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At least 73 records · Page 4Linked to original sources
PubMed1983

From experiment to experience: side effects of nonsteroidal anti-inflammatory drugs.

As part of the approval process, new drugs are first studied in controlled clinical trials with carefully selected patients. After gaining approval, however, these drugs are often used in the general community under widely different circumstances. This report explores the effects of such differences on the frequency and severity of side effects using the nonsteroidal anti-inflammatory drugs as a prototype. A review of clinical trials is compared with the accumulated experience at the Stanford and Phoenix Arthritis Centers. Statistical analysis of patient records was accomplished using the American Rheumatism Association Medical Information System Computer Data-Base System. To overcome potential biases in different methods of detecting side effects, a questionnaire was mailed directly to 390 patients, including subjects who were and were not participants in formal drug studies. Agreement between experiment and experience was generally quite good. However, a tendency for severe side effects to occur more frequently in community use than would be predicted from clinical trials was noted.

Anti-Inflammatory Agents↗
PubMed1996

Experience with generally accepted centrifugal pumps: personal and collective experience.

BACKGROUND: The data presented are a brief summary of The International Registry for Mechanical Ventricular Assist Pumps and Artificial Hearts and a summary of the personal experience of the Minnesota Thoracic Associates at the Minneapolis Heart Institute with the use of the Sams centrifugal pump from May 1985 to September 1994. METHODS: Ventricular support with the use of centrifugal pumps for postcardiotomy shock consisted of cannulation of the left atrium and aorta for left ventricular support and the right atrium and pulmonary artery for right ventricular support, or the combination of the two for biventricular support. RESULTS: The average survival and discharge rate recorded by the National Registry for postcardiotomy syndrome was 25.3%. Our experience at Minnesota Thoracic Associates was 54%. The National Registry reported 45.7% of the patients being weaned from the device or receiving transplants and 25.3% of the patients ultimately discharged from the hospital. Sixty-five percent of the patients in our experience either were weaned from the device or received a transplant for an overall discharge rate of 42%. The average effective hospital cost per survivor was almost $400,000.00. CONCLUSIONS: It is our belief that when considering the cost analysis of temporary devices, one must conclude that a more economical approach for the treatment of end-stage cardiac disease would be aggressive development of a permanent ventricular assist device.

Cardiac Surgical Procedures↗
PubMed1989

Complex role experiences and personal differentiation: a real-life experiment.

This paper analyses the relationship between the complexity of role experiences and personal differentiation. "Complex role experiences" are defined by high levels of voluntarism, multiplexity, quasi-responsibility and trial-and-error behaviour. The ability to differentiate between diverse principles of role enactment and various criteria of interpersonal relations is conceptualized as "personal differentiation". Our hypothesis is that a pre-designed educational programme providing complex role experiences enhances personal differentiation. This hypothesis was tested in an experimental study on Israeli adolescents participating in summer camps. The results show that the active exposure to and assumption of variegated roles in different settings on a voluntaristic basis, while performing meaningful and quasi-responsible actions by means of trial-and-error behaviour, enhances role and interpersonal differentiation, and hence personal differentiation, among adolescents.

Adolescent↗
PubMed2006

Can induced anxiety from a negative earlier experience influence vascular surgeons' statistical decision-making? A randomized field experiment with an abdominal aortic aneurysm analog.

BACKGROUND: Increasing detection, new screening recommendations, and popular press attention contribute to the rising prevalence of asymptomatic abdominal aortic aneurysms (AAA). Evidence-based guidelines recommend the optimal time to operate is when the aneurysm is 5.5 cm in diameter. Smaller AAAs are periodically monitored with imaging. Recent events and emotional reactions to risk and uncertainty, including anxiety, can cause decision-making to diverge from cognitively based assessments. It is not known whether this applies to vascular surgeons making statistically-optimal, risky decisions. We tested whether an unexpected, recent negative event might influence vascular surgeons' decisions about a computer-simulation AAA-analog that includes statistical information. STUDY DESIGN: We performed a randomized, computer-based field experiment with evidenced-based statistical information readily available on bursting probabilities. Participants included vascular surgeons with AAA operative experience attending two vascular surgery conferences held in 2005 (n=81). The intervention was a randomly assigned, anxiety-inducing, bursting balloon versus a nonbursting balloon before a statistical decision-making computer simulation. The main outcomes measure was real-time prospective choice to opt out of expanding AAA simulation. A Cox proportional hazard model was used to assess the likelihood of opting out, while controlling for important covariates. RESULTS: The experimental group was more likely to opt out (hazard ratio: 3.32; 95% CI: 1.25 to 8.81), even after controlling for initial anxiety levels, risk attitudes, uncertainty attitudes, use of statistical information, surgical experience, and demographics. CONCLUSIONS: Experiencing a negative, potentially anxiety-provoking, preceding event can influence decision-making, even among experienced vascular surgeons who have ready access to statistical risk information.

