Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “experiment”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 559 records · Page 31Linked to original sources
PubMed1996

[Experience with conservative therapy in primary breast cancer: experiences Northern Israel Oncology Center, 1981-1990].

Between 1981 and 1990, 346 patients with primary breast cancer were treated using breast conservation. Mean age was 55 +/- 13 years and median follow-up 53 months. 36.5% were in pathological Stage I, 55% in Stage II, and 4% in Stage III, while 4.5% were in clinical Stages I-II. 60% of the lesions were excised with good margins, 12% with close margins (0.5 cm), 2.5% with macroscopic residuals, 7.5% with microscopic residuals and 18% with margins that could not be determined. Level II lymph node dissection was performed in 334 patients (97%). Adjuvant therapy (combination of chemotherapy and/ or hormones) was given to 223 (64%). Radiotherapy, usually 50-55 Gy tangential photon irradiation to the whole breast, was given to 335 (97%); electron or photon "boost" to the tumor bed was given to 234 (70%); most patients received 20 Gy. Most node-positive patients received 50 Gy to the lymphatic drainage system. A year after completion of radiotherapy cosmetic results were rated as good in 195/212 (92%), moderate in 17/212 (8%), but in none as poor. 5-year actuarial survival was 90% for Stage I and 81% for Stage II disease. 24 (7%) developed breast recurrence, 8 of whom (2%) also had distant metastases; 5 (1.5%) developed supraclavicular lymph node metastases and 59 (17%) distant metastases. Predictors of poor survival or local recurrence were: age under 40 years, premenopausal status, multifocality, and blood/lymph vessel infiltration by tumor cells. The satisfactory level of local control achieved is attributed to the high doses of radiation administered in high-risk lesions (up to 70 Gy total tumor dose).

Actuarial Analysis↗
PubMed1996

Peacetime clinical experience with "fratricide": a veterans hospital experience.

It is very important for those involved in military medicine to understand the difference between fratricide, accidents, and other causes of wounding. The military medical care provider is often considered an authority on wounding. This is usually not the case. The three examples discussed in this paper illustrate some of the basic misconceptions about "friendly fire" and the appropriate use of the term "fratricide."

Accidents↗
PubMedDate not supplied

[Experimenting curing-caring experimenting. Notes to prevent confusion].

Children, as well as adults, can be subjects of clinical trials. An overview of the history and development of clinical experimentation through the main scientific publications is briefly outlined. A chart of children rights is also presented and discussed. Children's rights range from the right of being included in clinical trials to the right of being participants in a research that complies, without being overwhelmed, with formal rules. The maximum respect for the child is assumed if innovative questions are asked and independence and autonomy of judgement of researches are observed.

Adult↗
PubMed1998

Experience with low-dose aspirin as thromboprophylaxis for the Tissuemed porcine aortic bioprosthesis: a survey of five years' experience.

BACKGROUND AND AIMS OF THE STUDY: In patients in sinus rhythm following aortic valve replacement (AVR) with bioprosthetic valves, aspirin prophylaxis generally keeps bleeding complications to a minimum without increasing the risks of thromboembolic events. To study the efficacy of aspirin prophylaxis in patients receiving the recently introduced Tissuemed porcine bioprosthetic implant in the aortic position we reviewed our database of 145 patients who underwent AVR between 1991 and 1996. METHODS: Mean patient age was 73.5 years (range: 56 to 94 years); 85 were males and 60 females. Preoperatively, 70% of the patients were in NYHA functional class III or IV. Concomitant procedures were performed in 26% of patients. Following AVR, low-dose aspirin prophylaxis (75 mg/day) was commenced in all patients in sinus rhythm. The bioprosthesis was evaluated using standard Society of Thoracic Surgery guidelines. RESULTS: Follow up was 100% complete (total cumulative follow up 253.7 patient-years (pt-yr)). There were three minor thromboembolic episodes, all occurring at least one year after surgery; there were no major thromboembolic complications and bleeding events. Valve-related complication rates (expressed as %/pt-yr and number of events) were thromboembolism 0.7%/yr (three episodes), hemorrhage 0.4%/yr (one) and bacterial endocarditis 0.4%/yr (one). The reoperation rate was 0.4%/yr (one). At five years, actuarial freedom from thromboembolism was 95 +/- 3.6% (SE); hemorrhage 99.2 +/- 0.75%; endocarditis 98.4 +/- 1.5); non-structural valve failure 100%; structural valve dysfunction 100% and reoperation 98.4 +/- 1.5%. The 30-day mortality rate in this elderly population, influenced by clinical status (NYHA class III and IV; p = 0.005), was 9.6% (95% CI, 4.8 to 14.4), with no early valve-related deaths. Patient survival at five years was 78.5 +/- 3.7%. At follow up, 94.8% of the patients were in NYHA functional class I or II. CONCLUSIONS: Early clinical evaluation showed that, following AVR, bleeding complications were minimal with no increase in thromboembolic events in the first three months and on long-term follow up, when low-dose aspirin prophylaxis was started in patients in sinus rhythm. There was overall improvement in patient symptoms while valve-related complications were minimal with no episode of structural deterioration or non-structural failure.

