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1.
ABSTRACT

Communication between health professionals and patients is an intergroup phenomenon where the health professional has the most power and status. Over the past few decades, there has been a steady increase in the availability to patients of information about healthcare and specific diseases on the Internet. In this paper, we ask whether the use of Internet health information assists patients to manage their consultations with health professionals better and whether it alters the intergroup dynamic by providing a more equal status for patients. In this study 370 participants from Australia and Canada completed a survey that included a ‘willingness to communicate with health professionals’ scale. They also commented on their use and trust of Internet health information. Thematic analysis suggests that patients’ use of Internet health information serves as a broker between patients and their health provider in health consultations. We discuss the implications of these findings for health practitioners as they address how easier Internet access influences patient interactions with health professionals. We consider future research directions these finding provide in explaining communication behaviour in this context.  相似文献   
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A genetic analysis of mammalian neuronal physiology might now be possible due to the development of defective herpes simplex virus vectors, which allow gene transfer directly into mature neurons, in culture or in the adult brain. Genetically altered proteins that play critical roles in neuronal physiology, including those responsible for the generation of action potentials, synthesis and release of neurotransmitters, and signal transduction enzymes, can now be stably expressed in neurons. The effect of such altered proteins on neuronal physiology can therefore be examined, using the tools of modern neuroscience. Genetic manipulation is biochemically specific and stable, and can be targeted both to a particular cell type and to a particular subregion of the cell to yield insights into the molecular basis for specific brain functions.  相似文献   
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Background: Anesthesiologists and anesthesia residents are expected to acquire and maintain skills to manage a wide range of acute intraoperative anesthetic events. The purpose of this study was to determine whether an inventory of simulated intraoperative scenarios provided a reliable and valid measure of anesthesia residents' and anesthesiologists' skill.

Methods: Twelve simulated acute intraoperative scenarios were designed to assess the performance of 64 residents and 35 anesthesiologists. The participants were divided into four groups based on their training and experience. There were 31 new CA-1, 12 advanced CA-1, and 22 CA-2/CA-3 residents as well as a group of 35 experienced anesthesiologists who participated in the assessment. Each participant managed a set of simulated events. The advanced CA-1 residents, CA-2/CA-3 residents, and 35 anesthesiologists managed 8 of 12 intraoperative simulation exercises. The 31 CA-1 residents each managed 3 intraoperative scenarios.

Results: The new CA-1 residents received lower scores on the simulated intraoperative events than the other groups of participants. The advanced CA-1 residents, CA-2/CA-3 residents, and anesthesiologists performed similarly on the overall assessment. There was a wide range of scores obtained by individuals in each group. A number of the exercises were difficult for the majority of participants to recognize and treat, but most events effectively discriminated among participants who achieved higher and lower overall scores.  相似文献   

