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K O'Connor

Publications and source records attributed to K O'Connor.

At least 55 records · Page 3Linked to original sources
PubMed1994

Nutrition and the variation in level and age patterns of mortality.

We examine the associations between nutrition and mortality at the national level. Altogether four aspects of this association are explored: (1) total calories with expectation of life, (2) dietary composition with expectation of life, (3) total calories with the age patterns of mortality, and (4) dietary composition with the age patterns of mortality. The data consist of life tables and national food balance sheets for 341 populations from 96 countries. A preliminary principal components analysis conducted on the dietary composition data yields three dietary components: (1) the overall quality and quantity of the diet, (2) the relative contribution of carbohydrates versus fats, and (3) the relative contribution of fats versus proteins. The results indicate that expectation of life at birth increases with total calories, with overall quality and quantity of the diet, and with the ratio of fats to proteins. The ratio of carbohydrates to fats is negatively associated with level of mortality. However, evidence indicates that the main effect of the ratio of fats to proteins is reversed when diets are high in quality and that all the effects tend to saturate at high nutrient availability. Variation in nutrition is also strongly associated with the international variation in age patterns of mortality. For example, when expectation of life is held constant, populations with higher quality diets tend to have lower childhood mortality and higher adult mortality. The results indicate that nutritional patterns are highly correlated with much of the worldwide variation in mortality and may be a useful criterion for selecting or predicting the best suited model life table for use on a particular population.

Adolescent↗
PubMed1993

Functional lateralization for auditory temporal processing in male and female rats.

In 3 studies adult male rats showed significantly better discrimination of tone sequences with the right ear than with the left ear. This result parallels similar findings of left-hemisphere specialization for auditory temporal processing in humans and nonhuman primates. Furthermore, because clinical evidence supports a link between specialization of the left hemisphere for auditory temporal processing and for speech processing, these results may reflect evolutionary precursors to left-hemisphere language specialization. Because male rats showed a stronger ear advantage than female rats, the findings may relate to evidence of a stronger right ear advantage in men than in women. Finally, results suggest that neonatal handling enhances lateralization for auditory temporal processing in both sexes. Combined results implicate neuroendocrine mechanisms as important factors in the development of lateralization for auditory temporal processing.

Animals↗
PubMed1993

The utility of self-concept as a predictor of recidivism among juvenile offenders.

Forty institutionalized male juvenile offenders in the United States were administered a Role Construct Repertory Grid (Kelly, 1955) and the Self-Consciousness Scale (Fenigstein, Scheier, & Buss, 1975) to determine whether frequent offenders could be differentiated from infrequent offenders on the basis of these instruments. We hypothesized that the frequent offenders would have more "delinquent" self-concepts than the infrequent offenders. The results did not confirm this hypothesis. In fact, the frequent offender group actually had fewer delinquent self-concepts than the offender group, although the trend was not statistically significant. This finding is interpreted as an indication that some offenders who acknowledge their delinquent orientation are better able to apply their personal resources toward control of their behavior.

Adolescent↗
PubMed1993

Situational typing and graded smoking reduction.

Twenty-seven smokers were classified pretreatment according to whether they reported high craving to smoke when they were actively engaged (n = 14) in a task or not (n = 13). Both groups reported reduced smoking and craving during a situation-based reduction program. But the former group showed a more consistent increase in self-efficacy, positive change in mood, and reported less relapse at six-month follow-up. We conclude that in our sample, situation-based reduction suited those with a preference to smoke during more goal-directed activities.

Adult↗
PubMed1992

Evaluation of the small intestine by enteroclysis for Crohn's disease.

We reviewed the records of 100 consecutive patients referred for enteroclysis by gastroenterologists because of suspected Crohn's disease of the small bowel to assess the clinical utility of the information obtained by this method. More than one-third of the patients in the study group had subtle lesions of early Crohn's disease, all patients who required surgery had severe disease by radiologic criteria, and none of the 34 patients clinically suspected of having Crohn's disease of the small bowel in whom the enteroclysis was normal developed Crohn's disease in two or more years of clinical follow-up. Enteroclysis provides gastroenterologists with accurate and detailed structural information relevant to the appropriate management of the disease and in our hands is a reliable test for excluding Crohn's disease of the small bowel.

Adolescent↗
PubMed1991

Sequence and analysis of a portion of the genomes of Shope fibroma virus and malignant rabbit fibroma virus that is important for viral replication in lymphocytes.

The 10.7-kb BamHI "C" restriction fragment of malignant rabbit fibroma virus (MV) contains genes that are important for its immunosuppressive activity. When this fragment is transferred to a related avirulent leporipoxvirus, Shope fibroma virus (SFV), recombinant viruses show clinical features characteristic of MV: they replicate in lymphocytes and alter immune function in vitro, induce disseminated tumors in recipient rabbits, and are immunosuppressive in vivo. The 10.7-kb BamHI "C" restriction fragment of MV was sequenced in its entirety. Its DNA sequence and the 14 ORF's derived from analyzing this sequence are discussed. Analysis of known open reading frames to which the ORF's from MV's Bam "C" fragment show homology permits us to identify some MV ORF's showing high degrees of similarity to known and postulated proteins produced by vaccinia virus. Functions for some of these vaccinia proteins are known, while functions for others are hypothetical or unknown. Further analysis of genetic determinants of MV's virulence has indicated that two overlapping restriction subfragments of the BamHI "C" fragment can transfer MV's virulent behavior to SFV. The 0.7-kb region in which these two subfragments overlap includes the C-terminus of MV orf C-7 and the N terminus of MV orf C-8. These correspond to the C- and N-termini, respectively, of SFV orf's D-9 and D-10 and to vaccinia orf's D-6 (early transcription factor) and D-7 (subunit of RNA polymerase). We sequenced the region of SFV's BamHI "D" fragment in this area and illustrate here the comparative sequences of this portion of SFV's genome and orf's. On the basis of comparisons between MV, SFV, and vaccinia in this area we discuss the potential significance of these observations.

