PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “SPECIFIC GRAVITY”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6Linked to original sources
PubMed1987

The response to medical litholytic treatment of gallstones according to their specific gravity.

The buoyancy of gallstones was observed by taking anterior-posterior scout X-ray films of two patients standing during endoscopic retrograde cholangiography. In case 1, the large and small gallstones differed in buoyancy, and ursodeoxycholic acid treatment dissolved the floating small stones while failing to dissolve the nonfloating large stone. In case 2, both the large and small stones floated and are being dissolved by ursodeoxycholic acid treatment. Since floating or nonfloating and the plane of flotation depend on the specific gravity of the gallstone, the above findings suggest that a gallstone with a low specific gravity is more readily dissolved than one with a high specific gravity. The present method of estimating the buoyancy of gallstones was therefore considered extremely useful in selecting patients for medical litholytic treatment.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed1988

Rapid determination of egg weight and specific gravity using a computerized data collection system.

A rapid data-collection system for determining egg weight and specific gravity is described. The method links a microcomputer and an electronic balance to facilitate specific gravity determination by the displaced water (CADW) or Archimedes' method. Measurements obtained by this technique were compared with those determined by the saline flotation method. Repeatability measures showed both methods to be relatively precise. The CADW method was faster and reduced opportunities for clerical error.

Animals↗
PubMed1991

[Exercise-induced pathophysiological changes in asthmatic children. VIII. The changes of specific gravity of peripheral eosinophils and serum cortisol levels].

In order to investigate the mechanism of exercise-induced asthma (EIA) from the aspect of eosinophil function, we determined the changes in the peripheral eosinophil count and the specific gravity of the eosinophils in EIA patients, and also as a parameter of endocrine function, we determined the serum cortisol level. All parameters were analyzed in respect to time before and after inducement of exercise. The subjects selected for this study were 14 asthmatic children, an EIA positive group consisting of 8 subjects and 6 subjects in an EIA negative group. Eosinophil counts with a specific gravity less than 1.0825 gm/ml were recorded in respect to the time sequence of 15, 30, and 60 minutes after inducement of exercise. The eosinophil counts recorded were significantly higher in the EIA positive group in comparison to the EIA negative group. With progression of time after inducement of exercise, the number of eosinophils observed with a specific gravity of less than 1.0825 gm/ml tended to increase in the EIA positive group when compared to the results recorded before inducement of exercise. In respect to the course of time, 15 minutes after inducement of exercise, the serum cortisol level tended to decrease. At the point of 7 hours after inducement of exercise, the serum cortisol levels in the EIA positive group were significantly lower than the EIA negative group. These findings suggest that eosinophils and the endocrine system play an important role in EIA.

Adolescent↗
PubMed1984

Relationship between specific gravity, water content, and serum protein extravasation in various types of vasogenic brain edema.

Vasogenic brain edema was induced in cats by cold injury (six animals), brain tumors (five animals), and brain abscesses (six animals). Water and electrolyte content, specific gravity, blood volume, and the amount of extravasated serum proteins were determined in small tissue samples taken from gray and white matter at various distances from the lesion. Edema was strictly confined to the white matter of the affected hemisphere and declined from the lesion to the more peripheral regions. It was characterized by the extravasation of serum proteins and an increase of water and sodium content with little or unpredictable changes of potassium and blood volume. The calculated sodium content of edema fluid varied between 129 and 135 mueq/ml, and serum protein content between 8.1 and 11.9 mg/ml. In all three types of edema, specific gravity and water content correlated closely with the same slope and intercept of the calculated regression (y = 1.119-0.0011 x, r = -0.91). The results obtained indicate that the main denominator of specific gravity of edematous white matter is water content and that this relationship is not significantly altered by variations of blood volume or serum protein content.

Animals↗
PubMed1992

Experimental studies of the combined use of vitreous substitutes of high and low specific gravity.

The combined use of high and low specific gravity liquid vitreous substitutes has been studied in the rabbit. Eyes having undergone 1) vitreous replacement with silicone liquid combined with a perfluoropolyether liquid of high viscosity; 2) replacement with the perfluoropolyether or silicone alone; or 3) vitrectomy only (control) were compared under conditions of a cell-injection model of traction retinal detachment. Some of the control eyes (3 out of 9) and silicone-filled eyes (2 out of 10) developed total retinal detachments involving all quadrants; in the silicone-filled eyes the detachments extended behind the silicone globule. Conversely, in the eyes undergoing replacement with the two liquids or with the perfluoropolyether liquid alone, retinal detachments never extended to the inferior quadrants underlying the perfluoropolyether globule. In other experiments, the tendency toward emulsification of a low-viscosity perfluorocarbon liquid was reduced when it was used in combination with silicone liquid, in comparison to when this liquid was used alone.

