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111.
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   
112.
OBJECTIVES: The Bcl-2 protein is an important regulator of the apoptotic cascade and promotes cell survival. Bcl-2 can also delay entry into the cell cycle from quiescence. In the present study, we used two isogenic human ovarian carcinoma cell lines, which expressed differential levels of Bcl-2 proteins, to demonstrate that Bcl-2 may regulate the growth rates of adenocarcinoma cells. METHODS: The growth rates of two isogenic ovarian cancer cell lines were determined by XTT assays and flow cytometry combined with PI staining. Bcl-2-overexpressing SKOV3 cells were modified to express a doxycycline-inducible anti-Bcl-2 single-chain antibody and the effects of Bcl-2 protein inhibition on cell proliferation and apoptosis were assessed. RESULTS: We demonstrate that Bcl-2 promotes the accumulation of proliferating carcinoma cells in S phase. The Bcl-2-overexpressing SKOV3 cell line proliferates markedly faster and shows delayed progression to G2M phase compared to its low Bcl-2-expressing counterpart SKOV3.ip1 cell line. Single-chain antibody-mediated inhibition of Bcl-2 in SKOV3 cells was associated with increased growth rates and more rapid cell cycle progression. Treatment with cisplatin resulted in more cells accumulating in S phase in Bcl-2-overexpressing SKOV3 cells, while the inhibition of Bcl-2 abolished delayed entry into G2M phase without affecting cisplatin-induced apoptosis. CONCLUSIONS: Our results suggest that, in ovarian cancer cells, Bcl-2 delays cell cycle progression by promoting accumulation of cells in S phase without affecting the rate of apoptosis. Thus, in addition to its known role at the G0/G1 checkpoint, we demonstrate for the first time that Bcl-2 also regulates the S phase.  相似文献   
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Objectives

To assess the risk of vertical transmission in HIV-infected pregnant women undergoing diagnostic amniocentesis, and to identify possible predictive factors.

Study design

This was a single center retrospective study. The records of 330 HIV-infected pregnant women booked in our antenatal clinic from 31 January 2001 to 31 January 2006 were analyzed. Women who actually underwent diagnostic amniocentesis (“amniocentesis performed” group) were compared to those eligible for amniocentesis but who did not undergo the procedure (“amniocentesis withheld” group).

Results

During the time period, 318 liveborn babies were delivered (9 HIV infected (2.8%)). Thirty-four women (35 fetuses) were eligible for diagnostic amniocentesis. Amniocentesis was performed in 11 (32.4%) of these women (12 fetuses, none infected among the 9 liveborns) and withheld in 23 (67.6%) women. Among the 19 liveborn babies in this latter group, 1 (5.3%) was infected. There was no statistical difference in vertical transmission rate between the whole cohort of HIV-infected pregnant women and the group of women eligible for amniocentesis; or between the women who actually had or did not have an amniocentesis.The women who did undergo amniocentesis all received highly active antiretroviral combination therapy with three drugs; all but two had an undetectable HIV viral load, only one had immunosuppression and none had HCV co-infection.

Conclusion

No vertical transmission was observed in a group of nine liveborn babies after amniocentesis performed in selected HIV-infected pregnant women. In the presence of high genetic risk during pregnancy, amniocentesis can be considered after proper patient counselling.  相似文献   
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Original 1CP powder was studied and it was founded that powder material partially consists of the amorphous phase, in which crystallization begins at 450 °C and ends at 575 °C. Selective laser melting parameters were investigated through the track study, and more suitable ones were found: laser power P = 90, 120 W; scanning speed V = 1200 mm/s. Crack-free columnar elements were obtained. The sample obtained with P = 90 W, contains a small amount of amorphous phase. X-ray diffraction of samples shows the presence of α-Fe(Si) and Fe2B. SEM-image analysis shows the presence of ordered Fe3Si in both samples. Annealed samples show 40% less microhardness; an annealed sample containing amorphous phase shows higher soft-magnetic properties: 2.5% higher saturation magnetization, 35% higher residual magnetization and 30% higher rectangularity coefficient.  相似文献   
118.
IntroductionDespite the high prevalence of malnutrition in patients at all levels of healthcare, early prevention and treatment of malnourished patients are often neglected and overlooked in clinical practice. The aim of this systematic literature review was to identify the factors considered most important by healthcare professionals in the identification and treatment of malnourished patients or those at risk of malnutrition.MethodsA systematic literature review of qualitative research was conducted. Documents published in scientific journals in English from 2011 to 2021 were searched in the PubMed (MEDLINE), CINAHL and ProQuest databases. The results were analysed with a thematic analysis of qualitative research findings.ResultsFrom the search set of 1010 results, 7 sources were included in the final analysis. Factors identified by health professionals as important in the identification and treatment of malnourished patients in clinical practice were grouped into five themes: unclear organizational structure; indefinite structure of nutritional care; poor continuity of nutritional care; lack of knowledge and skills of health professionals; lack of time and human resources.ConclusionsHealth policy must provide resources for nutritional care for patients at all levels of health care on the initiative of the highest professional bodies at the state level. To improve the nutritional care of patients in clinical practice, the management of health care institutions must promote and enable the professional and organizational establishment of clinical nutrition as a regular medical activity of the institution, develop clinical nutritional pathways, and promote evidence-based clinical practice and interprofessional collaboration.  相似文献   
119.
Childhood maladaptive aggression is associated with disrupted functional connectivity within amygdala-prefrontal circuitry. In this study, neural correlates of childhood aggression were probed using the intrinsic connectivity distribution, a voxel-wise metric of global resting-state brain connectivity. This sample included 38 children with aggressive behavior (26 boys, 12 girls) ages 8–16 years and 21 healthy controls (14 boys, 6 girls) matched for age and IQ. Functional MRI data were acquired during resting state, and differential patterns of intrinsic functional connectivity were tested in a priori regions of interest implicated in the pathophysiology of aggressive behavior. Next, correlational analyses tested for associations between functional connectivity and severity of aggression measured by the Reactive-Proactive Aggression Questionnaire in children with aggression. Children with aggressive behavior showed increased global connectivity in the bilateral amygdala relative to controls. Greater severity of aggressive behavior was associated with decreasing global connectivity in the dorsal anterior cingulate and ventromedial prefrontal cortex. Follow-up seed analysis revealed that aggression was also positively correlated with left amygdala connectivity with the dorsal anterior cingulate, ventromedial and dorsolateral prefrontal cortical regions. These results highlight the potential role of connectivity of the amygdala and medial prefrontal and anterior cingulate cortices in modulating the severity of aggressive behavior in treatment-seeking children.  相似文献   
120.
We report a case of unusual human anaplasmosis in the Amazon rainforest of French Guiana. Molecular typing demonstrated that the pathogen is a novel Anaplasma species, distinct to all known species, and more genetically related to recently described Anaplasma spp. causing infections in rainforest wild fauna of Brazil.  相似文献   
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