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81.
82.
Layered double hydroxides (LDHs) with two-dimensional nanostructure are inorganic materials that have attractive advantages such as biocompatibility, facile preparation, and high drug loading capacity for therapeutic bioapplications. Since the intercalation chemistry of DNA molecules into the LDH materials were reported, various LDH nanohybrids have been developed for biomedical drug delivery system. For these reasons, LDHs hybridized with numerous therapeutic agents have a significant role in cancer imaging and therapy with targeting functions. In this review, we summarized the recent advances in the preparation of LDH nanohybrids for cancer therapeutic strategies including gene therapy, chemotherapy, immunotherapy, and combination therapy.  相似文献   
83.
Separation of hydrated cement paste from aggregate is a key technology to reduce the amount of radioactive concrete waste during the decommissioning process. If separated cement-paste portions can be recycled as a solidifying agent for other radioactive waste, the amount of radioactive concrete waste could be close to “zero”. A study was conducted to achieve circular economy in the area of concrete decommissioning and found it to be successfully used as a solidifying agent for immobilization of liquid radioactive waste. However, previous work used a process that requires large amounts of energy (heat treatment was applied to most of the concrete fraction) because the objective was to completely remove hydrated cement powder from the aggregate. In this work, the separation system was modified to increase energy efficiency (heat treatment was applied to separated powder only), but such a change decreased the surface area of the recycled cement powder due to a higher inclusion of aggregate powder. A relatively lower solution to binder ratio could have been achieved for the preparation of wasteform specimens, and as a result, a 28 day compressive strength of wasteform could have become higher, but the final leachability indices were lower than the results observed from previous work. The results from 28 day compressive strength, thermal cycling and 90 day leaching experiments met the acceptance criteria for wasteform, indicating that this modified system can also be used for immobilization of liquid radioactive waste to meet the “zero” production of concrete waste during the decommissioning of a nuclear power plant. It should be noted that accurate monitoring of aggregate content in recycled cement powder during production is important to maintain proper reactivity of recycled cement powder.  相似文献   
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Background/AimsThis study aimed to determine changes in endoscopist-driven sedation practices 5 years after the first nationwide survey in 2014 by the Korean Society of Gastrointestinal Endoscopy (KSGE).MethodsA 59-item survey covering current practices was electronically mailed to all members of the KSGE in 2019.ResultsIn total, 955 (12.8%) out of 7,486 questionnaires were returned. A total of 738 (77.7%) out of 955 respondents attended dedicated sedation education programs. The American Society of Anesthesiologists class was recorded by 464 (51.2%) out of 907 respondents. The recording rate was higher in respondents who completed sedation education (p=0.014) and worked in general or tertiary hospitals (p<0.001). Compared to that reported in the previous survey, the reported use of propofol was higher in 2019. The respondents had higher satisfaction scores for propofol-based sedation compared with midazolam monotherapy (p<0.001). The rates of oxygen supplementation (p<0.001) and oxygen saturation level monitoring (p<0.001) during sedative endoscopy were higher in 2019 than in the previous survey. A total of 876 (98.4%) out of 890 respondents reported a separate recovery bay, and 615 (70.5%) out of 872 respondents reported that personnel were assigned solely to the recovery bay.ConclusionsEndoscopist-driven sedation and monitoring practices in 2019 were significantly different than those in 2014. The respondents favored propofol-based sedation and utilized oxygen supplementation and monitoring of O2 saturation more frequently in 2019 than in 2014. (Gut Liver, Published online August 1, 2022)  相似文献   
86.
The phase changes in alkali-activated slag samples when exposed to supercritical carbonation were evaluated. Ground granulated blast furnace slag was activated with five different activators. The NaOH, Na2SiO3, CaO, Na2SO4, and MgO were used as activators. C-S-H is identified as the main reaction product in all samples along with other minor reaction products. The X-ray diffractograms showed the complete decalcification of C-S-H and the formation of CaCO3 polymorphs such as calcite, aragonite, and vaterite. The thermal decomposition of carbonated samples indicates a broader range of CO2 decomposition. Formation of highly cross-linked aluminosilicate gel and a reduction in unreacted slag content upon carbonation is observed through 29Si and 27Al NMR spectroscopy. The observations indicate complete decalcification of C-S-H with formation of highly cross-linked aluminosilicates upon sCO2 carbonation. A 20–30% CO2 consumption per reacted slag under supercritical conditions is observed.  相似文献   
87.
