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991.
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The normal structure of human feet is optimized for shock dampening during walking and running. Foot binding was a historical practice in China aimed at restricting the growth of female feet for aesthetic reasons. In a bound foot the shock‐dampening function normally facilitated by the foot arches is withdrawn, resulting in the foot functioning as a rigid extension of the lower leg. An interesting question inspiring this study regards the nature of adaptation of the heel bone to this nonphysiological function using the parameters of cancellous bone anisotropy and 3D fabric topology and a novel intertrabecular angle (ITA) analysis. We found that the trabecular microarchitecture of the normal heel bone, but not of the bound foot, adapts to function by increased anisotropy and preferred orientation of trabeculae. The anisotropic texture in the normal heel bone consistently follows the physiological stress trajectories. However, in the bound foot heel bone the characteristic anisotropy pattern fails to develop, reflecting the lack of a normal biomechanical input. Moreover, the basic topological blueprint of cancellous bone investigated by the ITA method is nearly invariant in both normal and bound foot. These findings suggest that the anisotropic cancellous bone texture is an acquired characteristic that reflects recurrent loading conditions; conversely, an inadequate biomechanical input precludes the formation of anisotropic texture. This opens a long‐sought‐after possibility to reconstruct bone function from its form. The conserved topological parameters characterize the generic 3D fabric of cancellous bone, which is to a large extent independent of its adaptation to recurrent loading and perhaps determines the mechanical competence of trabecular bone regardless of its functional adaptation. © 2017 The Authors. Journal of Bone and Mineral Research Published by Wiley Periodicals Inc.  相似文献   
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Phase 1 testing of SGN-30, a chimeric monoclonal antibody for the treatment of CD30(+) malignancies, was conducted in a multicenter study. To explore the safety profile and establish the maximum tolerated dose (MTD), 24 patients with refractory or relapsed Hodgkin lymphoma or CD30(+) non-Hodgkin lymphoma received 6 weekly doses of intravenous SGN-30 at 4 dose levels (2, 4, 8, or 12 mg/kg). Serum concentrations of SGN-30 rose rapidly and were dose dependent. Adverse events were mild, with nausea, fatigue, and fever attributed to study treatment. One episode of hypersensitivity rash was reported. The MTD was not reached. Serious adverse events included herpes zoster (n = 2), influenza, and pneumonia. One patient with cutaneous anaplastic large cell lymphoma (8 mg/kg) achieved a complete response. Six patients, of whom 4 had Hodgkin lymphoma, achieved stable disease with durations ranging from 6 to 16 months. The pharmacokinetic profile of SGN-30 showed a biphasic disposition, and estimated half-lives ranging between 1 to 3 weeks. The 6 weekly infusions of SGN-30 resulted in approximately 2- to 3-fold accumulation in serum exposures consistently across the dose range. These results demonstrate that weekly administration of SGN-30 is safe and has modest clinical activity in patients with CD30(+) tumors. This trial is registered at http://www.ClinicalTrials.gov as no. NCT00051597.  相似文献   
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There is now a large amount of evidence indicating that women with extensive areas of mammographic densities are 4-6 times more likely to develop breast cancer than those with little or no density in the mammogram. We have examined one potential biological explanation for this association by estimating the incidence of various histological types of benign breast disease in relation to mammographic density. We studied the large cohort of women taking part in the National Breast Screening Study (NBSS), a randomized trial of screening with mammography. Mammograms from subjects with biopsies (n = 423) and from a comparison group of subjects randomly selected from the NBSS (n = 465) were included. Histological slides from biopsied subjects (n = 353) were classified independently by the pathologists of the NBSS and by a review pathologist (H.M.J.). Mammographic density in more than 75% of the breast area was associated with an increased risk of incidence of hyperplasia without atypia, and of atypical hyperplasia and/or carcinoma in situ. The classifications of the review pathologist showed that, compared to women with no density, the relative risk of incident lesions for women with density in more than 75% of breast was 13.85 (95% CI 2.65-72.49) for hyperplasia, and 9.23 (95% CI 1.66-51.48) for atypical hyperplasia and/or carcinoma in situ. These findings suggest that the association between extensive mammographic density and breast cancer risk may, at least in part, be attributable to biological processes in the breast that give rise to these histological features that are known to be related to breast cancer risk.  相似文献   
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Accuracy of intraoperative frozen-section analysis of axillary nodes.   总被引:2,自引:0,他引:2  
G R Hingston  T G Cooke  J J Going  R Simon  M M Flet 《The British journal of surgery》1999,86(8):1092; author reply 1092-1092; author reply 1093
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1000.
Interleukin-13 prevents autoimmune diabetes in NOD mice.   总被引:1,自引:0,他引:1  
Interleukin (IL)-13 is a cytokine primarily produced by the T-helper (Th)-2 subset of lymphocytes that possesses powerful anti-inflammatory properties. Here, we have evaluated the impact of IL-13 treatment on development of type 1 diabetes in diabetes-prone nonobese diabetic (NOD) mice. Prolonged treatment with recombinant human IL-13 (hIL-13) markedly diminished the incidence of spontaneous type 1 diabetes in the mice. Female NOD mice treated from age 5-16 weeks with hIL-13 also showed significantly milder insulitis than control mice. The preventive action of hIL-13 was associated with a slight but significant change from a type 1 to a type 2 cytokine response. Accordingly, splenic lymphoid cells (SLC) from hIL-13-treated mice secreted less interferon (IFN)-gamma upon ex vivo stimulation with Concanavalin A than controls, and anti-CD3 monoclonal antibody-induced activation of T-cells in vivo resulted in lower blood levels of IFN-gamma and tumor necrosis factor-alpha and augmented blood levels of IL-4 in NOD mice pretreated with hIL-13. hIL-13 treatment also increased the blood levels of IgE and inhibited the transfer of type 1 diabetes by spleen cells from a diabetic donor to irradiated recipients. Taken together, these data add hIL-13 to the list of cytokines capable of downregulating immunoinflammatory diabetogenic pathways in NOD mice, and further support the concept that IL-4-related anti-inflammatory cytokines might have a role in the prevention of type 1 diabetes.  相似文献   
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