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At least 1,351 records · Page 75Linked to original sources
PubMed1993

[Content of radioactive cesium in selected food products. Radioactive cesium in daily food rations of selected population groups].

The content of radioactive caesium isotopes emitting beta radiation was studied in daily food rations analysed in diets of working-class and non-working-class families from food products from the regions of Olsztyn, Poznań, Lublin, Warsaw and Wrocław in 1987 and 1988. In 1987 the highest level of radioactive caesium was found in the food rations in Olsztyn, and the lowest in the rations in Poznań (3.32 and 0.65 Bq/kg respectively). In 1988 higher radio-caesium content was found in rations composed according to the data on the diet consumed daily in non-working-class families. In that case the highest content was in the daily food ration composed in Warsaw--2.35 Bq/kg, and lowest in Poznań--1.19 Bq/kg. In the daily food rations of working-class families about one half of that value was found. The calculated mean values of both analysed rations were: 1.35 for Olsztyn, 0.89 for Poznań, and 1.86 Bq/kg for Warsaw. The calculated mean value of the contamination with radioactive caesium was in 1988 0.93 Bq/kg for the rations in working-class families (in 1987 it was 1.80 Bq/kg).

Cesium Radioisotopes↗
PubMed1993

Arthroscopic debridement and decompression for selected rotator cuff tears. Clinical results, pathomechanics, and patient selection based on biomechanical parameters.

Clinical results of arthroscopic rotator cuff debridement and decompression in 25 patients are presented. Additionally, a fluoroscopic study of 14 patients with known massive rotator cuff tears reveals four kinematic patterns in patients with major cuff deficiencies. Biomechanical models are used to support further the clinical impression that certain rotator cuff tears are amenable to arthroscopic debridement and decompression without repair. Specific indications for arthroscopic debridement and decompression are developed and presented.

Aged↗
PubMed1998

[Determination of selected mycotoxins in food. I. Selection of optimal conditions for the determination of aflatoxin M1 in milk using high-performance liquid chromatography methods].

The aim of this study was to perform a optimized method for determination of aflatoxin M1 in milk. The manner of extraction and clean-up of milk extracts as well conditions of reaction of aflatoxin M1 with TFA and HPLC was described. The main steps of optimized method were: extraction of samples with chloroform, clean-up of extracts on SPE C18 columns and by means of extraction with n-hexane, derivatisation of aflatoxin M1 with TFA (60 degrees C, 6 minutes) to acetal form--aflatoxin M2a and determination of aflatoxin by means of the RP-HPLC technique. The mobile phase was a mixture of methanol, isopropanol and water (18 + 7 + 75). Fluorometric detection was made at 370/418-700 nm. The mean recovery of aflatoxin M1 dependent on fortification level was 62-67%, limit of detection was 0.01 microgram/1 of milk.

Aflatoxin M1↗
PubMed1998

[Determination of selected mycotoxins in food. II. Selection of optimal conditions for the determination of fumonisin B1 and B2 in corn products using high performance liquid chromatography].

The aim of this study was to perform a optimised method for determination of fumonisins B1 and B2 in corn products. The manner of extraction and clean-up of corn products extracts as well conditions of reaction of fumonisins with OPA was described. The main steps of optimised analytical procedure were: extraction of sample with methanol and water (3 + 1), clean-up of extracts on SAX column, derivatisation with OPA, and determination by means of RP-HPLC. The mobile phase was a mixture of methanol, water and acetic acid (75 + 24 + 1). Fluorometric detection was made at 370/440 nm. The mean recovery of fumonisins dependent on fortification level and product was 64-95%, limit of detection for each of fumonisins was 15 micrograms/kg.

Carboxylic Acids↗
PubMed1999

Selection for anthelmintic resistance by macrocyclic lactones in Haemonchus contortus.