This study examined the relationship between the personal predisposing factors of patients and the severity of pressure injuries (PIs) developed during surgery. This retrospective cohort study collected 439 cases of peri‐operative PIs. Using binary logistic regression to identify the variables associated with PI severity, the effects of interactions between associated variables were then tested. The results of this study revealed that among the personal predisposing factors, only higher patient age (P = .001) and higher body mass index (P < .001) posed a greater risk of stage 2 PIs or higher. Among the surgery‐related facilitating factors, only patients who were placed in the prone position during surgery and patients who lost ≥1000 mL of blood during surgery were at greater risk of stage 2 PIs or higher, compared, respectively, to those placed in the supine position and those who lost ≤100 mL of blood. Furthermore, the amount of blood lost during surgery moderated the influence of age on PI severity. For elderly patients who are expected to lose a large blood volume during surgery or lose an immeasurable amount of blood due to the use of cardiopulmonary bypass, taking more precautionary measures to prevent PIs is recommended.  相似文献   
88.
Few studies have reported on the clinical utility of targeted next-generation sequencing (NGS) for breast cancer in Korea. We retrospectively reviewed the targeted NGS data of 219 patients with breast cancer who underwent surgical resection between August 2018 and April 2021. Here, we described the mutational profiles of breast cancer and examined their prognostic implications. The most frequently mutated gene was PIK3CA (n = 97/219, 44.3%), followed by TP53 (n = 79/219, 36.1%), AKT1 (n = 23/219, 10.5%), and GATA3 (n = 20/219, 9.1%). TP53 mutations were associated with aggressive histologic features. We followed up for 31 (range, 1–39) months and observed 11 (5.0%) recurrences: nine were TP53 mutant and two were TP53 wild-type. Multivariable analysis revealed that TP53 mutation was an independent prognostic factor for recurrence (p = 0.012). Although no drug is currently available for TP53 mutations, it is valuable to know the mutational status of TP53 for the precise management of breast cancer.  相似文献   
89.
The impact of changes in nutritional status during hospitalization on prognosis in patients with heart failure with preserved ejection fraction (HFpEF) remains unknown. We examined the association between changes in the Geriatric Nutritional Risk Index (GNRI) and prognosis during hospitalization in patients with HFpEF stratified by nutritional status on admission. Nutritional status did and did not worsen in 348 and 349 of 697 patients with high GNRI on admission, and in 142 and 143 of 285 patients with low GNRI on admission, respectively. Kaplan–Meier analysis revealed no difference in risk of the composite endpoint, all-cause death, or heart failure admission between patients with high GNRI on admission whose nutritional status did and did not worsen. In contrast, patients with low GNRI on admission whose nutritional status did not worsen had a significantly lower risk of the composite endpoint and all-cause death than those who did. Multivariable analysis revealed that worsening nutritional status was independently associated with a higher risk of the composite endpoint and all-cause mortality in patients with low GNRI on admission. Changes in nutritional status during hospitalization were thus associated with prognosis in patients with malnutrition on admission, but not in patients without malnutrition among those with HFpEF.  相似文献   
90.
ObjectiveTo investigate the agreement and reliability of estimating the volumes and normative percentiles (N%) of segmented brain regions among NeuroQuant (NQ), DeepBrain (DB), and FreeSurfer (FS) software programs, focusing on the comparison between NQ and DB.Materials and MethodsThree-dimensional T1-weighted images of 145 participants (48 healthy participants, 50 patients with mild cognitive impairment, and 47 patients with Alzheimer’s disease) from a single medical center (SMC) dataset and 130 participants from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) dataset were included in this retrospective study. All images were analyzed with DB, NQ, and FS software to obtain volume estimates and N% of various segmented brain regions. We used Bland–Altman analysis, repeated measures ANOVA, reproducibility coefficient, effect size, and intraclass correlation coefficient (ICC) to evaluate inter-method agreement and reliability.ResultsAmong the three software programs, the Bland–Altman plot showed a substantial bias, the ICC showed a broad range of reliability (0.004–0.97), and repeated-measures ANOVA revealed significant mean volume differences in all brain regions. Similarly, the volume differences of the three software programs had large effect sizes in most regions (0.73–5.51). The effect size was largest in the pallidum in both datasets and smallest in the thalamus and cerebral white matter in the SMC and ADNI datasets, respectively. N% of NQ and DB showed an unacceptably broad Bland–Altman limit of agreement in all brain regions and a very wide range of ICC values (-0.142–0.844) in most brain regions.ConclusionNQ and DB showed significant differences in the measured volume and N%, with limited agreement and reliability for most brain regions. Therefore, users should be aware of the lack of interchangeability between these software programs when they are applied in clinical practice.  相似文献   
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