scholarly journals DETERMINATION OF TRITIUM IN MICROGRAM TISSUE SAMPLES: DISTRIBUTION OF EXOGENOUS 3H-CHOLESTEROL IN THE RAT ADRENAL CORTEX

1971 ◽  
Vol 19 (1) ◽  
pp. 46-50 ◽  
Author(s):  
MARTTI PARVINEN ◽  
MIKKO NIEMI
Keyword(s):  
Dry Weight ◽  
Cortical Layers ◽  
Ether Anesthesia ◽  
Tissue Samples ◽  
Unilateral Adrenalectomy ◽  
Tritium Activity ◽  
Metal Cathode ◽  
Thick Steel ◽  
The Mean

An internal sample metal cathode proportional counter for measurements of low tritium activity in biologic samples of microgram size has been designed. Using a guard detector operating in anticoincidence together with a thick steel castle, a background of 0.5 cpm and an efficiency of 54.6% for tritium were realized. Radioactivities down to 2 pC (4.4 dpm) can be measured with an accuracy of ±16%. Tritium activity was measured in single adrenal cortical sections of 7 µm in thickness and 0.4 mm in diameter having a mean dry weight of 1.2 µg. The cortical layers were identified histologically from alternate sections. Two days after the injection of tritiated cholesterol the highest radioactivity was encountered in the outer fascicular zone (39 dpm/µg). The distribution of the radioactivity within the cortex was equal in all animals, although the mean level varied individually. The glomerulosa and reticularis contained usually about one-third of the activity in the outer fasciculata. Ether anesthesia and unilateral adrenalectomy caused significant decrease in the incorporation of the cholesterol, which was not further reduced by an injection of adrenocorticotropin. Ninety-five per cent of the radioactivity in the adrenals was bound to cholesterol or its esters 2 days after the injection.

scholarly journals STUDIES IN HISTOCHEMISTRY: LXXXII. DETERMINATION OF VITAMIN A IN MICROGRAM SAMPLES OF TISSUE AND ITS QUANTITATIVE HISTOLOGICAL DISTRIBUTION IN THE RAT ADRENAL

1965 ◽  
Vol 13 (8) ◽  
pp. 640-646 ◽  
Author(s):  
PAUL K. NAKANE ◽  
DAVID GLICK
Keyword(s):  
Standard Deviation ◽  
Vitamin A ◽  
Analytical Data ◽  
Dry Weight ◽  
Optimal Conditions ◽  
Protein Nitrogen ◽  
Tissue Samples ◽  
The Mean ◽  
Mean Concentration

A fluorometric procedure is presented for the determinations of vitamin A in small tissue samples, e. g., microtome sections, to enable correlation of analytical data with histology. Measurements may be made over the range, 3 x 10–12–6 x 10–10 moles of the vitamin (0.86-17 mµg of vitamin A alcohol), the quantities per 60 µl of solution used in the microcuvettes for fluorometry. Optimal conditions for certain of the analytical steps and for extraction of the vitamin from tissue were studied. Quantitative recoveries of vitamin added to tissue were obtained, and the reproducibility of the analysis of tissue was observed to have a standard deviation of 4%. In preliminary experiments, a mean vitamin A per rat adrenal was found to be 2.3 mµmoles, and the mean concentration 317 mµmoles/g, dry weight. A study of the quantitative histological distribution of the vitamin in the adrenal revealed greatest concentrations (4.7 x 10–12 moles/µg of proten-nitrogen) in the region where the glomerulosa and fasciculata join, and the concentration fell steadily through the fasciculata and reticularis to a low (0.9 x 10–12 moles/µg of protein-nitrogen) in the medulla.

scholarly journals Determination of trace elements in the plants of Mt. Bozdag, Izmir, Turkey

2010 ◽  
Vol 62 (3) ◽  
pp. 731-738 ◽  
Author(s):  
D. Yildiz ◽  
I. Kula ◽  
G. Ay ◽  
S. Baslar ◽  
Y. Dogan
Keyword(s):  
Trace Elements ◽  
Woody Plants ◽  
Statistical Significance ◽  
Absorption Spectrometry ◽  
Dry Weight ◽  
Current Level ◽  
The Mean ◽  
Herbaceous And Woody Plants ◽  
Made In

