOX) and had a 4-fold greater DOX efflux rate than the control cells 1 h after DOX treatment. Transfection with antisense MRP1 oligonucleotides demonstrated a DOX sensitization effect (about 2-fold) in p53-R175H transfectants but not in control cells. In addition, transfection with antisense p53 oligonucleotides greatly suppressed MRP1 expression and reversed DOX resistance in p53-R175H cells but had no effect in control cells. The results suggested that p53-R175H might induce MRP1 expression and DOX resistance in cells.  相似文献   
995.
Tumor oxygenation has long been recognized as a significant factor influencing cancer therapy. We recently established a novel magnetic resonance in vivo approach to measuring regional tumor oxygen tension, FREDOM (Fluorocarbon Relaxometry Using Echo Planar Imaging for Dynamic Oxygen Mapping), using hexafluorobenzene (HFB) as the reporter molecule. We have now investigated oxygen dynamics in the two Dunning prostate R3327 rat tumor sublines, AT1 and H. FREDOM revealed considerable intratumoral heterogeneity in the distribution of pO(2) values in both sublines. The anaplastic faster-growing AT1 tumors were more hypoxic compared with the size-matched, well-differentiated, and slower-growing H tumors. Respiratory challenge with oxygen produced significant increases in mean and median pO(2) in all the H tumors (P<.001), but no response in half of the larger AT1 tumors (>3 cm(3)). Immunohistochemical studies using the hypoxia marker, pimonidazole, and the vascular endothelial cell marker, CD31, confirmed that the H tumors had more extensive vasculature and less hypoxia than the AT1 tumors. These results further validate the utilization of FREDOM to monitor tumor oxygenation and concur with the hypothesis that the level of hypoxia is related to tumor growth rate and poor vascularity.  相似文献   
996.
997.
Liberase is a highly purified blend of collagenases that has been specifically developed to eliminate the numerous problems associated with the conventional use of crude collagenase when isolating islet-like cell clusters (ICCs) from pancreases of different species. The influence of Liberase on yield, size, viability, and function of ICCs has been documented when this enzyme was used to digest adult but not fetal pancreases. In this study, we compared the effects of collagenase and Liberase on fetal pig ICCs. A total of eight fetal pig pancreas digestions were analyzed. Fetuses were obtained from Large White Landrace pigs of gestational age 80 +/- 2.1 days. The pancreases were digested with either 3 mg/ml collagenase P or 1.2 mg/ml Liberase HI. The time taken to digest the pancreas was shorter for collagenase when compared with Liberase (22 +/- 2 vs. 31 +/- 2 min). The size of ICCs was similar for both collagenase (83 +/- 0.5 microm) and Liberase (79 +/- 0.4 microm) as was the number of ICCs produced per pancreas (7,653 +/- 1,297 vs. 8,101 +/- 1,177). Viability, as assessed using fluorescent markers, was slightly greater for Liberase (79 +/- 1% vs. 76 +/- 1%, p < 0.05). Responsiveness to beta-cell stimulus (20 mM KCl) was similar for both methods of isolation, as was the insulin content of the ICCs, both in vitro and at I month after transplantation of 1,500 ICCs beneath the renal capsule of immunoincompetent mice. Despite the high content of endotoxins in collagenase, the above results show that this enzyme was equally as efficient as Liberase in isolating functional ICCs from fetal pig pancreas.  相似文献   
998.
The purpose of this study was to develop a spike-related functional magnetic resonance (MR) imaging method to detect epileptic brain activity. Correlations between simultaneous spike-related functional MR imaging and electroencephalographic (EEG) recordings were performed in 10 patients with focal epilepsy. Postprocessing techniques were implemented to eliminate contamination of the EEG recording from ballistocardiography and the echo-planar MR imaging sequence. A diagnostic EEG recording was achieved during functional MR imaging. Spike location correlated with the site of blood oxygen level-dependent signal increase. Spike-related functional MR imaging is a promising technique for detecting focal epileptic brain activity.  相似文献   
999.
Brain-derived neurotrophic factor (BDNF), its signal transduction receptor trkB, and its downstream effector, synapsin I, were measured in the hippocampus and occipital cortex of young animals after fluid-percussion brain injury (FPI). Isofluorane anaesthetized postnatal day 19 rats were subjected to a mild lateral FPI or sham injury. Rats were sacrificed at 24 h, 7 days, or 14 days after injury in order to determine mRNA expression. Additional animals were sacrificed at 7 and 14 days after injury for protein analysis. Only FPI animals exhibited hemispheric differences in BDNF levels. These animals exhibited a contralateral increase, ranging from 40% to 75%, in BDNF mRNA within both the hippocampus and occipital cortex at 24 h and 7 days after injury. The increase in message within the occipital cortex was accompanied by an increase in BDNF protein at 7 and 14 days after injury. However, hippocampal BDNF protein increased in both hemispheres at postinjury day 7 and was restricted to the ipsilateral hippocampus at postinjury day 14. At postinjury day 7, both trkB and synapsin I mRNA expression increased ipsilaterally and decreased contralaterally in the occipital cortex. In addition, synapsin I phosphorylation was increased by 20% in the ipsilateral cortex and by 30% in the hippocampus on this day. These results indicate that the developing brain responds to a mild injury by modifying factors related to synaptic plasticity and suggest that regions remote from the site of injury express neurotrophic signals potentially needed for compensatory responses.  相似文献   
1000.
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