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1.
目的快速鉴定血培养中的金黄色葡萄球菌和凝固酶阴性葡萄球菌(CoNS),结合临床快速判定是否为污染菌。方法采用荧光原位杂交法鉴定血培养中的金黄色葡萄球菌和CoNS,杂交结果若为CoNS,根据临床资料进行判断,并与文献推荐的污染判断法进行结果比较。结果探针的特异性经由标准菌株和临床分离菌株证实。金黄色葡萄球菌探针的特异性和敏感性均为100%,GoNS探针的特异性和敏感性分别为100%和95.5%。179株CoNS中117株判断为污染菌,污染率为68%,与文献推荐的污染判断方法一致。结论荧光原位杂交法适用于血培养中的金黄色葡萄球菌和CoNS的快速鉴定,以排除CoNS污染。 相似文献
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C M Mond D B Walters R S Stricoff E M Prescott A T Prokopetz 《American Industrial Hygiene Association journal》1987,48(10):823-829
A human factors engineering analysis of a chemical containment laboratory was performed to develop appropriate standards for future laboratory design. In order to perform this evaluation, a state-of-the-art facility was studied in depth. Measurements and observations were made of key operating areas. In addition, technicians were observed and interviewed as they performed various tasks. Compiled data were compared to existing ergonomic standards. The occupational implications of instituting ergonomically developed laboratory design standards are as follows: increased worker health, safety and productivity, improved work quality and reduced stress. 相似文献
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偏头痛大鼠脑内5-羟色胺1F和诱导型一氧化氮合酶基因的表达变化及针刺的干预效应 总被引:3,自引:0,他引:3
目的:前期实验已证实针刺治疗偏头痛疗效优越。观察针刺对偏头痛大鼠脑内5-羟色胺1F和诱导型一氧化氮合酶mRNA表达的调控作用。方法:实验于2005-11/2006-05在中南大学湘雅医院中西医结合研究所实验室完成。①选用SD大鼠40只,按随机数字表法分为4组(n=10),除正常对照组外,其余3组均复制大鼠偏头痛模型。模型对照组只造模,不作其他处理;针刺治疗组造模后进行针刺;针刺预防组针刺后造模电刺激20min。针刺方法:针刺大鼠双侧太冲、阳陵泉穴20min。采用疏密波,电流强度0.3~0.6mA,留针20min,1次/d,共5次。②实验完毕后取脑干及三叉神经节匀浆,采用反转录-聚合酶链反应法测定5-羟色胺1F和诱导型一氧化氮合酶mRNA表达。结果:进入结果分析正常对照组10只,模型对照组、针刺治疗组、针刺预防组各9只,共脱失3只。①与正常对照组比较,模型对照组大鼠诱导型一氧化氮合酶mRNA表达显著增强(P<0.01),5-羟色胺1FmRNA表达显著减弱(P<0.01)。②与模型对照组比较,针刺预防组和针刺治疗组诱导型一氧化氮合酶mRNA表达明显减弱(P<0.01),5-羟色胺1FmRNA表达显著增强(P<0.01)。结论:针刺调控5-羟色胺1F和诱导型一氧化氮合酶mRNA的表达可能是针刺防治偏头痛的分子机制。 相似文献
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Four separate experiments were carried out by dosing dogs (Beagles and Border collies) and red foxes with protoscoleces obtained from hydatid cysts in sheep from mid-Wales. The dogs and foxes were killed at intervals over a period from 34-180 days after infection and the intestines were examined for Echinococcus granulosus. Border collie dogs were efficient hosts in that large numbers of worms developed, with gravid segments present by 55 days after infection; but Beagle dogs were poor hosts in that only small numbers of immature worms developed. Foxes were poor hosts in that few or no worms developed, but gravid segments were seen in three of 29 foxes. The worms showed morphological features similar to the 'sheep' rather than the 'horse' strain. 相似文献
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Retrorenal colon: implications for percutaneous diskectomy 总被引:1,自引:0,他引:1
It has been recommended that computed tomography (CT) with the patient prone be performed in every patient undergoing percutaneous diskectomy; this would enable detection of a retrorenal location of the colon, which could interfere with the percutaneous procedure. In this evaluation of 346 prone CT studies, only one patient (0.29%) was found to have retrorenal or retropsoas bowel that would have been perforated at diskectomy. Because of this extremely low prevalence, the performance of prone CT in every patient undergoing percutaneous lumbar diskectomy is not believed to be necessary. 相似文献
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Neurophysiological investigation of effects of the D-1 agonist SKF 38393 on tonic activity of substantia nigra dopamine neurons 总被引:1,自引:0,他引:1
The effects of the D-1 agonist SKF 38393 on tonic activity of rat substantia nigra pars compacta dopamine neurons were studied using extracellular, single-unit recording techniques. Unlike nonselective D-1/D-2 dopamine agonists or the D-2 agonist quinpirole, SKF 38393 did not inhibit dopamine neuronal activity when applied iontophoretically or when administered intravenously in doses up to 20 mg/kg to chloral hydrate-anesthetized rats. Moreover, pretreatment with SKF 38393 did not alter the inhibitory response of these neurons to apomorphine or the D-2 agonist quinpirole. However, in locally anesthetized, gallamine-treated, artificially respired rats, dopamine cell activity was significantly altered by i.v. administration of SKF 38393; firing rate increases and decreases were observed. Administration of the inactive enantiomer of SKF 38393, S-SKF 38393, did not induce similar changes in parallel experiments. These results support the idea that unlike D-2 autoreceptor stimulation, D-1 receptor stimulation does not exert a direct local effect on dopamine neurons in the substantia nigra pars compacta and suggest that D-1 receptor stimulation at sites postsynaptic to the dopamine cells may indirectly affect the activity of some dopamine neurons through long-loop feedback mechanisms. 相似文献
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Unilateral lesion of the nigrostriatal pathway decreases the firing rate and alters the firing pattern of globus pallidus neurons in the rat 总被引:2,自引:0,他引:2
Activities of spontaneously firing neurons in the globus pallidus of intact rats and rats that survived unilateral lesions of the nigrostriatal pathway for 3 days, 1 week, or 6-11 weeks were compared. No significant differences in neuronal firing rate, firing pattern, and number of cells per pass were observed between chloral hydrate-anesthetized control and lesioned animals. However, in locally anesthetized animals, pallidal cells fired significantly faster than in chloral hydrate-anesthetized animals, and the lesion caused a decrease in the firing rates of pallidal cells 1 week and 6-9 weeks postlesion. In addition, significant differences in the firing pattern of pallidal cells, as determined by the ratio of the mean to median interspike intervals, were seen between locally anesthetized controls and animals surviving 3 days, 1 week, and 6-9 weeks postlesion. This altered firing pattern tended to return to normal with time. The number of cells per pass was not significantly altered by the lesion. Data from this study suggest that, in locally anesthetized animals, the removal of the tonic dopaminergic input to the basal ganglia causes pallidal cells to decrease their firing rates in a time-dependent fashion and causes reversable firing pattern changes. This suggests that tonically active dopamine neurons, probably acting through the striatopallidal pathway, regulate the firing rate and mechanisms controlling the temporal ordering of spontaneous discharges of globus pallidus neurons. 相似文献