The aim of this study was to determine the current level of atmospheric heavy metal content on the Bozdag Mountain of the Aegean Region, Turkey. Twenty nine different plants were selected to study their potential as biomonitors of trace elements such as Ni, Zn, Fe, Pb, Mn and Cd (?g g-1, dry weight). The samples were collected from two different altitudes of Mt. Bozdag. The concentrations of trace elements were determined by atomic absorption spectrometry. The mean concentrations determined at 1000 m altitude ranged from 0.025 to 1.609, 0.232 to 0.731, 0.578 to 5.983, 0.287 to 0.565 and 0.176 to 2.659 (?g g-1, dry weight), for Ni, Zn, Fe, Pb and Mn, respectively. At the altitude of 1600 m, the values ranged from 0.023 to 0.939, 0.258 to 1.254, 0.839 to 5.176, 0.301 to 1.341 and 0.405 to 3.351 (?g g-1, dry weight) for Ni, Zn, Fe, Pb and Mn, respectively. No Cd was detected at either altitude. Statistical significance was determined by the independent sample t-test and comparisons were made in order to determine if there were any differences between the averages of herbaceous and woody plants. .

MINERALIZATION OF AORTIC WALL - PIXE STUDIES

1992 ◽  
Vol 02 (04) ◽  
pp. 551-567 ◽  
Author(s):  
E. ROKITA
Keyword(s):  
Mathematical Description ◽  
Vessel Wall ◽  
Aortic Wall ◽  
Mineralization Process ◽  
Tissue Samples ◽  
Animal Material ◽  
The Mean ◽  
Pixe Method ◽  
Human Autopsy

The application of PIXE and micro-PIXE methods for the description of human aortic wall mineralization including its dynamics is presented. The data was collected both from human autopsy samples and from animal material. The mean concentrations of P, S, Cl, K, Ca, Fe, Cu, Zn, Br, Sr and Pb were determined in tissue samples and in the aortic wall sections. On the basis of PIXE results the following conclusion may be drawn: the concentrations of Ca, Zn, Sr and Pb increase while that of S, Cl and K contents decrease when the mineralization of the vessel wall (determined histochemically) develops. The micro-PIXE method enabled: (1) the determination of the elemental composition of both inorganic and organic materials in the sample, (2) the identification of different Ca—P compounds on the basis of the Ca/P ratio, (3) the investigations of the involvement of other elements in the development of mineralization process (4) the determination of the deposit radii on the basis of Ca concentration and (5) the generalized analysis on the inorganic deposit growth using mathematical description.

scholarly journals Determination of the moisture content of white and yellow corn from ohaji in imo state of nigeria using the dry-weight technique

2018 ◽  
Author(s):  
Offurum Julius Chigozie ◽  
C.M. Morgan
Keyword(s):  
Moisture Content ◽  
Dry Weight ◽  
Mean Value ◽  
Seed Moisture Content ◽  
Imo State ◽  
Yellow Corn ◽  
Seed Moisture ◽  
The Mean ◽  
High Constant Temperature

The water content determination of two maize species (Yellow corn- and White corn- ) located at Ohaji in Imo State of Nigeria were  considered in this study. This was motivated by the regular reported cases of the seed post-harvest spoilages, especially in the local communities. And the moisture content of a particular seed could vary according to the various location of crop, presumably due to the soil texture. The moisture content of a given crop seed can influence its storage value, as well as its choice of selection during manufacturing processes. It was, thus, necessary to determine the moisture content of the two maize species (white and yellow corn) from Ohaji in Imo State of Nigeria, in order to identify their dispositions, especially during storage. Modified High Constant Temperature Oven method, as prescribed by the International Seed Testing Association (which involves preliminary pre-drying and grinding), was employed, at a temperature of 102oC. This involved the use of dry-weight technique, which is expressed as a percentage of the dry weight of the seeds. The procedure for each sampling was replicated accordingly, and the mean value identified as the actual result. The moisture content for Sample A (white corn) was found to be 31.7%, while that of Sample B (yellow corn) was found to be 21.5%, which shows that the yellow corn would always have longer storage value than the white corn. As any change in the seed moisture content has a way of affecting its storage life, it is advisable not to store the white corn longer than it could be applied in the yellow corn for a better storage value.Keywords: Determination, Moisture Content, White Corn, Yellow Corn, Dry-weight Basis

