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131.
The aim of this study was to compare the estimated public medical care cost of measures to address metallic dental restorations (MDRs) for head and neck radiotherapy using high-energy mega-voltage X-rays. This was considered a first step to clarify which MDR measure was more cost-effective. We estimated the medical care cost of radiotherapy for two representative MDR measures: (i) with MDR removal or (ii) without MDR removal (non-MDR removal) using magnetic resonance imaging and a spacer. A total of 5520 patients received head and neck radiation therapy in 2018. The mean number of MDRs per person was 4.1 dental crowns and 1.3 dental bridges. The mean cost per person was estimated to be 121 720 yen for MDR removal and 54 940 yen for non-MDR removal. Therefore, the difference in total public medical care cost between MDR removal and non-MDR removal was estimated to be 303 268 800 yen. Our results suggested that non-MDR removal would be more cost-effective than MDR removal for head and neck radiotherapy. In the future, a national survey and cost-effectiveness analysis via a multicenter study are necessary; these investigations should include various outcomes such as the rate of local control, status of oral mucositis, frequency of hospital visits and efforts of the medical professionals.  相似文献   
132.
We investigated prospectively in 128 patients (140 eyes) the role of six routine clinical tests in the differentiation of ischemic central retinal vein occlusion (CRVO) from non-ischemic CRVO during its early acute phase. There were fourfunctional tests [visual acuity, visual fields, relative afferent pupillary defect (RAPID), electroretinography (ERG)] and twomorphologic tests (ophthalmoscopy and fluorescein fundus angiography). We found that none of the six tests had 100% sensitivity and specificity in such a differentiation during the early, acute phase, so that no one test can be considered a gold standard; however, combined information from all six is almost always reliable. Overall, the four functional tests proved far superior to the two morphologic tests in differentiating ischemic from non-ischemic CRVO: RAPID was most reliable in uniocular CRVO (with a normal fellow eye), followed closely by ERG in all cases; combined information from RAPID and ERG differentiated 97% of cases; perimetry was the next most reliable, followed by visual acuity. The two morphologic tests performed worst; fluorescein angiography provided either no information at all on retinal capillary nonperfusion (in at least one-third of the eyes during the early, acute phase) because of multiple limitations, or sometimes provided misleading information. Ophthalmoscopic appearance is the least reliable, most misleading parameter.A preliminary summary of this was presented at the Macula Society Meeting, Cannes, France (June, 1987) and at the XVIth Meeting of the Club Jules Gonin, Bruges, Belgium, 4–8 September 1988. This investigation was supported by grant EY-1151 from the National Institutes of Health and, in part, by unrestricted grants from Research to Prevent Blindness, Inc., and from Alcon Research Institute  相似文献   
133.
134.
Objective To develop a new chemical method to produce a monoclonal antibody (MoAb) 520C9/recombinant human interleukin 2 (rhIL-2) conjugate. Methods MoAb 520C9 reactive with the protooncogene c-erbB-2 product P185 was chemically conjugated with rhIL-2 by using a simple two-step method.First, the rhIL-2 was activated by Sulfosuccinimidyl 4-[N-maleimidomethyl] cyclohexane-1-carboxylate, a heterobifunctional linker, and N-succinimidyl s-acetylthioacetate was introduced onto 520C9.Then SATA on the 520C9 was reacted with the maleimide group on the activated rhIL-2 to generate 520C9-rhIL-2 immunoconjugate. Results The immunoconjugate retained the antigen binding activity compared to the respective native antibody as determined by an indirect live cell binding assay.The immunoconjugate also possessed IL-2 activity as measured by the standard CTLL-2 cells proliferation assay and the stimulation of human peripheral blood mononuclear cells (PBMCs) into lymphokine-activated killer cells. Conclusion Our method of conjugation of rhIL-2 to 520C9 preserves the binding activity of the antibody and the cytokine function of IL-2.This simple and efficient method of conjugation should be applicable to other types of MoAbs and recombinant cytokines.  相似文献   
135.
Four members of a three-generation Czech family with early-onset chorioretinal dystrophy were shown to be heterozygous carriers of the n.37C>T in MIR204. The identification of this previously reported pathogenic variant confirms the existence of a distinct clinical entity caused by a sequence change in MIR204. Chorioretinal dystrophy was variably associated with iris coloboma, congenital glaucoma, and premature cataracts extending the phenotypic range of the condition. In silico analysis of the n.37C>T variant revealed 713 novel targets. Additionally, four family members were shown to be affected by albinism resulting from biallelic pathogenic OCA2 variants. Haplotype analysis excluded relatedness with the original family reported to harbour the n.37C>T variant in MIR204. Identification of a second independent family confirms the existence of a distinct MIR204-associated clinical entity and suggests that the phenotype may also involve congenital glaucoma.  相似文献   
136.
