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101.
This work shows a method to synthesize and encapsulate magnetic nickel nanocrystals into polymeric colloidal particles through miniemulsion polymerization. The nickel nanoparticles are produced by a thermal decomposition method in the presence of oleylamine and triphenylphosphine, which results in a hydrophobic surface. However, being compatible with the monomer does not ensure a successful encapsulation by miniemulsion polymerization, as the nickel nanoparticles are expelled from the polymer particles with increasing styrene conversion due to the poor adhesion interaction between the organic shells of the nickel nanoparticles and the polystyrene. Changing the hydrophobic polystyrene to a polymer with higher polarity such as poly(methyl methacrylate) proves to be efficient for encapsulation of nickel nanoparticles when employing a hydrophilic initiator. After encapsulation, these nanoparticles show magnetic response.

  相似文献   

102.
Irradiation is a major causative factor among the small subgroup of sarcomas with a known etiology. The prognosis of radiation‐induced sarcomas (RIS) is significantly worse than that of their spontaneous counterparts. The most frequent histological subtypes include undifferentiated pleomorphic sarcomas, angiosarcomas, and leiomyosarcomas. A high frequency of MYC amplifications in radiation‐induced angiosarcomas, but not in primary angiosarcomas, has recently been described. To investigate whether MYC amplifications are also frequent in RIS other than angiosarcomas, we analyzed the MYC amplification status of 83 RIS and 192 sporadic sarcomas by fluorescence in situ hybridization. We found significantly higher numbers of MYC amplifications in RIS than in sporadic sarcomas (P < 0.0001), especially in angiosarcomas, undifferentiated pleomorphic sarcomas, and leiomyosarcomas. Angiosarcomas were special in that MYC amplifications were particularly frequent and always high level, while other RIS showed low‐level amplifications. We conclude that MYC amplifications are a frequent feature of RIS as a group and may contribute to the biology of these tumors. © 2012 Wiley Periodicals, Inc.  相似文献   
103.
Clinical Oral Investigations - The objectives of this retrospective clinical study were to describe characteristics of crown fractures in permanent teeth and to investigate the survival of pulp...  相似文献   
104.
Clinical Oral Investigations - The objective of this study was to evaluate the diagnostic value of intraoperative frozen section analysis (IFSA) of tumor bed margins in patients with oral squamous...  相似文献   
105.
A new class of non-ionic amphiphiles is synthesized using a diaryl derivative of diglycerol as a central core and functionalizing it with long alkyl chains (C-12/C-15) and monomethoxy PEG moiety (Mn: 350/550) by following a chemo-enzymatic approach. The aggregation behavior of the amphiphiles in aqueous medium is studied by using dynamic light scattering (DLS) and fluorescence spectroscopy, whereas the size and morphology of the aggregates are studied by transmission electron microscopy (TEM). A hydrophobic dye, Nile red and a hydrophobic drug, nimodipine, are used to demonstrate the nano-carrier capability of these non-ionic amphiphilic systems and the results are compared with amphiphilic analogues obtained from the triaryl derivatives of triglycerol. The in vitro controlled release of the encapsulated dye is successfully carried out in the presence of immobilized Candida antarctica lipase (Novozym 435). Furthermore, cytotoxicity data is also collected which suggests that the amphiphiles are suitable for biomedical applications.

A new series of oligo-glycerol based amphiphiles have been synthesized for drug delivery.  相似文献   
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In patients awaiting lung transplantation (LTX), adequate gas exchange may not be sufficiently achieved by mechanical ventilation alone if acute respiratory decompensation arises. We report on 20 patients with life‐threatening hypercapnia who received extracorporeal CO2 removal (ECCO2‐R) by means of the interventional lung assist (ILA®, Novalung) as bridge to LTX. The most common underlying diagnoses were bronchiolitis obliterans syndrome, cystic fibrosis, and idiopathic pulmonary fibrosis, respectively. The type of ILA was pumpless arteriovenous or pump‐driven venovenous (ILA activve®, Novalung) in 10 patients each. ILA bridging was initiated in 15 invasively ventilated and five noninvasively ventilated patients, of whom one had to be intubated prior to LTX. Hypercapnia and acidosis were effectively corrected in all patients within the first 12 h of ILA therapy: PaCO2 declined from 109 (70–146) to 57 (45–64) mmHg, < 0.0001; pH increased from 7.20 (7.06–7.28) to 7.39 (7.35–7.49), < 0.0001. Four patients were switched to extracorporeal membrane oxygenation due to progressive hypoxia or circulatory failure. Nineteen patients (95%) were successfully transplanted. Hospital and 1‐year survival was 75 and 72%, respectively. Bridging to LTX with ECCO2‐R delivered by arteriovenous pumpless or venovenous pump‐driven ILA is feasible and associated with high transplantation and survival rates.  相似文献   
110.

Background and Purpose

Several risk scores have been developed to predict mortality in intracerebral hemorrhage (ICH). We aimed to systematically determine the performance of published prognostic tools.

Methods

We searched MEDLINE and EMBASE for prognostic models (published between 2004 and April 2014) used in predicting early mortality (<6 months) after ICH. We evaluated the discrimination performance of the tools through a random-effects meta-analysis of the area under the receiver operating characteristic curve (AUC) or c-statistic. We evaluated the following components of the study validity: study design, collection of prognostic variables, treatment pathways, and missing data.

Results

We identified 11 articles (involving 41,555 patients) reporting on the accuracy of 12 different tools for predicting mortality in ICH. Most studies were either retrospective or post-hoc analyses of prospectively collected data; all but one produced validation data. The Hemphill-ICH score had the largest number of validation cohorts (9 studies involving 3,819 patients) within our systematic review and showed good performance in 4 countries, with a pooled AUC of 0.80 [95% confidence interval (CI)=0.77-0.85]. We identified several modified versions of the Hemphill-ICH score, with the ICH-Grading Scale (GS) score appearing to be the most promising variant, with a pooled AUC across four studies of 0.87 (95% CI=0.84-0.90). Subgroup testing found statistically significant differences between the AUCs obtained in studies involving Hemphill-ICH and ICH-GS scores (p=0.01).

Conclusions

Our meta-analysis evaluated the performance of 12 ICH prognostic tools and found greater supporting evidence for 2 models (Hemphill-ICH and ICH-GS), with generally good performance overall.  相似文献   
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