Adult↗
PubMed2006

The effect of medical experience on the economic evaluation of health policies. A discrete choice experiment.

In this paper we present results on the effect of medical experience on the economic evaluation of health policies utilizing the method of discrete choice experiments. Subjects in two split samples were asked about choice situations involving alternative profiles defined by the attributes of an innovative program for cervical cancer screening. The first sample was formed by expert medical practitioners who were familiar with the illness and its potential treatments. A second sample was formed by young undergraduate students in social sciences who were not familiar with the illness or with the potential benefits of screening programmes. The statistical comparison between both subsamples utilizes a robust method for discrete choice models which shows that there are no significant differences in the structural models and the parameter estimates. The main implication is that background medical information and familiarity with the process of illness might not have a relevant impact on the valuation of health policies with discrete choice experiments.

Adult↗
PubMed2000

Multiple-quantum MAS NMR of quadrupolar nuclei. Do five-, seven- and nine-quantum experiments yield higher resolution than the three-quantum experiment?

The question of whether or not higher-order (five-, seven- and nine-quantum) multiple-quantum magic angle spinning (MQMAS) experiments yield isotropic NMR spectra of half-integer quadrupolar nuclei with higher resolution than the basic three-quantum MAS experiment is examined. The frequency dispersion is shown theoretically to be greatly increased in higher-order MQMAS spectra, but it is argued that whether or not this translates into an increase in resolution depends upon the ratio of the homogeneous to inhomogeneous contributions to the isotropic linewidth. Experimentally, it is demonstrated using three-, five- and seven-quantum 45Sc MAS NMR and three- and five-quantum 27Al MAS NMR of crystalline samples that higher-order MQMAS experiments can yield a real and useful increase in resolution but that, owing to the presence of inhomogeneous broadening in the isotropic spectra, this increase is less than the theoretically predicted value. A number of practical issues relating to resolution in MQMAS NMR are also pointed out.

Aluminum↗
PubMed1995

Co-regulation of long-term potentiation and experience-dependent synaptic plasticity in visual cortex by age and experience.

Long-term potentiation (LTP) is a lasting enhancement of excitatory synaptic transmission that follows specific patterns of electrical stimulation. Although the mechanism of LTP has been intensively studied, particularly in the hippocampus, its significance for normal brain function remains unproven. It has been proposed that LTP-like mechanisms may contribute to naturally occurring, experience-dependent synaptic modifications in the visual cortex. The formation of normal binocular connections within the visual cortex requires simultaneous input from both eyes during a postnatal critical period that can be delayed by rearing animals in complete darkness. To explore the role of LTP in this experience-dependent maturation process, we induced LTP in visual cortical slices taken at different ages from light-reared and dark-reared rats. Susceptibility to LTP coincides with the critical period and, like the critical period, can be prolonged by rearing animals in darkness. These findings support the hypothesis that LTP reflects a normal mechanism of experience-dependent synaptic modification in the developing mammalian brain.

Aging↗
PubMed1978

[Therapeutic embolisation of visceral arteries. Animal experiments, early clinical experience and introduction of a new embolising material (author's transl)].

In order to compare the effectiveness and suitability of the most commonly used embolising materials--autologous blood clot, either pure or modified by epsilon-amino-caproic acid, gelatin, or fibrin foam--a series of experiments was carried out using the renal arteries of rabbits. Our own experience and the information in the literature indicate that there is at present no optimal and lasting material for embolisation. A new radioopaque for am consisting of a silicone elastomer has been found to be superior to all other materials, without any evidence of complication arising from it. Contrary to present views, it has been shown that the effect of embolisation is best demonstrated scintigraphically; angiography immediately after embolisation does not provide the necessary informatin (spasm, further thrombosis). The results of animal experiments and toxicity studies indicated that the substance can be used as suitable embolising material in patients, provided the indications are strictly controlled.

Angiography↗
PubMedDate not supplied

Enhanced undergraduate public health nursing experience: a collaborative experience with the Kentucky Department for Public Health.

The Kentucky Department for Public Health and the University of Kentucky College of Nursing entered into a collaborative partnership to provide an enhanced public health nursing experience for a select group of undergraduate students. The purpose of the project was to strengthen the public health nursing practices component of the baccalaureate nursing program in the College of Nursing at the University of Kentucky. The objectives of the project related to planning, implementing, and evaluating of this program in partnership with the Kentucky Cabinet for Health Services, State Health Department in Frankfort, Kentucky. The selected baccalaureate students were paired with a preceptor and a state, local, or district public health agency with an identified need in the student's area of interest. The students participated in a mentoring experience with a practicing public health nurse consultant. The experience afforded the students an opportunity to interact at both the practice and policy development levels. An ongoing partnership developed between the state health department, local health departments, and the college of nursing. This partnership led to ongoing practicum placements for students, beneficial for both the health departments and the college of nursing.

