Infrared-spectrometric determination of D2O in biological fluids

The determination of D₂O in biological fluids by means of infrared spectrometry was reinvestigated. When the temperature of a solution, containing D₂O in the range from natural abundance to 5 ml·1^–1 increases, its absorbance decreases and the wavenumber of maximum absorption shifts to a higher value. Both changes are linearly related to the change in temperature. Storage for 17 d in either glass or polyethylene tubes does not affect the D₂O concentration. Purification of biological fluids by vacuum-sublimation removes all substances which also absorb at the O-D vibration band and the recovery of D₂O from plasma and urine is complete. The partition ratio of D₂O between plasma water and red cell water equals unity, and the same holds for plasma water and urine water over a wide range of urine flows and osmolalities. The arterial and urinary disappearance curves of D₂O, measured over several days, both permit the calculation of the total amount of body water (V ^bw), the daily water turn-over (F) and the half-time of water in the body (t _1/2), but the data derived from arterial disappearance curves are more precise. In 16 male mongrel dogs (25–32 kg body mass) the following results were obtained:V ^bw=626±28 ml·kg^–1,F=12.0±3.2% andt _1/2=6.21±1.78 d.     

Effects of sympathetic inhibition on blood pressure and renal responses to central hypervolaemia in normal humans

The purpose of this study was to evaluate the effects of short-term sympathetic inhibition with clonidine on blood pressure and renal responses to central hypervolaemia induced by thermoneutral head-out water immersion. Eleven healthy subjects were randomly studied on two occasions, during a 1 h pre-immersion period, 2 h of water immersion and a 1 h post-immersion period, after either placebo or clonidine treatment. Clonidine caused a significant suppression of plasma adrenaline, plasma noradrenaline, urinary noradrenaline excretion and mean arterial blood pressure. Blood pressure remained constant during water immersion after both placebo and clonidine, compared with the respective pre-immersion control values. The suppression pattern of plasma catecholamines and urinary noradrenaline in response to water immersion during placebo was similar after clonidine treatment. Renal volume excretion was not affected by clonidine. In contrast, clonidine caused a significant attenuation of the immersion-induced stimulation of natriuresis (maximum -33±12%, P<0.01, compared with placebo). These data indicate that the renal capacity to excrete sodium is impaired during moderate blood pressure reduction by short-term sympathetic inhibition with clonidine, whereas the regulation of arterial blood pressure in response to central hypervolaemia is maintained.     

Effect of early outdoor experience on the activity of wild and semi-domestic deermice

The gross activity of wild and semi-domestic strains of prairie deermice was measured in two kinds of novel test apparatus (tilt-cage and activity wheel). Differences in strain activity were not obtained in either apparatus. Activity was significantly decreased in both strains by early experience in the field and by rearing wild genotype subjects in large laboratory cages. It was suggested that differential early sensory experience associated with both qualitative and quantitative aspects of the early rearing environment may be responsible for the treatment effect. Whereas no daily changes in activity were noted in the tilt-cages, activity in the wheels was sipnificantly higher on day 1 for all groups. In contrast to recent literature, wheel running activity did not change with total water deprivation.     

Environmental risk factors for hepatitis A infection in the Zenica–Doboj Canton, Bosnia and Herzegovina

In the Zenica-Doboj Canton, 1106 hepatitis A virus (HAV) infections were reported during 2000 (an incidence rate of 252/100 000 population), with 996 (90.1%) cases occurring in nine community-wide outbreaks. Analysis of water supplies showed that 398 (19.1%) samples contained coliforms, including 202 (50.8%) that were contaminated with thermotolerant Escherichia coli. Sewage sanitation systems were absent or substandard in 53 910 (81.8%) rural households. The group most affected during outbreaks comprised children aged 7-14 years (incidence rate of 598/100 000). The development of health promotion and prevention initiatives in schools, combined with rigorous hygiene measures, will be necessary to achieve control of the spread of HAV.     

