THE CHLORIDE-WATER BALANCE SHEET—An Aid in the Management of Difficult Fluid Balance Problems

In cases in which there is massive loss of fluids or electrolytes or prolonged decreased urinary output, an absolutely accurate knowledge of all water and chloride intake and output by all routes is necessary to avert large and often fatal errors in water and electrolyte therapy based on estimates made from nurses'' notes alone.By use of the Scribner water-chloride balance sheet method of recording data, it is possible to determine with the necessary accuracy how much fluid and what kind of electrolytes to administer to achieve and maintain balance. The method is simple and can be put into effect in any hospital with the cooperation of an educated nursing and laboratory staff.     

CONSIDERATIONS OF POSTOPERATIVE ELECTROLYTE AND FLUID REPLACEMENT

The most important postoperative fluid considerations are maintenance of adequate urinary output, of blood volume, and of extracellular and interstitial cell water and electrolytes.Normal urinary output is between 1,000 and 1,500 cc. daily. A fluid intake of 2,000 cc. of 5 per cent dextrose in distilled water, plus 500 cc. of normal saline solution, will insure this amount of urinary output.The use of 5 per cent dextrose solutions in distilled water provides fluid, retards the protein catabolism of the body, and spares electrolytes.Irradiated plasma is the only intravenous solution which will adequately supply protein in amounts to maintain nitrogen equilibrium. Protein hydrolysates in the absence of adequate caloric intake do not provide enough protein for nitrogen balance.The role of the potassium ion is ordinarily not a consideration in postoperative fluid management. It becomes a consideration in the presence of a large amount of drainage from wounds or abscess cavities, nasogastric suction, or intestinal fistulae. It also must be given attention in cases in which parenteral administration of fluids is necessary for a prolonged period.     

Plant water balance with tritiated water-tracing dynamical method

The conception of "metabolic pool" is introduced and an ecosystem model consisting of sand body metabolic pool, plant metabolic pool, atmospheric pool and their corresponding channels is established. In addition, the input and output terms of water balance including plant transpiration etc. are measured by tritiated water-tracing dynamical method, etc. and thus a water balance table is obtained. Finally, the plant water balance in the steppified desert environment of the Shapotou area at southeastern fringe of Tengger Desert in China is comprehensively analysed.     

A recording plant transpiration balance

Transpiration rates, automatically monitored, provide a basis for investigating factors that affect the movement of water through plants and are particularly useful for demonstrating the role of leaf stoma. A transpiration balance is described which permits monitoring of transpiration rates by continuously recording the weight loss from a potted plant. It is based on the use of a displacement transducer to obtain a signal voltage output from an ordinary mechanical balance. Since it mainly incorporates equipment common to most laboratories, construction of the balance may involve relatively little expenditure. Experiments using the transpiration balance are presented and discussed.     

The effect of barbiturates on 24-h water intake and renal excretion of sodium and water in dogs

The effects of barbiturates on 24-h intakes of water and food and urinary excretion of sodium and potassium as well as on plasma concentration of sodium and potassium and osmolality were examined in dogs placed in metabolism cages and fed with a semiliquid diet. Administration of barbiturates stimulated drinking in a Series of 8 dogs having free access to water. Twenty four-h water intake and water balance increased significantly. Food intake, urinary output and urinary excretion of solutes, sodium and water did not change in this Series. A significant decrease in urine output as well as in osmolal clearance and urinary excretion of sodium was observed in a Series of 7 dogs having water restricted for 24 h following administration of barbiturates. Water balance increased in this Series. The same restriction of water in the dogs which had not received barbiturates did not modify renal excretion of water and electrolytes. Plasma osmolality, sodium and potassium concentrations did not change in either Series of experiments. It is concluded that barbiturates induce positive water balance either by stimulation of drinking when water is freely available or by reduction in urine output when water is restricted. The results suggest that expansion of the body fluids following the increased water intake may abolish reduction in urine output and sodium excretion which otherwise occur after administration of barbiturates.     

