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11.
Sericin, a protein waste product of the silk industry, was crosslinked with chitosan, and a chitosan–sericin conjugate (CS) was prepared, characterized and used to remove hexavalent chromium (Cr(vi)) ions and methyl orange (MO) dye from aqueous solutions. The CS was shown to effectively remove Cr(vi) ions and MO dye at maximum adsorption capacities (Langmuir) of 139 mg g−1 for Cr(vi) ions and 385 mg g−1 for MO dye. Moreover, the adsorption of both Cr(vi) ions and MO dye was highly pH dependent and varied under different experimental conditions. Cr(vi) ion and MO dye uptake by the CS was confirmed by attenuated total reflectance Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy (XPS) and energy dispersive spectrometry analysis. Additionally, XPS analysis of the Cr(vi)-loaded CS revealed that Cr(vi) was reduced to the less toxic Cr(iii). The CS was shown not only to be highly amenable to regeneration, but also to be able to effectively remove MO dye and Cr(vi) ions from a binary mixture.

Sericin, a protein waste product of the silk industry, was crosslinked with chitosan, and a chitosan–sericin conjugate (CS) was prepared, characterized and used to remove hexavalent chromium (Cr(vi)) ions and methyl orange dye from aqueous solutions.  相似文献   
12.
The idea that when we use a tool we incorporate it into the neural representation of our body (embodiment) has been a major inspiration for philosophy, science, and engineering. While theoretically appealing, there is little direct evidence for tool embodiment at the neural level. Using functional magnetic resonance imaging (fMRI) in male and female human subjects, we investigated whether expert tool users (London litter pickers: n = 7) represent their expert tool more like a hand (neural embodiment) or less like a hand (neural differentiation), as compared with a group of tool novices (n = 12). During fMRI scans, participants viewed first-person videos depicting grasps performed by either a hand, litter picker, or a non-expert grasping tool. Using representational similarity analysis (RSA), differences in the representational structure of hands and tools were measured within occipitotemporal cortex (OTC). Contrary to the neural embodiment theory, we find that the experts group represent their own tool less like a hand (not more) relative to novices. Using a case-study approach, we further replicated this effect, independently, in five of the seven individual expert litter pickers, as compared with the novices. An exploratory analysis in left parietal cortex, a region implicated in visuomotor representations of hands and tools, also indicated that experts do not visually represent their tool more similar to hands, compared with novices. Together, our findings suggest that extensive tool use leads to an increased neural differentiation between visual representations of hands and tools. This evidence provides an important alternative framework to the prominent tool embodiment theory.SIGNIFICANCE STATEMENT It is commonly thought that tool use leads to the assimilation of the tool into the neural representation of the body, a process referred to as embodiment. Here, we demonstrate that expert tool users (London litter pickers) neurally represent their own tool less like a hand (not more), compared with novices. Our findings advance our current understanding for how experience shapes functional organization in high-order visual cortex. Further, this evidence provides an alternative framework to the prominent tool embodiment theory, suggesting instead that experience with tools leads to more distinct, separable hand and tool representations.  相似文献   
13.

Background/Aims:

There are a limited number of studies including the impact of antiplatelet drugs use on hospital outcomes for nonvariceal upper gastrointestinal bleeding. The aim of this study was to determine the effect of anti-aggregant, anti-coagulant and non-steroidal anti-inflammatory drugs upon hospital outcomes in patients with peptic ulcer bleeding.

Materials and Methods:

The patients under treatment with antiaggregant, anticoagulant or non-steroidal anti-inflammatory drugs were categorized as exposed group (n = 118) and the patients who were not taking any of these drugs were categorized as non-exposed group (n = 81). We analyzed the data of drug intake, comorbid disease, blood transfusion, duration of hospital stay, Blatchford/total Rockall score and diagnosis of patients.

Results:

In total, 199 patients were included. Of these 59.3% (exposed group) were taking drugs. The patients in exposed group were significantly older than those in non-exposed group (62.9 ± 17.3 years; 55.5 ± 19.3 years, P = 0.005, respectively). Mean number of red blood cell units transfused (2.21 ± 1.51; 2.05 ± 1.87, P = 0.5), duration of hospital stay (3.46 ± 2.80 days; 3.20 ± 2.30 days, P = 0.532) and gastric ulcer rate (33% vs 23.4%, P = 0.172) were higher in exposed group than in non-exposed group but the differences were not statistically significant. Total Rockall and Blatchford scores of the patients were significantly higher in exposed group than in non-exposed group (3.46 ± 1.72 vs 2.94 ± 1.87, P = 0.045; 10.29 ± 3.15 vs 9.31 ± 3.40, P = 0.038).

Conclusıon:

Our study has shown that anticoagulants, antiaggregants and nonsteroidal anti-inflammatory drugs do not effect duration of hospital stay, red blood cell transfusion requirement and rebleeding for peptic ulcer bleeding.  相似文献   
14.
15.
Context: Endometrial cancer is associated with metabolic disturbances related to its underlying risk factors, including obesity and diabetes. Identifying metabolite biomarkers associated with endometrial cancer may have value for early detection, risk assessment, and understanding etiology. Objective: The objective of the study was to evaluate the reliable measurement of metabolites in epidemiological studies with nonstandardized blood collection; confirm previously reported correlations of metabolites with body size; and assess differences in metabolite levels between cases and controls. Design: This was the Polish Endometrial Cancer Study (2001-2003). Setting: This study was a population-based case-control study. Patients: Patients included 250 cases and 250 controls. Intervention: The intervention included the measurement of serum metabolite levels of 15 amino acids, 45 acylcarnitines, and nine fatty acids. Main Outcome Measure: The main outcome measure was endometrial cancer. Results: Body mass index was correlated with levels of valine (r = 0.26, P = 3.4 × 10(-5)), octenoylcarnitine (r = 0.24, P = 1.5 × 10(-4)), palmitic acid (r = 0.26, P = 4.4 × 10(-5)), oleic acid (r = 0.28, P = 9.9 × 10(-6)), and stearic acid (r = 0.26, P = 2.9 × 10(-5)) among controls. Only stearic acid was inversely associated with endometrial cancer case status (quartile 4 vs. quartile 1: odds ratio 0.37, 95% confidence interval 0.20-0.69, P for trend = 1.2 × 10(-4)). Levels of the C5-acylcarnitines, octenoylcarnitine, decatrienoylcarnitine, and linoleic acid were significantly lower in cases than controls (odds ratios ranged from 0.21 to 0.38). Conclusions: These data demonstrate that previously reported variations in metabolomic profiles with body mass index can be replicated in population-based studies with nonfasting blood collection protocols. We also provide preliminary evidence that large differences in metabolite levels exist between cases and controls, independent of body habitus. Our findings warrant assessment of metabolic profiles, including the candidate markers identified herein, in prospectively collected blood samples to define biomarkers and etiological factors related to endometrial cancer.  相似文献   
16.
Human cancers display substantial intratumoral genetic heterogeneity, which facilitates tumor survival under changing microenvironmental conditions. Tumor substructure and its effect on disease progression and relapse are incompletely understood. In the present study, a high-throughput method that uses neutral somatic mutations accumulated in individual cells to reconstruct cell lineage trees was applied to hundreds of cells of human acute leukemia harvested from multiple patients at diagnosis and at relapse. The reconstructed cell lineage trees of patients with acute myeloid leukemia showed that leukemia cells at relapse were shallow (divide rarely) compared with cells at diagnosis and were closely related to their stem cell subpopulation, implying that in these instances relapse might have originated from rarely dividing stem cells. In contrast, among patients with acute lymphoid leukemia, no differences in cell depth were observed between diagnosis and relapse. In one case of chronic myeloid leukemia, at blast crisis, most of the cells at relapse were mismatch-repair deficient. In almost all leukemia cases, > 1 lineage was observed at relapse, indicating that diverse mechanisms can promote relapse in the same patient. In conclusion, diverse relapse mechanisms can be observed by systematic reconstruction of cell lineage trees of patients with leukemia.  相似文献   
17.

Background

Graft pseudoaneurysm (PSA) following pancreatic transplantation (PT) is a rarely reported complication that has significant morbidity and mortality. Few case reports and small series of this complication exist.

Methods

Retrospective review of files of 106 patients who underwent PT at the Tel-Aviv Sourasky Medical center between 1995 and 2010. Accessible asymptomatic patients (n = 35) were referred for graft PSA screening using ultrasound-Doppler.

Results

Eight patients developed graft PSA (8 %). All had early posttransplant sepsis. PSA incidence among patients who had perioperative sepsis is 13 %. Three patients developed early postoperative PSA, presenting as massive abdominal bleeding requiring urgent laparotomy and graft resection. Five patients were diagnosed with late-onset graft PSA between 3 months and 11 years posttransplant: clinical presentations were massive gastrointestinal bleeding (n = 2), acute renal failure (n = 1), and asymptomatic finding on screening ultrasound-Doppler (n = 2, 6 % of screened patients).

Conclusions

PSA following PT occurs in 8 % of patients. Perioperative infection is a risk factor. Early PSAs present as massive intra-abdominal bleeding. PSA may develop years posttransplant, may be asymptomatic, but late rupture is possible and presents as gastrointestinal bleeding. We recommend screening of patients at risk with ultrasound Doppler for early detection and treatment of asymptomatic PSAs.  相似文献   
18.
Over the last decades, the disability movement has been advocating for a paradigmatic shift in how disability is perceived and managed: from a medical or individual perspective focusing on the person's body and mind to a social perspective emphasizing the context and barriers of disability. However, we still know little about the perceptions of helping professionals, particularly social workers who work closely with disabled people. Thus, the aim of the current study is to develop and validate a scale—Perceptions Toward Disability Scale (PTDS)—to measure how social workers view disability: as an individual or social category. This paper describes the three phases of the scale's construction. First, scale items were formulated and its content validity was examined. Next, a pilot of 30 social workers completed a questionnaire and an initial exploratory factor analysis was conducted. In the third and main phase, the final draft was completed in 2016 by 565 Israeli social work students to assess its psychometric properties. Both exploratory and confirmatory factorial validity and discriminant validity analyses were conducted. The results of a confirmatory factor analysis revealed two distinct factors: an individual perspective of disability comprised of eight items (α = 0.77) and a social perspective of disability comprised of ten (α = 0.66). Subsequent analyses supported the scale's discriminant validity as indicated by the lack of an association between the Attitude Toward Disabled Persons Scale (ATDP) and the social model subscale (r = .13, p = .19) and by the weak negative relation with the individual model subscale (r = ?.25, p = .01). These findings show that the PTDS possesses promising construct validity and provide support for its utility. This easy‐to‐administer instrument offers several practical benefits and can serve as a framework for further empirical research regarding social work practice with disabled people.  相似文献   
19.
ABSTRACT

This article discusses and illustrates the role and impact of the intersection of supervisors’ and supervisees’ social identities and the associated power and privilege within the context of supervision for trauma-informed practice. Based on current theoretical, empirical, and practice literature, challenges related to the supervisor’s and supervisee’s racial, ethnicity, gender, social class, and additional social affiliations are identified, as are strategies for addressing them within supervision for trauma-informed practice. A case example drawn from the authors’ experiences illustrates the importance of attending to intersectionality in trauma-informed supervision Suggestions for future research efforts are offered.  相似文献   
20.
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