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N Davis

Publications and source records attributed to N Davis.

15 recordsLinked to original sources
PubMed1992

Direct association of pp40/I kappa B beta with rel/NF-kappa B transcription factors: role of ankyrin repeats in the inhibition of DNA binding activity.

To understand the mechanism by which pp40/I kappa B beta inhibits DNA binding activity of the rel/NF-kappa B family of transcription factors, we have investigated the role of ankyrin repeats on the biological function of pp40 by deleting or mutating conserved residues. We show that (i) ankyrin repeats alone are not sufficient to manifest biological activity but require the C-terminal region of the pp40 protein; (ii) four out of the five ankyrin repeats are essential for inhibiting the DNA binding activity; (iii) pp40 mutants that do not inhibit DNA binding of rel protein also do not associate with rel; (iv) although pp40 can associate with the p65 and p50 subunits of NF-kappa B, pp40 inhibits the DNA binding activity of only the p50-p65 heterodimer and the p65 homodimer; and (v) pp40 inhibits the transcription of genes linked to kappa B site; however, mutants that do not affect DNA binding have no effect. We propose that the ankyrin repeats and the C-terminal region of pp40 form a structure that associates with the rel homology domain to inhibit DNA binding activity.

Amino Acid Sequence↗
PubMed1992

Role of frozen section and clinical parameters in distinguishing benign from malignant follicular neoplasms of the thyroid.

The determination of malignancy preoperatively or intraoperatively is difficult in patients with follicular neoplasms of the thyroid. This study reviews a series of 395 patients treated for follicular neoplasms at the Vancouver General Hospital and the British Columbia Cancer Agency between the years of 1955 and 1988, 198 of whom had frozen section at the time of surgery. Frozen section was 79% accurate in differentiating follicular adenomas from carcinomas, with a sensitivity of 52% and a specificity of 100%. The positive predictive value of a frozen section showing carcinoma was 100%, and the negative predictive value was 73%. An incorrect diagnosis of a benign lesion was made in 21% of patients in whom the final diagnosis by fixed section was carcinoma. These same statistics were calculated for patients aged greater than 50 years, tumor size greater than 3 cm, and patients with a history of previous neck irradiation, three clinical factors shown in a previous study to be strong prognostic indicators of malignancy. The results were compared with those found by frozen section. The implications of these results in terms of patient management are discussed.

Adenocarcinoma↗
PubMed1979

Take it off.

Explore the source record for details and available documents.

Dental Enamel↗
PubMed1978

Modern concepts of melanoma and its management.

Malignant melanoma can be diagnosed at an early biological stage when relatively simple excisional surgery carries a remarkably good prognosis. For this to happen requires good public education, so that patients are aware of the potential danger of any change in a mole, and good professional education, so that physicians of first contact are alert to the possibility of melanoma in these patients.

Humans↗
PubMed1977

Arousal from sleep: the physiological and subjective effects of a 15 dB(A) reduction in aircraft flyover noise.

The present research was concerned with whether or not a 15 dB(A) reduction in overall noise level would lessen the sleep disturbing properties of jet aircraft flyover noise and, if less disturbing, whether this would be subjectively appreciated by the sleeping individual. The results indicate that a reduction of 15 dB(A) does result in less sleep disruption but only during sleep characterized by fast-wave electroencephalographic activity. During sleep characterized by slow-wave electroencephalographic activity, such a reduction in the sleep-disturbing properties of jet aircraft noise has little effect. Moreover, even when effective during fast-wave sleep, the decreased arousal produced by the lower noise levels is not subjectively appreciated by the individual in terms of his estimate of the quality of his night's sleep. Thus, reducing the overall noise level of jet aircraft flyovers by some 15 dB(A), is, at best, minimally beneficial to sleep.

Adolescent↗
PubMed1975

Large bowel cancer: a retrospective study of 635 cases.

A retrospective survey of 635 cases of large bowel cancer treated at the Princess Alexandra Hospital, Brisbane, from 1956 to 1970 is presented. The age and sex incidence, presentation and pathology are discussed, and a detailed analysis is made of treatment and operative mortality rates. The resectability rate was 72-2%; the operative mortality rate for resectable colonic lesions was 6-6%, and for resectable rectal lesions, 7-3%. There was an operative mortality rate in the presence of acute obstruction of 17-5%. This study forms the basis of a prospective survey presently being undertaken at the Princess Alexandra Hospital.

Adolescent↗
PubMedDate not supplied

Recovery of function after brain damage: the extrinsic stimulus specificity of spared neural traces.

Previous research has demonstrated that while primary visual cortex lesions in rats will disrupt performance of a learned brightness discrimination, the neural traces associated with this discrimination are spared. Moreover, the spared neural traces may, in certain instances, influence the postoperative reinstatement of a brightness discrimination. The present research was designed to determine the generality of this postoperative influence. The results indicate that while the normal rat and the visual decorticate rat may readily transfer learning between discriminations involving different discriminative cues, a visual lesion between two discriminations prevents this transfer. These data are interpreted as indicating that the postoperative influence of a spared neural trace is dependent upon the reoccurrence of specific extrinsic stimulus cues.

Animals↗