The water-electrolyte balance in rats with acute overheating and forced rehydration]

The animals were overheated in thermal chamber for the period of 4 hours at 37 degrees C. Though the water intake was not limited, the rats developed the state of dehydration accompanied by weight loss, redistribution of water and electrolytes in tissues and decrease of circulation plasma volume. Intragastric probe water administration in the quantity equal to the weight loss led to partial rehabilitation of the initial indexes, however full rehabilitation of water-electrolyte balance was observed while administering hypotonic salt solution. The conclusion is made that in case of water rehydration a disorder of water-salt exchange of kidney mechanisms regulation is observed and it is advisable to use hypotonic salt solutions to achieve quick rehydration effect.     

草地农业生态系统的碳平衡分析方法

根据草地农业生态系统的结构,它的碳平衡为4个生产层的碳平衡之和,也是3个界面的碳平衡之和,而某一生产层或者某一界面的碳平衡则是其固定、输入、排放和输出的碳之和。草地农业生态系统4个生产层的碳平衡分析方法定量重要生产环节的碳汇与碳源过程,便于草业生产改进碳汇管理;草地农业生态系统3个界面的碳平衡分析方法显示碳源和碳汇的发生机理,及其空间和数量关系,便于调控草业生产组分以增汇减排;但是,这两个方法不易区分碳的来源和去向,难以明确其利用效率。草地农业生态系统碳平衡分析的输入/输出法定量地指示碳的来源和去向,以及碳效率,计算简单,但是较为概括,不利于牧场尺度的草业碳汇管理。以中国祁连山甘肃马鹿牧场和澳大利亚塔斯玛尼亚奶牛牧场为例,用3种方法分析了两个牧场的碳平衡,结果表明,放牧管理的草业系统的主要碳源是休闲旅游、产品加工流通环节产生的温室气体,主要碳汇是草地和土壤中贮存的碳,好的草地管理可以增汇减排。     

Regulation of renal and lower gastrointestinal function: role in fluid and electrolyte balance

For the majority of vertebrates, the kidneys are not the sole organs that function to maintain homeostasis of body fluid and electrolytes. Mammals are unusual in this respect, as the kidneys are the organs that fill this role. For non-mammalian vertebrates, other organs such as gills, skin, salt glands, urinary bladders and the gastrointestinal (GI) system function in concert with the kidneys in the control of fluid and ion balance. Birds are of particular interest and unique as they do not possess a urinary bladder and the renal output enters the lower GI tract. The physiology of the interaction of avian kidneys and lower GI tract is an excellent example of integrative physiology and several aspects of it have been examined, for example, the role of the avian antidiuretic hormone (arginine vasotocin, AVT) in controlling renal output. AVT produces both a tubular and glomerular antidiuresis. The glomerular antidiuresis is important, as the fluid from the kidneys that enters the GI should not be highly concentrated. Another hormone, aldosterone, has been shown to play an important role in regulating the transport of sodium by the GI epithelium. In addition, the lower GI tract plays a significant role in recycling a portion of the nitrogen that leaves the kidneys as uric acid. Furthermore, the output of avian kidneys contains large amount of protein that is conserved by the lower GI tract.     

Effects of acid water exposure on plasma cortisol, ion balance, and immune functions in the "cobalt" variant of rainbow trout

This study was undertaken to examine physiological responses to acidification of environmental water in the "cobalt" variant of rainbow trout (Oncorhynchus mykiss), which exhibits malformation of the pituitary, by following changes in plasma levels of cortisol and electrolytes, blood pH, gill Na(+), K(+)-ATPase activity, and immune functions after exposure to acid water (pH 4.5). Resting levels of plasma cortisol and lysozyme were significantly lower in the cobalt variant than in the normal trout, whereas plasma ceruloplasmin was significantly higher in the cobalt variant, suggesting that some endocrine factors, lacking or deficient in the cobalt variant, are important for the regulation of its immune functions. Blood pH was slightly but significantly lower in the cobalt variant at rest. After exposure to acid water for 24 h, both the normal trout and cobalt variant showed a significant elevation in plasma cortisol, although the increased level in the cobalt variant was still lower than that in the normal trout transferred to neutral water. No differences were seen in blood pH, plasma electrolytes, and gill Na(+), K(+)-ATPase activity between the normal trout and the cobalt variant, indicating that the cobalt variant regulates ion balance when exposed to acid water, despite malformation of the pituitary. Although the normal trout showed a reduction in plasma lysozyme level after acid exposure, there was no significant change in the cobalt trout. Adverse effects of pituitary malformation on ion balance and immune functions may be compensated by extrapituitary factors in the cobalt variant when it is exposed to acid water.     