Animals↗
PubMed1984

Assessment of specific gravity determined by Ames N-Multistix-SG.

Specific gravity (SG) was determined in 204 urines by N-Multistix-SG solid phase test strip. Seventy-seven of the urines were from patients with known renal disease or were positive for protein or glucose, or had pH greater than 6.4 (Group I) and were assayed for osmolality, SG by urinometer and refractometer, and several other parameters, intercorrelations were calculated. Osmolality was used as the gold standard. In Group I, correlation of osmolality with N-Multistix SG (r = 0.66) was not significantly different (p greater than 0.1) from that found with SG determined by refractometer (r = 0.72), or urinometer (r = 0.60). The correlation coefficient for 45 N-Multistix-SG values determined by two staff members was 0.91. For the 127 Group II normal urines, the correlation coefficient between Multistix-SG and SG by refractometer was 0.85. Multistix-SG avoids the errors related to large molecules such as glucose and radiographic contrast media seen with SG determined by urinometer and refractometer (uncorrected for glucose) and was found to have comparable accuracy to these two methods when compared with osmolality, in patients with known renal disease or abnormal urinalysis.

Humans↗
PubMed2006

Urine specific gravity in exercisers prior to physical training.

Urine specific gravity (USG) is used as an index of hydration status. Many studies have used USG to estimate pre-exercise hydration in athletes. However, very little is known about the pre-exercise hydration status of recreational exercisers. The purpose of the present study was to measure the pre-exercise USG in a large sample of recreational exercisers who attended 2 different fitness centers in the United States. In addition, we wanted to determine if factors such as time of day, geographic location, and gender influenced USG. We tested 166 subjects in Chicago and 163 subjects in Los Angeles. Subjects completed a survey on their typical training regimen and fluid-replacement habits, and thereafter voided and delivered a urine sample to the investigators prior to beginning exercise. Samples were measured on site for USG using a hand-held refractometer. The mean (SD) USG was 1.018 (+/- 0.007) for all subjects. Males had a higher average USG (1.020 +/- 0.007) when compared with females (1.017 +/- 0.008; p = 0.001). Despite differences in climate, no difference in mean USG occurred based on location or time of day. Based on standards used for athletes (USG > or = 1.020), 46% of the exercisers were likely to be dehydrated.

Adolescent↗
PubMed1984

[A longitudinal study of specific gravities of whole blood in dyestuff plant workers].

Specific gravities of whole blood (GB) have been used widely as a screening test of anemia in industrial surveillance systems in Japan. The recent spread of electronic computers enables us to make effective use of a large quantity of information and GB could be used to screen examinees more accurately if the various factors which can bring about fluctuations in GB or the data obtained through past health examinations are taken into consideration. Time trends of GB can be explained by the combination of the physiological effect of aging, environmental factors such as diet or working conditions, and the birth cohort effect. The present study was aimed to identify the factors which bring about fluctuations in GB through longitudinal as well as cross-sectional observations. The study subjects consisted of 1,105 male workers engaged in dyestuff production work or clerical work at a dyestuff plant located in Tokyo during the period from 1953 to 1976. Though a negative association was found between GB and the age of workers through cross-sectional observations, it was found through longitudinal observations that the individual GB had a tendency to rise during the period in each birth cohort. These facts suggest that some environmental factors acted so as to raise the individual GB during this period in opposition to the physiological effect of aging to lower it. In order to evaluate the associations of educational history, working conditions, age and physique of workers with GB, information on these factors obtained through health examinations in 1960, 1965, 1970 and 1975 was analyzed separately by the multi-dimensional contingency table method. As a result, it was demonstrated that GB was directly related to all of these factors in 1960 and 1965, to age and physique in 1970 and only to age in 1975. These results suggest that environmental factors associated with educational history or working conditions played a greater part in the earlier periods when the average GB was not as high as in the later periods. In summary, the efficiency of GB as a screening test will be considerably improved if the judgment criteria utilize information about these environmental factors as well as the physiological effect of aging based on the information obtained from this study.

Adult↗
PubMed1978

Shell gland oxygen consumption in hens producing eggs of low or high specific gravity.

Oxygen consumption of shell gland lumenal tissue was found to be higher in hens producing eggs of high specific gravity (greater than or equal to 1.080) when compared to tissue from hens producing eggs of low specific gravity (less than or equal to 1.075). Shell gland lumenal tissue oxygen consumption was also greater when an egg was in the shell gland as compared to hens with an egg in the magnum (9.8 and 8.0 microliter O2/hr/mg tissue respectively).

Animals↗
PubMedDate not supplied

Acute effect of angiographic contrast medium on cortical specific gravity after middle cerebral artery occlusion in rats.

