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1.
While the beta-glucuronidase activity of intact cells of Clostridium perfringens was higher in 0.95% sodium chloride (NaCl) than that in 0, 0.1 or 0.5%, that of Escherichia coli was higher in 0.1% NaCl than that in 0, 0.5 or 0.95% NaCl in 0.1 mol l-1 KH2PO4. However, the enzyme activity of both species of intact cells was higher in buffer containing 16 mEq sodium, 134 mEq potassium and 16 mEq chloride per litre than in that containing 146 mEq sodium, 13 mEq potassium and 146 mEq chloride. These findings suggest that bacterial cells are affected by the presence of NaCl and that the effect of NaCl on the activity of bacterial beta-glucuronidase may differ by location in the large intestine.  相似文献   

2.
Amphotericin B is an effective therapeutic agent for most systemic or invasive mycoses, but its usefulness is limited by the frequent occurrence of nephrotoxicity. Given the high and increasing frequency of serious fungal infections, especially in immunocompromised patients, the importance of the morbidity caused by this toxicity is substantial. Salt loading may prevent and even reverse amphotericin B-induced azotemia by an unknown mechanism. A prospective, randomized, placebo-controlled trial in a relevant patient group would strengthen the support for this simple, safe therapy, but will not likely be carried out because of practical and ethical considerations. Thus, a few prospective and limited controlled human studies may be the only supportive evidence for using this therapy. Supplementing dietary sodium chloride intake with 150 mEq of sodium chloride daily intravenously or orally beginning when or before amphotericin B therapy is initiated will likely prevent much of the observed nephrotoxicity and should be carried out routinely.  相似文献   

3.
A formal metabolic study of carbenoxolone sodium (Biogastrone) 300 mg./day has been performed for 17 days on a woman with gastric ulcer who in a previous 21-day trial, on a 52-mEq sodium diet, showed weight gain, retention, and rise in plasma sodium and chloride concentrations, as well as hypokalaemia without change in potassium balance. In the present trial sodium intake was restricted to 26 mEq/day; while plasma electrolyte changes of lesser degree still occurred, there was no retention of water, sodium, or chloride. Aldosterone secretion in the control period was 202 μg./24 hours, and fell to 74 μg./24 hours after carbenoxolone, but plasma renin was unchanged.These results suggest that the mineralocorticoid effects of carbenoxolone (and presumably of liquorice and its other derivatives) are due to an intrinsic aldosterone-like action, and that, with sodium deprivation, aldosterone secretion is suppressed by a mechanism which is not renin-mediated—possibly hypokalaemia.  相似文献   

4.
The mean sodium concentration of 61 gastrointestinal aspirations in peritonitis was 103 mEq/l. (S.D. 16·66), of 16 aspirations in vagotomy 88 mEq/l. (S.D. 19·49), of 12 aspirations in perforated duodenal ulcer 81 mEq/l. (S.D. 19·49), and of 15 aspirations in intestinal obstruction 89 mEq/l. (S.D. 19·49). The mean potassium concentrations were 9, 9·9, 13, and 8·8 mEq/l. respectively, and the mean chloride concentrations 122, 131, 125, and 112 mEq/l. respectively. It is suggested that a gastrointestinal replacement solution should contain 100 mEq of sodium, 12 mEq of potassium, and 122 mEq of chloride per litre; 50 g. of dextrose or 100 g. of fructose may be added to provide energy.  相似文献   

5.
Twenty patients with mild or moderate essential hypertension and not receiving any drug treatment, who had been moderately restricting their sodium intake to around 70 mmol(mEq) a day for at least one month and whose mean blood pressure was then 163/103 mm Hg, were entered into a double blind, randomised crossover study to compare one month''s treatment with slow release potassium chloride tablets (64 mmol potassium chloride a day) with one month''s treatment with a matching placebo. Mean (SEM) urinary sodium excretion on entry to the study was 68 (6.8) mmol/24 h. Mean urinary potassium excretion increased from 67 (6.9) mmol(mEq)/24 h with placebo to 117 (4.6) mmol/24 h with potassium chloride. Supine and standing systolic and diastolic blood pressures did not change significantly with potassium chloride supplementation when compared with pressures while receiving placebo or before randomisation. In patients who are able moderately to restrict their sodium intake doubling potassium as a chloride salt has little or no effect on blood pressure.  相似文献   