Postoperative water and electrolyte changes in skeletal muscle: a clinical study with three different intravenous infusions

Twenty-seven patients admitted for cholecystectomy were matched for age and sex in three groups for different perioperative fluid therapies over a period of 3 days. Group I was given an acetated half-isotone "balanced" saline solution with the addition of 2.5% glucose, Group II an acetated Ringer solution and Group III an isotonic glucose solution. Percutaneous muscle biopsies were performed before and on the third day after surgery for the determination of water content and the concentration of sodium, potassium, magnesium and chloride in skeletal muscle. The cumulative balance of sodium and potassium was measured daily during the study. In all three groups a significant increase in the total muscle water content was demonstrated. The concentration of sodium and chloride in skeletal muscle increased significantly in Groups II and III, whereas the concentration of potassium decreased in all groups. The cumulative sodium balance was positive in Groups I and II; the potassium balance was negative in all groups. In conclusion, the patients given the balanced saline solution showed the least change in water content and electrolyte concentrations in skeletal muscle.     

磁处理水对抗癌药物的解毒作用

我们的实验发现，磁处理水对环磷酰胺等五种抗癌药物的毒性具有不同程度的缓解作用，能增加小鼠的存活率，能降低药物引起的白细胞减少。对目前癌化疗中使用率最高的环磷酰胺，其作用最明显。     

Effect of Locus Coeruleus Stimulation on Ocular Hypertension and Pathology of Pulmonary Surfactant during Chronic Emotional Stress

In chronic experiments on rabbits and rats, parameters of eye homeostasis (intraocular pressure and ocular hydrodynamics) and lungs (water balance and surface-active properties of surfactant) were studied during electrical stimulation of the locus coeruleus against the background of chronic stress induced in rabbits by repeated electrical stimulation of the ventromedial nucleus and in rats by daily immobilization on a platform. Stimulation of the locus coeruleus eliminated ocular hypertension of hypothalamic origin and stress-induced disturbances in surface activity, blood volume, and water balance in the lungs.     

UV-Cured PDMS for Oil Removal from Wastewater

The removal of oil from water is a worldwide challenge that must be faced to avoid irreversible marine habitat destruction. A novel fast and simple technique to obtain polydimethylsiloxane (PDMS) membranes is developed using the photopolymerization technique. The high reactivity of the acrylated PDMS formulation toward photo-induced free radical polymerization is assessed via the differential scanning photo-calorimetry (photo-DSC) technique. Two different membranes dense or porous are developed and investigated. Porous membranes, having 100–200 µm as pore size, are obtained using a low-cost environmentally friendly sodium chloride template. Thanks to the hydrophobic/oleophilic intrinsic characteristic of PDMS, the UV-cured membranes can selectively remove dodecane, selected as the target oil, from water. The dodecane sorption capability of both membranes is investigated and compared. Moreover, the membranes can be easily reused since the adsorbed oil can be recovered by simply compressing the membrane. Those PDMS sorbents show high mechanical stability after five adsorption/desorption cycles.     

自动变温热交换水箱的研制

通过对变温热交换水箱的智能化设计（硬件和软件）,实现了循环水温的自动化控制,从而达到对热交换水箱中逆向运动的血液温度按临床需要自动进行温度调节。     

碱离子水饮用后血小板聚集率的的变化(附30例报告)

目的:报告30例饮用豪斯牌碱离子水前、后血小板聚集率的变化。方法:饮用碱离子水前、后(2～3月,>3～6月)作比浊法血小板聚集试验,以1分钟、5分钟及5分钟内最大聚集率(Max％)为指标,同时检测部分血粘度指标及凝血因子,并用自动生化仪检测血糖、血脂、主要电解质及部分肝、肾功能。结果:饮碱离子水后,血小板聚集率明显下降,而以疾病组(Max>80％)下降尤为明显,P均<0.001。饮碱离子水后血小板聚集率的下降,部分可能与损伤的血管内皮得到修复有关。主要电解质及部分肝、肾功能无明显异常改变。结论:由于心、脑血管血栓性疾病患者血小板聚集率多明显升高,饮碱离子水后血小板聚集率明显下降,且长期饮用对主要电解质及部分肝、肾功能无明显异常改变,作者认为碱离子水使用方例、安全、有效、价廉,因而对心、脑血管血栓性疾病防治方面可能是一种积极的辅助方法,值得临床进一步探索。