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T Dijkstra

Publications and source records attributed to T Dijkstra.

11 recordsLinked to original sources
PubMed1994

[Determination of the excretion time of oxytetracycline and lugol in milk of intrauterine treated cows].

Sixteen dairy cows with chronic puerperal endometritis between 3 and 8 weeks post partum were treated with intra-uterine applied oxytetracycline (OTC) and lugol. OTC was rapidly removed from plasma and was not detectable after 48 hours. The concentration of OTC in milk did not exceed 40 micrograms/kg, and it was still detectable in milk 34 hours after treatment. The concentration of OTC in milk was always lower than the limit of 50 micrograms/kg used by milk-testing stations and the European limit (MRL) of 100 micrograms/kg. Milk from cows treated with lugol did not cause inhibition in the plate test.

Administration, Topical↗
PubMed1993

Bidirectional grapheme-phoneme activation in a bimodal detection task.

A divided attention paradigm was used to investigate whether graphemes and phonemes can mutually activate or inhibit each other during bimodal processing. In 3 experiments, Dutch subjects reacted to visual and auditory targets in single-channel or bimodal stimuli. In some bimodal conditions, the visual and auditory targets were nominally identical or redundant (e.g., visual A and auditory /a/); in others they were not (e.g., visual U and auditory /a/). Temporal aspects of cross-modal activation were examined by varying the stimulus onset asynchrony of visual and auditory stimuli. Cross-modal facilitation--but not inhibition--occurred rapidly and automatically between phoneme and grapheme representations. Implications for current models of bimodal processing and word recognition are discussed.

Adult↗
PubMed1992

[Ascaris suum infection as a cause of clinical problems in cattle?].

A sudden decrease in milk yield, increased respiratory rate and occasional coughing were observed in dairy cows on two farms in spring 1991. Pigs were also kept on these farms, and pastures grazed by the cattle had been fertilised with pig slurry. Laboratory investigations of some of the cattle showed eosinophilia and high ELISA titres of antibodies against Ascaris suum. On one farm the clinical symptoms disappeared after the animals had been treated with oxfendazole and on the other farm the symptoms disappeared spontaneously with time.

Animals↗
PubMed1992

[Cows with swollen anus and vulva as a husbandry problem].

An acute farming problem is described. The symptoms were poor intake of concentrates, swelling of the anus and vulva, and decreased milk production. Research results show that pig premix was incorporated into the concentrate for dairy cows. Which component of the concentrate was responsible for the symptoms remains to be established.

Animal Feed↗
PubMed1990

Lexical effects in phonemic processing: facilitatory or inhibitory.

This article addresses the questions of how and when lexical information influences phoneme identification in a series of phoneme-monitoring experiments in which conflicting predictions of autonomous and interactive models were evaluated. Strong facilitatory lexical effects (reflected by large differences in detection latencies to targets in words and matched nonwords) were found only when targets came after the uniqueness point of the target-bearing word. Furthermore, no evidence was obtained for lexically mediated inhibition on phoneme identification as predicted by the interactive activation model TRACE. These results taken together point to strong limitations in the way in which lexical information can affect the perception of unambiguous speech.

Adult↗
PubMed1986

Interaction between circadian and caloric control of feeding behavior in the rat.

Feeding at the beginning of the night is probably dependent on the rat's immediate energy requirements while feeding at the end may have an anticipatory function. This latter feeding peak may be mainly controlled by a circadian pacemaker. The aim of this study was to investigate the relative contribution of satiety signals and circadian pacemakers in the control of feeding behavior. Food intake was monitored after infusion of liquid food into the stomach during several parts of the day-night cycle to prevent a possible influence of oral sensations. It is demonstrated that intragastric infusion is more effective in suppressing intake during daytime and the first half of the dark phase than during the second half of the dark phase. Suppressions of food intake are mainly due to delaying the first occurrence of food ingestion, whereas the size of that meal is less affected. During the last period of the night no significant delay could be brought about. These experiments suggest that in the rat a circadian pacemaker dominates feeding motivation during the end of the night thereby strongly interacting with caloric control of feeding behavior.

Animals↗
PubMed1985

Acute effects of pentobarbital-anaesthesia on bile secretion.

Male Wistar rats were equipped with permanent catheters in the bile duct and the duodenum under ether anaesthesia, at least seven days before the experiments. By this technique, the enterohepatic circulation can be interrupted for bile collection without direct surgical intervention. 14C-Pentobarbital (26.6 mumole/100 g body wt) was injected intraperitoneally immediately before interruption of the enterohepatic circulation (NBD, Non-Bile Diverted) or after eight days of bile diversion (BD, Bile Diverted). In NBD rats, bile flow and biliary bile acid excretion were significantly reduced during the first hour after pentobarbital administration when compared to unanaesthetized controls, but markedly increased thereafter. Pentobarbital treatment slightly decreased biliary bile acid excretion in BD rats, but caused a 60% increase in bile flow. Within four hours 22.3 +/- 0.4% and 26.0 +/- 2.7% of the injected radioactivity was excreted into bile in NBD and BD rats, respectively. The calculated osmotic activity of pentobarbital and its metabolites was 47.8 +/- 5.2 microliter/mumole in NBD rats and 37.8 +/- 1.3 microliter/mumole in BD rats. Consequently, pentobarbital treatment affected the bile acid independent fraction of bile flow (BAIF). The calculated BAIF was 2.68 microliter/min/100 g body wt in unanaesthetized animals, but 4.27 microliter/min/100 g body wt in pentobarbital treated NBD rats. Corresponding values for BD rats were 1.70 and 2.38 microliter/min/100 g body wt. It is concluded that pentobarbital anaesthesia affects bile production in the rat by direct and indirect means. Firstly, pentobarbital and its metabolites are rapidly excreted into bile and exert a significant choleretic effect, thereby increasing the BAIF. Secondly, pentobarbital anaesthesia retards the exhaustion of the intestinal bile acid pool, which leads to secondary changes in the biliary excretion process.

Anesthesia↗