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71.
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Objective : To evaluate varying CT settings to visualize pediatric vascular stents in comparison to digital angiography (DA). Background : There is a great clinical interest in substituting noninvasive methods to follow up children with congenital heart disease after interventional treatment. Materials and Methods : CT studies in small children with transcatheter placed stents were reviewed, retrospectively. Furthermore, eight stents were implanted in tubes and partially obstructed. CT exams were performed on varying scanners (4 up to 64 slices) with corresponding tube settings. The effects of dose on image quality were evaluated regarding stent size, strut thickness, and in‐stent stenoses in comparison to DA. Results : Fourteen children with 28 implanted stents were identified. Significant differences between higher and lower radiation settings were not found, corresponding with the phantom, where moderate tube setting showed the best results. In vitro, there was an improvement with increasing number of detector rows, which resulted in a decrease of stent strut overestimation (295% down to 201%; P < 0.0001) and a better agreement with DA measurements for mild (78% up to 91%; P = 0.003) and moderate in‐stent stenoses (80% up to 99%; P = 0.0001). Conclusion : Higher radiation exposure settings did not improve image quality, suggesting that the exams could be performed at a lower radiation dose. © 2008 Wiley‐Liss, Inc.  相似文献   
73.
We report B.R.B., a bilingual Turkish–English speaker with deep dysphasia. B.R.B. shows the typical pattern of semantic errors in repetition with effects of lexicality and imageability on performance in both languages. The question we asked is whether language type (Turkish or English) or language status—that is, first acquired (L1) or second acquired (L2)—has a greater impact on performance. Results showed that repetition in L1 (Turkish) was better than that in L2 (English). We also observed effects of language status on oral reading, writing to dictation, and naming (spoken and written) with greater impairment to repetition than other tasks in both languages. An additional finding was that spoken-word translation in both directions was worse than written-word translation, and word class had an effect on translation from L1 to L2. We argue that interactive activation models of deep dysphasia could explain deep dysphasia in bilingual speakers and interactions between task and language, if the weighted connections that support language processing in L2 are assumed to be weaker, thus causing rapid phonological decay to have more impact on task performance in L2. Implications of the results for models of bilingual language processing are also considered.  相似文献   
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In livers of susceptible but self-curing C57BL/6 mice, intracellular Leishmania donovani infection enhanced Toll-like receptor 4 (TLR4) and TLR2 gene expression. In the liver, infected TLR4−/− mice showed reduced gamma interferon (IFN-γ), tumor necrosis factor (TNF), and inducible nitric oxide synthase (iNOS) mRNA expression, higher-level and slowly resolving infection, delayed granuloma formation, and little response to low-dose chemotherapy; in serum, the ratio of IFN-γ to interleukin 10 (IL-10) activity was decreased by 50%. In contrast, in TLR2−/− mice, control of liver infection, parasite killing, and granuloma assembly were accelerated and chemotherapy''s efficacy enhanced. In livers of infected TLR2−/− mice, mRNA expression was not increased for inflammatory cytokines or iNOS or decreased for IL-10; however, the serum IFN-γ/IL-10 ratio was increased 6.5-fold and minimal responses to IL-10 receptor blockade suggested downregulated IL-10. In established infection in wild-type mice, blockading TLR2 induced parasite killing and triggering TLR4 strengthened resistance and promoted chemotherapy''s effect. Thus, in experimental L. donovani infection in the liver, TLR4 signaling upregulates and TLR2 signaling downregulates macrophage antileishmanial activity, making both receptors potential therapeutic targets in visceral leishmaniasis for engagement (TLR4) or blockade (TLR2).  相似文献   
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The objective of this study was to compare the morphological and chemical composition of bone graft (BG) and coral graft (CG) as well as their osteogenic differentiation potential using rabbit mesenchymal stem cells (rMSCs) in vitro. SEM analysis of BG and CG revealed that the pores in these grafts were interconnected, and their micro-CT confirmed pore sizes in the range of 107-315 µm and 103-514 µm with a total porosity of 92% and 94%, respectively. EDS analysis indicated that the level of calcium in CG was relatively higher than that in BG. FTIR of BG and CG confirmed the presence of functional groups corresponding to carbonyl, aromatic, alkyl, and alkane groups. XRD results revealed that the phase content of the inorganic layer comprised highly crystalline form of calcium carbonate and carbon. Atomic force microscopy analysis showed CG had better surface roughness compared to BG. In addition, significantly higher levels of osteogenic differentiation markers, namely, alkaline phosphatase (ALP), Osteocalcin (OC) levels, and Osteonectin and Runx2, Integrin gene expression were detected in the CG cultures, when compared with those in the BG cultures. In conclusion, our results demonstrate that the osteogenic differentiation of rMSCs is relatively superior in coral graft than in bone graft culture system.  相似文献   
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79.

Objectives

To ascertain the prevalence, presentation, diagnosis, severity, and complications of HELLP syndrome.

Materials and Methods

This is a prospective observational study analyzing the conditions and the data of 24 cases of HELLP syndrome in a tertiary care hospital. The analysis was done for the demographic characteristics, presentation of these patients, complications associated, and the perinatal outcome.

Results

0.45 % of the patients admitted for delivery developed HELLP syndrome. Majority of the patients developed the condition in 30–36 weeks period of gestation, while five patients developed it in the postpartum period. The condition led to 12.5 % of maternal and 45.8 % of perinatal mortality.

Conclusion

HELLP syndrome is an important cause for maternal and perinatal morbidity and mortality.  相似文献   
80.
Periodontal bio‐repositories, which allow banking of clinically validated human data and biological samples, provide an opportunity to derive biomarkers for periodontal diagnosis, prognosis and therapeutic activities which are expected to improve patient management. This article presents the establishing of the Malaysian Periodontal Database and Biobank System (MPDBS) which was initiated in 2011 with the aim to facilitate periodontal research. Partnerships were established with collaborating centres. Policies on specimen access, authorship and acknowledgement policies were agreed upon by all participating centres before the initiation of the periodontal biobank. Ethical approval for the collection of samples and data were obtained from institutional ethics review boards. A broad‐based approach for informed consent was used, which covered areas related to quality of life impacts, genetics and molecular aspects of periodontal disease. Sample collection and processing was performed using a standardized protocol. Biobanking resources such as equipment and freezers were shared with the Malaysian Oral Cancer Database and Tissue Bank System (MOCDTBS). In the development of the MPDBS, challenges that were previously faced by the MOCDTBS were considered. Future challenges in terms of ethical and legal issues will be faced when international collaborations necessitate the transportation of specimens across borders.  相似文献   
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