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991.
Muna Shrestha Helen Shi Mark Strohmeier Ales Medek 《Journal of pharmaceutical sciences》2021,110(4):1592-1600
Physical or chemical interactions between drug product (DP) components can occur during manufacturing and/or upon storage; and may alter DP shelf life and performance. In this work a new Powder X-ray Diffraction (PXRD) peak was observed in DP under accelerated storage conditions. Due to the complex drug product matrix (including API, polymer, fillers, super disintegrant and lubricant), it was challenging to pinpoint the component(s) responsible for the new peak. In addition to PXRD, other orthogonal techniques including Differential Scanning Calorimetry (DSC), thermogravimetric analysis (TGA), dynamic vapor sorption (DVS), Solid State Nuclear Magnetic Resonance (SSNMR) and Infrared (IR) spectroscopy were employed in this investigation to understand the root cause mechanistically. Specifically, multi nuclei SSNMR (1H, 23Na, 13C) was instrumental in delineating the components of the matrix. We identified the root cause to be an acid base reaction occurring in the DP, whereby sodium ion in sodium stearyl fumarate (SSF) is replaced by proton leading to SSF form conversion. We also identified commercially available SSF to be a hydrate that can dehydrate to an anhydrous form upon heating. In general, the same techniques can be used to investigate interactions of any multi component solid dosage forms. 相似文献
992.
URS是设备采购的重要技术资料,针对新版GMP规范要求,结合洗烘灌封联动分装线系统及无菌制药工艺特点制定相关URS。 相似文献
993.
For the drawbacks of the synthetic bandwidth method based on time-domain back projection, a novel synthetic bandwidth method based on frequency-domain back projection is proposed in this article for stepped-frequency synthetic aperture radar to improve the computation efficiency and to realize the automatic spatial spectra cutting. To give a direct and clear comprehension for wideband synthesizing in the spatial image space, the bandwidth and centre frequency for spatial image are defined for the first time. The simulation results validate the effectiveness of the proposed method. 相似文献
994.
Alexandra R. Vaughn BS Ashley K. Clark BS Raja K. Sivamani MD MS CAT Vivian Y. Shi MD 《Pediatric dermatology》2018,35(1):152-157
Circadian rhythm is a biological clock that controls a wide range of physiological functions throughout the body, including various skin functions. A 24‐h diurnal cycle, governed by an endogenous clock in the brain, largely controls cutaneous diurnal rhythm, which external factors, including temperature, humidity, diet, and stress, also modulate locally. Circadian rhythm influences cutaneous blood flow and properties of skin barrier function, such as transepidermal water loss and capacitance, and has important implications in atopic dermatitis (AD). This review explores how aberrations in circadian rhythm may play a role in the pathogenesis of AD and proposes implementation of chronotherapy to improve treatment outcomes in patients with AD. 相似文献
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G. Shi 《International journal of hyperthermia》2013,29(6):625-636
The design and performance of annular antenna arrays with reflectors is presented. Arrays with three shapes of reflectors are analysed and simulated. These include the corner reflector, the circular reflector and the elliptical reflector. Power-density distributions within the annular arrays with and without reflectors are obtained by using the FDTD method. Also, the image theory method is used to verify the FDTD results in one case. By comparing the power-density distribution pattern of all four of the array designs (three with different reflectors, one without reflector), it is readily seen in each case that the array with reflectors yields better power-efficiency than the array without reflectors and the elliptical reflector yields the best performance. Comparisons of each array are made using 4, 6 and 8 antennae in the annular array. By using the optimized results of the elliptical reflector, the requirement for the input-power level to each antenna is greatly reduced. 相似文献
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To summarize the clinicopathological features, therapeutic regimens, and outcomes for patients with primary testicular lymphoma (PTL), we retrospectively reviewed the medical records of 13 patients diagnosed with PTL between 2001 and 2012 at our hospital. Average age at diagnosis was 62.2 ± 13.9 years, and all patients presented with painless testicular swelling. Diffuse large B-cell lymphoma was the dominant histotype (69.2 %). All 13 patients were treated with inguinal orchiectomy and received chemotherapy and/or radiotherapy. Complete follow-up data were available for 10 patients with an average follow-up duration of 28.4 ± 30.9 months. Seven patients were evaluated as Ann Arbor stage I or II, and three as stage III or IV. Eight patients were found to have hypoechogenic and hypervascular signals in the testis on ultrasound examination. Complete remission was achieved in six patients, and four patients who were still undergoing chemotherapy during the last follow-up showed no signs of relapse. Of the 10 patients with complete follow-up records, three had relapses, which occurred in the CNS, epiglottis, and the nasal cavity. Time to relapse in these cases was 2, 7, and 11 months, respectively (3/10). The mean progression-free survival was 22.57 months (range 1.1–101.9 months). 相似文献
1000.