Community Health Services↗
PubMed1995

Dissociation and vulnerability to psychotic experience. The Dissociative Experiences Scale and the MMPI-2.

Prior research on the MMPI has cautioned against misdiagnosing schizophrenia in patients with dissociative identity disorder. The present study examined the full spectrum of the dissociative experience in relation to MMPI-2 profiles. Ninety-eight women in treatment for trauma-related disorders completed the Dissociative Experiences Scale and the MMPI-2 in routine inpatient diagnostic evaluations. Consistent with prior research, severe dissociation was associated with high elevations on MMPI-2 scales typically associated with psychotic symptoms. Contrary to hypotheses, the ostensibly most benign form of dissociation, absorption and imaginative involvement, was somewhat more strongly related to MMPI-2 scores than the more pathognomonic forms of dissociation, depersonalization and amnesia. Although it should not be misdiagnosed, severe impairment on the MMPI in conjunction with dissociation should be taken seriously as suggesting vulnerability to psychotic experience. The dissociative retreat from the stressors of outer reality opens the door to the inner world of traumatic images and affects, along with compromised reality testing and disorganized thinking.

Adult↗
PubMed2005

Magnetic resonance-guided large-core breast biopsy inside a 1.5-T magnetic resonance scanner using an automatic system: in vitro experiments and preliminary clinical experience in four patients.

RATIONALE AND OBJECTIVE: The aim of this study was to investigate the feasibility and the precision of magnetic resonance (MR)-guided large-core breast biopsies (LCBB) by using the second prototype of an automatic system (ROBITOM II), which is used to localize lesions while operating at the isocenter of a 1.5-T whole-body scanner. METHODS AND MATERIALS: In comparison to the first prototype, ROBITOM II is equipped with a dedicated double breast coil and a high-speed trocar setting unit. In vitro experiments (n = 25) with grapefruit phantoms, which contained multiple vitamin E capsules (12 x 7 mm in size) as artificial lesions, were performed. Four patients with MR-detectable breast lesions underwent biopsy. A trocar was positioned in front of the lesion and inserted into the breast. Specimens were harvested with a coaxial technique by using a 14-G core needle biopsy gun. RESULTS: In all 25 in vitro experiments, capsule material was detected in the specimen cylinder. In 4 patients, the coaxial needle was detected exactly at the expected position. Between 8 and 16 tissue cylinders were harvested. Histologic evaluation resulted in 1 invasive ductal carcinoma and 1 papilloma, which were confirmed after open surgery. One patient who had a proven breast cancer was biopsied for exclusion of multifocal disease. She showed fibrocystic changes, whereas open surgery revealed 3 small areas of ductal carcinoma in situ (DCIS). Another patient showed fibroadenoma after biopsy. This patient is in the follow-up period, which has lasted between 3 and 4 months up until now. CONCLUSIONS: In this pilot patient study, the feasibility of manipulator-assisted large-core breast biopsy inside a 1.5-T whole-body scanner was demonstrated by using ROBITOM II. The precision of the device was confirmed with in vitro experiments. Although these findings are preliminary and the follow-up period is rather short, they nevertheless represent a successful proof-of-principle of LCBB with ROBITOM II.

Biopsy, Needle↗
PubMed1997

Experience Producing Drive Theory: how genes drive experience and shape personality.

There is now a large body of evidence from twin and adoption studies linking genetic variation to phenotypic variation on virtually all human individual differences. Individuals unquestionably influence the nature of their experiences, e.g. high-sensation seekers surround themselves with like-minded peers and seek out quite different experiences than low-sensation seekers. We propose a theory called Experience Producing Drive Theory-Revised, to account for the current findings in behavior genetics. This theory is based on the Darwinian view that complex organisms are active agents "designed" by natural selection to survive in the environments in which they evolved. The theory assumes that the behavior of complex organisms can best be understood in terms of motives, preferences and emotional responses that have evolved to drive specific behavioral patterns. We propose a number of ways in which this theory might be falsified.

Animals↗
PubMed2003

Virtual optical experiments. Part II. Design of experiments.

In Part I of this study [J. Opt. Soc. Am. A 20, 698 (2003)], we presented a physically rigorous model for simulating optical probing techniques. We now introduce the concept of virtual experiments as the fundamental strategy for analyzing the measurement techniques and for supporting the design of the experiments. Thus a theoretical study of parasitic effects, the accuracy of the experiment, and the optimum probing conditions becomes possible. In our first example of application, free-carrier absorption measurements are discussed. We present quantitative results for the optimum sample geometry and the optimum optical setup. In addition, we demonstrate that backside laser probing, a typical representative of interferometric techniques, provides excellent spatial resolution and constitutes a powerful method to detect hot spots in the investigated sample.

