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101.
Endoscopic ultrasonography is not required for staging malignant esophageal strictures that preclude the passage of a diagnostic gastroscope 下载免费PDF全文
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Muhammad U. Ghori Liam M. Grover Kofi Asare-Addo Alan M. Smith 《Pharmaceutical development and technology》2018,23(2):183-197
Swelling, erosion, deformation, and consolidation properties can affect the performance of cellulose ethers, the most commonly used matrix former in hydrophilic sustained tablet formulations. The present study was designed to comparatively evaluate the swelling, erosion, compression, compaction, and relaxation properties of the cellulose ethers in a comprehensive study using standardised conditions. The interrelationship between various compressional models and the inherent deformation and consolidation properties of the polymers on the derived swelling and erosion parameters are consolidated. The impact of swelling (Kw) on erosion rates (KE) and the inter-relationship between Heckel and Kawakita plasticity constants was also investigated. It is evident from the findings that the increases in both substitution and polymer chain length led to higher Kw, but a lower KE; this was also true for all particle size fractions regardless of polymer grade. Smaller particle size and high substitution levels tend to increase the relative density of the matrix but reduce porosity, yield pressure (Py), Kawakita plasticity parameter (b?1) and elastic relaxation. Both KW versus KE (R2?=?0.949–0.980) and Py versus. b?1 correlations (R2?=?0.820–0.934) were reasonably linear with regards to increasing hydroxypropyl substitution and molecular size. Hence, it can be concluded that the combined knowledge of swelling and erosion kinetics in tandem with the in- and out-of-die compression findings can be used to select a specific polymer grade and further to develop and optimize formulations for oral controlled drug delivery applications. 相似文献
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Nur Aziah Hanapi Ahmad Saifuddin Mohamad Arshad Jafri Malin Abdullah Tengku Sifzizul Tengku Muhammad Siti R. Yusof 《Journal of pharmaceutical sciences》2021,110(2):698-706
Neurotherapeutic potentials of Centella asiatica and its reputation to boost memory, prevent cognitive deficits and improve brain functions are widely acknowledged. The plant's bioactive compounds, i.e. asiaticoside, madecassoside and asiatic acid were reported to have central nervous system (CNS) actions, particularly in protecting the brain against neurodegenerative disorders. Hence, it is important for these compounds to cross the blood-brain barrier (BBB) to be clinically effective therapeutics. This study aimed to explore the capability of asiaticoside, madecassoside and asiatic acid to cross the BBB using in vitro BBB model from primary porcine brain endothelial cells (PBECs). Our findings showed that asiaticoside, madecassoside and asiatic acid are highly BBB permeable with apparent permeability (Papp) of 70.61 ± 6.60, 53.31 ± 12.55 and 50.94 ± 10.91 × 10?6 cm/s respectively. No evidence of cytotoxicity and tight junction disruption of the PBECs were observed in the presence of these compounds. Asiatic acid showed cytoprotective effect towards the PBECs against oxidative stress. This study reported for the first time that Centella asiatica compounds demonstrated high capability to cross the BBB, comparable to central nervous system drugs, and therefore warrant further development as therapeutics for the treatment of neurodegenerative diseases. 相似文献
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Ashley Woolbert Emily R. Calasanz Muhammad Nazim 《International journal of surgery case reports》2013,4(12):1061-1063
INTRODUCTIONLumbar herniation is uncommon, with traumatic etiology being rare. Traumatic lumbar hernias are usually caused by seatbelt injury in motor vehicle accidents. It is exceedingly uncommon to see lumbar hernias in an unrestrained passenger of a motor vehicle accident.PRESENTATION OF CASEWe present a case of a traumatic inferior lumbar hernia in a young woman who was an unrestrained driver of a vehicle involved in a high-speed collision, with multiple rollover and ejection. CT scans of the abdomen and pelvis suggested soft tissue injury involving muscles in the left lower posterior flank with traumatic herniation of the colon and small bowel. Emergent midline abdominal laparotomy confirmed herniation in the left lower quadrant. After abdominal closure, in the prone position, an extensive laceration over the left flank also confirmed herniation. Due to its dirty nature, the wound was irrigated, lavaged and covered with wound vacuum-assisted closure placement. The decision was made in favor of delayed elective hernia repair.DISCUSSIONLumbar hernias are usually caused by sudden force to the abdomen, leading to increased intra-abdominal pressure. This pressure combined with areas of weakness in the superior and/or inferior triangle lead to herniation. Uncommonly, the contents of lumbar hernias can strangulate or incarcerate leading to bowel obstruction. This can often be prevented by detection with CT and laparotomy.CONCLUSIONLumbar herniation of traumatic etiology is rare. Early detection with CT and/or exploratory laparotomy is important to avoid increases in size of the defect and bowel strangulation and incarceration. 相似文献
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Muhammad Khurram Khan Mohammed Zakariah Hafiz Malik Kim-Kwang Raymond Choo 《The Australian journal of forensic sciences》2018,50(5):525-542
Today, digital multimedia (audio, video, images) is a common evidential source in litigation and criminal justice proceedings, and, not surprisingly, multimedia forensics is an active research area. One particular challenge faced by multimedia forensic researchers is the lack of a comprehensive and publicly available data-set for evaluating existing and new algorithms. This paper presents a digital audio forensic data-set, designed to facilitate evaluation of audio forensic algorithms (e.g. microphone identification, acoustic environment identification and splice detection). This paper also briefly describes the data-collection settings, microphones, speakers, languages and notations used. Existing tamper-detection techniques rely on artefacts due to recording devices, codec and/or the acoustic environment in the audio in question. Experimental results show that the selected approaches achieved promising results. 相似文献
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