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排序方式: 共有1777条查询结果,搜索用时 15 毫秒
11.
C Cepollaro S Gonnelli C Pondrelli S Martini A Montagnani S Rossi L Gennari C Gennari 《Canadian Metallurgical Quarterly》1997,70(835):691-696
Measurement of ultrasonographic parameters provides information concerning not only bone density but also bone architecture. We investigated the usefulness of ultrasonographic parameters and bone mineral density for evaluating the probability of vertebral fracture. 397 postmenopausal women (59.1 +/- 6.0 years) with (n = 178) or without (n = 219) atraumatic vertebral fractures were studied. In all women, bone mineral density (BMD) of the lumbar spine was evaluated by dual X-ray absorptiometry (DXA) and speed of sound (SOS); broadband ultrasound attenuation (BUA) and Stiffness in the calcaneus were evaluated by an Achilles unit (Lunar Corporation). Ultrasonographic parameters and BMD were compared by examining the magnitude of the odds ratios, to determine which produces the highest estimate of the probability of odds of fracture, and by examining widths of the respective confidence intervals (CI) to show which estimate of odd ratio is the most precise. The relative risk of vertebral fracture, after adjusting for potential confounders, was 3.5 (CI 2.6-4.8) for BUA; 4.5 (CI 3.2-6.2) for SOS; 5.8 (CI 4.0-8.4) for Stiffness and 7.5 (CI 4.8-11.5) for BMD. Ultrasound (US) parameters were still significant independent predictors of vertebral fracture, even after adjusting for BMD. The relative risk of fracture for a simultaneous decrease by 1 SD of BMD and by 1 SD of each ultrasound parameter was 17.3 (CI 9.4-39.6) for BMD and SOS; 18.3 (CI 8.4-30.6) for BMD and BUA and 22.1 (CI 8.9-52.7) for BMD and Stiffness. Our data suggest that US and BMD provide complementary information which can be combined to improve estimates of vertebral fracture risk. 相似文献
12.
Juntunen Cindy L.; Atkinson Donald R.; Reyes Carla; Gutierrez Maria 《Canadian Metallurgical Quarterly》1994,31(2):327
Investigated whether (1) feminist identity development for women therapists was related to their use of feminist therapy behaviors (FTBs) and (2) feminist identity development and use of FTBs for women therapists were related to self-identification as a feminist therapist. 153 women psychologists (aged 30–77 yrs) were administered a women's issues in therapy questionnaire, which included a short version of the Feminist Identity Scale (FIS; K. M. Rickard, 1989, 1990). Ss were categorized into stages of feminine identity development according to their scores on 4 subscales of the FIS: Passive-Acceptance (PA), Revelation (REV), Embeddedness (EMB), and Synthesis (SYN). Ss scoring high on SYN and REV, and low on PA, reported greater use of FTBs; scores on the EMB were not related to the use of FTBs. All 4 subscales were predictive of women therapists who self-identified as feminist therapists. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
13.
Predd Joel Pfleeger Shari Lawrence Hunker Jeffrey Bulford Carla 《Security & Privacy, IEEE》2008,6(4):66-70
This column goes beyond previous insider analyses to identify a framework for a taxonomy of insider threats including both malicious and inadvertent actions by insiders that put organizations or their resources at some risk. The framework includes factors reflecting the organization, the individual, the information technology system, and the environment. 相似文献
14.
We present new tight bounds for evaluating the performance of sync word-based frame synchronization algorithms in the periodically embedded case. We consider antipodal signaling with coherent detection over additive white Gaussian noise and both optimal and suboptimal search techniques. Our bounds are very close to results obtained through simulation and tend asymptotically (for increasing signal-to-noise ratios) to the exact performance. 相似文献
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Electrochemical studies were carried out with disk electrodes of Invar (Fe-36%Ni) in phosphate solution at pH 6.0, using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) techniques, comparing the results with those for low carbon steel and pure Ni. Invar shows a reduced corrosion when compared to carbon steel in the weakly inhibitive solution though inferior to pure Ni. Phosphate anion is responsible for the formation of a protecting and stable film on the alloy surface at pH 6.0.Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) with Invar disk electrodes (Fe-36%Ni) in phosphate solutions at pH=6.0 were carried out. Results were compared with those of carbon steel and pure Ni. 相似文献
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Metastasis is the process whereby cancer cells migrate from the primary tumour site to colonise the surrounding or distant tissue or organ. Metastasis is the primary cause of cancer-related mortality and approximately half of all cancer patients present at diagnosis with some form of metastasis. Consequently, there is a clear need to better understand metastasis in order to develop new tools to combat this process. MicroRNAs (miRNAs) regulate gene expression and play an important role in cancer development and progression including in the metastatic process. Particularly important are the roles that miRNAs play in the interaction between tumour cells and non-tumoral cells of the tumour microenvironment (TME), a process mediated largely by circulating miRNAs contained primarily in extracellular vesicles (EVs). In this review, we outline the accumulating evidence for the importance of miRNAs in the communication between tumour cells and the cells of the TME in the context of the pre-metastatic and metastatic niche. 相似文献
19.
Annarita Falanga Valentina Del Genio Elizabeth A. Kaufman Carla Zannella Gianluigi Franci Marcus Weck Stefania Galdiero 《International journal of molecular sciences》2021,22(12)
Novel antiviral nanotherapeutics, which may inactivate the virus and block it from entering host cells, represent an important challenge to face viral global health emergencies around the world. Using a combination of bioorthogonal copper-catalyzed 1,3-dipolar alkyne/azide cycloaddition (CuAAC) and photoinitiated thiol–ene coupling, monofunctional and bifunctional peptidodendrimer conjugates were obtained. The conjugates are biocompatible and demonstrate no toxicity to cells at biologically relevant concentrations. Furthermore, the orthogonal addition of multiple copies of two different antiviral peptides on the surface of a single dendrimer allowed the resulting bioconjugates to inhibit Herpes simplex virus type 1 at both the early and the late stages of the infection process. The presented work builds on further improving this attractive design to obtain a new class of therapeutics. 相似文献
20.
Guimes Rodrigues Filho Leandra Cardoso Toledo Daniel Alves Cerqueira Rosana Maria Nascimento de Assunção Carla da Silva Meireles Harumi Otaguro Sizue Ota Rogero Ademar Benévolo Lugão 《Polymer Bulletin》2007,59(1):73-81
Summary In this article, cellulose acetate produced through the homogeneous acetylation of sugar cane bagasse cellulose was used to
produce membranes, using poly(ethyleneglycol) 600 (PEG 600) as an admixture. The membranes were characterized using water
flux measurements (Payne’s cup), differential scanning calorimetry (DSC) and neutral red uptake (cytotoxicity). The results
showed that PEG 600 acts as a crystallinity inductor and/or pore former in the cellulose acetate matrix. The induction of
crystallinity is important for this system since it had not been reported on the literature yet. The results also demonstrated
that the studied membranes present a nontoxic behavior. 相似文献