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101.
Ge2Sb2Te5 (GST225) looks to be a promising material for rewritable memory devices due to its relatively easy processing and high optical and electrophysical contrast for the crystalline and amorphous phases. In the present work, we combined the possibilities of crystallization and anisotropic structures fabrication using femtosecond laser treatment at the 1250 nm wavelength of 200 nm thin amorphous GST225 films on silicon oxide/silicon substrates. A raster treatment mode and photoexcited surface plasmon polariton generation allowed us to produce mutually orthogonal periodic structures, such as scanline tracks (the period is 120 ± 10 μm) and laser-induced gratings (the period is 1100 ± 50 nm), respectively. Alternating crystalline and amorphous phases at the irradiated surfaces were revealed according to Raman spectroscopy and optical microscopy studies for both types of structures. Such periodic modulation leads to artificial optical and electrophysical anisotropy. Reflectance spectra in the near infrared range differ for various polarizations of probing light, and this mainly results from the presence of laser-induced periodic surface structures. On the other hand, the scanline tracks cause strong conductivity anisotropy for dc measurements in the temperature range of 200–400 K. The obtained results are promising for designing new GST225-based memory devices in which anisotropy may promote increasing the information recording density.  相似文献   
102.
(1) Background: The purpose of the study was a retrospective, comparative assessment of complications of the surgical sentinel node biopsy (SNB) procedure in breast cancer using the radiotracer method and the SentiMag® method on groups of patients after 3.5 years of use. (2) Methods: The material was a group of 345 patients with primary surgical breast cancer who underwent the SNB procedure with the use of a radiotracer in combination with wide local excision (WLE), simple amputation (SA) with SNB and an independent SNB procedure in the period from May 2018 to January 2021 in the Department of Oncological Surgery. Of the patients who were monitored in the Hospital Outpatient Clinic, 300 were enrolled. The analyzed group was compared in terms of the occurrence of the same complications with the group of 303 patients also operated on in our center in the period from January 2014 to September 2017, in which SN identification was performed using the SentiMag® method. (3) Results: The most common complications found were sensation disorders in the arm, which occurred in 16 (14.1%) patients using the radiotracer method, SentiMag®-11 (9.9%). By comparing the complication rate between the methods with the radiotracer (n = 300) and SentiMag® (n = 303), no significant differences were found. (4) Conclusions: Sentinel node (SN) identification using the radiotracer method and the SentiMag® method are comparable diagnostic methods in breast cancer, with a low risk of complications.  相似文献   
103.
The aim of this article is to explore the reasons for seeking selected information on a food label, with particular emphasis on certain information about sugar. In order to meet the aim, in 2020, a survey was conducted among consumers aged 18–45. Predictive models (Logistic Regression) were developed for noticing “light” products and reading food labels. The results of our study indicate that consumers are mainly discouraged from reading label information by a large amount of information, the lack of time, and a general reluctance to be interested in label information. When it comes to the factors that lead people to read label information, the naturalness of the product, its organic origin, and physical activity are important. Moreover, respondents who declared that they noticed products on the market defined as “light” were those who were interested in the naturalness of the product, but also consumers declaring that they have nutritional knowledge. The results of the study indicate the need to intensify information campaigns in order to emphasize how important it is for consumers to read the information on food labels. The amount and complexity of information currently appearing on the food label may unfortunately discourage consumers from reading it, so it is important to continuously improve this form of communication with the consumer.  相似文献   
104.
IntroductionRecently introduced microUSB ultrasound probe, which can be connected to personal mobile device constitutes a new class of diagnostic pocket size imaging devices (PSID).The aim of this study was to assess the feasibility and clinical utility of real-time tele-echocardiography with the use such device.Material and methodsThe study group comprised 30 patients (18 men and 12 women; mean age: 54 ±14 years; mean body mass index: 27 ±6 kg/m2), admitted to various hospital departments (infectious diseases, internal medicine and cardiology). All patients underwent focused echocardiographic examination performed by an inexperienced operator using PSID and collaborating remotely in real-time with cardiologist by means of tele-consultation. Before commencing the examination, the operators underwent 1 h training in use of the PSID.ResultsIn most of patients PSID imaging provided sufficient diagnostic image quality. The dimensions of left ventricle, left atrium and the aorta obtained during the this examination showed good correlation with standard echocardiography (r = 0.89, r = 0.82, r = 0.92 respectively), but the correlation for TAPSE measurements was less pronounced (r = 0.52). The agreement in detection of pathologies (wall motion abnormalities, morphological and functional valvular abnormalities) between the tele-echocardiography and standard echocardiographic examination was good to very good (κ ranged from 0.648 to 0.823).ConclusionsPocket size imaging devices allows an inexperienced operator to perform a focused echocardiographic examination under a remote supervision of an experienced cardiologist. The introduction of new technology in the form of PSID with tele-echocardiography feature can revolutionize access to this imaging technique.  相似文献   
105.