Renal effects of the acute inhibition of angiotensin-converting enzyme. I. 1) Studies during normal sodium and potassium balance]

We have investigated the effective role of angiotensin II on the renal function and urinary excretion of some prostanoids in healthy women submitted to different conditions of potassium balance. To this aim we have evaluated the effects of an acute inhibition of angiotensin converting enzyme by enalapril (E). The renal function was explored by clearance (cl.) method during induced hypotonic polyuria (oral water load followed by 5% dextrose solution infusion). During 60 min cl. period the urinary PGE2, 6-keto-PGF1 alpha and TxB2 were determined by RIA method. Each subject received paired studies, in absence and presence of E (10 mg administered per os 1 hour before the water load). Basal values of plasma renin activity (PRA) and urinary aldosterone (excreted during the 24 hours before the water load) were also determined by RIA method. This study protocol was applied in normal potassium balance (n = 6) and induced moderate potassium depletion (n = 6). This paper concerns the group in normal potassium balance in both absence (N3) and presence of E (N3.E). All subjects were submitted to normal dietary intake of sodium (150 mmol/d) and potassium (50 mmol/d). The basal values of PRA, urinary aldosterone and plasma electrolytes were in the normal range. The only significant effect produced by E was a reduction in mean arterial pressure, without significant changes in creatinine cl., urinary hydro-electrolyte excretions as well as urinary excretions of prostanoids.(ABSTRACT TRUNCATED AT 250 WORDS)     

Intestinal anion exchange in teleost water balance

Simultaneous measurements of all major electrolytes including HCO3(-) and H+ as well as water demonstrated that fluids absorbed by the anterior intestine of the marine gulf toadfish under in vivo-like conditions on an overall net basis are hypertonic at 380 mOsm and acidic ([H+] = 27 mM). This unusual composition of fluids absorbed across the intestinal epithelium is due to the unusual intestinal fluid chemistry resulting from seawater ingestion and selective ion and water absorption along the gastro-intestinal tract. Measurement under near symmetrical conditions with high NaCl concentrations and low MgSO4 concentrations revealed absorption of iso-osmotic and much less acidic fluids by the intestinal epithelium, a situation resembling that of other water absorbing leaky vertebrate epithelia. Reduced luminal NaCl concentrations seen in vivo results in lower absolute water absorption rates but higher Cl-/HCO3(-) exchange rates which are associated with higher net H+ absorption rates. It appears that apical anion exchange is important for net Cl- uptake by the marine teleost intestine especially when luminal NaCl concentrations are low and/or when MgSO4 concentrations are high. Observations indicate that fluid absorption from solutions of low NaCl but high MgSO4 concentrations is energetically more demanding than absorption from NaCl rich solutions at the level of the intestinal epithelium. Furthermore, the high luminal MgSO4 concentration which is an unavoidable consequence of seawater ingestion projects a demand for renal and branchial compensation for intestinal MgSO4 uptake and absorption of hypertonic and acidic fluid by the intestine.     

Water balance in rats exposed to chronic centrifugation.

Changes in gravitational load have been shown to alter renal function, which could potentially affect water balance. Therefore, the present study was conducted to determine the effects of chronic centrifugation on water balance. Eight Sprague-Dawley rats were centrifuged (12 days at 2 G), and eight rats were used as a control group. Water balance over the course of the study was determined by quantifying the percentage (%) of total body water [TBW; (TBW/body mass)] and water flux (water consumption - urine volume). TBW was estimated, by means of deuterium oxide dilution, before the study and after 3 days of centrifugation and by means of desiccation after 12 days of centrifugation. %TBW did not change in the centrifuged rats from initial levels or relative to controls over the course of the study. Differences between the sum of water consumption and sum of urine volume for the 12-day period were the same in both groups. Although an initial period of negative water balance was observed, the lack of a change in %TBW among the three measurement periods or in water flux over the 12 days of centrifugation suggests that water balance is not negatively affected as a result of centrifugation at 2 G.     