6.
The effects of sodium deprivation for 10 d, a period sufficient to induce sodium appetite, on gustatory nerve discharges in rats were determined. Chorda tympani responses to concentration series of sodium chloride, sucrose, hydrochloric acid, and quinine hydrochloride were recorded and analyzed without the experimenter knowing the animal's deprivation condition. After deprivation, both whole nerve and single nerve fiber responses to sodium chloride were smaller; NaCl-best fibers, those more responsive to sodium chloride than to sucrose, hydrochloric acid, or quinine, were most affected. Thresholds had not changed; however, slopes of the stimulus-response functions for sodium chloride were lowered. Comparable changes in responses to the other stimuli did not occur. These results were discussed with respect to a possible relationship between changes in sodium chloride responsivity and changes in sodium intake, differences between methods of inducing sodium appetite, coding of taste quality and intensity, and mechanisms which might effect the responsivity change.  相似文献   

7.
A defined medium of low osmolarity was developed permitting growth of Rhizobium meliloti with generation times of approximately 2.8 h doubling-1. The effects of sodium, potassium, magnesium, ammonium, chloride, sulfate, phosphate, bicarbonate and acetate ions on the growth rate of R. meliloti were determined. Sodium, potassium and ammonium ions had little effect on growth at concentrations of 100 mEq or less; magnesium ion inhibited growth severely at concentrations of 50 mEq (25 mM). Of the anions, chloride and sulfate appeared to have little effect while phosphate, bicarbonate, and acetate inhibited growth at concentrations of as little as 25 mEq. The addition of proline, glutamate, or betaine to cells growing in inhibitory concentrations of NaCl did not relieve the inhibition. When grown in the presence of inhibitory levels of NaCl, the intracellular concentration of glutamate but not of proline or gamma amino butyric acid increased 5-fold.  相似文献   

8.
NASSERY  H.; BAKER  D. A. 《Annals of botany》1974,38(1):141-144
The quantity of sodium transported to the shoots of intact barleyplants was stimulated by 0·5 mM ouabain when the sodiumchloride level of the bathing medium was below 100 mM. At sodiumchloride concentrations of 100 mM or more this ouabain-stimulatedsodium transport was not observed. Equiosmotic mannitol, equimolarpotassium chloride or equivalent calcium chloride solutionsdid-not affect the ouabain-stimulated sodium transport froma basic medium containing 10 mM sodium chloride. It is suggestedthat under the present experimental conditions the increasedsodium uptake by the root cells at sodium chloride concentrationsof 100 mM or more masks the extrusion process.  相似文献   

9.
Human erythrocytes suspended in isotonic lactose solution lost potassium and continued to lose potassium even when resuspended in isotonic sodium chloride. The same phenomenon was observed when the cells were suspended in an isotonic solution of the sodium salt of glutamate, a nonpenetrating anion. The presence of 5 mEq per liter of sodium chloride in the lactose or sodium glutamate suspensions greatly reduced the initial potassium loss and the potassium loss when the cells were resuspended in sodium chloride solution. Salts of nonpenetrating anions were less or not effective in blocking lactose damage. The results indicate that absence of penetrating anions in the suspending media is the initiating condition of lactose damage. Chloride and consequently potassium are lost from the erythrocyte. Changes in cellular ionic pattern and/or changes in the cell membrane result in a nontransient damage manifested by continued potassium loss by lactose-treated cells resuspended in isotonic NaCl.  相似文献   

10.
This study was made to investigate changes in serum and muscle ion concentrations and related mortalities in maturingAnguilla rostrata migrating down the St. Lawrence Estuary. Mortalities take place in the freshwater portion of the St. Lawrence. Electrolyte concentrations of moribund eels taken in freshwater were compared to those of freshwater and salt water controls. Moribund eels had a much lower serum osmolality (270 mOsm/kg) than the controls (328 and 358 mOsm/kg). This resulted from low sodium (125 mEq/l) and particularly low chloride (69 mEq/l) contents in the moribund eels compared to the freshwater controls (153 and 117 mEq/l) and the salt water controls (179 and 137 mEq/l). There was also a general decrease in muscle ion concentrations in moribund eels though the percentage water was similar to that of the freshwater controls (64.0 and 63.7%). The changes measured between the freshwater controls and the salt water controls in nature are similar to those measured onAnguilla anguilla in laboratory. These results suggest that mortalities are related to failure by some of the maturing eels to maintain their mineral balance in freshwater. Hypothesis is made that maturing eels migrating long distances in freshwater or retarded by physical or chemical barriers, start to excrete sodium and chloride under hormonal control before they have reached brackish water. In the conditions that prevail in the St. Lawrence Estuary, this results in mineral unbalance and possibly in mortalities.  相似文献   

