Phylogenetic, ontogenetic, and pathological aspects of the urine-concentrating mechanism

The urine-concentrating mechanism is one of the most fundamental functions of avian and mammalian kidneys. This particular function of the kidneys developed as a system to accumulate NaCl in birds and as a system to accumulate NaCl and urea in mammals. Based on phylogenetic evidence, the mammalian urine-concentrating mechanism may have evolved as a modification of the renal medulla's NaCl accumulating system that is observed in birds. This qualitative conversion of the urine-concentrating mechanism in the mammalian inner medulla of the kidneys may occur during the neonatal period. Human kidneys have several suboptimal features caused by the neonatal conversion of the urine-concentrating mechanism. The urine-concentrating mechanism is composed of various functional molecules, including water channels, solute transporters, and vasopressin receptors. Abnormalities in water channels aquaporin (AQP)1 and AQP2, as well as in the vasopressin receptor V2R, are known to cause nephrogenic diabetes insipidus. An analysis of the pathological mechanism involved in nephrogenic diabetes insipidus suggests that molecular chaperones may improve the intracellular trafficking of AQP2 and V2R, and, in the near future, such chaperones may become a new clinical tool for treating nephrogenic diabetes insipidus.     

Relationship between short-circuit current and unidirectional fluxes of Na and Cl across the ciliary epithelium of the toad: demonstration of active Cl transport.

The unidirectional fluxes of Na⁺ and Cl^? across the isolated toad ciliary epithelium were measured under short-circuit conditions. In a normal medium, the transepithelial potential difference was about 4 mV, the epithelial side being negative with respect to the stroma side. The short-circuit current (SCC) was 46 μA/cm² and the average electrical conductance was 11 mmhos/cm². Both the Na⁺ and Cl^? fluxes from the stromal to epithelial side were greater than those in the opposite direction and the net Cl^? flux was 4 to 5 times greater than the net Na⁺ flux. In the stromal tirection, both the Na⁺ and Cl^? fluxes were linearly related to the SCC, and the sum of the partial ionic conductances of Na⁺ and Cl^? exceeded the electrical conductance. No correlation between the SCC and the Cl^? or Na⁺ flux was found in the opposite direction and the sum of the partial ionic conductance agreed well with the electrical conductance. In the presence of either theophylline in 10 mm or ouabain in 1 mm, the SCC was decreased by about 70% and unidirectional fluxes of either direction were increased in accordance with the increase in the electrical conductance, except for the stromal to epithelial Cl^? and Na⁺ fluxes in the presence of theophylline and ouabain, respectively. The data indicate that electrogenic Cl^? transport is the major function and the major source of the SCC in the epithelium.     

WATER AND ELECTROLYTES IN MALNUTRITION

Dermal and urinary losses of electrolytes are important therapeutic considerations in the rehabilitation of the malnourished child. A simple formula based on the use of cow's milk is suggested for the treatment of these children.     

恒康正清在经直肠前列腺穿刺活检术前肠道准备中的应用

目的探讨前列腺穿刺活检术前采用口服恒康正清作肠道准备的效果。方法选择我科2006年9月~2008年12月行前列腺穿刺活检的患者42例,随机分为观察组和对照组,各21例。对照组采用肥皂水清洁灌肠,观察组采用口服恒康正清。并观察肠道清洁过程中不良反应及穿刺术后血白细胞计数、尿白细胞计数、体温变化。结果观察组不良反应明显低于对照组(P<0.01,P<0.05)。两组术后白细胞计数、尿白细胞计数、体温的比较无显著性差异(P>0.05)。结论口服恒康正清可以代替传统的肥皂水清洁灌肠作为前列腺穿刺活检术前的肠道准备。     

复方聚乙二醇电解质散在妇科手术病人术前肠道准备中的应用

[目的]观察复方聚乙二醇电解质散在妇科手术病人术前肠道准备中的应用效果,探讨其护理措施。[方法]将150例妇科择期手术病人随机分为两组,观察组78例应用复方聚乙二醇电解质散进行术前肠道清洁准备,对照组72例口服硫酸镁及常规灌肠。比较两组病人肠道清洁度、肠道清洁过程中不良反应发生情况。[结果]观察组病人肠道清洁度优于对照组(P<0.05);观察组病人肠道清洁过程中发生不良反应为8.9 7%,对照组为19.44%,观察组明显少于对照组(P<0.05)。[结论]复方聚乙二醇电解质散用于妇科手术病人术前肠道清洁效果优于口服硫酸镁及常规灌肠,且不良反应少。     