Aged↗
PubMed2006

Modulation of aggressive behaviour by fighting experience: mechanisms and contest outcomes.

Experience in aggressive contests often affects behaviour during, and the outcome of, later contests. This review discusses evidence for, variations in, and consequences of such effects. Generally, prior winning experiences increase, and prior losing experiences decrease, the probability of winning in later contests, reflecting modifications of expected fighting ability. We examine differences in the methodologies used to study experience effects, and the relative importance and persistence of winning and losing experiences within and across taxa. We review the voluminous, but somewhat disconnected, literature on the neuroendocrine mechanisms that mediate experience effects. Most studies focus on only one of a number of possible mechanisms without providing a comprehensive view of how these mechanisms are integrated into overt behaviour. More carefully controlled work on the mechanisms underlying experience effects is needed before firm conclusions can be drawn. Behavioural changes during contests that relate to prior experience fall into two general categories. Losing experiences decrease willingness to engage in a contest while winning experiences increase willingness to escalate a contest. As expected from the sequential assessment model of contest behaviour, experiences become less important to outcomes of contests that escalate to physical fighting.A limited number of studies indicate that integration of multiple experiences can influence current contest behaviour. Details of multiple experience integration for any species are virtually unknown. We propose a simple additive model for this integration of multiple experiences into an individual's expected fighting ability. The model accounts for different magnitudes of experience effects and the possible decline in experience effects over time. Predicting contest outcomes based on prior experiences requires an algorithm that translates experience differences into contest outcomes. We propose two general types of model, one based solely on individual differences in integrated multiple experiences and the other based on the probability contests reach the escalated phase. The difference models include four algorithms reflecting possible decision rules that convert the perceived fighting abilities of two rivals into their probabilities of winning. The second type of algorithm focuses on how experience influences the probability that a subsequent contest will escalate and the fact that escalated contests may not be influenced by prior experience. Neither type of algorithm has been systematically investigated.Finally, we review models for the formation of dominance hierarchies that assume that prior experience influences contest outcome. Numerous models have reached varied conclusions depending on which factors examined in this review are included. We know relatively little about the importance of and variation in experience effects in nature and how they influence the dynamics of aggressive interactions in social groups and random assemblages of individuals. Researchers should be very active in this area in the next decade. The role of experience must be integrated with other influences on contest outcome, such as prior residency, to arrive at a more complete picture of variations in contest outcomes. We expect that this integrated view will be important in understanding other types of interactions between individuals, such as mating and predator-prey interactions, that also are affected significantly by prior experiences.

Aggression↗
PubMed1990

Physical contact experience and depression.

Out of a consideration of the relevance of interpersonal physical contact to mental health is developed the hypothesis that unsatisfactory physical contact experience predisposes to depression. This hypothesis is then systematically explored using self-ratings of depression and physical contact (and love) experience obtained on admission and at discharge from 254 unselected psychiatric in-patients. Following the demonstration of a strong association between unsatisfactory physical contact experience and depression a significant relationship is also found between depression and the experience of being not loved. These two relationships are shown to exist independently of one another and when direction of causation is investigated both unsatisfactory physical contact experience and the experience of being not loved are seen to be causal of depression rather than vice versa. Unsatisfactory physical contact experience, however, clearly has the greater utility as an indicator of depression-proneness. Different categories and different kinds of physical contact experience are explored, first in relation to depression generally and then to each of the three major forms of depressive illness. Considered too is the patterning of physical contact experience and love experience for each of these latter. The results suggest that depression generally tends to be more closely linked with stable than unstable unsatisfactory physical contact experience and with present rather than childhood such experience. In addition endogenous depression is seen to be characterised by an absence of any physical contact experience in the present, while manic-depressive psychosis combines unsatisfactory physical contact experience with the experience of being loved and shows a relative lack of exclusively bad physical contact experience in childhood. Reactive depression, however, emerges with no distinguishing features of this kind. There follows an examination of the relationships between unsatisfactory physical contact experience and those psychiatric conditions other than depression represented in the subject sample. This raises the possibility that unsatisfactory physical contact experience could also be closely linked with schizophreniform disorder and adjustment disorder. Finally it is suggested that, above all, physical contact experience may be a major determinant of the capacity to cope with stress. Unsatisfactory such experience might then be predisposing to a wide range of psychiatric disorders, with depression seen as a commonly occurring symptom of inadequate coping.

Adaptation, Psychological↗
PubMed1999

The winner and loser effect: integrating multiple experiences.

