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91.
Abstract

We investigated chromosomal aberrations in meningiomas using newly developed comparative genomic hybridization (CGH) technique and compared the results with the proliferating potential of the tumors. This technique permits the entire genome to be surveyed in one session of experiments. Our results revealed chromosomal aberrations in 5 out of 10 (50%) of the tumor samples studied. Losses of the distal parts of chromosome 1p (5 out of 10) and 22q (3 out of 10) were the two most frequent chromosomal aberrations. Losses and/or gains in other regions were only sporadic. The MIB-1 staining indices (MIB-511 %) were 1.9 ± 0.9% (mean ± SD) in benign (n = 8)1 4.5% in atypical (n = 1)1 and 11.7% in anaplastic (n = 1) meningiomas. The comparison of MIB-51 between the tumors with (2.3 ± 0.6%) and without (7.6 ± 0.3%) chromosomal aberrations demonstrated a trend towards an increased MIB-51 in meningiomas with chromosomal aberrations (p < 0.07) by unpaired 5tudent1s t-test. This study suggests that alterations in chromosomes 1p and 22q could be a primary focus of further detailed assessment of tumorigenesis and in understanding the biological behavior of meningiomas. [Neural Res 1998; 20: 612-616]  相似文献   
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We compared the surface free energies and enamel bond strengths of single-step self-etch adhesives with and without an oxygen-inhibited layer. The adhesives were applied to the enamel surfaces of bovine incisors, light irradiated, and the oxygen-inhibited layer was either retained or removed with ethanol. The surface free energies and their components (γ(S)(LW), γ(S)(+), and γ(S)(-)) were determined by measuring the contact angles of three test liquids placed on the cured adhesives. The enamel bond strengths of specimens with and without the oxygen-inhibited layer were measured. For all surfaces, the value of the estimated surface tension component γ(S)(LW) was relatively constant. The value of the γ(S)(+) component increased slightly when the oxygen-inhibited layer was removed, whereas that of the γ(S)(-) component decreased significantly. The enamel bond strengths of the self-etch adhesives were significantly lower in the specimens without an oxygen-inhibited layer. The oxygen-inhibited layer therefore appeared to promote higher enamel bond strength.  相似文献   
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95.
IL-15 is thought to be involved in the pathogenesis of rheumatoid arthritis (RA). We found that IL-15 plays an important role in the development of murine collagen-induced arthritis (CIA). The incidence and severity of CIA were slightly decreased in IL-15 KO mice but were increased in IL-15 Tg mice compared with wild-type (WT) mice. The levels of type II collagen (CII)-specific IL-17 production were significantly increased in IL-15 Tg mice compared with WT mice with CIA. Expression of IL-23R was up-regulated in CD4(+) T cells in IL-15 Tg mice but down-regulated in IL-15 KO mice compared with WT mice. In correlation with the expression levels of IL-23R, IL-17 production by CD4(+) T cells in response to exogenous IL-23 was increased in IL-15 Tg mice compared with WT mice. Furthermore, exogenous IL-15 synergized with IL-23 to induce CII-specific IL-17 production by CD4(+) T cells in vitro. Taken together, these results indicate that IL-15 plays an important role in the progression of CIA through increasing antigen-specific IL-17 production by CD4(+) T cells.  相似文献   
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98.

Study design

Imaging study of thoracic spine.

Objective

The purpose of this study was to investigate dynamic alignment and range of motion (ROM) at all segmental levels of thoracic spine.

Summary of background data

Thoracic spine is considered to have restricted ROM because of restriction by the rib cage. However, angular movements of thoracic spine can induce thoracic compressive myelopathy in some patients. Although few previous studies have reported segmental ROM with regard to sagittal plane, these were based on cadaver specimens. No study has reported normal functional ROM of thoracic spine.

Methods

Fifty patients with cervical or lumbar spinal disease but neither thoracic spinal disease nor compression fracture were enrolled prospectively in this study (34 males, 16 females; mean age 55.4 ± 14.7 years; range 27–81 years). After preoperative myelography, multidetector-row computed tomography scanning was performed at passive maximum flexion and extension position. Total and segmental thoracic kyphotic angles were measured and ROM calculated.

Results

Total kyphotic angle (T1/L1) was 40.2° ± 11.4° and 8.5° ± 12.8° in flexion and extension, respectively (P < 0.0001). The apex of the kyphotic angle was at T6/7 in flexion. Total ROM (T1/L1) was 31.7° ± 11.3°. Segmental ROM decreased from T1/2 to T4/5 but increased gradually from T4/5 to T12/L1. Maximum ROM was at T12/L1 (4.2° ± 2.1°) and minimum at T4/5 (0.9° ± 3.0°).

Conclusions

Thoracic spine showed ROM in sagittal plane, despite being considered a stable region. These findings offer useful information in the diagnosis and selection of surgical intervention in thoracic spinal disease.  相似文献   
99.
Pretangles are cytoplasmic tau immunoreactivity in neurons without apparent formation of fibrillary structures. In Alzheimer disease, such tau deposition is considered to represent a premature state prior to fibril formation (AD‐pretangles), later to form neurofibrillary tangles and finally ghost tangles. This morphological evolution from pretangles to ghost tangles is in parallel with their profile shift from four repeat (4R) tau‐positive pretangles to three repeat (3R) tau‐positive ghost tangles with both positive neurofibrillary tangles in between. This complementary shift of tau profile from 4R to 3R suggests that these tau epitopes are represented interchangeably along tangle evolution. Similar tau immunoreactivity without fibril formation is also observed in corticobasal degeneration (CBD‐pretangles). CBD‐pretangles and AD‐pretangles share: (i) selective 4R tau immunoreactivity without involvement of 3R tau; and (ii) argyrophilia with Gallyas silver impregnation. However, CBD‐pretangles neither evolve into ghost tangles nor exhibit 3R tau immunoreactivity even at the advanced stage. Because electron microscopic studies on these pretangles are quite limited, it remains to be clarified whether such differences in later evolution are related to their primary ultrastructures, potentially distinct between AD and CBD. As double staining for 3R and 4R tau clarified complementary shift from 4R to 3R tau along evolution from pretangles to ghost tangles, double immunoelectron microscopy, if possible, may clarify similar profile shifts in relation to each tau fibril at the ultrastructural dimension. This will provide a unique viewpoint on how molecular (epitope) representations are related to pathogenesis of fibrillary components.  相似文献   
100.
Despite seasonal influenza vaccines having been routinely used for many decades, influenza A virus continues to pose a global threat to humans, causing high morbidity and mortality each year. The effectiveness of the vaccine is largely dependent on how well matched the vaccine strains are with the circulating influenza virus strains. Furthermore, low vaccine efficacy in naïve populations such as young children, or in the elderly, who possess weakened immune systems, indicates that influenza vaccines need to be more personalized to provide broader community protection. Advances in both vaccine technologies and our understanding of influenza virus infection and immunity have led to the design of a variety of alternate vaccine strategies to extend population protection against influenza, some of which are now in use. In this review, we summarize the progress in the field of influenza vaccines, including the advantages and disadvantages of different strategies, and discuss future prospects. We also highlight some of the challenges to be faced in the ongoing effort to control influenza through vaccination.  相似文献   
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