ObjectivesObstructive sleep apnea (OSA) is a common condition closely related to obesity, insulin resistance, dyslipidemia, and cardiovascular disease. The aim of this study was to explore the possible relationship between OSA and proprotein convertase subtilisin/kexin type 9 (PCSK9).MethodsFull-night polysomnography was performed on 150 participants who were divided into three groups: controls, OSA patients on statin therapy, and OSA patients not on statin therapy. Biochemical markers, plasma low-density lipoprotein (LDL) and high-density lipoprotein (HDL) subclasses, and PCSK9 were determined.ResultsPCSK9 was highest in OSA patients on statins compared to the control group and to OSA patients not on statins (p = 0.036 and p = 0.039, respectively), after adjustment for body mass index (BMI). LDL diameter was greater in OSA patients not on statins compared to OSA patients on statins (p = 0.032). PCSK9 was highest in the group of patients with all three risk factors (diagnosed OSA, statins, BMI ≥25 kg/m<sup>2</sup>) compared to groups with no, one, and two risk factors (p = 0.031, p = 0.001, and p = 0.029, respectively). Presence of OSA, statin therapy, and BMI ≥25 kg/m<sup>2</sup> when combined were independently associated with higher levels of PCSK9 when adjusted for antihypertensive therapy, small dense LDL, and HDL 3c subclass (odds ratio = 2.849; interquartile range [1.026–7.912], p = 0.044).ConclusionStatin therapy was closely related to PCSK9. OSA along with obesity and statin use induces elevation of PCSK9.  相似文献   
106.
Background: Osteoprotegerin (OPG) is a molecule which belongs to the tumor necrosis factor receptor superfamily. OPG concentration is elevated in patients with left ventricle hypertrophy, heart failure and acute myocardial infarction. OPG concentrations rise in chronic kidney disease (CKD). The aim of this study was to investigate the association between OPG concentrations and cardiovascular complications, such as left ventricle hypertrophy, systolic and diastolic dysfunction of left ventricle and dysfunction of right ventricle in chronic kidney disease patients not treated with dialysis. The relation between OPG and the amount of pericardial fluid was also examined. Methods: One hundred and one men with CKD stage 3–5 not treated with dialysis were included in the study. Overhydration, body fat mass and lean body mass were measured using bioimpedance spectroscopy (BIS). Echocardiography was performed to evaluate the amount of pericardial fluid and to measure the thickness of the interventricular septum (IVS), systolic and diastolic function of left ventricle, as well as systolic function of right ventricle. Results: We observed a significant positive association between OPG and the thickness of the interventricular septum, the size of the left atrium (LA) and the presence of pericardial fluid. A negative relationship was observed between OPG and ejection fraction (EF). Conclusions: Our results suggest that OPG can be an independent marker of left ventricular hypertrophy, systolic and diastolic dysfunction of left ventricle and the presence of pericardial fluid in chronic kidney disease patients.  相似文献   
107.
Numerous studies show the beneficial effect of reduced oxygen on the culture of animal embryos in vitro. However, few similar studies have been carried out in humans, and the conclusions from these were contradictory. Using sibling human oocytes, a prospective study was carried out to analyse the effect of 5 and 20% oxygen on prolonged development of embryos. The outcomes measured were fertilization rate and proportion of morphologically optimal embryos, blastocysts and optimal blastocysts developing on day 5. The results were analysed separately for the group of IVF (n = 988 oocytes) and ICSI (n = 928 oocytes) cycles. It was found that low oxygen did not influence fertilization, but in comparison with 20% oxygen, it resulted in a significantly higher proportion of embryos being optimal on day 3 after IVF (59 versus 43.2%; P < 0.001) as well as after ICSI cycles (51.2 versus 28.5%; P < 0.001). In both methods, the lower oxygen concentration improved the blastulation rate (73.2 versus 63.1%; P < 0.05 and 67.4 versus 54.7%; P < 0.001) and increased the proportion of embryos reaching the stage of expanded blastocyst with normal inner cell mass on day 5 (31.1 versus 14.6%; P < 0.001 and 18.9 versus 11.4%; P < 0.01). The ratio of successful embryo development to optimal blastocyst stage on day 5 of culture, calculated for two oxygen concentrations, was 2.1 for IVF and 1.7 for ICSI, in favour of lower oxygen tension.  相似文献   
108.
Monocyte activity after stimulation by serum of women with endometriosis   总被引:1,自引:0,他引:1  
OBJECTIVES: Impairments of immune system play an important role in the development and pathogenesis of endometriosis. In affected women peritoneal macrophages are excessively activated, which is visible in an increased synthesis and release of macrophage-derived cytokines and growth factors. Monocytes are precursors of those cells in peripheral blood. The aim of the study was to evaluate the activity of monocyte from a healthy person, after stimulation by serum of women with endometriosis in cell culture conditions. The indicator of monocyte activity was the concentration of neopterin (NPT), produced by those cells. MATERIAL AND METHODS: Twenty nine women with endometriosis (mean age: 28.7+/-4.5 years) were included into this study. Among them were 18 women with moderate endometriosis (I and II stages according to AFS) and 11 women with advanced stages of the disease (III and IV stages according to AFS). Reference group consisted of fifteen healthy women (mean age: 27.4+/-5.3 years), with excluded endometriosis and other pathological disorders within the pelvis. Monocytes used in the study were isolated from peripheral blood of a healthy male and serum of women with endometriosis and control group. Monocytes were cultured in attendance of 15% and 30% serum of studied women. The concentration of NPT in the supernatants of culture was measured by enzyme-linked immunosorbent ELISA assay. RESULTS: The serum of women with endometriosis causes an increased concentration of NPT in supernatants, when comparing with serum of healthy women (p<0. 0001). The highest concentration was observed after stimulation by serum of women with advanced endometriosis. CONCLUSIONS: Serum of women with endometriosis can have an effect on monocyte activity, which is displayed in the increased synthesis and secreted of NPT.  相似文献   
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