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81.
Intelligibility scores with a modified rhyme test were obtained for normally hearing subjects and subjects with sensorineural hearing impairment using several commercial hearing aids. These hearing aids differed mainly in values of time constants of compression and of harmonic distortion during overshoots. In general, better performance was obtained for the shorter time constants of compression, but performance seemed also to be affected by the occurrence of higher levels of harmonic distortion and of peak-clipping during overshoots.  相似文献   
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Self-controlled hyperthermia is a non-invasive technique used to kill or destroy cancer cells while preserving normal surrounding tissues. We have explored bulk magnetic Ni-Si and Ni-Al alloys as a potential thermoseeds. The structural, magnetic and magnetocaloric properties of the samples were investigated, including saturation magnetisation, Curie temperature (TC), and magnetic and thermal hysteresis, using room temperature X-ray diffraction and magnetometry. The annealing time, temperature and the effects of homogenising the thermoseeds were studied to determine the functional hyperthermia applications. The bulk Ni-Si and Ni-Al binary alloys have Curie temperatures in the desired range, 316?K–319?K (43?°C–46?°C), which is suitable for magnetic hyperthermia applications. We have found that TC strictly follows a linear trend with doping concentration over a wide range of temperature. The magnetic ordering temperature and the magnetic properties can be controlled through substitution in these binary alloys.  相似文献   
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The pulmonary delivery of nanoparticles (NPs) is a promising approach in nanomedicine. For the efficient and safe use of inhalable NPs, understanding of NP interference with lung surfactant metabolism is needed. Lung surfactant is predominantly a phospholipid substance, synthesized in alveolar type II cells (ATII), where it is packed in special organelles, lamellar bodies (LBs). In vitro and in vivo studies have reported NPs impact on surfactant homeostasis, but this phenomenon has not yet been sufficiently examined. We showed that in ATII-like A549 human lung cancer cells, silica-coated superparamagnetic iron oxide NPs (SiO2-SPIONs), which have a high potential in medicine, caused an increased cellular amount of acid organelles and phospholipids. In SiO2-SPION treated cells, we observed elevated cellular quantity of multivesicular bodies (MVBs), organelles involved in LB biogenesis. In spite of the results indicating increased surfactant production, the cellular quantity of LBs was surprisingly diminished and the majority of the remaining LBs were filled with SiO2-SPIONs. Additionally, LBs were detected inside abundant autophagic vacuoles (AVs) and obviously destined for degradation. We also observed time- and dose-dependent changes in mRNA expression for proteins involved in lipid metabolism. Our results demonstrate that non-cytotoxic concentrations of SiO2-SPIONs interfere with surfactant metabolism and LB biogenesis, leading to disturbed ability to reduce hypophase surface tension. To ensure the safe use of NPs for pulmonary delivery, we propose that potential NP interference with LB biogenesis is obligatorily taken into account.  相似文献   
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Atypical meningiomas (AMs) and malignant meningiomas (MMs) are tumors with a lower incidence and poorer prognosis than benign meningiomas. The role of radiotherapy as an adjuvant to surgical resection, especially for AMs, is incompletely defined. In this study, the English-language literature was systematically reviewed for studies that reported tumor characteristics, treatment parameters, and clinical outcomes after adjuvant radiotherapy for AM and MM, including overall survival, progression-free survival, and/or time to recurrence or mortality. Clinical outcomes were further assessed in the context of resection status, timing of administration, and radiation dose. Outcomes after stereotactic radiosurgery were also examined. Treatment toxicity and other potential prognostic or confounding factors were appraised. Ten and 11 studies for AM and MM, respectively, met the inclusion criteria. The median 5-year progression-free survival and overall survival after adjuvant radiotherapy were 54.2% and 67.5%, respectively, for AM and 48% and 55.6% for MM. The complication rates were 11.1% for AM and 5.1% for MM. Incomplete resection and radiation dose <50 Gy conferred significantly poorer 5-year progression-free survival. Most studies were unable to demonstrate a statistically significant prognostic benefit for adjuvant radiotherapy in AM. In conclusion, adjuvant radiotherapy significantly improved local control of AMs and MMs, especially after subtotal resection. Study limitations, including inadequate statistical power, may underlie the studies'' inability to demonstrate a statistically significant benefit for adjuvant radiotherapy in AM. Because these tumors preferentially recur within 5 years of surgical resection, future studies should define whether early adjuvant therapy should become part of the standard treatment paradigm for completely excised tumors.  相似文献   
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Abstract

Endometriosis is currently considered as one of the most common diseases associated with infertility. A controversial issue is whether endometriosis per se exerts a detrimental effect on IVF outcomes. Failure of implantation due to endometriosis-associated infertility is a contradictory and widely discussed burden nowadays. The purpose of the study is to assess the quality of embryos and implantation rate in women with infertility associated with endometriosis. The study included infertile reproductive aged women, between 26 and 40 years who underwent IVF and ICSI procedures. The patients were divided into two groups: group I (n?=?70) involved 70 patients with recurrent unilateral endometriomas, II control group (n?=?50) with tubal factor infertility. The quality of the retrieved embryos was assessed according to the generally accepted classification of Gardner, indicating the rate of implantation in each group. Embryo transfer was performed in case of high quality embryos. Assessing the ovarian reserve indicators, in the group I patients with recurrent unilateral endometriomas the serum level of AMH was significantly lower (2.1?±?1.75 vs. 3.2?±?1.4, p?<?.005), as well as the number of retrieved oocytes (8.1?±?3.9 and 10.1?±?6.8, p?<?.005). The analysis of the results demonstrated that the duration of stimulation in the group patients with recurrent unilateral endometriomas was significantly higher in comparison with the group II (12.2?±?1.8 and 10.2?±?1.6 days, p?<?.001). Nevertheless, the number of good quality embryos retrieved was comparable in both groups (2.2?±?1.5 and 2.8?±?1.8). In the group I patients with recurrent unilateral endometriomas, there was a statistically significant decrease of implantation rate (17.1% vs. 24% p?<?.005). The results of the study revealed no statistical difference in embryo quality in the study cohort. However, it is important to note that a statistically significant difference in implantation rate in the group of endometriosis-associated infertility compared was obtained 1.5 times lower than in the control group (15.8% vs. 24.0% p?<?.005). The achieved results demonstrated an adverse IVF outcome in infertile women with recurrent endometrioma compared to the control group.  相似文献   
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