Amino Acid Sequence↗
PubMed1991

Echoic memory in the rat: effects of inspection time, retention interval, and the spectral composition of masking noise.

Memory for tones (1100 vs. 2330 Hz) was studied in 4 rats (Rattus norvegicus), as affected by the durations of both target tones (30 to 620 ms) and noise-filled retention intervals (0 to 480 ms). With a 0-ms delay, performance was near asymptotic with the 30-ms tone, but the memory of this brief tone suffered a massive decrement at retention intervals as brief as 60 ms; in contrast, memory for the 340-ms tone was stable for at least 240 ms. If the retention interval was filled by band-stop noise (with targets presented in the spectral gap), then the rat's memory for brief tones was superior to that obtained with the standard broad-band noise filler, and band-stop noise was better than a band-pass noise that had the tones embedded in the region of its spectral energy. These findings are consistent with the hypotheses that auditory memory in the rat consists of a transient sensorylike echoic store and a short-term store more resistant to the effects of retroactive interference.

Animals↗
PubMed1991

Temporal resolution of gaps in noise by the rat is lost with functional decortication.

In Experiment 1 (n = 8), the rat's ability to detect brief gaps in white noise was measured by gap-produced inhibition of an acoustic startle reflex, elicited 100 ms after the gap. After bilateral application of KCl to the cortex, gaps as long as 15 ms provided no reflex inhibition; in contrast, the inhibitory threshold was between 2 and 4 ms in the saline control condition. In Experiment 2 (n = 13), noise pulses of 40, 50, or 70 dB were presented 20-500 ms before the startle stimulus, and in Experiment 3 (n = 5) noise offsets occurred so that the startle stimulus was presented at the end of a 2-30-ms gap. Noise pulses and offsets both inhibited reflex expression equally in saline- and KCl-treated animals. Differences between the normal (saline) functions of noise offsets and gaps suggest additional sensory processing with the longer lead time. The loss of gap sensitivity after KCl application indicates that gap processing, unlike pulses and offsets, depends on cortical mechanisms.

Animals↗
PubMed1991

Electrophrenic ventilation: a different perspective.

Since 1972, radio-frequency electrophrenic nerve pacing (EPP) has been an option for assisting the ventilation of patients with chronic paralytic respiratory insufficiency. Most of the medical literature has been favorable regarding its continued application. We reviewed the literature to determine how "successful" application of EPP was defined. Our studies indicated that long-term follow-up of EPP patients has been generally inadequate with little emphasis placed on incidence and severity of complications. There was no standardization in defining successful experiences with EPP. Upper airway instability during pacing, lack of internal pacemaker alarms, and the risk of sudden pacemaker failure necessitate permanent tracheostomy in the great majority of patients but complications of the presence of a tracheostomy were not considered in evaluating the desirability of EPP. Some EPP patients became independent of any ventilatory support thus benefiting minimally from the time commitment, effort, and extreme expense needed for EPP placement and training. We conclude that EPP is a valid option for the properly screened patient but that expense, failure rate, morbidity and mortality remain excessive and that alternative methods of ventilatory support should be explored.

Diaphragm↗
PubMed1991

Cancer symptom management in the elderly.

Clear and concise written guidelines must designate accountability for coordination of the persons involved. As might be assumed by the preceding discussion, the process takes considerable time and effort. The development of clear guidelines is a long term venture and usually does not occur quickly. In some cases a nearby agency may have developed a useful protocol that when shared with area providers, is quickly accepted. However, one to two years is not uncommon to developing a complex plan of care or protocol which can be used effectively and is specific to the conditions in a particular setting. Written guides, when developed correctly, should save all providers' time, and ensure better client care. Clear directions regarding the care to be provided and well-established lines of communication can save health care providers time and increase the likelihood of better health outcomes for the client. The coordination of planning within the home care agency, and across professional, agency and geographic boundaries is a prerequisite for successful cancer symptom management. The central aim in planning is to enhance the family's ability to manage independently and to facilitate continuity of care in the use of health care services. For the client to have the greatest potential for symptom amelioration, the home care agency must assume a major role in the coordination of care providers in the delivery of care.

Aged↗
PubMed1991

Risky business: HMOs and managed care.

Are HMOs doing all they can do to control health care costs? Or are they enjoying the best of both worlds; that is, healthy subscribers and "equal dollars"?

Cost Control↗
PubMed1991

Electronic claims: still buyer beware?

Information obtained from electronic claims systems can help employers make good decisions. But with all the different packages out there, how will employers know which ones are best for them?

Computer Communication Networks↗