Water balance and osmoregulation in a free-ranging tenebrionid beetle, Onymacris unguicularis, of the Namib Desert

Onymacris unguicularis, a fog-basking tenebrionid beetle of the Namib Desert, has mean water influx rates of 49.9 mg H₂O/g.d and mean efflux rates of 41.3 mg H₂O/g.d with mean mass gain being 10.7 mg/g.d. If only steady-state conditions are considered (no mass change), and passive vapour input subtracted, drinking accounts for 50% of water input. Active beetles must drink in order to maintain water balance, while inactive beetles can maintain water balance either eating seeds or by simply metabolizing fat. Little change is observed in ratios of haemolymph and total body water to dry mass when fogs occur, while significant changes in haemolymph osmotic pressure are associated with fog occurrence.For short periods, O. unguicularis can tolerate dehydration with only slight changes in the ratio of total body water and haemolymph to dry body mass and to haemolymph osmotic pressure. For longer periods however, active beetles must have access to fog water for water balance maintenance. This is probably necessary for reproduction.     

Effects of age on water balance in Drosophila species.

Age-related declines in physiological performance have been documented in a wide variety of organisms. However, it is unknown whether related species age in a similar manner or whether physiological differences associated with aging differ widely among species. Previous work has shown that the desiccation resistance of Drosophila melanogaster decreases rapidly with age. Other Drosophila species may have delayed reproductive maturity or may inhabit arid habitats, so that age-related changes in water balance may be a significant physiological constraint on their ecological success. We may, therefore, predict that physiological systems involved in water balance will deteriorate with age at a reduced rate in these species. We quantified several components of water budgets for 14 species of Drosophila, including both desert and mesic representatives differing in their age of maturity. Desiccation resistance decreased with age in all but one species studied, primarily because of increased rates of water loss. However, there was no significant relationship between the rate of aging, as indicated by the rate of increase in water-loss rates as flies aged, and either habitat or age of maturity.     

Role of thermogenesis in the regulation of energy balance in relation to obesity

Obligatory thermogenesis is a necessary accompaniment of all metabolic processes involved in maintenance of the body in the living state, and occurs in all organs. It includes energy expenditure involved in ingesting, digesting, and processing food (thermic effect of food (TEF]. At certain life stages extra energy expenditure for growth, pregnancy, or lactation would also be obligatory. Facultative thermogenesis is superimposed on obligatory thermogenesis and can be rapidly switched on and rapidly suppressed by the nervous system. Facultative thermogenesis is important in both thermal balance, in which control of thermoregulatory thermogenesis (shivering in muscle, nonshivering in brown adipose tissue (BAT] balances neural control of heat loss mechanisms, and in energy balance, in which control of facultative thermogenesis (exercise-induced in muscle, diet-induced thermogenesis (DIT) in BAT) balances control of energy intake. Thermal balance (i.e., body temperature) is much more stringently controlled than energy balance (i.e., body energy stores). Reduced energy expenditure for thermogenesis is important in two types of obesity in laboratory animals. In the first type, deficient DIT in BAT is a prominent feature of altered energy balance. It may or may not be associated with hyperphagia. In a second type, reduced cold-induced thermogenesis in BAT as well as in other organs is a prominent feature of altered thermal balance. This in turn results in altered energy balance and obesity, exacerbated in some examples by hyperphagia. In some of the hyperphagic obese animals it is likely that the exaggerated obligatory thermic effect of food so alters thermal balance that BAT thermogenesis is suppressed. In all obese animals, deficient hypothalamic control of facultative thermogenesis and (or) food intake is implicated.     

