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81.
This work presents the first sodium MRI functional renal study on a mouse model. The tissue sodium concentration was monitored during induced diuresis with furosemide. By using density-weighted chemical shift imaging (DWCSI) at high field strength a temporal resolution of less than 5 min for three dimensional (3D) data sets with high spatial resolution was achieved. A maximum increase of 20% in the cortex and a decrease of 45% of the original signal strength in the medulla were observed. These findings correspond well with experiments conducted on much larger rodent models. 相似文献
82.
Objective To investigate the prevention of intestines adhesion about sodium hyaluronic acid in postoperative intestines adhesion.Methods Eighteen cases of adhesive intestine obstruction were done intestinal release or bowel resection.2~4mL sodium hyaluronic acid was put to the wound,anastigmatic and rough surface of peritoneal.Gastrointestinal decompression,anti-infective and infusion were taken after oper-ations.Followed up 8~24 months.Results Obstructive symptoms haven't happened,the effective rate is 100%.Only 2 cases have intermittent abdominal pain without obstruction,the incidence was 11%.Conclu-sion Sodium hylauronic acid is effective to prevent the adhesion of postoperative intestines adhesion,simp-ler use,fewer side-effects and great value to appliance. 相似文献
83.
目的:探讨术前急性高容血液稀释联合术中硝普钠控制性降压对腰椎手术病人心率变异性(HRV)的影响.方法:15例腰椎骨折椎板减压、切复内固定病人,术前输入6%羟乙基淀粉20ml/kg和乳酸林格氏液20ml/kg以实施急性高容血液稀释,术中采用硝普钠微泵输注实施控制性降压,输注速度为0.5~6μg·kg-1·min-1,控制平均压(MAP)在55~65mmHg之间.观察插管后稀释前(T0)、稀释后降压前(T1)、降压后10min(T2)、30min(T3)和停降压后10min(T4)和30min(T5)6个时间点总功率谱(TP)、低频值(LF)、高频值(HF)、LF/HF、标化低频值(Lfnrom)和标化高频值(Hfnorm).结果:以上6个时间点TP、LF、HF、LF/HF、Lfnrom和Hfnorm均无显著变化.结论:术前急性高容血液稀释联合术中控制性降压时心脏自主神经功能稳定. 相似文献
84.
Summary Based on the gate-related receptor hypothesis, an analysis of kinetics of AN-132, a new antiarrhythmic agent, blockade of
cardiac sodium channels and the gate-related receptor which is bound by the drug was performed by computer simulation. Model-predicted
apparent rates of onset of AN-132 (30 μmol/L) blocking were 0.051, 0.038, and 0.034 AF−1 at stimulation frequencies of 1.0, 2.0 and 3.0 Hz, respectively. The time constant of recovery from block by AN-132 at resting
potential -90 mV was 39.5 s. These findings are in agreement with those experimental data documented. The analysis of gate-related
receptor shows that AN-132 binds the inactivation gate-related receptor, and the binding and unbinding are modulated by the
inactivation process. 相似文献
85.
The differential effects of the pyrethroid tetramethrin on tetrodotoxin-sensitive (TTX-S) and tetrodotoxin-resistant (TTX-R) single sodium channel currents in rat dorsal root ganglion (DRG) neurons were investigated using the outside-out configuration of patch-clamp technique. Channel conductances were 10.7 and 6.3 pS for TTX-S and TTX-R sodium channels, respectively, at a room temperature of 24–26°C. The single-channel current of TTX-S sodium channels at the test potential of −30 mV was −1.27 ± 0.25 pA, and was not changed after exposure to 10 μM tetramethrin (−1.28 ± 0.23 pA). The open time histogram of TTX-S single-channel currents could be fitted by a single exponential function with a time constant of 1.27 ms. After exposure to 10 μM tetramethrin, the open time histogram could be fitted by the sum of two exponential functions with time constants of 1.36 ms (τfast) and 5.73 ms (τlow). The percentage of contribution of each component to the population was 62% for the fast component representing the normal channels and 38% for the slow component representing the tetramethrin modified channels. The amplitudc of TTX-R single-channel currents was slightly changed from −0.72 ± 0.14 to −0.83 ± 0.07 pA by 10 μM tetramethrin. The open time histogram of TTX-R single-channel currents could be fitted by a single exponential function with a time constant of 1.92 ms. In the presence of 10 μM tetramethrin, the open time histogram could be fitted by the sum of two exponential functions with time constants of 2.07 ms (τfast) and 9.75 ms (τslow). The percentage of contribution of each component was 15% for the fast, unmodified component and 85% for the slow, modified component. Differential effects of tetramethrin on the open time distribution of single sodium channel currents explains the differential sensitivity of TTX-S and TTX-R sodium channels. 相似文献
86.