Two morphologically marked strains of Haemonchus contortus, CAVRS (smooth-macrocyclic lactone resistant) and McMaster (linguiform-macrocyclic lactone susceptible), were used to investigate the selection for anthelmintic resistance following exposure to ivermectin (IVM), a non-persistent anthelmintic. and a more persistent anthelmintic, oral moxidectin (MOX). Three types of selection were investigated: (1) selection of resident worms at the time of treatment (Head selection); (2) selection of incoming-larvae post-treatment (Tail selection); and (3) selection of both resident population and incoming larvae (Head + Tail selection). The experimental animals were adult sheep and lambs. In the controls where there was no anthelmintic selection, the proportion of CAVRS in the adult worm population was the same as the proportion in larvae given to both adults and lambs indicating that CAVRS and McMaster H. contortus were equally infective. There was a significant effect of anthelmintic on total worm numbers in adult sheep with MOX treated adults having less worms, but selection type was non-significant. Anthelmintic type had a significant effect on numbers of resistant worms in adult sheep with less resistant worms in the MOX treated groups, but selection type had no effect. Analysis of variance of arcsine-transformed proportions of resistant worms found that the type of anthelmintic had a highly significant effect, with MOX treated adults having a higher proportion of resistant worms, while type of selection was not significant. In the lambs, nil treated controls and IVM Head + Tail and Tail selected groups had similar geometric mean total worm burdens while Head selected had less total worms. In the MOX treated lamb groups the worm burdens were similar within selection type but less than the IVM treated groups. In the lambs, the types of selection that resulted in more resistant worms were IVM Tail, MOX Head + Tail and MOX Tail. Resistant worm numbers were similar in both adult and lamb groups with Head selection by either MOX or IVM. Moxidectin selected out higher proportions of resistant worms than did IVM in the lambs, with Tail and Head + Tail being stronger selectors than Head. Computer simulations were used to estimate the rate at which resistance developed in the field using the information generated in the present study. The anthelmintic treatments used in the simulation followed a strategic parasite control program for H. contortus in which all sheep receive three Closantel (CLS) treatments in summer. all sheep receive a broad-spectrum (BS) drench or capsule at weaning and lambs receive an additional two BS drenches insummer or no further treatment in the case of the capsule. Moxidectin, IVM-capsule and IVM were the broad spectrum anthelmintics simulated. All simulations were run four times assuming high or low efficacy against resident resistant worms and in the presence or absence of CLS resistance. The simulations indicated that the presence of CLS resistance hastened selection for macrocyclic lactone (ML) resistance. While the IVM-capsule will select most rapidly for ML resistance, IVM oral is expected to be least selective. Moxidectin treatment is intermediate, except in simulations with no CLS resistance and when MOX is assumed to be highly effective against resident ML-resistant worms, in which case MOX can be expected to select more slowly than IVM oral treatments.

Animals↗
PubMed1993

Relationships between color, shape, and pattern selectivities of neurons in the inferior temporal cortex of the monkey.

1. To examine the way in which information from different visual submodalities is integrated in the inferior temporal (IT) cortex of the monkey, we studied the relationships between the color, shape, and pattern selectivities of individual neurons in IT cortex of two awake macque monkeys. Neurons were recorded while each animal performed a visual fixation task. For each neuron, we analyzed selectivity for the visual submodalities of color, contour shape, and textural pattern using preselected standard sets of visual stimuli, namely colored geometrical shapes with certain patterns. 2. About two thirds (62%) of single neurons whose activities were recorded from the anterior part of IT cortex, which included the ventral bank of the superior temporal sulcus, responded to one or more of the stimuli in the standard sets of stimuli used. An index (stimulus selectivity index) was calculated for each neuron to quantify how well a cell discriminated the preferred stimulus from the least preferred stimulus in each set of stimuli. The stimulus selectivity index, as well as the statistical significance of the variation in the responses to the stimuli within a given set, was used to classify a cell as selective or not selective in a given submodality. Of the neurons whose responses were analyzed quantitatively, 69% were selective for color, 68% were selective for shape, and 82% were selective for pattern. 3. Of the neurons that were tested with respect to the selectivity for color and for shape, 45% were selective both for color and shape, 50% were selective for either color or shape, and only 5% were not selective for color or shape. These frequencies were not significantly different from those predicted from the occurrence of the selective and nonselective neurons in each submodality if the independence of the selectivities for color and shape is assumed. We also found that the color preference of individual neurons does not depend on the shape of the stimulus. These results indicate that there was no overt interaction between the selectivities for color and shape in these IT neurons. 4. Of the neurons that were compared with respect to the selectivity for color and for pattern, 58% were selective both for color and pattern, 38% were selective for either color or pattern, and only 4% were not selective for color or pattern. There was no correlation between the degree of color selectivity and the degree of pattern selectivity of individual neurons.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