Early angiography after cerebral arterial occlusion has been cited as potentially detrimental. This investigation evaluates the effect of acute angiographic contrast medium administration on the cortical edema induced by middle cerebral artery (MCA) occlusion. Sixteen rats underwent MCA occlusion, and after 1 hour half the rats underwent ipsilateral internal carotid injection of meglumine diatrizoate, whereas the remainder underwent cervical internal carotid exposure only. Six rats had only sham operations on the MCA and internal carotid, and 4 other rats served as normal controls. Cortical specific gravity was measured to reflect cerebral edema 4 hours after occlusion or sham operation. Specific gravity of the lateral frontal cortex in the hemisphere ipsilateral to occlusion was 1.0396 +/- 0.0011 (mean +/- SEM) when no angiographic contrast medium was administered, significantly less (p less than 0.01) than in rats exposed to contrast medium (specific gravity 1.0442 +/- 0.0005). The latter value was not significantly different from normal. Other cortical areas on the side of the contrast medium injection were also relatively dehydrated compared with normal controls. Early meglumine diatrizoate administration after MCA occlusion results in a decrease in cerebral cortical edema, possible by inducing an osmotic gradient that draws water from the extravascular space.

Animals↗
PubMed2003

Effect of furosemide on urine specific gravity and osmolality in thoroughbred racehorses.

Postrace urine samples from thoroughbred horses were examined to compare osmolality and specific gravity between horses treated with furosemide and those not treated. Samples were assigned to groups in relation to reported medication (furosemide) status, race finish position, and distance of race. Urine osmolality was significantly (P <.05) lower in samples from horses treated with furosemide when compared with untreated horses. Specific gravity determinations are less precise at measuring urine osmolality at lower levels (1.01 g/ml or less). The measurement of osmolality is a superior method for determining the urine solute concentration and facilitating the regulation of furosemide.

Animals↗
PubMed1977

Variation in the weight, specific gravity and composition of the antlers of red deer (Cervus elaphus L.).

1. Antlers were removed in September from 2-4 year old red deer (Cervus elaphus L.). Both well-fed penned stags and less well-nourished grazing stags were studied. 2. For deer of the same age, both log antler weight and log antler specific gravity were related to body-weight in September and to body-weight gain between March and September. The antlers of 3- and 4-year-old stags were heavier and tended to be denser relative to body-weight and body-weight gain than those of 2-year-old stags. 3. For grazing stags of a given age, antler weight and specific gravity, and body-weight and body-weight gain, were progressively less in the three successive years of the study. This appeared to reflect increasing stocking rate over this period. 4. The composition of the antlers did not vary significantly between penned and grazing stags or with age. However the concentrations of ash, phosphorus and magnesium in dry matter showed significant positive correlations with specific gravity, that of zinc a significant negative correlation, while calcium, copper and manganese showed no significant correlation. 5. The antlers evidently provide a useful index of the changes in body-weight of the stags.

Animal Nutritional Physiological Phenomena↗
PubMed1976

[Urine specific gravity and osmolarity in hypertension patients with dehydration].

Results are reported from the comparative investigations of kidney concentration function by urine specific gravity and its osmolatity of 58 patients with arterial hypertension. Significant differences were found in more of the half of the patients. On the base of certain theoretical prerequisites and possibilities of technical errors was concluded that the determination of the maximal urine osmolality is a more reliable and more accurate index for the actual renal concentration ability. Urine specific gravity can be used in the everyday clinical practice due to the more convenient and easier determination. Urine osmolality must be used predominantly in scientific-clinical studies.

Adult↗
PubMedDate not supplied

Intra- and interindividual variation in urine osmolality and urine specific gravity in healthy pet dogs of various ages.

