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61.
No relationship between prenatal androgen exposure and autistic traits: convergent evidence from studies of children with congenital adrenal hyperplasia and of amniotic testosterone concentrations in typically developing children 下载免费PDF全文
62.
Prediction of children's reading skills using behavioral, functional, and structural neuroimaging measures 总被引:1,自引:0,他引:1
Hoeft F Ueno T Reiss AL Meyler A Whitfield-Gabrieli S Glover GH Keller TA Kobayashi N Mazaika P Jo B Just MA Gabrieli JD 《Behavioral neuroscience》2007,121(3):602-613
The ability to decode letters into language sounds is essential for reading success, and accurate identification of children at high risk for decoding impairment is critical for reducing the frequency and severity of reading impairment. We examined the utility of behavioral (standardized tests), and functional and structural neuroimaging measures taken with children at the beginning of a school year for predicting their decoding ability at the end of that school year. Specific patterns of brain activation during phonological processing and morphology, as revealed by voxel-based morphometry (VBM) of gray and white matter densities, predicted later decoding ability. Further, a model combining behavioral and neuroimaging measures predicted decoding outcome significantly better than either behavioral or neuroimaging models alone. Results were validated using cross-validation methods. These findings suggest that neuroimaging methods may be useful in enhancing the early identification of children at risk for poor decoding and reading skills. 相似文献
63.
Macular degeneration is the most common cause of blindness in individuals over 50 years of age. The condition is frequently classified into the categories of early, intermediate, and advanced stages. Current interventions concerning macular degeneration include a healthy lifestyle, diet, medical intervention, surgery, and environmental assistance. Future strategies for individuals with macular degeneration will possibly stress gene therapy, retinal transplantation, artificial vision, retinal prosthesis, and neuroprotection. 相似文献
64.
Amit K. Mathur Zoe A. Stewart Lewis Patricia H. Warren Marie‐Claire Walters Kimberly A. Gifford Jiawei Xing Nathan P. Goodrich Renee Bennett Ada Brownson Jill Ellefson Gerardo Felan Barrett Gray Rebecca E. Hays Cathy Klein‐Glover Shelley Lagreco Nancy Metzler Kimberly Provencher Emily Walz Kara Warmke Robert M. Merion Akinlolu O. Ojo 《American journal of transplantation》2020,20(1):25-33
Living organ donors face direct costs when donating an organ, including transportation, lodging, meals, and lost wages. For those most in need, the National Living Donor Assistance Center (NLDAC) provides reimbursement to defray travel and subsistence costs associated with living donor evaluation, surgery, and follow‐up. While this program currently supports 9% of all US living donors, there is tremendous variability in its utilization across US transplant centers, which may limit patient access to living donor transplantation. Based on feedback from the transplant community, NLDAC convened a Best Practices Workshop on August 2, 2018, in Arlington, VA, to identify strategies to optimize transplant program utilization of this valuable resource. Attendees included team members from transplant centers that are high NLDAC users; the NLDAC program team; and Advisory Group members. After a robust review of NLDAC data and engagement in group discussions, the workgroup identified concrete best practices for administrative and transplant center leadership involvement; for individuals filing NLDAC applications at transplant centers; and to improve patient education about potential financial barriers to living organ donation. Multiple opportunities were identified for intervention to increase transplant programs’ NLDAC utilization and reduce financial burdens inhibiting expansion of living donor transplantation in the United States. 相似文献
65.
SJ Smith CV Rahman PA Clarke AA Ritchie TW Gould JH Ward KM Shakesheff RG Grundy R Rahman 《Annals of the Royal College of Surgeons of England》2014,96(7):495-501
Introduction
The median survival of patients with glioblastoma multiforme (astrocytoma grade 4) remains less than 18 months despite radical surgery, radiotherapy and systemic chemotherapy. Surgical implantation of chemotherapy eluting wafers into the resection cavity has been shown to improve length of survival but the current licensed therapy has several drawbacks. This paper investigates in vivo efficacy of a novel drug eluting paste in glioblastoma.Methods
Poly(lactic-co-glycolic acid)/poly(ethylene glycol) (PLGA/PEG) self-sintering paste was loaded with the chemotherapeutic agent etoposide and delivered surgically into partially resected tumours in a flank murine glioblastoma xenograft model.Results
Surgical delivery of the paste was successful and practical, with no toxicity or surgical morbidity to the animals. The paste was retained in the tumour cavity, and preliminary results suggest a useful antitumour and antiangiogenic effect, particularly at higher doses. Bioluminescent imaging was not affected significantly by the presence of the paste in the tumour.Conclusions
Chemotherapy loaded PLGA/PEG paste seems to be a promising technology capable of delivering active drugs into partially resected tumours. The preliminary results of this study suggest efficacy with no toxicity and will lead to larger scale efficacy studies in orthotopic glioblastoma models. 相似文献66.
