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K Jensen

Publications and source records attributed to K Jensen.

At least 181 records · Page 10Linked to original sources
PubMed1992

Food aversions: taste reactivity responses elicited by lithium-paired food.

The taste reactivity (TR) test was employed to measure the orofacial, somatic and consummatory CRs elicited by a lithium-paired food. Hungry rats were presented chocolate chips followed immediately by an injection of lithium chloride (CS+ group) or saline (CSc group). During the TR test, the rats' behavioral responses to the chocolate chips were videorecorded. The results demonstrated that rats in the CS+ group did not consume the lithium-paired food, but demonstrated the aversive TR response pattern of chain rubbing, paw treading, and gaping.

Animals↗
PubMed1992

Experimental pain in human temporal muscle induced by hypertonic saline, potassium and acidity.

The study was aimed at developing a reference model for experimental pain and tenderness in the human temporal muscle by the local injection of hypertonic saline, potassium chloride and acidic phosphate buffer, using isotonic saline as control. The design was randomized and double-blind. Twenty healthy subjects had 0.2 ml test solution injected into one temporal muscle and saline into the other. Following each injection, pain was rated on a 10-point ordinal scale and pressure-pain thresholds were measured every minute for 10 min by a pressure algometer. Hypertonic saline (n = 11) and potassium chloride (n = 12) induced significantly more pain than isotonic saline (ANOVA, p less than 0.0001). Compared to control injections, hypertonic saline and potassium chloride induced a significant reduction in pressure-pain threshold (ANOVA, p less than 0.0001 and p less than 0.05). Forty-eight percent of the injections led to the referral of pain most often to the jaws. A positive correlation between the relative occurrence of referred pain and pain intensity was observed (p less than 0.001) as was a negative correlation between the decrease in pressure-pain threshold and pain intensity (p less than 0.05).

Acids↗
PubMed1992

Denitrification, dissimilatory reduction of nitrate to ammonium, and nitrification in a bioturbated estuarine sediment as measured with N and microsensor techniques.

Nitrogen and oxygen transformations were studied in a bioturbated (reworked by animals) estuarine sediment (Norsminde Fjord, Denmark) by using a combination of N isotope (NO(3)), specific inhibitor (C(2)H(2)), and microsensor (N(2)O and O(2)) techniques in a continuous-flow core system. The estuarine water was NO(3) rich (125 to 600 muM), and NO(3) was consistently taken up by the sediment on the four occasions studied. Total NO(3) uptake (3.6 to 34.0 mmol of N m day) corresponded closely to N(2) production (denitrification) during the experimental steady state, which indicated that dissimilatory, as well as assimilatory, NO(3) reduction to NH(4) was insignificant. When C(2)H(2) was applied in the flow system, denitrification measured as N(2)O production was often less (58 to 100%) than the NO(3) uptake because of incomplete inhibition of N(2)O reduction. The NO(3) formed by nitrification and not immediately denitrified but released to the overlying water, uncoupled nitrification, was calculated both from NO(3) dilution and from changes in NO(3) uptake before and after C(2)H(2) addition. These two approaches gave similar results, with rates ranging between 0 and 8.1 mmol of N m day on the four occasions. Attempts to measure total nitrification activity by the difference between NH(4) fluxes before and after C(2)H(2) addition failed because of non-steady-state NH(4) fluxes. The vertical distribution of denitrification and oxygen consumption was studied by use of N(2)O and O(2) microelectrodes. The N(2)O profiles measured during the experimental steady state were often irregularly shaped, and the buildup of N(2)O after C(2)H(2) was added was much too fast to be described by a simple diffusion model. Only bioturbation by a dense population of infauna could explain these observations. This was corroborated by the relationship between diffusive and total fluxes, which showed that only 19 to 36 and 29 to 62% of the total O(2) uptake and denitrification, respectively, were due to diffusion-reaction processes at the regular sediment surface, excluding animal burrows.

Journal Article↗
PubMed1992

A single base deletion in the 5' noncoding region of Theiler's virus attenuates neurovirulence.

Viral chimeras have been constructed through in vitro manipulations of the infectious cDNA clones of two prototypes of Theiler's murine encephalomyelitis virus: (i) the virulent GDVII strain and (ii) the less virulent BeAn and VL strains. Previous studies have suggested that the phenotypic differences in virulence between the BeAn and GDVII strains map to both the 5' noncoding and the coat protein regions of these viral genomes. It is shown here that attenuation mapped to the 5' noncoding region is due, at least in part, to an inadvertent deletion resulting from a cloning artifact of one C nucleotide out of four between positions 876 and 879 in the BeAn sequences. The in vitro growth characteristics in BHK-21 cells, however, do not reflect the large differences in neurovirulence between chimeras that are identical except for the deleted C. Another chimera with a mutation at position 877 and a deletion at 976 is also attenuated. The wild-type sequences from the less virulent strains BeAn and VL between nucleotides 1 and 933, in an otherwise GDVII chimera, do not attenuate virulence. Sequences of the 500 nucleotides of the 5' noncoding region proximal to the translation initiation codon were obtained for nine additional Theiler's virus strains. The attenuating deletions are discussed in the context of these sequences and the proposed secondary structures for the 5' noncoding region.

