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排序方式: 共有1628条查询结果,搜索用时 15 毫秒
1.
Maria G Papandreou Evdokia V Billis Emmanouel M Antonogiannakis Nikos A Papaioannou 《Journal of orthopaedic surgery and research》2009,4(1):2-9
Background
Anterior cruciate ligament (ACL) injury or reconstruction can cause knee impairments and disability. Knee impairments are related to quadriceps performance – accelerated reaction time (ART) – and disability to performance of daily living activities which is assessed by questionnaires such as the Lysholm knee score. The purposes of this study were to investigate the effect of cross exercise, as supplementary rehabilitation to the early phase of ACL reconstruction: a) on quadriceps ART at the angles 45°, 60° and 90° of knee flexion and, b) on the subjective scores of disability in ACL reconstructed patients. 相似文献2.
José A Pe?agarícano Nikos Papanikolaou Yulong Yan Emad Youssef Vaneerat Ratanatharathorn 《Radiotherapy and oncology》2005,76(1):72-78
BACKGROUND AND PURPOSE: Helical tomotherapy can eliminate the need for junction lines. The goal of this study is to evaluate tomotherapy in the delivery of CSA radiation and measurement of plan quality using physical parameters in comparing conventional (CSA-RT) and helical tomotherapy (CSA-TOMO) plans. PATIENTS AND METHODS: CSA-TOMO and CSA-RT plans were created for dosimetric comparison. Integral dose values were calculated. The ratios D50% (dose received by 50% of the organ at risk's volume) and D10% (dose received by 10% of the organ at risk's volume) were calculated representing large volumes and small volumes of organs at risk receiving significant dose. RESULTS: When considering D50% and D10%, CSA-TOMO has a dosimetric advantage over CSA-RT for most organs at risk. The body integral dose was higher for the CSA-TOMO plan by approximately 6.5%. CONCLUSIONS: Tomotherapy is a feasible alternative for treatment of CSA. Analysis shows that tomotherapy improves dose ratios over conventional radiation for most organs at risk. The impact of a small increase in whole body integral dose is unknown. Long-term follow-up will be needed to answer this question as others have argued of the possibility of increased risk of secondary malignancies due to delivery of radiotherapy with IMRT. 相似文献
3.
Nancy J Keuthen Nikos Makris John E Schlerf Brian Martis Cary R Savage Katherine McMullin Larry J Seidman Jeremy D Schmahmann David N Kennedy Steven M Hodge Scott L Rauch 《Neuropsychopharmacology》2007,61(3):374-381
BACKGROUND: Limited knowledge exists regarding the neurobiology of trichotillomania (TTM). Cerebellum (CBM) volumes were explored, given its role in complex, coordinated motor sequences. METHODS: Morphometric magnetic resonance imaging (MRI) scans were obtained for 14 female subjects with DSM-IV diagnoses of TTM and 12 age-, education-, and gender-matched normal control (NC) participants. Parcellation was performed utilizing a recently developed methodology to measure subterritory volumes of the CBM. Regions were defined based on knowledge of the structural and functional subunits of the CBM. RESULTS: As predicted, significant group differences were reported for CBM raw cortical volumes (p = .008) that survived correction for total brain volume (TBV; p = .037) and head circumference (HC; p = .011). A priori and post hoc group raw volume comparisons for CBM subterritories and functional clusters revealed many significant differences. However, most differences failed to withstand correction for total CBM volumes (TCV). Smaller volumes were consistently reported for the TTM versus NC cohorts. Total Massachusetts General Hospital Hair Pulling Scale (MGHHPS) scores were significantly inversely correlated with left primary sensorimotor cluster volumes (p = .008), with smaller volumes associated with more severe TTM symptoms. CONCLUSIONS: These findings implicate the CBM in the neurobiology of TTM, with reduced subterritory volumes reported for the TTM versus NC groups. 相似文献
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6.
Joseph Niezette Nikos Hadjichristidis Victor Desreux 《Macromolecular chemistry and physics.》1976,177(7):2069-2078
Trityl methacrylate was polymerized with 2,2′-azodiisobutyronitrile at 60°C in a homogeneous hexamethylphosphoric triamide (HMPT) solution. The isotactic microstrucutre found by NMR spectroscopy was less important for this polymer than for poly(trityl methacrylate) prepared in benzene, a precipitating medium. Some aspects of the hydrodynamic behaviour of poly(trityl methacrylate) were examined in HMPT at 25°C. Relations between the intrinsic viscosity, the root-mean-square end-to-end dimension, and the weight average molecular weight were established. The unperturbed dimension 〈r 〉1/2 was determined from viscosity and light scattering measurements using the well known extrapolation methods of Kurata-Stockmayer, Stockmayer-Fixman, Cowie, Inagaki-Kurata, and Baumann. Poly(trityl methacrylate) adopts a moderately expanded conformation in HMPT at 25°C. The correlation of the chain rigidity with the molar volume of the side group of polymethacrylic esters shows that poly(trityl methacrylate) has a higher chain rigidity than other polymethacrylates on account of the steric hindrance of the trityl group and of the strong interactions between the aromatic rings. 相似文献
7.