Urine specific gravity (Usg) and urine osmolality (Uosm) are used routinely to assess renal concentrating ability, but limited data on these variables are available for healthy dogs. Consequently, we studied the intra- and interindividual variations in Usg and Uosm in healthy dogs as well as the influence of age and gender on these variables. Dogs were selected for health and anestrus in female dogs through the use of a detailed questionnaire. Eighty-nine owners collected morning and evening urine samples from their dogs on 2 consecutive days. In 8 dogs in which the Uosm of different samples varied more than 50%, owners collected urine for 24 hours at 2-hour intervals during the day and at 4-hour intervals at night. The possible effect of changes in adrenocortical function with age was assessed by measurements of urinary corticoid/creatinine (C/C) ratios. Among all samples, Uosm ranged from 161 to 2,830 mOsm/kg and Usg from 1.006 to > 1.050. In the morning, Uosm (1,541 +/- 527 mOsm/kg, range 273-2,620 mOsm/kg) and Usg (1.035 +/- 0.010, range 1.009-->1.050) were higher than in the evening (Uosm 1,400 +/- 586 mOsm/kg, range 161-2,830 mOsm/kg; Usg 1.031 +/- 0.012, range 1.006-->1.050). The interindividual coefficient of variation in Uosm was 34.2% for morning urine samples and 41.9% for evening samples. In 8 dogs with large differences in urine concentration, there were 2- to 3-fold increases or decreases in Uosm during the day, and the intraindividual coefficient of variation was 33.0%. There was no relation between gender and urine concentration. Urine concentration in both the morning and evening samples decreased with age. Urinary corticoid/ creatinine ratios did not change with age. It can be concluded that Uosm and Usg vary widely among healthy dogs. Urine concentration is generally lower in the evening than in the morning and is not related to gender. Urine concentration decreases with age, and this cannot be ascribed to an associated increase in endogenous corticoids. In some dogs, Uosm varies widely during the day, with an intraindividual coefficient of variation approaching the interindividual coefficient of variation. This may be regarded as a biologic variation but also could represent an early undiagnosed clinical abnormality.

Adrenal Cortex Hormones↗
PubMed1995

[Density, specific gravity and baricity of various spinal anesthetics and those of normal human cerebrospinal fluid in Japanese].

We measured the density and specific gravity at room (20 degrees C) and body (37 degrees C) temperatures of spinal anesthetic solutions, which have been commercially prepared in Japan. Solutions investigated were; (1) 0.4 % and 0.5 % tetracaine (T) in water, 0.5 % T in normal saline, 5 % glucose and 10 % glucose, (2) 0.3 % dibucaine in 5 % sodium chloride: (P), (3) 0.24 % dibucaine with 0.12 % tetracaine in 9.5 % glucose: (N); (4) 3 % lidocaine in 8.5 % glucose: (X); and (5) 0.5 % bupivacaine in water containing preservatives: (M). We also determined the density and specific gravity of normal human cerebrospinal fluid (CSF) in Japanese (n = 10) at 37 degrees C. Each local anesthetic solution was classified into hyperbaric, isobaric or hypobaric solution. Thirty seven centigrade 0.5 % T in normal saline and 37 degrees C 0.5 % M in water had the density comparable to 37 degrees C human CSF and were considered to be relatively isobaric solutions. Our data demonstrated that human CSF had various densities. Therefore, it is possible that these isobaric solutions would vary their pharmacodynamic profiles in intrathecal use according to individual CSF characteristics and temperature of the solution.

Anesthesia, Spinal↗
PubMed1987

Unilateral vesicoureteral reflux in children. study on urine specific gravity, osmolality, beta-2-microglobulin and lactoferrin.

Vesicoureteral reflux was defined as unilateral in 17 of 36 cases. Urine was collected from both kidneys. Urine specific gravity and osmolality were significantly reduced; beta 2-microglobulin was elevated and lactoferrin depressed on the reflux side. We also observed a significant correlation between specific gravity or osmolality on one side and lactoferrin on the other side, and between osmolality and beta 2-microglobulin. These observations showed a depressed concentrating capacity and reduced tubular absorption of beta 2-microglobulin suggesting reduced tubular function on the reflux side.

Child↗
PubMed1992

Effect of microbial fermentation on functional specific gravity of small forage particles.

Two experiments were designed to determine the effect of gas production during in vitro digestion on functional specific gravity (FSG) of forage particles. In Exp. 1, FSG of ground alfalfa hay decreased from 1.123 to 1.049 between 3 and 9 h of incubation and increased thereafter to reach a plateau at 1.309 after 30 h of incubation. Gas production peaked at 6 h, but gas associated with particles increased until 9 h of incubation. Gas associated with solid residue was correlated to gas production (r = -.67) but also was influenced by gas holding capacity and rate of escape from the particles. In Exp. 2, measurements were performed on ground alfalfa hay, alfalfa silage, and bromegrass hay containing 42.6, 35, and 66.4% NDF, respectively. Gas production seemed to be related to the amount of readily available substrate. Although at 9 h of incubation more gas was produced by alfalfa silage (.235 mL.min-1.g of DM-1) than by bromegrass hay and alfalfa hay (.087 and .187 mL.min-1.g of DM-1, respectively), gas associated with particles was greater for alfalfa hay (.416 mL/g of DM) than for bromegrass hay and alfalfa silage (.256 and .281 mL/g of DM, respectively). The increase in FSG was more rapid for alfalfa silage than for the hays. After 27 h of digestion, gas associated with particles (milliliters per gram of DM) and FSG were .164, 1.226; .147, 1.235; and .001, 1.467 for bromegrass hay, alfalfa hay, and alfalfa silage, respectively. Gas produced during fermentation delayed the increase in specific gravity of forage particles.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