An important question in state-dependent behaviour is how multiple influences on state are integrated to determine current behaviour. Aggressive behaviour is known to be affected by a prior contest experience. Nevertheless, whether and how multiple prior fighting experiences are integrated into a fighting decision remain unexplored. In this study, individuals of Rivulus marmoratus (Cyprinodontidae), a hermaphroditic fish, were given different combinations of two prior fighting experiences to investigate: (1) the effect of penultimate experiences on the probability of winning a subsequent contest; (2) the relative effect of a recent win and loss; and (3) whether the effect of a winning experience was as short lived as observed in other species. Penultimate and recent fighting experiences were given to the test fish approximately 48 and 24 h prior to the dyadic contests, respectively. From the results of the five types of contests staged, we conclude that: (1) penultimate fighting experiences had a significant effect on the probability of winning a subsequent contest; (2) a more recent experience had a more pronounced effect than an earlier experience, which suggested that the effect of a fighting experience would decay and/or the effect of a recent experience would interfere with the effect of an earlier experience; (3) no asymmetric effect between a winning experience and a losing experience was detected; and (4) the effect of both a winning and a losing experience lasted for at least 48 h in R. marmoratus which was the maximum time tested in these experiments. The possible reasons for the differences in results among studies of experience effects on contest outcomes are discussed. Copyright 1999 The Association for the Study of Animal Behaviour.

Journal Article↗
PubMed1980

Experience and the development of intelligence in young children at home and in day care.

This study examined the relationship between the antecedent everyday experiences of middle-class children in middle-class day-care centers and their intellectual development assessed by the Binet and tests of Spatial Abilities and Receptive Language at age 3. As in the previous study of children in home care, certain types of experiences were hypothesized in advance to be intellectually valuable in that they seemed to provide the clearest opportunities for the child to learn the skills required for successful test performance. The study demonstrated that these experiences were indeed uniquely intellectually valuable in that (apart from preparatory, planful activities) they comprised the only category of everyday experiences that predicted test scores. The research then compared the predictive power of various combinations of sources and topics of intellectual experiences. As expected from the home-care results, language-mastery experiences provided by caregivers when the child was 18--33 months old were clearly the most valuable type of intellectual experiences in predicting test scores at age 3. This subset of intellectual experiences stood out as the strongest predictor of IQ in day care. Performance on the Spatial Abilities and Receptive Language tests was also significantly predicted by language-mastery experiences but here, in contrast to IQ, other types of interactive experiences in which the child played a more prominent role vis-à-vis the caregiver and also experiences which focused on the acquisition of skills other than language were beneficial. The critical importance of intellectually stimulating interaction with caregivers was highlighted by the finding that, of the six combinations of sources and topics of intellectual experiences that proved predictive of test scores, four referred to experiences occurring in interactive situations in which the child are caregiver jointly created the intellectual experiences or in which the caregiver unilaterally structured the experiences for the child. By comparison, intellectual experiences that the child generated for himself in solitary play explained little of the variance in test performance. In sum, this study strongly suggested that, by reciprocally or unilaterally providing various forms of intellectual stimulation and especially experiences designed to foster the mastery of language, caregivers may play a essential, --at least insofar as the 3-year-old's intellectual competence is validly assessed by measures like IQ. Why teachers provided more of this stimulation to some children than others was not clear. Their differential treatment seems to have been guided in part by perceptions of individual intellectual development and especially language competence, but, as in the home-care study, their behavior also seems to have been affected by many other unmeasured factors.

Child Day Care Centers↗
PubMed1988

Effect of sire and sexual experience on serving capacity of yearling beef bulls.

Two experiments were conducted in successive years on a Kansas ranch to determine 1) if serving capacity could be evaluated in virgin yearling beef bulls under field conditions, 2) the influence of sire on serving capacity, and 3) the effect of sexual experience on subsequent serving capacity for low serving capacity bulls. In Experiments 1 and 2, 70 and 78 Angus bulls 13 to 15 mo old representing four and six different sires, respectively, were used. In both experiments, a pretest session that measured reaction time to service preceded two successive serving capacity tests. Following the first serving capacity test, in Experiment 2, all low serving capacity bulls (n = 23) underwent sexual experience school, which consisted of exposure to nonrestrained estrus-induced females over a 4-d period. Five days after sexual experience school (9 d after the first serving capacity test), all Experiment 2 bulls were retested. In both experiments, sire influenced mean serving capacity scores of sons (P < 0.01, Experiment 1; P < 0.05, Experiment 2). Characteristics measured, including age, weight, scrotal circumference, and reaction time, were all unrelated to bulls serving capacity in both experiments, as well as to breeding soudness examination scores for bulls in Experiment 1. There was a dramatic impact of sexual experience school on subsequent serving capacity, since 85% of sexual experience school bulls moved into the medium or high serving capacity category at the second serving capacity test. It is concluded that serving capacity can successfully be evaluated in yearling beef bulls under field conditions, that sire has a profound impact on bulls serving capacity, and that providing sexual experience to low serving capacity bulls can improve their serving capacity.

Journal Article↗