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71.
Fetal therapy raises ethical concerns in relation to the balance of potential benefit and harm, autonomy and informed consent, and the duties of the clinician to the pregnant women and fetus. Invasive therapy should be recommended only when it has a realistic chance of saving the life of the fetus and offspring or preventing serious and irreversible disease or disability. Clinicians should respect maternal choice and assessment of risk, particularly if the therapy might be only partially successful, leaving the offspring with a profound morbidity. Fetal therapy should not be undertaken without maternal consent; nor should it be presented coercively as an option to avoid a termination of pregnancy. Therapeutic procedures of unproven efficacy should be undertaken only with the voluntary informed consent of the pregnant woman and according to a clearly defined research protocol that has been approved by an appropriate research ethics committee and where appropriate support and counselling can be provided. 相似文献
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L F Wockner E P Noble B R Lawford R McD Young C P Morris V L J Whitehall J Voisey 《Translational psychiatry》2014,4(1):e339
Recent studies suggest that genetic and environmental factors do not account for all the schizophrenia risk, and epigenetics also has a role in disease susceptibility. DNA methylation is a heritable epigenetic modification that can regulate gene expression. Genome-wide DNA methylation analysis was performed on post-mortem human brain tissue from 24 patients with schizophrenia and 24 unaffected controls. DNA methylation was assessed at over 485 000 CpG sites using the Illumina Infinium HumanMethylation450 Bead Chip. After adjusting for age and post-mortem interval, 4641 probes corresponding to 2929 unique genes were found to be differentially methylated. Of those genes, 1291 were located in a CpG island and 817 were in a promoter region. These include NOS1, AKT1, DTNBP1, DNMT1, PPP3CC and SOX10, which have previously been associated with schizophrenia. More than 100 of these genes overlap with a previous DNA methylation study of peripheral blood from schizophrenia patients in which 27 000 CpG sites were analysed. Unsupervised clustering analysis of the top 3000 most variable probes revealed two distinct groups with significantly more people with schizophrenia in cluster one compared with controls (P=1.74 × 10−4). The first cluster composed of 88% of patients with schizophrenia and only 12% controls, whereas the second cluster composed of 27% of patients with schizophrenia and 73% controls. These results strongly suggest that differential DNA methylation is important in schizophrenia etiology and add support for the use of DNA methylation profiles as a future prognostic indicator of schizophrenia. 相似文献
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Daqian Wang Ji Qi Baoru Huang Elizabeth Noble Danail Stoyanov Jun Gao Daniel S. Elson 《Biomedical optics express》2022,13(4):2364
Smoke generated during surgery affects tissue visibility and degrades image quality, affecting surgical decisions and limiting further image processing and analysis. Polarization is a fundamental property of light and polarization-resolved imaging has been studied and applied to general visibility restoration scenarios such as for smog or mist removal or in underwater environments. However, there is no related research or application for surgical smoke removal. Due to differences between surgical smoke and general haze scenarios, we propose an alternative imaging degradation model by redefining the form of the transmission parameters. The analysis of the propagation of polarized light interacting with the mixed medium of smoke and tissue is proposed to realize polarization-based smoke removal (visibility restoration). Theoretical analysis and observation of experimental data shows that the cross-polarized channel data generated by multiple scattering is less affected by smoke compared to the co-polarized channel. The polarization difference calculation for different color channels can estimate the model transmission parameters and reconstruct the image with restored visibility. Qualitative and quantitative comparison with alternative methods show that the polarization-based image smoke-removal method can effectively reduce the degradation of biomedical images caused by surgical smoke and partially restore the original degree of polarization of the samples. 相似文献
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Ian Brissette Ann Lowenfels Corina Noble Deborah Spicer 《Journal of nutrition education and behavior》2013,45(5):404-411
ObjectiveTo examine purchase patterns at fast-food restaurants and their relation to restaurant characteristics, customer characteristics, and use of calorie information.DesignCross-sectional survey.SettingFast-food restaurants in New York State.ParticipantsAdult fast-food restaurant customers (n = 1,094).Variables MeasuredRestaurant characteristics (fast-food chain type, presence of calorie labels, and poverty of location), participant characteristics (demographics, calorie knowledge, awareness, and use), and customer purchasing patterns (ordering low-calorie or no beverage, small or no fries, or < 3 items) were used as predictors of total calories purchased.AnalysisMultiple regression.ResultsIn a regression model including restaurant and customer characteristics, fast-food chain customer age, sex, calorie use, and calorie awareness were independently associated with total calories purchased (all P < .05; model R2 = .19). When 3 purchasing patterns were added to the model, calorie use (P = .005), but not calorie awareness, remained associated with total calories purchased. The 3 purchase patterns collectively accounted for the majority of variance in calorie totals (Δ model R2 = .40).Conclusions and ImplicationsPromoting use of calorie information, purchase strategies, and calorie awareness represents complementary ways to support lower-calorie choices at fast-food chains. 相似文献
76.
An enzyme-linked immunosorbent assay has been developed for the quantitation of activated Hageman factor-C1 inactivator (HF-C1 INH) complexes. Addition of increasing quantities of either of the major forms of activated Hageman factor (HFa or HFf) to normal plasma or to Hageman factor-deficient plasma leads to a dose-dependent increase in activated HF-C1 INH complexes. As little as 0.5 micrograms/mL of activated HF added to plasma can be detected, corresponding to activation of approximately 2% of plasma HF. The sensitivity of the assay is increased at least tenfold when complexes are formed in HF- deficient plasma, indicating competition between unactivated HF and activated HF-C1 INH complexes for binding to the antibody. Specificity is demonstrated in that addition of activated HF to hereditary angioedema plasma yields less than 1% of the activated HF-C1 INH complex formation obtained with normal plasma. Kaolin activation of HF- deficient plasma yields no detectable complex formation. Kaolin activation of prekallikrein-deficient plasma demonstrates a time- dependent increase in formation of activated HF-C1 INH complex consistent with the ability of HF in this plasma to autoactivate as the time of incubation with the surface is increased. Kaolin treatment of high-molecular weight (HMW) kininogen-deficient plasma yields an even more profound abnormality in the rate of formation of activated HF-C1 INH complexes reflecting the complex role of HMW kininogen in the initiation of contact activation. Although addition of corn inhibitor to plasma prevents activated HF-C1 INH complex formation, it does not inhibit activated HF sufficiently fast to prevent prekallikrein activation. 相似文献
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A case of mixed connective tissue disease (MCTD) is presented in which mediastinal lymphadenopathy was the most prominent radiological finding detected by plain chest radiographs and computed tomography. Pulmonary arterial hypertension, which is a rare and often fatal complication of MCTD, also developed in this patient. 相似文献