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Pain management presents exciting opportunities for nurse anesthetists. Today there are thousands of pain clinics and pain services dedicated to the diagnosis and treatment of chronic and acute pain. By becoming familiar with the principles involved in the management of chronic and acute pain, the different treatment modalities available, and the organization of pain clinics and pain services, nurse anesthetists will be able to take advantage of the opportunities they provide.  相似文献   
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Bromobenzene (800 mg/kg, ip) caused severe liver necrosis with massive hemorrhage in the golden Syrian hamster within the first 24 hr. Kidney injury was also observed. Treatment with N-acetylmethionine (NAM) at an ip dose of 1200 mg/kg at 5 hr after bromobenzene administration significantly protected the liver and kidney against injuries. Plasma glutamate pyruvate transaminase and blood urea nitrogen levels were substantially decreased in the NAM-treated animals. Histological evaluations confirmed these results. When the urinary neutral and phenolic metabolites of bromobenzene from NAM-treated and untreated hamsters were isolated and compared by GC and GC/MS, a striking result was observed in terms of O- and S-methylated thiol-containing metabolite formation. The NAM-treated animals showed approximately a 8- to 14-fold increase in the excretion of the four isomeric O- and S-methylated bromothiocatechols. These thiocatechols, which are now known to be the 3,4-series metabolites of bromobenzene, can undergo methylation at either the thiol or the hydroxyl functional group. The excretion of 3-S- and 4-S-methylated bromodihydrobenzene thiolols was also increased significantly in the NAM-treated hamster, but other neutral and phenolic metabolites were relatively unchanged. These results suggest that bromobenzene toxicity in the Syrian hamster may be associated with impaired methylation capabilities, an impairment that could be due to methionine and glutathione depletion.  相似文献   
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Doppler sonography of the fetal descending aorta, renal artery, middle cerebral artery and umbilical artery in a population of 74 fetuses with a abdominal circumference below the fifth percentile of the reference limits were done. All fetuses were free from structural and chromosomal abnormalities. The pulsatility- and the resistance indices as well as the ratios between these indices from peripheral and cerebral vessels were calculated and correlated to the fetal distress. The measurement of the pulsatility index of the middle cerebral artery provided the best results in predicting the development of fetal distress. Better results were achieved by the use of ratios of pulsatility-indices of various vessels than by the examination of the vessels alone. Our results suggest the usefulness of the examination of the middle cerebral artery and their ratios compared to the renal artery.  相似文献   
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Sheep pulmonary adenomatosis (SPA) is a contagious bronchiolo-alveolar carcinoma of sheep associated with an exogenous type D/B retrovirus known as jaagsiekte sheep retrovirus (JSRV). SPA represents a unique model for lung cancer, and studies on its aetiopathogenesis can provide further insight into the mechanisms of epithelial neoplasms.  相似文献   
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Stress has a significant influence on the function of the human organism. A simple, rapid, inexpensive, and reliable marker for stress would therefore be of great value. We have recently noted that stress increases the state of leukocyte adhesiveness and aggregation in the peripheral blood. We evaluated 64 patients who had various degrees of congestive heart failure, a condition known to induce a state of physiologic stress, to verify whether a relation exists between the intensity of the stress response and the magnitude of leukocyte adhesiveness. Included in the 64 were 53 patients without congestive heart failure, 23 with compensated failure, 22 with significant congestive heart failure, and 19 with florid pulmonary edema. The percentage of aggregated leukocytes in these four group was 6% +/- 4%, 6% +/- 4%, 10.5% +/- 5%, and 15% +/- 14%. Values for the third and fourth group differed in a statistically significant way. Thus, with further investigation into additional stress-inducing conditions, the state of leukocyte adhesion and aggregation may prove to be a reliable marker for the detection of stress and an inexpensive tool for quantifying its severity.  相似文献   
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