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41.
羟丁酸钠对缺血缺氧性脑损伤新生大鼠大脑皮层神经细胞凋亡的影响 总被引:2,自引:1,他引:1
目的 观察羟丁酸钠对缺血缺氧性脑损伤新生大鼠大脑皮层神经细胞凋亡的影响。方法 新生7dSD大鼠随机分为假手术组(S组)、生理盐水对照组(C组)和羟丁酸钠组(71、坦和档组)。每组按Ⅲ(缺血缺氧)后不同时间点进一步分为1h、3h、1d、3d、7d5个亚组(n=6)。按Rice法制作缺血缺氧性脑损伤模型。C、γ1、γ2和γ3组HI后即腹腔分别注射生理盐水0.2ml/10g、羟丁酸钠50、100、200mg/kg,3次/日;S组术后吸空气2h,腹腔注射生理盐水0.2ml/10g,3次/日。TUNEL染色法检测HI后各时间点大脑皮层凋亡神经细胞。结果 HI后1h~7d,C、γ1、γ2、γ3组凋亡神经细胞数高于S组(P〈0.05),且于HI后1d达高峰;HI后3h-3d,C、γ3组凋亡神经细胞数多于γ1、γ2组(P〈0.05),而C组与γ3组之间凋亡神经细胞数差异无统计学意义(P〉0.05);HI后7d,γ1组凋亡神经细胞数多于让组(P〈0.05)。结论 50、100mg/kg羟丁酸钠能抑制缺血缺氧性脑损伤新生大鼠大脑皮层神经细胞凋亡,且100mg/kg效果较好。 相似文献
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本文介绍了20例二尖瓣置换术病人围手术期使用硝普钠的经验。术中和术后早期使用硝普钠可降低肾素-血管紧张素系统的活性、减轻外周血管阻力和后负荷,增强泵血功能,从而使心脏指数升高,降低术后高血压和肺水种的发生率。体外循环停止后,硝普钠与低浓度升压药并用可增强心肌收缩力,预防低排综合征 相似文献
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Angela Ameri 《Naunyn-Schmiedeberg's archives of pharmacology》1997,355(2):273-280
The effects of the Aconitum alkaloid 3-acetylaconitine on neuronal activity were investigated in the slice preparation and on cultivated neurons of rat
hippocampus by extracellular and patch-clamp recordings, respectively. 3-Acetylaconitine (0.01–1 μM) diminished the orthodromic
and antidromic population spike in a concentration-dependent manner. The inhibitory action of the drug was preceded by a transiently
enhanced excitability. The latency of onset of the inhibition was accelerated by increased stimulation frequency, whereas
recovery during washout of the alkaloid was accelerated by decreased stimulation frequency. Moreover, the inhibitory effect
of 3-acetylaconitine was evaluated in two different models of epileptiform activity induced either by blockade of GABA receptors
by bicuculline (10 μM) or by a nominal Mg2+-free bathing medium. In accordance with the activity-dependent mode of action, this compound abolished the synaptically evoked
population spikes in the presence of bicuculline or nominal Mg2+-free bathing medium, respectively. Whole-cell patch-clamp recordings revealed an interaction of 3-acetylaconitine with the
voltage-dependent sodium channel. At a concentration of 1 μM, 3-acetylaconitine did not affect the peak amplitude of the sodium
current, but shifted the current-voltage relationship in the hyperpolarized direction such that sodium currents were already
activated at the resting potential.
Received: 22 July 1996 / Accepted: 14 October 1996 相似文献
46.
I. Sioen † C. Matthys G. De Backer J. Van Camp† & S. De Henauw 《Journal of human nutrition and dietetics》2007,20(6):580-589
BACKGROUND: Regular seafood consumption is recommended in dietary guidelines. The aim of this study was to investigate the importance of seafood as a nutrient source in adolescents' diet and the extent to which seafood consumption can increase the intake of omega-3 polyunsaturated fatty acids and vitamin D. METHODS: Consumption data recorded during seven consecutive days for 341 adolescents selected in Ghent (Belgium) were used to estimate the intake of vitamin D, linoleic (LA), alpha-linolenic (LNA), arachidonic (AA), eicosapentaenoic (EPA), docosapentaenoic (DPA) and docosahexaenoic (DHA) acid. RESULTS: The adolescents consumed on average 3.21 microg/day vitamin D, 11.7 g/day LA and 1.4 g/day LNA. The mean intakes of AA, EPA, DPA and DHA were 83.2, 55.9, 18.4 and 111.4 mg/day respectively. The major source of vitamin D was fortified margarine. Fats and oils were the main sources for LA and LNA. The intake of AA was mainly contributed by meat, poultry and eggs. Fish and seafood contributed for 84.1%, 59.3% and 64.4% respectively for EPA, DPA and DHA. CONCLUSION: Flemish adolescents would benefit from increased seafood consumption, as this would lead to a higher intake of EPA and DHA as well as of vitamin D. Moreover, replacement of foods rich in saturated fat (SFA) by seafood products can help to reduce SFA intake. 相似文献
47.