OBJECTIVES: To assess the status of managed care and insurance coverage of complementary and alternative medicine (CAM) and the integration of such services offered by hospitals. METHODS: A literature review and information search was conducted to determine which insurers had special policies for CAM and which hospitals were offering CAM. Telephone interviews were conducted with a definitive sample of 18 insurers and a representative subsample of seven hospitals. RESULTS: A majority of the insurers interviewed offered some coverage for the following: nutrition counseling, biofeedback, psychotherapy, acupuncture, preventive medicine, chiropractic, osteopathy, and physical therapy. Twelve insurers said that market demand was their primary motivation for covering CAM. Factors determining whether insurers would offer coverage for additional therapies included potential cost-effectiveness based on consumer interest, demonstrable clinical efficacy, and state mandates. Some hospitals are also responding to consumer interest in CAM, although hospitals can only offer CAM therapies for which local, licensed practitioners are available. Among the most common obstacles listed to incorporating CAM into mainstream health care were lack of research on efficacy, economics, ignorance about CAM, provider competition and division, and lack of standards of practice. CONCLUSIONS: Consumer demand for CAM is motivating more insurers and hospitals to assess the benefits of incorporating CAM. Outcomes studies for both allopathic and CAM therapies are needed to help create a health care system based upon treatments that work, whether they are mainstream, complementary, or alternative.  相似文献   
137.
Background: The highly swelling poly(glycerol monomethacrylate) gel (polyGLYMA) and hydrophilic polymer poly(triethylenglycol monomethacrylate (polyTEGMA) were tested as potential viscoelastics for intraopertive use in anterior segment surgery. Methods: PolyGLYMA was implanted into the anterior chamber in 5 rabbits, and 40% polyTEGMA in 16 rabbits. The eyes were enucleated 1 week to 3 months after the operation. The corneal endothelium was examined with specular microscopy, and then the whole eye histopathologically. Results: In all eyes of the polyGLYMA group, the clinical findings were characterized by a marked ciliary injection and severe secondary glaucoma, and the histologic ones by a marked inflammatory infiltration and thickening of Descemet's membrane in the anterior chamber angle. Specular microscopy revealed a decrease in the endothelial cell density and polymorphism of the endothelial cells. In the polyTEGMA group, the anterior segment and the fundus were physiologic all the time, and specular microscopy and histologic findings showed no degenerative and/or inflammatory changes. Conclusions: PolyGLYMA proved unsuitable for intracameral application in rabbits. The new polymer polyTEGMA is characterized by high biologic tolerance after its implantation into the anterior chamber of rabbits. PolyTEGMA 40% might be considered as a potential viscoelastic material in humans.  相似文献   
138.
Localized brain activation in response to moving visual stimuli was studied by functional magnetic resonance imaging (fMRI). Stimuli were 100 small white dots randomly arranged on a visual display. During the Motion condition, the dots moved along random, noncoherent linear trajectories at different velocities. During the Blink condition, the dots remained stationary but blinked on and off every 500 ms. The Motion and Blink conditions continuously alternated with 10 cycles per run and 6–8 runs per experiment. In half of the runs, the starting stimulus condition was Motion, while in the remaining runs it was Blink. A series of 128 gradient echo echoplanar images were acquired from 5–7 slices during each run using a 1.5 T GE Signa with an Advanced NMR echoplanar subsystem. The time series for each voxel were analyzed in the frequency domain. Voxels which demonstrated a significant spectral peak at the alternation frequency and whose phase changed in response to stimulus order were considered activated. These activated voxels were displayed upon high resolution anatomical images to determine the sites of activation and were also transformed into the coordinates of Talairach and Tournoux ([1988] Co-planar Stereotaxic Atlas of the Human Brain, New York: Thieme) for comparison to prior neuroimaging studies. Seven of ten subjects showed clusters of activation bilaterally at the junction of the temporal and occipital lobes (area 37) in response to moving stimuli. Most activated voxels were located within or adjacent to a region designated the parietal-temporal-occipital fossa, or PTOF. Five subjects also showed activation to moving stimuli in midline occipital cortex. The activated voxels in midline cortex had a significantly shorter phase delay in their MR signal change relative to voxels in PTOF. © 1995 Wiley-Liss, Inc. 1
  • 1 This article is a US Government work and, as such, is in the public domain in the United States of America
  •   相似文献   
    139.
    An important aspect of primary care physician availability is the retention of physicians once they have located. While retention has been under-researched compared to recruitment, it is especially important in rural areas where physician shortages already exist. This study reports the results of a retention survey completed by 132 primary care physicians in rural eastern Kentucky. The survey sets up an objective, hypothetical retention scenario and asks physicians to respond to structured questions and to an open-ended question about factors not appearing in the survey. In response to the structured portion of the survey, physicians indicate that relief coverage is the most important factor in rural physician retention. A content analysis of 75 open-ended responses reveals that besides the other factors in the survey, "sociocultural integration" is the pre-eminent retention issue for rural practitioners. This article concludes that the role of the local rural community may be more important in retention than in recruitment. Finally, it is suggested that additional in-depth qualitative research be conducted within the local contexts to enhance the understanding of rural physician retention processes.  相似文献   
    140.
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