Matthew S. Herbert M.A. Burel R. Goodin Ph.D. Samuel T. Pero IV B.S. Jessica K. Schmidt B.A. Adriana Sotolongo M.P.H. Hailey W. Bulls B.S. Toni L. Glover Ph.D. GNP-BC Christopher D. King Ph.D. Kimberly T. Sibille Ph.D. Yenisel Cruz-Almeida M.S.P.H. Ph.D. Roland Staud M.D. Barri J. Fessler M.D. M.S.P.H. Laurence A. Bradley Ph.D. Roger B. Fillingim Ph.D. 《Annals of behavioral medicine》2014,48(1):50-60
Background
Pain hypervigilance is an important aspect of the fear-avoidance model of pain that may help explain individual differences in pain sensitivity among persons with knee osteoarthritis (OA).Purpose
The purpose of this study was to examine the contribution of pain hypervigilance to clinical pain severity and experimental pain sensitivity in persons with symptomatic knee OA.Methods
We analyzed cross-sectional data from 168 adults with symptomatic knee OA. Quantitative sensory testing was used to measure sensitivity to heat pain, pressure pain, and cold pain, as well as temporal summation of heat pain, a marker of central sensitization.Results
Pain hypervigilance was associated with greater clinical pain severity, as well as greater pressure pain. Pain hypervigilance was also a significant predictor of temporal summation of heat pain.Conclusions
Pain hypervigilance may be an important contributor to pain reports and experimental pain sensitivity among persons with knee OA. 相似文献67.
68.
69.
Site-directed mutagenesis of histidine residues involved in Cu(II) binding and reduction by sperm whale myoglobin. 下载免费PDF全文
B R Van Dyke D A Bakan K A Glover J C Hegenauer P Saltman B A Springer S G Sligar 《Proceedings of the National Academy of Sciences of the United States of America》1992,89(17):8016-8019
Sperm whale myoglobin (Mb) reduces Cu(II) through a site-specific mechanism involving complexation by one or more surface histidine residues. Three mutants of Mb, derived from recombinant wild-type Mb, were designed in which surface histidine residues exhibiting strong Cu(II) binding were replaced with amino acids with comparatively poor metal binding characteristics. The kinetics of Cu(II)(Gly)2 reduction by native Mb, recombinant wild-type Mb, and the mutants were compared. Recombinant wild-type Mb reduced Cu(II) at a rate similar to that of native Mb. Two single mutations (His-48----Ala and His-116----Asp) decreased the rate by 31% and 7%, respectively, relative to wild-type Mb and decreased the rate by 38% and 16%, respectively, relative to native Mb. A double mutation (His-113----Ala, His-116----Asp) decreased the rate only slightly more than the single mutation at His-116. Previous NMR studies showed that His-113 exhibits the strongest Cu(II) binding of all surface histidines, but the present experiments suggest that it plays little or no role in the reduction of Cu(II) by Mb. His-48, located 12.7 A from the Fe(II)-heme, participates in one-third of the redox activity of the protein. His-116 appears to play a minor role in the overall redox activity of Mb, but its involvement shows that Mb has the ability to reduce Cu(II) through a histidine residue located more than 20 A from the Fe(II)-heme. These experiments demonstrate that electron transport from the Fe(II)-heme to site-specifically bound Cu(II) can be mediated through multiple pathways in sperm whale Mb. 相似文献
70.
C D Allis C V Glover M A Gorovsky 《Proceedings of the National Academy of Sciences of the United States of America》1979,76(10):4857-4861
Evidence is presented that micronuclei of Tetrahymena thermophila contain significant amounts of two types of histone H3. One is indistinguishable from that found in macronuclei and the other is unique to micronuclei. The micronucleus-specific H3 has a slightly faster mobility than the common H3 in three different gel systems (both of these species were artifactually lost during procedures for histone preparation in previous studies). Both micronuclear H3s appear to contain a single cysteine residue and are present in sucrose gradient-purified nucleosomes. Acid extracts from micronuclei also contain three prominent high molecular weight proteins that also were lost during previous procedures. These proteins are present in extracts from oligomers but are not observed in extracts from mononucleosomes, suggesting that they may be associated with linker regions between nucleosomes. 相似文献