High-protein Weight-loss Diets: Are They Safe and Do They Work? A Review of the Experimental and Epidemiologic Data 总被引:6,自引:0,他引:6
Julie Eisenstein M.D. Susan B. Roberts Ph.D. Gerard Dallal Ph.D. Edward Saltzman M.D. 《Nutrition reviews》2002,60(7):189-200
Recommendations for increased consumption of protein are among the most common approaches of popular or fad diets. This review summarizes the effects of dietary protein on satiety, energy intake, thermogenesis, and weight loss, as well as its effect on a variety of health outcomes in adults. In short-term studies, dietary protein modulates energy intake via the sensation of satiety and increases total energy expenditure by increasing the thermic effect of feeding. Whereas these effects did not contribute to weight and fat loss in those studies in which energy intake was fixed, one ad libitum study does suggest that a high-protein diet results in a greater decrease in energy intake, and therefore greater weight and fat loss. In terms of safety, there is little long-term information on the health effects of high-protein diets. From the available data, however, it is evident that the consumption of protein greater than two to three times the U.S. Recommended Daily Allowance contributes to urinary calcium loss and may, in the long term, predispose to bone loss. Caution with these diets is recommended in those individuals who may be predisposed to nephrolithiasis or kidney disease, and particularly in those with diabetes mellitus. 相似文献
48.
S. Y. Wong E. M. Lau W. W. Lau† & H. S. Lynn 《Journal of human nutrition and dietetics》2004,17(4):359-364
To determine the feasibility of increasing the calcium, protein and calorie intake of osteoporotic fracture patients by repeated dietary counselling delivered by a dietitian, a randomized controlled trial was conducted. Among 189 patients presenting with osteoporotic fractures to an Orthopaedics and Traumatology Department of a large regional hospital, 98 patients were randomized to the intervention group and 91 were randomized to the control group (with usual care). Intervention group received three sessions of dietary counselling with tailored made recommendations over a period of 4 months, while the control group only received dietary assessment and pamphlets on the prevention of osteoporosis. Almost all subjects in both intervention and control groups had calcium intake below the recommended level of 1000 mg at baseline. Half and 60% of subjects in both groups had total energy and protein intake below recommended levels respectively. The mean weights of control and intervention groups at baseline were 51.5 and 50.9 kg respectively, while the body mass index (BMI) were 22.6 (kg m(-2)) and 22.6 (kg m(-2)) respectively. After dietary intervention, significant increase of intake was seen in calcium intake (P = 0.0095 by t-test) in the intervention group. No significant increase was seen in protein or calorie intake. No significant change was observed in the body weight or BMI although there was a positive trend in the intervention group for all these parameters. We concluded that there was general malnutrition in Chinese elderly who presented with osteoporotic fractures. Dietary calcium could be increased by repeated professional dietary counselling. Future studies with longer duration and more objective clinical outcomes will be helpful to further demonstrate the long-term effects of dietary intervention on osteoporosis and other chronic diseases. 相似文献
49.
贵州小型香猪麻醉方法的比较研究 总被引:6,自引:2,他引:4
目的 探索快速安全地麻醉贵州小型香猪的方法。方法 90头贵州小型香猪随机分为肌内注射组、腹腔注射组、静脉注射组 ,比较用 3%戊巴比妥钠溶液麻醉的显效时间、麻醉效果及死亡率。结果 肌内注射显效时间 (15± 5 )min ,麻醉效果优 80 %、良 16 7%、死亡 3 3% ;腹腔注射显效时间 (13± 4 )min ,麻醉效果优 6 0 %、良2 0 %、差 16 7%、死亡 3 3% ;静脉注射显效时间 (10± 2 )min ,麻醉效果优 73 3%、良 16 7%、死亡 10 % ;结论 肌内注射麻醉是一种安全可靠的麻醉方法。 相似文献
50.
为获得我食品和膳食中放放射性核素含量并为制定?食品中放射性物质限制浓度标准?提供依据,在1982~1086年问由30个辐射防护单位协作,测定了我过14类(27种)特定食品种22种放射性核素浓度.按我国三种主要膳食食类型.从14个正常本底辐射的省或自治区及三个非正常地区采集样品进行分析测定.估算了这些地区居氏15种放射往核素的年摄人最及所致待积剂量毒量.我国正常本底辐射地区成年男子对这15种核索年总摄入量约为4.2×104Bq,所致总待积剂量当量约为0.43×104Sv.在两个天然放射性较高地区天然放射性核素的年摄入量和所致待积剂量当量比正常本底辐射地区高得多,而在该核工厂周围地区采集的食未明显放射性污染.文章还讨论了各类食品或放射性核素对总待积剂量当量的相对贡献. 相似文献