A. A. Paul A. E. Black J. Evans T. J. Cole R. G. Whitehead 《Journal of human nutrition and dietetics》1988,1(6):437-450
Longitudinal measurements of breastmilk intake in 48 Cambridge infants showed that intake reached a peak of 824 g/24 h in boys and 741 g/24 h in girls in the third and fourth months, respectively. Regression analysis demonstrated that, in the early months, the infants' weight accounted for a major part of the variance in breastmilk intake. Infants in non-manual social classes received more breastmilk and started solids later than those in manual groups. In the early months weight gain showed a relative increase compared to growth standards, but later infancy was characterized by a progressive deceleration in weight and length gain. Adiposity, as measured by triceps skinfold thickness differed most markedly from growth charts and was only equivalent to the tenth standard centile at all ages. The lower skinfold thickness measurements are considered to be more appropriate to breastfed infants in general. 相似文献
87.
Data concerning the food and beverage intake (including alcohol) of 79 males, aged 19–50 years, sleeping rough in Central London, who did not appear to be under the influence of drink, drugs or suffering from mental illness were collected by prompted 24-h recall and food-frequency questionnaire (FFQ). The source of food was noted and the subjects were asked about food availability and food needs. The group had intakes significantly lower than Dietary Reference Values (DRV) for the UK for energy, carbohydrate, non-starch polysaccharides (NSP), folate, zinc and magnesium. Significantly higher values were seen for protein, fat, vitamin B12 , calcium and iron. Alcohol intake was higher than that assumed to approximate current intakes of the UK population. Mean macronutrient intakes for the group were similar to means for British adult men (OPCS, 1990), only protein and NSP were significantly lower. The FFQ showed very low consumption/week of fruit, vegetables, salad, fruit juice and wholewheat/brown products. Organized charities provided the major source of food energy for the group as a whole. Self-supplied sources provided the major source of total energy. It is suggested that the group may benefit from an increase in dietary fibre and energy, with an increase in the proportion of energy supplied by carbohydrate and a reduction in energy from fat and alcohol. A varied supply of food and hot meals during weekends as well as during the week may benefit the group both aesthetically and nutritionally. It may be advisable to increase the supply of wholemeal/brown bread, fruits, vegetables and salad foods without decreasing the energy content of the food available. 相似文献
88.
采用酶动力学及聚丙烯酰胺凝胶电泳方法研究了NaHSO3、NaN3、KSCN、DDC对酪氨酸酶的抑制作用。NaHSO3、NaN3、KSCN为非竞争性抑制作用,随着抑制剂浓度增加,酶活性逐渐减弱。当NaHSO3、NaN3、KSCN的浓度分别达到1.2mmol/L12。5mmol/L12.5mmol/L时,酶活性的抑制率为100%、50%、24%。DDC对酪氨酸酶的抑制作用为竞争性抑制作用,其浓度达4mmol/L时,酶活性100%受到抑制。 相似文献
89.
Sara Townsend Diane Palmer & John MacFie 《Journal of human nutrition and dietetics》1997,10(3):193-195
Seven days or more of inadequate oral intake (IOI) inevitably results in a deterioration in nutritional status. Despite this well-known fact, little information is available as to the frequency with which such periods of IOI occur in clinical practice. This study results from an audit of IOI in a gastroenterological unit over a 6-month period. The results demonstrate that 17% of patients sustained significant periods of IOI of 7 days or longer. This has important implications with regard to the provision of adjuvant nutritional support. 相似文献
90.
高碘摄入对SD大鼠钠/碘同向转运体蛋白表达影响的免疫组化研究 总被引:2,自引:0,他引:2
目的:动态观察长期高碘摄入对SD大鼠甲状腺细胞钠/碘同向转运体(NIS)蛋白表达的影响.方法:SD大鼠分别饲以去离子水及不同碘浓度的碘化钾水,给碘后1 d及1,2,4,8周处死.测定尿碘、组织碘含量,免疫组织化学方法观察甲状腺细胞NIS蛋白表达水平.结果:高碘摄入可引起甲状腺滤泡细胞膜表面NIS蛋白表达的下降.短期较低浓度的高碘摄入对NiS蛋白的表达无明显影响,而较高浓度的碘摄入则引起NIS蛋白表达的明显减少;长期高碘摄入对NIS蛋白表达的抑制作用,可在机体自我调节机制作用下得以部分恢复,但NIS蛋白表达仍处较低水平.结论:高碘摄入可导致甲状腺细胞表面NIS蛋白表达下降,随摄碘浓度的增加抑制作用增强;不同浓度的碘摄入对NIS蛋白表达的抑制作用表达时间不同. 相似文献