Journal Article↗
PubMed2000

Dermatologic disease: twenty-two year experience at the USAF Aeromedical Consultation Service and review of other military and civilian experiences.

The Aeromedical Consultation Service (ACS) is a U.S. Air Force tertiary referral service which evaluates aviators with complex medical problems and makes recommendations for their aeromedical disposition. This study reports the experience with dermatologic disease in aviators referred to the ACS over a 22-yr period from 1975-1997. A review of other military and civilian experiences with dermatologic disease is also presented. The potential impact of skin disease on aviators and support personnel, in peacetime and wartime, can be surmised by this collective account of dermatologic experiences.

Adult↗
PubMedDate not supplied

[From the experience of Cheselden (1728) to the experiences of Dr. Guillie on contagious ophthalmia (1819-1820). Different methods of using those who were blind at birth as point of proof].

During the 18th century, oriented thinking about the origin of human knowledge, and the progress of ocular surgery, led to a number of observations on born blind recently cured from cataracts by famous surgeons. Such observations were continuously done during the 19th century, and they were interpreted either from the empiristic viewpoint or from the all along viewpoint. In 1820, Dr. Sebastien Guillie, manager and chief consultant at the Royal Institution for Younger Blind, prospected different experiments with four of his pupils, in order to prove the contagiousness of purulent ophtalmia. Despite the various differences between Dr. Guillie's experiments and his predecessors', the author voices that the century old habit of using blind people as subjects of experiment was the factor that allowed Guillie to grant permission using his pupils as guinea pigs.

Blindness↗
PubMed1986

The Experience of Electroconvulsive Therapy in the 1980s: A Prospective Study of the Knowledge, Opinions, and Experience of California Electroconvulsive Therapy Patients in the Berkeley Years.

In 1982, the city of Berkeley, California voted to make the use of electroconvulsive therapy (ECT) a crime. Though later overturned, this ordinance generated much publicity and underscored the public's general negative view of ECT. In this climate, the authors surveyed first-time ECT recipients (n = 35), and a group with prior ECT (n = 20) to examine patient knowledge, experience, and opinions of ECT in California in the 1980s. Patients in both groups believed ECT should be available and did not think it was used for punishment or control. First-time ECT patients showed good understanding of the ECT process, thought that they had adequate information with which to decide about ECT, and were optimistic about the outcome. In comparison, those with prior ECT were less knowledgeable, less sure about the ECT process, less optimistic about the outcome, and more frightened of the procedure. After treatment, first-time ECT patients believed they had made a good decision to have ECT and that they were helped. Complaints of memory dysfunction were common. Patients who received ECT in the past may have had a more negative experience with ECT than those undergoing the procedure in the 1980s. These more negative experiences may have determined present media presentations and, therefore, had an influence on present day public attitudes against ECT. Accurate portrayals of ECT, as it is done today, may improve public attitudes toward ECT and forestall adverse legislation.

Journal Article↗
PubMed2004

Discussion for animal experiments in space: ethical standard and responsibility of researchers for space experiments using laboratory animals.

International efforts to standardize regulations and study designs and to promote the principles of Reduction, Replacement, and Refinement (the 3 Rs) have reduced and refined animal use. In NASA ARC and KSC, researchers are responsible only for activities related directly to the conduct of their animal experiments. The IACUC plays an important role in conformity with NIH policies. Even if researchers design protocols of the space life science in Japan, the animal experiments should be carried out under the global harmonized conditions in accordance with NIH/NASA policies, guides and rules. It is important that researchers himself must look forward the ethical animal experiment.

Animal Welfare↗
PubMed1985

Immediate and long-term results of percutaneous transluminal coronary angioplasty. Comparison of the National Heart, Lung and Blood Institute Registry experience with current experience.

The immediate and long-term results of percutaneous transluminal coronary angioplasty (PTCA) in 1939 patients with single-vessel coronary disease (SVD) from the National Heart, Lung and Blood Institute Registry on PTCA (early experience) have been compared to recent results in 1551 patients, also with SVD, pooled from three centers in the USA (current experience). The circumflex artery, rarely subjected to PTCA in the past, now constitutes 16% of the total. The success rate has increased from 65 to 92% and, contrary to previous results, all three coronary arteries share at present a similar rate of success. The complications rate has been halved from 8.4 to 4.2%. These differences stem from the present level of operator expertise and the improved instrumentation. On the other hand, the severity of coronary stenosis and its reduction in successfully treated patients, as well as the rate of recurrence after successful PTCA in the current experience, show no difference from the past. The possible reasons for these similarities are only speculative at this time.

Angina Pectoris↗