Asymmetric capacitance response from the chemical characteristics of activated carbons in KOH electrolyte

The positive and negative capacitance behaviors of heat-treated activated carbons are separately studied in a three-electrode configuration using 6 M KOH and 1 M H₂SO₄ as electrolytes. Heat treatment of activated carbons at 400–800 °C causes slight changes in surface area accompanied by a significant removal of oxygen-containing functional groups. Consequently, the specific surface capacitance with a 25% reduction in the negative and an 8% reduction in the positive are monitored in KOH electrolyte. The unequal capacitance reductions as well as the asymmetric CV curves reveal that the negative pseudo-capacitances are much larger than the positive ones in KOH electrolyte. These results could be ascribed to the redox reactions preferring in the negative region. The insertion process of cation also plays a significant effect on the asymmetric capacitance behavior. Compared with the identical electrochemical response in H₂SO₄ electrolyte, huge difference in the capacitance values of both electrodes in KOH electrolyte will give a less contribution to the cell capacitance. To optimize the cell performance, a suitably increasing the weigh of active materials in the positive, especially for activated carbon with high level of oxygen-containing functional groups, is recommended.     

不同肠道准备方法对腹腔镜结直肠癌手术效果的影响

目的 观察不同肠道准备方法对腹腔镜结直肠癌手术效果的影响.方法 将61例接受腹腔镜结直肠癌手术患者随机分为观察组32例与对照组29例.观察组术前肠道准备给予口服复方聚乙二醇电解质散,对照组术前肠道准备给予口服甘露醇,对比两组患者回肠末端至直肠上段的肠管直径、肠道清洁程度等指标.结果 复方聚乙二醇电解质散组患者回肠末端至直肠上段的肠管直径均明显小于甘露醇组,差异有非常显著性意义(P＜0.01);肠道清洁程度两组对比无差异(P＞0.05).结论 对于腹腔镜结直肠癌手术患者,用复方聚乙二醇电解质散作为术前肠道准备优于使用甘露醇,它使患者肠内积气减少,便于术野的暴露,有利于手术的顺利进行,减少并发症的发生,能更快促进患者术后恢复.     

A Critical Review for an Accurate Electrochemical Stability Window Measurement of Solid Polymer and Composite Electrolytes

All-solid-state lithium batteries (ASSLB) are very promising for the future development of next generation lithium battery systems due to their increased energy density and improved safety. ASSLB employing Solid Polymer Electrolytes (SPE) and Solid Composite Electrolytes (SCE) in particular have attracted significant attention. Among the several expected requirements for a battery system (high ionic conductivity, safety, mechanical stability), increasing the energy density and the cycle life relies on the electrochemical stability window of the SPE or SCE. Most published works target the importance of ionic conductivity (undoubtedly a crucial parameter) and often identify the Electrochemical Stability Window (ESW) of the electrolyte as a secondary parameter. In this review, we first present a summary of recent publications on SPE and SCE with a particular focus on the analysis of their electrochemical stability. The goal of the second part is to propose a review of optimized and improved electrochemical methods, leading to a better understanding and a better evaluation of the ESW of the SPE and the SCE which is, once again, a critical parameter for high stability and high performance ASSLB applications.     

复方聚乙二醇电解质散联合甘油灌肠剂用于妇科恶性肿瘤肠道准备临床观察

目的：观察复方聚乙二醇电解质散联合甘油灌肠剂在妇科恶性肿瘤术前肠道准备中的临床效果。方法32例接受妇科恶性肿瘤手术的患者,于手术前口服复方聚乙二醇电解质散溶液,联合甘油灌肠剂灌肠,观察患者不良反应、肠管状况、术后肛门排气时间评估肠道准备效果。结果复方聚乙二醇电解质散联合甘油灌肠剂用于妇科恶性肿瘤术前肠道准备具有好的临床效果,且副反应少。结论复方聚乙二醇电解质散联合甘油灌肠剂用于妇科恶性肿瘤术前肠道准备,方法简单,安全,有效,患者痛苦小。