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1.
PurposeManagement of head and neck cancers (HNC) in older adults is a common but challenging clinical scenario. We assess the impact of Stereotactic Body Radiation Therapy (SBRT) on survival utilizing the Geriatric-8 (G8) questionnaire.Materials and methods171 HNC patients, deemed medically unfit for definitive treatment, were treated with SBRT ± systemic therapy. G8 questionnaires were collected at baseline, at 4–6 weeks, and at 2–3 months post-treatment. Patients were stratified according to their baseline G8 score: <11 as ‘vulnerable’, 11–14 as ‘intermediate’, and >14 as ‘fit’. Overall survival (OS) was assessed through univariate Kaplan Meier analysis. Repeated measures ANOVA was used to determine if baseline characteristics affected G8 score changes.ResultsMedian follow-up was seventeen months. 60% of patients presented with recurrent HNC, 30% with untreated HNC primaries, and 10% with metastatic non-HNC primaries. Median age was 75 years. Median Charlson Comorbidity Index score was 2. 51% of patients were ‘vulnerable’, 37% were ‘intermediate’, and 12% were ‘fit' at baseline, with median survival of 13.2, 24.3, and 41.0 months, respectively (p = .004). Patients who saw a decrease in their follow-up G8 score (n = 69) had significantly lower survival than patients who had stable or increased follow-up G8 scores (n = 102), with median survival of 8.6 vs 36.0 months (p < .001).ConclusionThe G8 questionnaire may be a useful tool in upfront treatment decision-making to predict prognosis and prevent older patients from receiving inappropriate anti-cancer treatment. Decline in follow-up G8 scores may also predict worse survival and aid in goals of care following treatment.  相似文献   
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In contrast with cross-sectional designs used in previous studies, this exploratory study compared survey data from 127 matched pairs of clinical pharmacists and physicians working together. Physicians' perceptions of the importance of clinical pharmacy activities for patient care and the competence of pharmacists performing the activities were examined for their influence on prescribing behavior in an institutional setting. Data from a national survey showed that physicians rated pharmacists higher regarding recommendations based on drug use evaluations (p = 0.004) and competency to provide all clinical pharmacy services. Scores for pharmacokinetics ratings were similar between pharmacists and physicians (p = 0.168). Pharmacists rated the importance of recommendations based on cost-effectiveness higher than physicians (p = 0.012). Overall, physicians' perceptions of activity importance for patient care and pharmacist competency appear to dictate pharmacists' influence on physician prescribing behavior (R = 0.723).  相似文献   
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We report a case of malakoplakia in association with colonic adenocarcinoma. Tumour-associated malakoplakia in the gastrointestinal tract is a rare finding, generally confined to the colon. It may be locally aggressive, with invasion of pericolic tissues, but is always located adjacent to the tumour. This contrasts with the often more diffuse, multifocal distribution of colonic malakoplakia in association with other pathologies.  相似文献   
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Resistant strains of Escherichia coli were obtained by stepwise cultivation in subinhibitory concentrations of two antimicrobially active amine oxides. Changes in the chemical composition of the outer membrane of the resistant strains were accompanied also by different antigenic reactions. New precipitation lines were revealed by double immunodiffusion and immuno-electrophoretic methods. The results of immunochemical analysis confirm the findings that the resistance to amphiphilic compounds is associated with the outer membrane which limits the access of antimicrobially active molecules to their sites of action in the cytoplasmic membrane.  相似文献   
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A large proportion of stroke survivors have to deal with problems in mobility. Proper evaluations must be undertaken to understand the sensorimotor impairments underlying locomotor disorders post stroke, so that evidence-based interventions can be developed. The current electrophysiological, biomechanical, and imagery evaluations that provide insight into locomotor dysfunction post stroke, as well as their advantages and limitations, are reviewed in this paper. In particular, electrophysiological evaluations focus on the contrast of electromyographic patterns and integrity of spinal reflex pathways during perturbed and unperturbed locomotion between persons with stroke and healthy individuals. At a behavioral level, biomechanical evaluations that include temporal distance factors, kinematic and kinetic analyses, as well as the mechanical energy and metabolic cost, are useful when combined with electrophysiological measures for the interpretation of gait disturbances that are related to the control of the central nervous system or secondary to biomechanical constraints. Finally, current methods in imaging and transcranial magnetic stimulation can provide further insight into cortical control of locomotion and the integrity of the corticospinal pathways.  相似文献   