An improved technique for the determination of rock porosity

1986 ◽  
Vol 23 (8) ◽  
pp. 1068-1074 ◽  
Author(s):  
T. W. Melnyk ◽  
A. M. M. Skeet
Keyword(s):  
Spatial Variation ◽  
Water Immersion ◽  
Dry Weight ◽  
Mean Value ◽  
Modified Technique ◽  
Immersion Method ◽  
The Mean ◽  
Water Saturated ◽  
Improved Technique

A modified technique for the determination of the connected porosity of rocks by the water immersion method has been developed and tested. The technique is recommended for rocks with porosity less than 0.05. The major modifications to the technique include saturation of the sample under vacuum conditions and determination of the water-saturated but surface-dry weight from a drying curve.Porosity measurements on 48 granitic samples showed that the technique is reproducible within a 95% confidence range of ±4% of the mean value. However, the possibility of spatial variation of porosity must be taken into account in assigning uncertainties to the measured values.

Detection of Circulating Tissue Factor and Factor VII in a Normal Population

1996 ◽  
Vol 75 (05) ◽  
pp. 772-777 ◽  
Author(s):  
Sybille Albrecht ◽  
Matthias Kotzsch ◽  
Gabriele Siegert ◽  
Thomas Luther ◽  
Heinz Großmann ◽  
...  
Keyword(s):  
Tissue Factor ◽  
Normal Population ◽  
Mean Value ◽  
Factor Vii ◽  
Significant Difference ◽  
Age Dependent ◽  
The Mean ◽  
Highly Correlated ◽  
And Gender

SummaryThe plasma tissue factor (TF) concentration was correlated to factor VII concentration (FVIIag) and factor VII activity (FVIIc) in 498 healthy volunteers ranging in age from 17 to 64 years. Immunoassays using monoclonal antibodies (mAbs) were developed for the determination of TF and FVIIag in plasma. The mAbs and the test systems were characterized. The mean value of the TF concentration was 172 ± 135 pg/ml. TF showed no age- and gender-related differences. For the total population, FVIIc, determined by a clotting test, was 110 ± 15% and the factor VIlag was 0.77 ± 0.19 μg/ml. FVII activity was significantly increased with age, whereas the concentration demonstrated no correlation to age in this population. FVII concentration is highly correlated with the activity as measured by clotting assay using rabbit thromboplastin. The ratio between FVIIc and FVIIag was not age-dependent, but demonstrated a significant difference between men and women. Between TF and FVII we could not detect a correlation.

Determination of Plasminogen in Clots and Thrombi

1966 ◽  
Vol 16 (01/02) ◽  
pp. 038-050 ◽  
Author(s):  
Ulla Hedner ◽  
Inga Marie Nilsson ◽  
B Robertson
Keyword(s):  
Mean Value ◽  
Main Mechanism ◽  
Clot Lysis ◽  
Post Mortem ◽  
Digestion Time ◽  
Normal Volunteers ◽  
Casein Solution ◽  
The Mean

SummaryThe plasminogen content was determined by a casein method in plasma and serum from 20 normal volunteers. The mean plasminogen content was found to be 10.1 ACU (the arbitrary caseinolytic unit defined in such a way that using a 3% casein solution and a digestion time of 20 min. at 37°C, 10 ACU gave an extinction of 0.300). No difference between serum and plasma regarding the plasminogen content was found.Plasminogen was determined in drained and drained plus washed clots prepared from 2 ml plasma. The highest values found in the drained clots were 0.9 ACU/clot and 0.2 ACU/clot in the drained plus washed clots.Plasminogen was also determined in drained and drained plus washed clots prepared from plasma with added purified plasminogen. The plasminogen was recovered in the washing fluid. According to these tests, then, purified added plasminogen is washed out of the clots.The plasminogen content of 20 thrombi obtained post mortem was also determined. The mean value was found to be 0.7 ACU/cm thrombus. Judging from our results, the “intrinsic clot lysis theory” is not the main mechanism of clot dissolution.

