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41.
目的研究呼吸纯氧对健康人听感觉门控P50的影响。方法右利手、健康男性大学生志愿者28名,根据随机数字表分为对照组(n=12)和实验组(n=16)。佩戴面罩,对照组呼吸空气,实验组呼吸医用纯氧60 min。应用条件-测试刺激,记录吸氧前(pre0)、吸氧20 min(Oxy20)、吸氧50 min(Oxy50)、吸氧后30 min(post30)的脑电图,计算听觉P50潜伏期和P50感觉门控电位(S1与S2振幅之差)。结果 S1刺激在4个时间点各组P50潜伏期相对稳定(P0.7);吸氧50 min时,实验组比对照组P50潜伏期缩短(P0.05)。S2刺激在4个时间点各组P50潜伏期相对稳定(P0.30),两组间比较无显著性差异(P0.05)。对照组P50门控电位比较稳定(P=0.70),而实验组随吸氧时间逐渐延长,电位越来越高,停止吸氧后,电位迅速回落,Oxy20和post30(P=0.04)、Oxy50和post30(P=0.02)相比均有显著性差异。组间比较,4个时间点均无显著性差异(P0.05)。结论健康人吸60 min纯氧,可能缩短对刺激的反应时间,有增强听觉门控电位的趋势。  相似文献   
42.
4-烷硫基-4-脱氧-4′-去甲表鬼臼毒素的合成和抗肿瘤活性   总被引:6,自引:0,他引:6  
对4’-去甲表鬼臼毒素的C4位进行化学修饰,合成和筛选了10个4-烷硫基-4-脱氧-4’-去甲表鬼臼毒素衍生物以进一步研究C4位不同的原子和取代基与活性之间的关系及寻找结构简单、活性更强的抗肿瘤新药。4’-去甲表鬼臼毒素与硫醇在三氟化硼·乙醚或三氟乙酸存在下生成相应的硫醚,也可用硫醇与4β-溴-4-脱氧-4’-去甲表鬼臼毒素反应生成相应的硫醚。在体外筛选中,化合物10和12抑制L1210白血病细胞的活性与依托泊甙相当或更强,化合物9,10,12和15抑制KB细胞的活性与依托泊甙相当或更强。  相似文献   
43.
Summary The effect of a new formulation of verapamil sustained release (SR) 240 mg tablets on resting blood pressure (BP) and on the pressor response to isometric exertion have been examined in a single-blind, placebo-controlled, cross-over study in 12 hypertensive patients (mean age 45 years).SR verapamil and placebo were administered every 12 h for 6 consecutive weeks. At the end of each period of treatment BP and heart rate (HR) were measured at rest and during isometric exercise, performed as a handgrip (HG) test for 3 min at 30% of the maximum voluntary contraction. There was a significant reduction in resting systolic and diastolic BP, with no change in HR. BP and HR at peak exercise were lower after verapamil than after placebo, but the maximal absolute increase did not change during verapamil therapy.The results are compatible with a role of SR verapamil b.d. in reducing resting BP in hypertension, and in lowering very high pressure at the peak of a HG test, without modifying the physiological reactivity of cardiovascular system.  相似文献   
44.
目的:通过分析精神分裂症患者中枢多巴胺代谢产物-血浆高香草酸浓度(pHVA)与临床指征的关系,进一步探讨多巴胺神经递质及其药物治疗在精神分裂症的作用。方法在46例长期药物治疗、58例未治疗精神分裂症患者中,采用高液相色谱连接电化学分析仪测定PHVA;测前评定阳性症状量表(SAPS)和阴性症状量表(SANS)。结果(1)与62例健康对照组比,治疗组PH-VA显著减低,未治疗组显著增高,以阴性症状组为  相似文献   
45.

INTRODUCTION

The aim of this study was to evaluate temporal trends in the prevalence of primary total hip and knee replacements (THRs and TKRs) throughout the Trent region from 1991 to 2004.

PATIENTS AND METHODS

The Trent Regional Arthroplasty Study records details of primary THR and TKR prospectively and data from the register were examined. Age and gender population data were provided by the Office for National Statistics.

RESULTS

A total of 26,281 THRs and 23,606 TKRs were recorded during this period. Analysis showed that females had an increased incidence rate ratio (IRR) for both primary THR (IRR = 1.29; 95% CI 1.26–1.33; P < 0.001) and TKR (IRR = 1.17; 95% CI 1.14–1.20; P < 0.001). Patients aged 74–85 years had the largest IRR for both primary THR (IRR = 6.7; 95% CI 6.4–7.0; P < 0.001) and TKR (IRR = 15.3; 95% CI 14.4–16.3; P < 0.001).

CONCLUSIONS

The prevalence of primary TKR increased significantly over time whereas THR remained steady in the Trent region between 1991 and 2004.  相似文献   
46.
Perpetuation, overwintering, and extinction of eastern equine encephalitis virus (EEEV) in northern foci are poorly understood. We therefore sought to describe the molecular epidemiology of EEEV in New York State during current and past epizootics. To determine whether EEEV overwinters, is periodically reintroduced, or both, we sequenced the E2 and partial NSP3 coding regions of 42 EEEV isolates from New York State and the Eastern Seaboard of the United States. Our phylogenetic analyses indicated that derived subclades tended to contain southern strains that had been isolated before genetically similar northern strains, suggesting southern to northern migration of EEEV along the Eastern Seaboard. Strong clustering among strains isolated during epizootics in New York from 2003-2005, as well as from 1974-1975, demonstrates that EEEV has overwintered in this focus. This study provides molecular evidence for the introduction of southern EEEV strains to New York, followed by local amplification, perpetuation, and overwintering.  相似文献   
47.
Previous studies have suggested that human follicular fluid contains factors that reduce the zona-binding capacity of spermatozoa. The present study provides further evidence of the existence of such factors. Using the hemizona binding assay (HZA), we have shown that the inhibitory effect of human follicular fluid on the zona-binding capacity of spermatozoa is concentration-dependent, an inhibitory effect being detected when the concentration of human follicular fluid was > or = 10%. A 1% concentration of human follicular fluid did not possess this inhibitory activity. Heating human follicular fluid at 56 degrees C for 30 min did not affect its inhibitory properties; treatment with proteinase-K abolished such inhibition. Human follicular fluid was fractionated sequentially by concanavalin-A affinity chromatography, Mono Q ion-exchange chromatography and Superose-12 gel filtration. The zona binding inhibitory activity resided in the fraction which bound to the lectin and Mono Q column and contained molecules with native molecular weights of 32 and 192 kDa. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis analysis suggested that the 192 kDa glycoprotein was a tetramer, while the 32 kDa glycoprotein remained as a single molecular species under denaturing conditions. We conclude that two glycoproteins were responsible for the zona binding inhibitory activity of human follicular fluid. The physiological role of these factors remains unclear.   相似文献   
48.
血管细胞粘附分子调控造血的研究进展   总被引:1,自引:1,他引:1  
本文简述了血管细胞粘附分子 (Vascularcelladhesionmolecule 1,VCAM 1)的结构和生物学功能 ,总结了VCAM 1在恶性血液病骨髓基质中的表达和意义 ,探讨了VCAM 1在造血干细胞动员和归巢中的作用 ,指出VCAM 1作用机制的深入研究将对恶性血液病的治疗提供更为有效的方法。  相似文献   
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