11.
The combined effects of pH, sodium chloride, and sodium nitrite were studied by using a dialysis sac technique in brain heart infusion broth. Growth and enterotoxin A production by Staphylococcus aureus strain 100 were found to decrease with the addition of sodium nitrite, with a decrease in pH from 7.0, and with an increase in sodium chloride concentration. The significance of these results is discussed in relation to cured meats.  相似文献   

12.
Sodium cotransport systems in epithelial secretion   总被引:1,自引:0,他引:1  
1. After considering the direct coupling and indirect coupling to the sodium gradient in sodium-dependent secretion across epithelia, the properties of the Na-K-Cl cotransporter involved in active chloride secretion and active chloride absorption are summarized. 2. A comparison between cellular mechanism of secretion and absorption shows that the direction of transepithelial transport is determined mainly by the intracellular localization of sodium cotransport systems and sodium-independent leaks. 3. Sodium cotransport systems, performing a similar function in various epithelia or species, may provide a powerful model to study their function at a molecular level.  相似文献   

13.
Summary On adapting brackish waterAnguilla anguilla to fresh water it was noted that, while the plasma sodium, magnesium,pCO2 and pH were held reasonably constant, there was a substantial fall in chloride concentration (–33 mEq). The gradient of the linear correlations between plasma sodium and chloride also fell (brackish water gradient=0.92, fresh water gradient=0.21) indicating that a new pattern of plasma ion interrelationships was being established. Comparison with plasma Na/Cl ion ratios from other fishes suggested that this phenomenon was peculiar toA. anguilla. Corresponding with the very low plasma chloride levels plasma bicarbonate was four to five times that found in other fishes, and this was thought related to the finding that the haematocrit value almost doubled during adaptation to fresh water. In fresh water adapted fish a fall in plasma chloride was associated with a rise in plasma bicarbonate, however the charge compensation effect of this response was only partial as summing the common plasma cations and anions left an anion deficit of about 34 mEq to be accounted for.  相似文献   

14.
The present study was designed to determine the changes in serum sodium, anion gap, different antioxidants and free radicals in preeclamptic patients and control subjects. Serum sodium, chloride, bicarbonate, calcium, potassium and magnesium were estimated and anion gap was determined in 100 proteinuric hypertensive and 100 normotensive pregnant women. Mean serum sodium, chloride and bicarbonate level (133.26 ± 13.1, 104.97 ± 11.37, and 22.01 ± 4.66 mEq/l, respectively) were significantly higher in proteinuric hypertensive women as compared to controls (125.85 ± 10.4, 101.90 ± 6.3, 19.34 ± 3.21 mEq/l, respectively) whereas anion gap level (6.28 ± 16.147) was nonsignificantly higher in proteinuric hypertensive as compared to normotensive (4.61 ± 11.84). Total serum sodium concentration increases in preeclamptic subjects, the exact distribution of serum sodium in various compartments of the body are not clear and correlation of serum sodium and anion gap with proteinuria is also not known. The levels of different antioxidants were decreased in preeclamptic patients as compared to the controls while the level of free radicals elevated in preeclamptic subjects as compared to controls. In our study, anion gap level was found to be rather non-significantly higher in proteinuric hypertensive women as compared to normotensive women.  相似文献   