SERUM TRIIODOTHYRONINE DETERMINATION BY SATURATION ANALYSIS

1973 ◽  
Vol 72 (4) ◽  
pp. 714-726 ◽  
Author(s):  
A. Burger ◽  
B. Miller ◽  
C. Sakoloff ◽  
M. B. Vallotton
Keyword(s):  
Ionic Strength ◽  
Limit Of Detection ◽  
Improved Method ◽  
Accuracy Of Measurement ◽  
Tracer Amount ◽  
The Mean ◽  
Physiological Values ◽  
Hyperthyroid Patients ◽  
Solvent Blank

ABSTRACT An improved method for the determination of serum triiodothyronine (T3) has been developed. After addition of a tracer amount of the hormone, T3 was extracted from 1 ml serum under conditions of pH and ionic strength which favoured T3 extraction (89%) over thyroxine (T4) extraction (58%). Chromatography of the extracted material on Sephadex LH-20 separated T3 completely from residual T4. The T3 eluate was dried, then re-dissolved in 0.5 ml NaOH 0.04 n. To 0.2 ml duplicate aliquots, a standard amount of TBG was added for the competitive protein analysis. After one hour incubation at 4°C, separation of bound from free T3 was achieved on small Sephadex G-25 columns. Overall recovery was 67 ± 10.8% and correction for the loss was made. The solvent blank was 37 ± 27 (sd) ng/100 ml. Accuracy of measurement of known quantities of T3 added to serum was 98.4%. The coefficient of variation within the assay was 6.2% and between the assays it was 11.4%. The limit of detection (0.1 ng) corresponded to a concentration of 25 ng/100 ml. T4 added to serum did not interfere with T3 determination until high non-physiological values were reached. The mean ± sd serum T3 in 54 euthyroid subjects was 153 ± 58 ng/100 ml and in 24 hyperthyroid patients it was 428 ±186 ng/100 ml; 4 out of the 24 hyperthyroid values were within 2 sd of the mean euthyroid group. All the values found in the euthyroid group were well above the limit of detection of the method.

BIOASSAY OF PROLACTIN

1969 ◽  
Vol 60 (1) ◽  
pp. 91-100 ◽  
Author(s):  
Charles S. Nicoll
Keyword(s):  
Epithelial Cells ◽  
Lipid Content ◽  
Dry Weight ◽  
Fat Content ◽  
Assay Sensitivity ◽  
Mucosal Epithelium ◽  
Wet Weight ◽  
Total Dry Weight

ABSTRACT The response of the pigeon crop-sac to systemically acting prolactin (injected subcutaneously) was evaluated by measuring the wet weight of the responsive lateral lobes of the organ and by determining the dry weight of a 4 cm diameter disc of mucosal epithelium taken from one hemicrop. Of several different injection schedules tested, administration of prolactin in four daily injections was found to yield optimal responses. When compared with a graded series of prolactin doses, measurement of the mucosal dry weight proved to be a better method of response quantification than determination of the crop-sac wet weight with respect to both assay sensitivity and precision. The submucosal tissue of the crop-sac was estimated to constitute about 64 % of the total dry weight of the unstimulated organ and it was found to be relatively unresponsive to prolactin stimulation in comparison with the mucosa. The lipid content of the mucosal epithelium was determined using unstimulated crop-sacs or tissues which showed varying degrees of prolactin-induced proliferation. The fat content of the mucosal epithelial cells increased only slightly more rapidly than the dry weight or the defatted dry weight of the mucosa. Suggestions are made for the further improvement of the systemic crop-sac assay for prolactin.

Determination of the Probability Distribution of the Mean Sound Level

2010 ◽  
Vol 35 (4) ◽  
pp. 543-550 ◽  
Author(s):  
Wojciech Batko ◽  
Bartosz Przysucha
Keyword(s):  
Probability Distribution ◽  
Probability Distribution Function ◽  
Mean Value ◽  
Sound Level ◽  
Function Form ◽  
Noise Levels ◽  
Logarithmic Mean ◽  
The Mean ◽  
Estimation Of Uncertainty

AbstractAssessment of several noise indicators are determined by the logarithmic mean <img src="/fulltext-image.asp?format=htmlnonpaginated&src=P42524002G141TV8_html\05_paper.gif" alt=""/>, from the sum of independent random resultsL1;L2; : : : ;Lnof the sound level, being under testing. The estimation of uncertainty of such averaging requires knowledge of probability distribution of the function form of their calculations. The developed solution, leading to the recurrent determination of the probability distribution function for the estimation of the mean value of noise levels and its variance, is shown in this paper.

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