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Greg Reynolds Martin Wilson Andrew Peet Theodoros N Arvanitis 《Magnetic resonance in medicine》2006,56(6):1211-1219
The quantitation of metabolite concentrations from in vitro NMR spectra is hampered by the sensitivity of peak positions to experimental conditions. The quantitation methods currently available are generally labor intensive and cannot readily be automated. Here, an algorithm is presented for the automatic time domain analysis of high-resolution NMR spectra. The TARQUIN algorithm uses a set of basis functions obtained by quantum mechanical simulation using predetermined parameters. Each basis function is optimized by subdividing it into a set of signals from magnetically equivalent spins and varying the simulated chemical shifts of each of these groups to match the signal undergoing analysis. A novel approach to the standard multidimensional minimization problem is introduced based on evaluating the fit resulting from different permutations of possible chemical shifts, obtained from one-dimensional searches. Results are presented from the analysis of (1)H proton magic angle spinning spectra of cell lines illustrating the robustness of the method in a typical application. Simulation was used to investigate the biggest peak shifts that can be tolerated. 相似文献
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Bastiaan R Klarenbeek Alexander AFA Veenhof Elly SM de Lange Willem A Bemelman Roberto Bergamaschi Piet Heres Antonio M Lacy Wim T van den Broek Donald L van der Peet Miguel A Cuesta 《BMC surgery》2007,7(1):16
Backround
Diverticulosis is a common disease in the western society with an incidence of 33–66%. 10–25% of these patients will develop diverticulitis. In order to prevent a high-risk acute operation it is advised to perform elective sigmoid resection after two episodes of diverticulitis in the elderly patient or after one episode in the younger (< 50 years) patient. Open sigmoid resection is still the gold standard, but laparoscopic colon resections seem to have certain advantages over open procedures. On the other hand, a double blind investigation has never been performed. The Sigma-trial is designed to evaluate the presumed advantages of laparoscopic over open sigmoid resections in patients with symptomatic diverticulitis. 相似文献4.
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Aleksandr Kolchin Dmitrii Shuleiko Mikhail Martyshov Aleksandra Efimova Leonid Golovan Denis Presnov Tatiana Kunkel Victoriia Glukhenkaya Petr Lazarenko Pavel Kashkarov Stanislav Zabotnov Sergey Kozyukhin 《Materials》2022,15(10)
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
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Bleomycin (BLM) is an example of an anticancer drug that should be delivered into cytosol for its efficient therapeutic action. With this in mind, we developed octaarginine (R8)-modified fusogenic DOPE-liposomes (R8-DOPE-BLM). R8-modification dramatically increased (up to 50-fold) the cell-liposome interaction. R8-DOPE-liposomes were internalized via macropinocytosis and did not end up in the lysosomes. R8-DOPE-BLM led to a significantly stronger cell death and DNA damage in vitro relative to all controls. R8-DOPE-BLM demonstrated a prominent anticancer effect in the BALB/c mice bearing 4T1 tumors. Thus, R8-DOPE-BLM provided efficient intracellular delivery of BLM leading to strong tumor growth inhibition in vivo. 相似文献