Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “application count”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

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

At least 37 records · Page 2Linked to original sources
PubMed1979

Sperm count depression in pesticide applicators exposed to dibromochloropropane.

Male pesticide applicators who worked with the nematocide dibromochloropropane (DBCP) were examined to determine the possible testicular toxicity from this exposure. Infertility and azoospermia which were first noted among factory workers exposed to DBCP were not observed among the applicators. Sperm count depression, however, was associated with the duration of exposure in the current year but not with exposure in past years. The extent of exposure to DBCP in the current year was also associated with an elevation of serum follicle stimulating hormone (FSH) but not of luteinizing hormone (LH). Sperm count depression was limited to applicators involved in irrigation setup work and in the calibration of equipment. These results suggest that the testicular toxicity of DBCP for men may occur in a shorter period than was previously reported, that the effect may be reversible in men with mild sperm count depression, and that public health measures might be directed at controlling specific application techniques.

Antinematodal Agents↗
PubMed1981

Measurement of specific multiplication of an oncolytic and a nononcolytic strain of Clostridium butyricum inside the tumour UVT 15264 of the mouse.

Clostridium butyricum was recultivated from tumour material after treatment of tumour-bearing mice with spores and counted by soft agar colony technique. The oncolytic strain Cl. butyricum H8 grows inside the tumour UVT 15264 up to 8 X 10(8)/g during 48 h. In this time part of tumour became lysed. Multiplication inside of this tumour by the tumour specific but nononcolytic strain Cl. butyricum CNRZ 528 could not be detected by application counting technique. Combination of spore treatment with antibiotic chemotherapy in dosage able to prevent oncolysis or in dosage to reduce them corresponds with loss of clostridial multiplication or with reduced vegetative multiplication respectively.

Animals↗
PubMed1993

Point counting on the Macintosh. A semiautomated image analysis technique.

In image analysis, point counting is used to estimate three-dimensional quantitative parameters from sets of measurements made on two-dimensional images. Point counting is normally conducted either by hand only or manually through a planimeter. We developed a semiautomated, Macintosh-based method of point counting. This technique could be useful for any point counting application in which the image can be digitized. We utilized this technique to demonstrate increased vacuolation in white matter tracts of rat brains, but it could be used on many other types of tissue. Volume fractions of vacuoles within the corpus callosum of rat brains were determined by analyzing images of histologic sections. A stereologic grid was constructed using the Claris MacDraw II software. The grid was modified for optimum line density and size in Adobe Photoshop, electronically superimposed onto the images and sampled using version 1.37 of NIH Image public domain software. This technique was further automated by the creation of a macro (small program) to create the grid, overlay the grid on a predetermined image, threshold the objects of interest and count thresholded objects at intersections of the grid lines. This method is expected to significantly reduce the amount of time required to conduct point counting and to improve the consistency of counts.

Animals↗
PubMed1983

A simple method for counting adherent cells: application to cultured human monocytes, macrophages and multinucleated giant cells.

A simple method was devised for counting small numbers (10(4)-10(6)) of adherent mononuclear phagocytes, including populations containing multinucleated giant cells, which often arise during cultivation of human blood monocytes. Coverslips with adherent cells were transferred into small volumes (50-200 microliters) of 0.1 M citric acid, pH 2.2, containing 0.05% naphthol blue black and 1.0% of either Triton X-100 or Cetavlon. Triton X-100 was adequate for use with monocytes and macrophages from early cultures. However, Cetavlon was preferable for use with older cultures of adherent human mononuclear cells in order to prevent aggregation of the nuclei from giant cells. When multinucleated cells were present, separately stained coverslips were inspected to determine the mean number of nuclei per cell. This value, together with the number of nuclei per coverslip, permitted calculation of the number of cells per coverslip. The latter value is not readily derived from measurements of protein or DNA content in populations containing multinucleated giant cells. This counting method was simpler and more sensitive than several previously reported methods for enumerating adherent macrophages.

Cell Adhesion↗
PubMedDate not supplied

The super PET 3000-E: a PET scanner designed for high count rate cardiac applications.

OBJECTIVE: Mathematical models for the delineation of regional myocardial perfusion and metabolism with PET require faithful reconstruction of arterial and myocardial time-activity curves following administration of radiotracers. High temporal resolution is often required in such measurements. Many commercially available tomographs exhibit long dead times that limit their count rate capabilities. To overcome these limitations, we developed and tested a whole-body tomographic device (Super PET 3000-E) with high count rate capabilities. The use of cesium fluoride scintillation detectors coupled with a one-to-one detector photomultiplier configuration reduces the system resolving and dead times. MATERIALS AND METHODS: The Super PET 3000-E was subjected to a series of tests with phantoms to determine its resolution, sensitivity, linearity, count rate capabilities, dead time, and random coincidence contribution. RESULTS: The system sensitivity is 136 kcounts/s/microCi/ml and its transverse and longitudinal resolutions are 8.5 and 10.5 mm full width at half-maximum, respectively. The system can easily record a total event rate of 2.0 Mcounts/s with minimal dead time loss and excellent linearity. CONCLUSION: The system fulfills its design goals and allows the very high count rate performance needed for the application of the physiological models used in our cardiac studies.