15.
AIMS: Combinations of sodium chloride and acid are frequently used to inhibit growth of spoilage and pathogenic bacteria in food. The influence of differing sodium chloride, lactate and pH values on the growth of stressed and unstressed cells of a non-toxigenic strain of Escherichia coli O157:H7 was studied. METHODS AND RESULTS: At pH 5.5 or 6.0, there was little or no effect on the growth rate in the presence of lactate and/or sodium chloride, but the lag times were longer as the lactate concentration increased. At pH 5.0, in the absence of sodium chloride, increasing the lactate concentration increased the growth rate and the lag time; no growth occurred in the presence of 1.5 g 100 g(-1) lactate. In the presence of 4-6 g 100 g(-1) sodium chloride, growth occurred at 1.5 g 100 g(-1) lactate. The growth rate was similar at all lactate concentrations. CONCLUSION: The results demonstrate that the presence of sodium chloride promoted growth of E. coli O157:H7, especially under stressful conditions of low pH. Significance and Impact of the Study: These findings could have implications for the use of acid and sodium chloride as a preservation treatment for the inhibition of E. coli O157:H7 in food.  相似文献   

16.
Increasing concentrations (2, 4 and 8% w/v) of sodium chloride in the heating medium progressively reduced the heat resistance of spores of Bacillus stearothermophilus. Storage at 4° in water or in sodium chloride solutions had little effect on viable counts of unheated spores, but with the increase in sodium chloride concentration there was a reduction in the heat activation effect and a small decrease in heat resistance of the spores. Increasing the severity of heat treatment rendered spores increasingly sensitive to sodium chloride in the plating medium.  相似文献   

17.
The mass changes of sodium, potassium, and calcium ions in the rat uterine secretion at blastocyst delay, activation, and attachment have been estimated with X-ray microanalyses of samples of uterine secretions absorbed by small Sephadex beads. A quantification of the ions was attempted by using a standardized coat of gold on the beads as a reference element for normalization of the ion peaks and by fitting the normalized values into corresponding linear regression equations obtained from measurements of step-wise dilutions of a control rat serum. The concentrations of sodium observed at delay, activation, and attachment were 117, 201, and 203 mEq/l, respectively, and those of potassium were 6, 18, and 19 mEq/l, respectively. Calcium values were about 2 mEq/l and decreased at attachment. Among the anions, only the chloride concentration increased at activation and attachment.  相似文献   

18.
肝素钠精制工艺研究   总被引:1,自引:0,他引:1  
为提高肝素钠粗品效价,改善产品色泽,采用二次盐解、双氧水氧化和脱色等工艺对肝素钠粗品进行精制,并探讨工艺条件对产品效价、收率的影响。结果得到最佳精制工艺条件:盐解质量浓度为2%,盐解pH为8.0,醇沉体积浓度45%,氧化剂(双氧水)体积分数为3%。该精制工艺能够有效地提高效价(平均比粗产品提高1.5倍),收率较高,并具有操作简便、省时等特点。  相似文献   

19.
Sodium Movement across Single Perfused Proximal Tubules of Rat Kidneys   总被引:15,自引:2,他引:13       下载免费PDF全文
Using perfusion techniques in single proximal tubule segments of rat kidney, the relationship between net sodium movement and active transport of ions, as measured by the short-circuit method, has been studied. In addition, the role of the colloid-osmotic pressure gradient in proximal transtubular fluid and sodium movement has been considered. Furthermore, the limiting concentration gradient against which sodium movement can occur and the relationship between intratubular sodium concentration and fluid transfer have been investigated. Comparison of the short-circuit current with the reabsorptive movement of sodium ions indicates that this process is largely, perhaps exclusively, active in nature. No measurable contribution of the normally existing colloid-osmotic pressure gradient to transtubular water movement was detected. On the other hand, fluid movement across the proximal tubular epithelium is dependent upon the transtubular sodium gradient and is abolished when a mean concentration difference of 50 mEq/liter is exceeded.  相似文献   

20.
E. W. Henry  C. R. Rally 《CMAJ》1963,89(5):206-213
Electron microscopic details of the glomerular and tubular lesions in a 26-year-old man with angiokeratoma corporis diffusum are presented. Though unable to concentrate urine above a specific gravity of 1.012, this patient showed preservation of the ability to acidify and alkalinize the urine following oral loads of ammonium chloride (150 mEq./day) and sodium bicarbonate (158 mEq./day) for several days. This observation is in contrast to previously reported findings and suggests that the regularly observed hyposthenuria in this disease does not depend on defects in ion transfer in the distal tubule system.  相似文献   

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