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Amorphous hydrogenated carbon (a-C:H) films have many outstanding properties required for a protective coating material on load bearing medical implants. Recently, titanium doped a-C:H films have been evaluated regarding their effects on bone marrow cell cultures. But many materials that are well-tolerated in bulk form are able to induce toxic reaction if present particulate form. In order to further assess biocompatibility aspects of these two coatings, film delamination has been mimicked in exposure to fluids. In the present study, particles from a-C:H, a-C:H/Ti and a-C:H-a-C:H/Ti bilayer films were added to bone marrow cell cultures in vitro. The results showed that plain a-C:H and to a certain extent a-CH/Ti particles were inert. Both kinds of particles did not significantly stimulate the osteoclast-related enzyme tartrate resistant acid phosphatase (TRAP). A slight increase in cell proliferation and total culture TRAP was found in cultures treated by a-C:H-a-C:H/Ti bilayer films. Latter effect can probably be traced back by the relative high percentage of small particles of a size of around 2 microm. However, if corrected by the cell number also no differences between particle-treated and untreated control cultures could be found, indicating the absence of a toxic effect from delaminated a-C:H coatings.  相似文献   
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Much is known about specific antibodies and their titers in patients with tuberculosis. However, little is known about the avidity of these antibodies or whether changes in avidity occur during the progression of the disease or during treatment. The aims of this study were to determine the avidity of antibodies to Mycobacterium tuberculosis in patients with pulmonary tuberculosis, to explore the value of avidity determination for the diagnosis of tuberculosis, and to study changes in levels of antibodies and their avidity during treatment. Antibody avidity was measured by an enzyme-linked immunosorbent assay with thiocyanate elution. Avidity indices and serum levels of immunoglobulin G to M. tuberculosis were determined for 22 patients with pulmonary tuberculosis before and during treatment and for 24 patients with other pulmonary diseases. Antibody levels and avidity were both significantly higher in untreated tuberculosis patients than in the controls. Avidity determination had more diagnostic potential than determination of the antibody levels. Tuberculosis patients with a long duration of symptoms had higher antibody avidity than those with a recent onset of symptoms, indicating affinity maturation of specific antibodies during active disease. In the early phase of treatment, a decrease in antibody avidity was observed for 73% of all tuberculosis patients, accompanied by an initial increase in antibody levels in 36% of these patients. These phenomena could be explained by an intense stimulation of the humoral response by antigens released from killed bacteria, reflecting early bactericidal activity of antituberculous drugs leading to the production of low-affinity antibodies against these released antigens.  相似文献   
10.
The authors compared two methodological approaches, Jackknife ROC and JAFROC, in analyzing data ascertained during FROC (free-response receiver operating characteristics) type studies. Observer rating data obtained from two observer performance studies were analyzed. During the first study, seven radiologists interpreted 120 mammography examinations depicting 57 masses under five different conditions with and without the results of computer-aided detection (CAD). In the second study, eight radiologists interpreted 110 examinations depicting 51 masses under six different display conditions with and without CAD results. Readers rated the detection task in a FROC type response. Jackknife ROC (using the software of LABMRMC with the highest rating per case) and JAFROC were used to compute differences, if any, in summary performance levels among all reading modes in each study as well as for all paired data sets. The results of the different analytical approaches are compared. The overall results for all modes were significantly different for the first study (p < 0.05) and not significant (p > 0.05) for the second study using either analytical approach. In the first study, the performance levels represented by three paired data sets were significantly different (p < 0.05) when computed using LABMRMC and four pairs were significantly different (p < 0.05) using JAFROC. In eight of ten pairs, JAFROC produced lower p values than LABMRMC. In the second study, LABMRMC showed no significant differences for any paired data sets and JAFROC showed a significant difference for one pair. In 15 of 16 pairs, p values computed by JAFROC were lower than those computed by LABMRMC.  相似文献   
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