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Accurate non-word repetition (NWR) has been largely attributed to phonological memory, although the task involves other processes including speech production, which may confound results in toddlers with developing speech production abilities. This study is based on Hoff, Core and Bridges’ adapted NWR task, which includes a real-word repetition (RWR) condition. We tested 86 typically developing 2-year-olds and found relationships between NWR and both receptive and expressive vocabulary using a novel measure that controls for speech production by comparing contextually matched targets in RWR. Post hoc analyses demonstrated the influence of lexical and sublexical factors in repetition tasks. Overall, results illustrate the importance of controlling for speech production differences in young children and support a useful methodological approach for testing NWR.  相似文献   
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Breast Cancer Research and Treatment - Trastuzumab improves outcomes among patients with HER2-positive breast cancer but is associated with a risk of treatment-induced cardiotoxicity (TIC). It is...  相似文献   
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Murad KL  Mahany KL  Brugnara C  Kuypers FA  Eaton JW  Scott MD 《Blood》1999,93(6):2121-2127
We previously showed that the covalent modification of the red blood cell (RBC) surface with methoxypoly(ethylene glycol) [mPEG; MW approximately 5 kD] could significantly attenuate the immunologic recognition of surface antigens. However, to make these antigenically silent RBC a clinically viable option, the mPEG-modified RBC must maintain normal cellular structure and functions. To this end, mPEG-derivatization was found to have no significant detrimental effects on RBC structure or function at concentrations that effectively blocked antigenic recognition of a variety of RBC antigens. Importantly, RBC lysis, morphology, and hemoglobin oxidation state were unaffected by mPEG-modification. Furthermore, as shown by functional studies of Band 3, a major site of modification, PEG-binding does not affect protein function, as evidenced by normal SO4- flux. Similarly, Na+ and K+ homeostasis were unaffected. The functional aspects of the mPEG-modified RBC were also maintained, as evidenced by normal oxygen binding and cellular deformability. Perhaps most importantly, mPEG-derivatized mouse RBC showed normal in vivo survival ( approximately 50 days) with no sensitization after repeated transfusions. These data further support the hypothesis that the covalent attachment of nonimmunogenic materials (eg, mPEG) to intact RBC may have significant application in transfusion medicine, especially for the chronically transfused and/or allosensitized patient.  相似文献   
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Introduction

Humans are widely exposed to estrogenically active phthalates, parabens, and phenols, raising concerns about potential effects on breast tissue and breast cancer risk. We sought to determine the association of circulating serum levels of these chemicals (reflecting recent exposure) with mammographic breast density (a marker of breast cancer risk).

Methods

We recruited postmenopausal women aged 55 to 70 years from mammography clinics in Madison, Wisconsin (N = 264). Subjects completed a questionnaire and provided a blood sample that was analyzed for mono-ethyl phthalate, mono-butyl phthalate, mono-benzyl phthalate, butyl paraben, propyl paraben, octylphenol, nonylphenol, and bisphenol A (BPA). Percentage breast density was measured from mammograms by using a computer-assisted thresholding method.

Results

Serum BPA was positively associated with mammographic breast density after adjusting for age, body mass index, and other potentially confounding factors. Mean percentage density was 12.6% (95% confidence interval (CI), 11.4 to 14.0) among the 193 women with nondetectable BPA levels, 13.7% (95% CI, 10.7 to 17.1) among the 35 women with detectable levels below the median (<0.55 ng/ml), and 17.6% (95% CI, 14.1 to 21.5) among the 34 women with detectable levels above the median (>0.55 ng/ml; Ptrend = 0.01). Percentage breast density was also elevated (18.2%; 95% CI, 13.4 to 23.7) among the 18 women with serum mono-ethyl phthalate above the median detected level (>3.77 ng/ml) compared with women with nondetectable BPA levels (13.1%; 95% CI, 11.9 to 14.3; Ptrend = 0.07). No other chemicals demonstrated associations with percentage breast density.

Conclusions

Postmenopausal women with high serum levels of BPA and mono-ethyl phthalate had elevated breast density. Further investigation of the impact of BPA and mono-ethyl phthalate on breast cancer risk by using repeated serum measurements or other markers of xenoestrogen exposure are needed.  相似文献   
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From the lungs of two fatal cases and from the sputum of two non-fatal cases of atypical bronchopneumonia, a psittacosis-like virus was isolated by direct intranasal inoculation of mice. Intraperitoneal injection of the same human material into mice gave negative results. The virus has a relatively high virulence for mice by intranasal or intra-cerebral inoculation, but does not kill after intraperitoneal inoculation. Its virulence for Java ricebirds is low and it fails to produce a carrier state in mice and birds. Two cases showed an increase in complement-fixing antibodies to the new virus and to psittacosis. The virus is antigenically related to the viruses of meningopneumonitis and psittacosis by complement fixation and by active immunity tests in mice.  相似文献   
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A heterogenetic antibody showing fixation of complement with human liver and agglutination of sheep erythrocytes was found in certain cases of acute infective hepatitis. The antigen concerned in these reactions was apparently heat stable and alcohol soluble. Differences from other heterogenetic antigen-antibody systems have been noted. The possible relation of the heterogenetic antibody to liver damage was considered.  相似文献   
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