Animals↗
PubMed1992

Suicide and multiple sclerosis: an epidemiological investigation.

In a nationwide investigation the risk of death by suicide for patients with multiple sclerosis (MS) was assessed using records kept at the Danish Multiple Sclerosis Registry (DMSR) and the Danish National Register of Cause of Death. The investigation covers all MS patients registered with DSMR with an onset of the disease within the period 1953-85, or for whom MS was diagnosed in the same period. Fifty three of the 5525 cases in the onset cohort group committed suicide. Using the figures from the population death statistics by adjustment to number of subjects, duration of observation, sex, age, and calendar year at the start of observation, the expected number of suicides was calculated to be nearly 29. The cumulative lifetime risk of suicide from onset of MS, using an actuarial method of calculation, was 1.95%. The standard mortality ratio (SMR) of suicide in MS was 1.83. It was highest for males and for patients with onset of MS before the age of 30 years and those diagnosed before the age of 40. The SMR was highest within the first five years after diagnosis.

Adaptation, Psychological↗
PubMed1992

MS mortality.

Explore the source record for details and available documents.

Humans↗
PubMed1991

[Cancer and suicide. Review of the literature].

On the basis of the available literature about cancer and suicide, it is concluded that patients with cancer show a moderately increased risk of committing suicide. This risk is greatest during the first year after diagnosis of the disease. The forms of cancer which most frequently involves suicide are cancer in the gastro-intestinal canal in men and cancer of the breast and genitalia in women. Points of view as to how the risk of suicide in these patients may be reduced are presented and discussed.

Adult↗
PubMed1991

Upper extremity function in spina bifida.

Poor upper extremity function is often recorded in meningomyelocele patients. Only 2 of the 25 patients we assessed, 5 to 19 years old, showed normal upper extremity function in the clinical neurological examination and a timed hand function test simulating daily activities. Slow performance with unsystematic variability was typical. Poor hand function correlated strongly with hydrocephalus. A trend towards better performance with increasing age may indicate that the difficulties are overcome in some patients. While patients without hydrocephalus showed a near-normal distribution in the seven subtests, patients with hydrocephalus needed more time than normal children. Patients with shunt-treated hydrocephalus did not cope as well as patients without a shunt. Mean age in the three groups differed and may partly explain the differences.

Adolescent↗
PubMed1991

The effects of indomethacin on intracranial pressure, cerebral blood flow and cerebral metabolism in patients with severe head injury and intracranial hypertension.

In five head-injured patients with cerebral contusion and oedema in whom it was not possible to control intracranial pressure (ICP) (ICP greater than 20 mmHg) by artificial hyperventilation (PaCO2 level 3.5-4.0 kPa) and barbiturate sedation, indomethacin was used as a vasoconstrictor drug. In all patients, indomethacin (a bolus injection of 30 mg, followed by 30 mg/h for seven hours) reduced ICP below 20 mmHg for several hours. Studies of cerebral circulation and metabolism during indomethacin treatment showed a decrease in CBF at 2 h. After 7 h, ICP remained below 20 mmHg in three patients, and these still had reduced CBF. In the other patients a return of ICP and CBF to pretreatment levels was observed. In all patients indomethacin treatment was followed by a fall in rectal temperature. These results suggest that indomethacin due to its cerebral vasoconstrictor and antipyretic effect should be considered as an alternative for treatment of ICP-hypertension in head-injured patients.

Adult↗
PubMed1991

Pain, tenderness, wheal and flare induced by substance-P, bradykinin and 5-hydroxytryptamine in humans.

The algesic effect of substance-P with and without the addition of bradykinin or 5-hydroxytryptamine was studied in 13 healthy volunteers. Test substances dissolved in saline were injected into the temporal muscle and the forearm skin and the effects compared with those of saline. In the temporal muscle, none of the test substances induced more pain than saline, but substance-P with bradykinin lowered the pressure pain threshold by 18% (p less than 0.02). All test substances induced pain wheal and flare in the forearm skin. Substance-P induced a more pronounced flare reaction than bradykinin, whereas the latter induced more pain than substance-P. This dissociation between pain and flare may indicate that C-fibres in the human skin represent more than one type of nociceptor.

Adult↗