Algorithms↗
PubMed1998

Radiostrontium analytical method using crown-ether compound and Cerenkov counting and its applications in environmental monitoring.

The radiostrontium content in environmental samples was determined by chemical analysis by means of the fuming nitric acid method and ion exchange method with low-level beta counting and the newly developed method using crown-ether compound. Counting was performed with a low-background counter and a liquid scintillation counter together; the latter was the Cerenkov counting method. All results obtained by these three methods were in good agreement. The time for chemical separation of radiostrontium, using crown-ether compound, is much faster than fuming nitric acid and ion exchange methods. However, due to the high background of the liquid scintillation counter, the detection limit for Cerenkov counting is about two times higher than that for low-background counting.

Chromatography, Ion Exchange↗
PubMed1977

[Liquid scintillation counting of 51chromium. Application to a micromethod of cell-mediated cytotoxic assay (author's transl)].

Detection of gamma emitting isotopes is achieved conventionally by using a gamma spectrometer, or in some cases by liquid scintillation counting. We applied these two methods to the detection of 51 Chromium released in a lymphocyte-mediated cytotoxic reaction. Detection in liquid scintillation appeared more efficient than conventional gamma detection: 16.74% vs 1,11%. It is therefore possible to reduce by a factor of 10 the number of target cells in the cytotoxic assay if liquid scintillation counting is used. Either method gave the same results when applied on the same samples. Liquid scintillation counting is to be preferred when high sensitivity is needed. In addition it offers the advantage of using the same apparatus for detection of gamma or beta emitting isotopes.

Chromium Radioisotopes↗
PubMed2001

Multiple scattering in a reflecting cavity: application to fish counting in a tank.

Classical fisheries acoustics techniques are useless in the presence of multiple scattering or reflecting boundaries. A general technique is developed that provides the number and the scattering strength of scatterers in motion placed inside a highly reflecting cavity. This approach is based on multiple scattering theory. The idea is to measure the average effect of the scatterers on the acoustic echoes of the cavity interfaces. This leads to the measure of the scattering mean free path, a typical length that characterizes the scattering strength of the cloud of scatterers. Numerical results are shown to agree with a simple theoretical analysis. Experiments are performed with fish in a tank at two different scales: ultrasonic frequency (400 kHz) in a 1.4-l beaker with 1-cm-long fish as well as fisheries acoustics frequency (12.8 kHz) in a 30-m3 tank with 35-cm-long fish. These results have interesting applications to fish target strength measurement and fish counting in aquaculture.

Animals↗
PubMed1992

Semiautomatic quantification of silver-stained nucleolar organizer regions in tissue sections and cellular smears.

Silver staining of nucleoli reveals argyrophilic proteins associated with nucleolar organizer region (Ag-NOR) proteins. Argyrophilic components appear as dots about 1 micron in diameter dispersed throughout the nucleolus (Ag-NOR dots). The count of Ag-NOR dots is a useful index for improving the cancer diagnosis and determination of prognosis. Here we describe software developed on a medium-cost image analyzer in order to evaluate the mean area of NORs and their number relative to an internal reference, the number and areas of clusters of NORs and the area of the nucleus. Statistical analysis of the data was performed during counting. The first application concerned counting NOR dots during mitosis in cell imprints; those counts were 2.3, 15.3 and 55.56 for the metaphase, telophase and interphase, respectively (relative to unitary dots of metaphase cells). In the second application we demonstrated a significant difference in NOR numbers between two groups of prostatic cancers with good and poor prognoses (6.05 +/- 2.79 SD and 7.96 +/- 3.01, respectively; with Student's t test, = 1.999; P = .05).

Animals↗
PubMedDate not supplied

Absolute radioassay of extended sources: an equivalent point-source coincidence-counting approach with application to the thyroid.

A general methodology is provided for the absolute assay of radioisotopes decaying with coincident photons in an extended source. In the determination of the source activity, the method requires neither the detailed consideration of the geometric and self-attenuation processes taking place between the source component points nor a knowledge of the distribution of activity across the source. It derives from the concept of the "equivalent point source," that is a fictitious point source whose activity would equal that measured for the actual extended source. It has been developed for an arbitrary number of coincident photon types displaying an arbitrary degree of mutual correlation, and for arbitrary detection geometry. A unifying formalism is developed for both point and extended sources and for single and dual detecting systems. It is found that in all cases the various instrumental and spectroscopic uncertainties appear within a composite parameter (herein called F factor) that can be determined by standard calibration procedures; this factor is in turn only weakly dependent on its own component parameters. New expressions and relationships are obtained that provide a greater physical insight into coincidence-counting methods.

Humans↗