Nikos Pandis Sverre Heim Georgia Bardi Ingrid Idvall Nils Mandahl Felix Mitelman 《Genes, chromosomes & cancer》1993,6(1):51-57
Short-term cultures from 20 breast carcinomas were analyzed cytogenetically. A normal female chromosome complement was found in 4 cases. Clonal chromosome aberrations were detected in 16 tumors. In 10 tumors, multiple cytogenetic clones were found; in 2 cancers the clones were related, reflecting clonal evolution, but in the remaining 8 tumors the clones were cytogenetically unrelated, indicating clonal heterogeneity in the origin of the tumor parenchyma. Correlation analysis between karyotypic and pathologic parameters indicated that cases with complex karyotypes and/or cytogenetically unrelated clones, when compared with cases with a single simple karyotypic abnormality, were generally of higher histologic malignancy grade, had more mitoses in the histologic sections, and also more often had carcinoma in situ lesions in the same breast. © 1993 Wiley-Liss, Inc. 相似文献
8.
Walhovd KB Fjell AM Reinvang I Lundervold A Dale AM Eilertsen DE Quinn BT Salat D Makris N Fischl B 《Neurobiology of aging》2005,26(9):1261-70; discussion 1275-8
The effect of age was investigated in and compared across 16 automatically segmented brain measures: cortical gray matter, cerebral white matter, hippocampus, amygdala, thalamus, the accumbens area, caudate, putamen, pallidum, brainstem, cerebellar cortex, cerebellar white matter, the lateral ventricle, the inferior lateral ventricle, and the 3rd and 4th ventricle. Significant age effects were found for all volumes except pallidum and the 4th ventricle. Heterogeneous age responses were seen in that age relationships for cortex, amygdala, thalamus, the accumbens area, and caudate were linear, while cerebral white matter, hippocampus, brainstem, cerebellar white, and gray matter, as well as volume of the lateral, inferior lateral, and 3rd ventricles showed curvilinear relationships with age. In general, the findings point to global and large effects of age across brain volumes. 相似文献
9.
A membrane cofactor protein transgenic mouse model for the study of discordant xenograft rejection 总被引:1,自引:0,他引:1
Nikos Yannoutsos Jan N. M. IJzermans Clara Harkes Fred Bonthuis Chun-Yan Zhou David White Richard L. M. Marquet & Frank Grosveld 《Genes to cells : devoted to molecular & cellular mechanisms》1996,1(4):409-419
Background: In recent years, interest has been revived in the possibility of transplanting organs into humans from a phylogenetically disparate species such as the pig (xenotransplantation). Such discordant xenografts, however, are subject to hyperacute rejection (HAR) and activation of host complement plays a major role in this rejection. This problem may be solved through the use of transgenic technology by providing the grafted tissue with molecules that down-regulate the action of host complement.
Results: Transgenesis with a yeast artificial chromosome (YAC) was used to produce transgenic mice with the complete genomic gene of the human complement regulator membrane cofactor protein (MCP). Transgenic mice were obtained that exhibit full regulation of MCP as normally observed in humans. Hearts from these mice were shown to be significantly protected from HAR caused by human serum in an in vivo experimental procedure.
Conclusions: We conclude that MCP can protect discordant xenografts from HAR caused by human serum and that transgenic mice can be used effectively as in vivo models for the study of the role of human complement regulatory molecules in xenotransplantation. 相似文献
Results: Transgenesis with a yeast artificial chromosome (YAC) was used to produce transgenic mice with the complete genomic gene of the human complement regulator membrane cofactor protein (MCP). Transgenic mice were obtained that exhibit full regulation of MCP as normally observed in humans. Hearts from these mice were shown to be significantly protected from HAR caused by human serum in an in vivo experimental procedure.
Conclusions: We conclude that MCP can protect discordant xenografts from HAR caused by human serum and that transgenic mice can be used effectively as in vivo models for the study of the role of human complement regulatory molecules in xenotransplantation. 相似文献
10.
Morphometric microvascular characteristics predict prognosis in superficial and invasive bladder cancer 总被引:1,自引:0,他引:1
Korkolopoulou P Konstantinidou AE Kavantzas N Patsouris E Pavlopoulos PM Christodoulou P Thomas-Tsagli E Davaris P 《Virchows Archiv : an international journal of pathology》2001,438(6):603-611
Recent research has shown that neovascularization, quantitated by microvessel density (MVD), constitutes a strong prognostic indicator in patients with invasive urothelial carcinomas. These studies, however, have focused only on MVD as the only factor reflecting angiogenesis in transitional-cell carcinomas (TCCs). The objective of this report was to evaluate multiple morphometric microvascular characteristics besides MVD in superficial and muscle-invasive TCCs separately, to provide a better approach to the relationship between angiogenesis, clinicopathological parameters, and prognosis. Histologic sections from 115 TCCs [35 superficial (T1) and 80 muscle-invasive] were immunostained for CD31 and evaluated using image analysis for the quantitation of MVD, area, total vascular area, major axis length, minor axis length, perimeter, compactness, shape factor, and Feret diameter. Patients were followed-up until death (n=31) or for an average of 42.2 months (median 38.5 months). MVD increased with progressing T category (P=0.049) but area (P=0.033), major axis length (P=0.022), perimeter (P=0.043), and Feret diameter (P=0.042) were highest in T2 tumors. Area was the single independent predictor of adverse significance in T1 TCCs, whereas for muscle-invasive tumors, survival was independently predicted by MVD. Regarding disease-free survival in superficial tumors, the single significant independent parameter was compactness, whereas area was an independent favorable indicator of disease-free survival for patients with invasive TCCs. It is concluded that the prognostic significance of neovascularization is better assessed by area and shape-related morphometric characteristics, whereas MVD becomes influential only with regard to overall survival of patients with invasive tumors. 相似文献