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1.
Cardiovascular and noncardiovascular conditions are commonly encountered in the emergency department. While the majority of patients have underlying cardiovascular aetiologies, such as acute myocardial infarction, congestive heart failure, aortic dissection and pulmonary embolism, a small subset of patients have underlying noncardiovascular conditions, although they present with similar symptoms of chest pain, dyspnoea, cough, haemoptysis and haematemesis. This article aims to describe the imaging findings in common noncardiovascular conditions of the chest that are frequently encountered in the emergency department, with a review of the existing literature.  相似文献   
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Brain cyclooxygenases (COX), the rate-limiting enzyme in prostaglandin synthesis, is rapidly and transiently induced by convulsions in hippocampal and cortical neurons. Previous studies have explored the protective effect of naproxen (non-selective COX-inhibitor) or rofecoxib (selective COX-2 inhibitor) against chemical kindling in mice. With this background, the present study was designed to explore the possible effect of nimesulide (a preferential COX-2 inhibitor) against pentylenetetrazol (PTZ)-induced kindling epilepsy in mice. To induce kindling, PTZ was injected in a subconvulsive dose (40 mg/kg, i.p.) every other day for 15 days. Nimesulide (2.5 or 5 mg/kg, p.o.) was administered each day 45 min before either PTZ or vehicle challenge. The intensity of kindling was assessed immediately after PTZ administration according to a prevalidated scoring scale. On 16th day i.e. 24 h after the last dose of PTZ, animals were sacrificed and various biochemical parameters were assessed in the whole brain. Compared with normal control group, PTZ-kindled mice had significantly higher levels of malondialdehyde, nitrite, myeloperoxidase but had lower levels of reduced glutathione in the whole brain homogenate. Chronic treatment with nimesulide (2.5 or 5 mg/kg, p.o.) for 15 days showed significant decrease in kindling score and could play a role in controlling the accompanying biochemical alterations due to PTZ. These results suggested that nimesulide, a preferential COX-2 inhibitor offered neuroprotection against PTZ-induced kindling in mice.  相似文献   
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Background: Ingestion of coins is a common clinical problem in children. Many of the coins are ferromagnetic and can be retrieved with the help of a magnet. We describe the use of a novel endoscopic accessory for removing ferromagnetic coins. Material and methods: Two magnet discs of 1.5 cm diameter were joined to a 200 cm steel wire of 0.75 mm thickness with a terminal 5 cm spring. A Teflon tube (160 cm, 7 F) was used along with this instrument as a sleeve. The use of this accessory was analyzed prospectively in subjects presenting with a history of coin ingestion. The time taken for removal of coins, complications during the procedure and failure rate was noted. Effect of the magnet on cardiac rhythm was also noted during the procedure. Results: A total of 55 children (mean age 5.1 ± 2.3 years) with coin ingestion presented over a period of 1 year. Forty‐four coins were ferromagnetic. All ferromagnetic coins were removed successfully. Mean time for removal was 68 ± 22 s. No complications were encountered. Conclusion: The novel magnetic instrument is precise, safe and quick for the removal of ferromagnetic coins under direct vision.  相似文献   
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Summary: Hydrophobically modified poly(acrylic acid) was synthesized using 3‐pentadecylcyclohexylamine (3‐PDCA), which was in turn synthesized from 3‐pentadecylphenol, one of the components of cashew‐nut shell liquid (CNSL), a renewable resource material. 1H NMR spectra confirmed the incorporation of 3‐PDCA onto PAA and a series of HMPs with three different molar concentrations, viz ? 3, 5 and 7 mol‐% of 3‐PDCA, were synthesized. An increase in viscosity with increasing hydrophobic content was observed by rheological measurements. The critical association concentrations were determined using an Ubbelohde viscometer and a controlled stress rheometer. The stability of HMPs towards temperature and shear was studied. Rheological measurements showed that there was a steady increase in viscosity with increase in hydrophobe content due to the formation of reversible networks. These polymers exhibited gel‐like behavior at low concentrations (≥2 wt.‐%) with an apparent yield stress (ca. 10 Pa) and showed shear thinning properties (non‐Newtonian). However, below a critical concentration, c [η], they showed Newtonian behavior.

ηsp of unmodified and modified PAA‐Na at various polymer concentrations.  相似文献   

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Lasers in Medical Science - Transurethral endoscopic incision is an established treatment option for management of obstructing ureterocele. It can be performed using monopolar electrocautery or...  相似文献   
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Most metatarsal neck fractures can be successfully treated non-operatively in a cast boot. Displaced metatarsal neck fractures tend to be less stable and have a propensity for the distal fragment to angulate, secondary to the strong flexor tendons, which often forces the distal fracture fragment in a plantar direction and leads to relative metatarsal shortening. Most literature is focussed on antegrade fixation of metatarsal neck fractures using pre-bent K wires or thin elastic nails. Apart from the technical challenges, this technique is limited when bones are osteoporotic as the pre-bent distal end of the K-wire may penetrate the plantar cortex of the proximal metatarsal and prevent the wire from entering the medullary canal of the metatarsal and advancing to the fracture site. Furthermore, when the medullary canal is narrow especially in Asian patients, it may be difficult to pass a bent K-wire through the isthmus of the metatarsal shaft. We describe an innovative technique of closed transverse wiring of the metatarsal head necks that has a distinct advantage in Asian population with osteoporotic bones. With percutaneous manipulation using digital pressure, closed reduction of fracture fragments of the most displaced fracture is done under fluoroscopic guidance to achieve a satisfactory alignment followed by closed transverse wiring of the metatarsal heads. With this procedure, adjacent fractures remain stable within an acceptable range because of intermetatarsal ligaments connected to the adjacent intact head. Our technique has a relatively short operating time and allows for early motion of the metatarso-phalangeal joint. This is especially useful for those with osteoporosis, narrow canal, soft tissue compromise, intra-operative failure of ante-grade pinning and in scenarios of limited surgical equipment/expertise.  相似文献   
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