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Subclasses of receptors exist for most neurotransmitters. Frequently, two subtypes of receptors coexist in the same tissue and, in some cases, they mediate the same physiological response. In tissues with two classes of binding sites for a given hormone, an estimate of the proportion of each class of binding sites is obtained by inhibiting the binding of a single concentration of a radioligand with a selective unlabeled ligand. Accurate estimates of the density of each class of receptors will only be obtained, however, if the radioligand is entirely nonselective. Selectivity of just 2- to 3-fold can markedly influence the results of subtype analysis. The conclusion that a radioligand is nonselective is usually based on the results of a saturation binding curve. If Scatchard analysis of such data results in a linear plot, then it is concluded that the radioligand is nonselective. However, Scatchard analysis cannot distinguish between a radioligand that is nonselective and one that is slightly selective. The use of a slightly selective radioligand can lead to errors of 50% or more, depending on the concentration of the radioligand relative to the Kd values of the two classes of sites. A new analytical method has been developed that can be used to quantitate 2- to 3-fold differences in the affinity of two distinct classes of binding sites for a radioligand. This new approach requires that a series of inhibition experiments with a selective unlabeled ligand be performed in the presence of increasing concentrations of the radioligand. Analysis of the resulting inhibition curves, utilizing the mathematical modeling program MLAB on the PROPHET system, yields accurate estimates of the density of each class of receptor as well as the affinity of each receptor for the labeled and unlabeled ligands. This approach was used to determine whether 125I-iodopindolol shows selectivity for beta 1- or beta 2-adrenergic receptors. A series of inhibition curves was generated with the unlabeled ligands ICI 89,406 (beta 1-selective) and ICI 118,551 (beta 2-selective), using membranes prepared from C6 glioma cells. These cells contain both beta 1- and beta 2-adrenergic receptors. 125I-Iodopindolol was determined to be 3-fold selective for beta 2-adrenergic receptors. Since the sensitivity of this approach is superior to that of Scatchard analysis, it is likely that other radioligands, previously thought to be nonselective, will be shown to be selective when analyzed by this method.  相似文献   
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Allogeneic hematopoietic stem cell transplantation (HSCT) is established therapy for selected patients with acute leukemia. After transplantation, antileukemic immune responses are believed to eliminate residual leukemia cells and decrease the likelihood of relapse. However, the clinical effect of successful antigen-specific immune reconstitution after HSCT on the likelihood of leukemic relapse and overall survival is not known. Pediatric recipients of unrelated cord blood transplants who underwent transplantation for acute leukemia were sequentially evaluated for their development of antigen-specific T-lymphocyte immunity to herpes viruses. The clinical effect of a positive antigen-specific response on relapse-free survival was determined. The presence of an antigen-specific response resulted in a relapse-free survival advantage (P = .0001), which was primarily due to a decrease in leukemic relapse (P = .003). Proportional hazards modeling for time to relapse and time to relapse or death defined 3 variables that were strongly associated with a poor outcome: female gender, poor remission status before transplantation, and negative antigen-specific T-lymphocyte proliferation. Notably neither acute nor chronic graft-versus-host disease had any effect on the incidence of leukemic relapse. Successful antigen-specific immune reconstitution after unrelated cord blood transplantation results in decreased leukemic relapse and improved overall survival.  相似文献   
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ABSTRACT: This study used formative evaluation to identify channels and barriers to providing ongoing dietary guidance to pregnant teens in New Jersey. In phase one, 14 health and social service professionals participated in a focus group or interview about nutrition services for pregnant teens. Participants identified school nurses as potential providers of early and continuous dietary counseling to pregnant teen-agers, but delineated barriers to establishment and effectiveness of school-based, prenatal nutrition education. In phase two, school nurses were surveyed to assess their interest in, and perceptions of barriers to, providing nutrition education to pregnant adolescents. Two-hundred fifty-three nurses (71%) returned completed questionnaires. Results indicated that a significant proportion perceived a need for, and were interested in providing, nutrition education to pregnant students. Results from this formative research are being used to guide development of a school-based nutrition education program for pregnant teen-agers in New Jersey.  相似文献   
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Public concern surrounding antibiotic contamination in food and food products has made it imperative to develop analytical methods for their detection. Polyclonal antibodies were used in the development of a surface plasmon resonance (SPR)-based inhibition immunoassay for cephalexin. A conjugate consisting of cephalexin-bovine serum albumin (BSA) was immobilized on the dextran gel surface of the sensor chip. Binding/regeneration studies of antibody to immobilized cephalexin were studied and dissociation of the antibody from the immobilized cephalexin was easily achieved with 10 mmol l-1 NaOH. Forty surface regeneration cycles were carried out and found to be reproducible with only a 7.4% decrease in binding over this number of regenerations. Model inhibition immunoassays for cephalexin were developed in PBS and spiked milk samples with detection ranges of 4.88 to 2,500 ng ml-1 and 244 to 3,906 pg ml-1, respectively.  相似文献   
10.
Bone mineral density (BMD) was assessed by dual-photon X-ray absorptiometry at the lumbar spine (L3, L4), the proximal femur and the femoral shaft, and by single-photon absorptiometry at the forearm in 53 patients with complete traumatic paraplegia of at least 1 year's duration and in age- and sex-matched healthy controls. The patients did (n=38) or did not (n=15) regularly perform passive weightbearing standing with the aid of a standing device. Compared with the controls, the BMD of paraplegic patients was preserved in the lumbar spine and was markedly decreased in the proximal femur (33%) and the femoral shaft (25%). When considering all patients performing standing, they had a better-preserved BMD at the femoral shaft (p=0.009), but not at the proximal femur, than patients not performing standing. BMD at the lumbar spine (L3,L4) was marginally higher in the standing group (significant only for L3;p=0.040). A subgroup of patients performing standing with use of long leg braces had a significantly higher BMD at the proximal femur than patients using a standing frame or a standing wheelchair (p=0.030). The present results suggest that passive mechanical loading can have a beneficial effect on the preservation of bone mass in osteoporosis found in paraplegics.  相似文献   
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