Water balance in leaf tissue

Samples of the leaf tissue (14cm²) were placed in a plexiglass chamber which consisted of three parts. Water absorbed by the leaf tissue on one side of the sample was transported through the middle part of the sample to the opposite side and was transpirated there. The intensity of transpiration the intensity of water absorption and water saturation deficit (w.s.d.) were determined simultaneously in this tissue by gravimetry. Water balance was studied either in saturated samples of leaf tissue or in tissue where w.s.d. (10%, 20%, 30%, 40%) was established in advance. Although conditions for water absorption in leaf segments were optimal, w.s.d. originated in the saturated leaf tissue under all given external conditions (evaporation from 41.7 to 17.8 mg cm^?2 h^?1). W.s.d. which was established in advance for the most part increased during the experiment and reached even high values (more than 60%). the equilibration was reached only under conditions of low evaporation and initial w.s.d. higher than 20% in young leaves and higher than 30% in adult leaves. A positive correlation between the ratio of the intensity of water absorption to the intensity of transpiration and w.s.d. was found only under conditions of lower evaporation (17.8 and 23.2mg cm^?2h^?1). The maximal values of w.s.d. were limited in this way. Water balance was studied: 1. in leaf tissue of upper, middle and lower leaves of fodder cabbage, 2. in leaf tissue of middle leaves of young and adult plants of fodder cabbage, 3. in leaf tissue of dicots (fodder cabbage) with different vessel orientation in respect to water transport, 4. in leaf tissue of monocots (banana-tree) with water transport upright to the vessel orientation. Considerable change of water balance was observed when the water transport was prolonged by two incisions in the middle part of the sample. Results of all these experiments revealed the possibility of water stress origin even in leaf tissue sufficiently supplied with water.     

基于水量平衡下灌区农田系统中氮素迁移及平衡的分析

本文以于河套灌区典型灌域（前旗北疙堵乡塔布村）为研究对象,通过分析农田系统中水量平衡和氮素平衡,建立农田系统中氮素平衡和水分平衡的联立模型,并用此模型分析典型区域内农田系统中氮素随水分迁移的规律。分析表明：应用水量和氮平衡模型分析灌区农田系统中氮迁移及平衡,可以反映出农业面源污染物（氮）在整个农田系统中的去向,化肥使用量的降低和灌水量的减少,将有效的减少农田系统中氮素的输入量;秋灌—秋浇期间,玉米、番茄和葵花作物对氮的吸收率分别为17%、18%和32%,3种土壤中残留量分别为57%、60%和58%。依据河套灌区年施肥60万t计算,土壤残留量达到17.2万t。在秋灌-秋浇期间从黄河引入的氮总量达到1.21万t,随农田退水进入沟道的量为840 t。     

Application of the macroscopic electric charge balance in fermentation modeling

This article treats the application of the macroscopic electric charge balance in fermentation modeling. From the presented calculations it follows that the definition formula of the so-called degree of reduction is changed due to the ionic character of the fermentation reactants. It is also shown that the macroscopic electric charge balance, together with the ionic equilibria between fermentation reactants, leads to an expression for the calculation of the pH during fermentation. Finally it is concluded that one should be very careful in the estimation of biomass production from the acid or base feed rates which are necessary for pH control.     

Water balance of tissue segments from leaves of different insertion levels

Actual heterogeneity of indicators of water balance was studied on tissue segments from leaves ofBrassica oleracea L. v.acephala andNicotiana tabacum L. under controlled conditions. Maximal values of transpiration rate, water absorption rate, water transport rate and low values of WSD at the same time were observed at an initial WSD of 0% in segments from middle leaves and at an initial WSD of 20% mostly in segments from upper leaves. Although the properties of leaf tissue itself were probably the basic factors determining the actual heterogeneity of indicators of water balance, without connection with all other factors (e. g. various microclimates, supply of water) heterogeneity did not appear to a full degree.     

Chronic effect of atrazine on hydromineral balance in the crab

Effect in vivo of atrazine on total body weight, hydration level, haemolymph volume, inorganic electrolytes was studied in the gill, hepatopancreas and haemolymph of the crab. Significant changes were seen in the tissues indicating disturbances in the hydromineral balance of the crab as a consequence of atrazine.