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111.
Epistaxis     
《Surgery (Oxford)》2021,39(9):577-590
Epistaxis is a common problem that can affect the whole population. The majority of cases are self-limiting and do not require any medical intervention, but epistaxis can be associated with morbidity and even death in very rare circumstances. If epistaxis does not resolve with first aid measures, or episodes are frequent, patients may require specialist assessment and treatment by ENT, either in the outpatient clinic or via an unscheduled (emergency) admission to the hospital. Here, we provide an overview of the management of epistaxis in the outpatient setting and during an emergency admission in both paediatric and adult patients. We highlight the key considerations in the history and management, covering the common and rare conditions that are associated with epistaxis. This article provides an update from our previous article published in 2018 to include the more recent literature and a useful learning resource for examinations.  相似文献   
112.
C. Lyons  M. Callaghan 《Anaesthesia》2021,76(1):118-127
Apnoeic oxygenation refers to oxygenation in the absence of any patient or ventilator effort to move the lungs. This phenomenon was first described in humans in the mid-20th century but has seen renewed interest in the last decade following the demonstration of apnoeic oxygenation with low-flow, and subsequently high-flow, nasal oxygen. This narrative review summarises our understanding of apnoeic oxygenation in the paediatric population. We examine the evidence supporting oxygenation via tracheal tube, modified laryngoscopes and nasal cannulae. The evidence for prolongation of safe apnoea time at induction of anaesthesia is also appraised. We explore the capacity for carbon dioxide clearance, flow rate selection with high-flow nasal oxygen and complications associated with the technique. It remains uncertain whether apnoeic oxygenation in paediatric patients results in a meaningful clinical benefit compared with standard care for outcomes such as the number of tracheal intubation attempts or the incidence of hypoxaemia. In particular, the role of apnoeic oxygenation in paediatric difficult airway management is unclear as this has not been the targeted focus of any published research to date.  相似文献   
113.
目的 优选经典名方华盖散基准样品的干燥方法。方法 采用真空干燥、真空带式干燥、喷雾干燥、冷冻干燥方法制备华盖散基准样品,应用扫描电子显微镜、差式扫描量热分析、HPLC等方法测定基准样品的质量属性,以得粉率、玻璃化转变温度及成分含量转移率等为评价指标,运用熵权法对各指标赋予权重进行综合评价。结果 喷雾干燥基准样品粒子呈类球形、粒径最小,冷冻干燥基准样品不规则、蓬松、溶化性好。指标成分盐酸麻黄总碱、苦杏仁苷、橙皮苷、甘草苷、甘草酸转移率分别为85.66%~104.78%、90.81%~104.16%、91.42%~94.86%、83.98%~94.69%、87.85%~94.45%,指纹图谱相似度均大于0.9。结论 经综合评价得出冷冻干燥方法最佳,3批验证工艺重复性、可行性较好,为经典名方基准样品质量属性研究提供了理论依据和实践价值。  相似文献   
114.
罗毓  李金枝  阮洪生  吴玲玲  林晓 《中草药》2023,54(10):3141-3149
目的 以干姜Zingiberis Rhizoma醇提物为研究对象,研究表面改性、聚集与致孔相结合的共处理方式改善干姜醇提物的压片关键性能。方法 以共聚维酮(plasdone S-630,PVP/VA)和碳酸氢铵分别为改性剂和致孔剂,采用喷雾干燥共处理方法制备不同比例的干姜醇提物改性复合粉体,测定并比较各粉体的密度、流动性、粒径、孔隙率和压缩性等粉体学性质和抗张强度、屈服压、功和能等相关压片性质,并采用扫描电子显微镜(SEM)对各粒子表面形态进行表征。结果 仅加入共聚维酮或碳酸氢铵制备的复合粒子的孔隙率、抗张强度(TS)、有效功(Esp)和能(E2)均优于原粉粒子。此外,相比于碳酸氢铵或共聚维酮单独制备的复合粒子,碳酸氢铵-共聚维酮(7.0%、14.0%、21.0%)共喷雾制备的复合粒子所压制片剂的抗张强度进一步提升:分别为(1)3.8~9.7、4.0~12.5、4.2~13.7倍和(2)1.5~2.1、1.3~2.2、1.2~1.8倍。即同时加入共聚维酮和碳酸氢铵制备的多孔复合粒子使上述性质得到进一步改善。另外,崩解时间会随共聚维酮加入而有所延长(9~14 min),碳酸氢铵的致孔作用...  相似文献   
115.
鼻成形术中额颞部血管的应用解剖学研究   总被引:32,自引:4,他引:32  
目的:为解决临床上额部皮瓣修复鼻缺损时常出现的血运障碍,全鼻再造时的衬里缺损以及应用耳廓复合组织修复鼻翼缺损时面积受限等问题。方法:对29例(58例)尸体额、鼻和颞部血管进行解剖。结果:滑车上动脉由两侧向内上行走,滑车上动脉的分支、眶上动脉的浅支、颞浅动脉额支的额眶支相互吻合成网前额动脉吻合网。颞浅动脉主干及顶支发出2~3支耳支分布至耳轮。结论:额部皮瓣应设计在旁正中的滑车上动脉血管走行轴线上;可同时用两侧额部皮瓣行全鼻缺损的修复;亦可经前额动脉吻合网、颞浅动脉及其分支,设计出带蒂的大面积耳廓复合组织岛状瓣修复大面积鼻翼缺损或半鼻缺损  相似文献   
116.
A rat model has been developed to compare relative morphological changes in the nasal mucosa after exposure to potential membrane permeation enhancers. Scanning electron microscopy was used to characterize gross structural and specific cellular changes following exposure. Micrographs of the rat nasal mucosa were scored in four categories: (1) mucosal surface integrity, (2) ciliary morphology, (3) mucus/extracellular debris, and (4) presence of red blood cells. The order of increasing morphological damage resulting from a 5-min exposure to each surfactant was 0.5% Solulan C-24 0.5% Solulan C-24/0.5% sodium tauro-24,25-dihydrofusidate (STDHF) < 0.5% STDHF < 1.0% STDHF 1.0% Laureth-9 < 1.0% sodium taurodeoxycholate 1.0% sodium deoxycholate. The changes observed in the mucosal morphology after exposure to the various surfactants are in general agreement with data in the literature. This model is able to compare rapidly the relative morphological effects on the mucosal membrane of different nasal formulations.  相似文献   
117.
Bile salts and synthetic surfactants have been used to promote nasal absorption of peptide drugs. Although a marked increase in nasal absorption has been achieved, this may not be adequate and the possibility of adjuvant-induced membrane toxicity exists. The present study employs a rat in situ nasal perfusion technique and mixed micelles between sodium glycocholate (NaGC) and various lipids as potential nasal absorption enhancers of a stable model dipeptide, [D-Arg2]kyotorphin. NaGC alone enhanced the nasal absorption of the dipeptide in a concentration-dependent manner. When linoleic acid was added to form mixed micelles with NaGC, the absorption was further enhanced (P < 0.01). The effect of mixed micelles was synergistic and much greater than with single adjuvants. Increasing ionic strength was found to increase the adjuvant activity of both NaGC and NaGC–lipid mixed micelles. Structure of the lipid component of the mixed micelles also affected the adjuvant potency. Oleic acid, a cis-unsaturated fatty acid, was more effective than elaidic acid, the trans-isomer, whereas cis-linoleic acid and trans-linolelaidic acid were equally effective ( = 0.05). Mixed micelles of mono-glycerides such as monoolein and monolinolein were also more effective than NaGC alone ( = 0.05). Micellar solubilization of these polar lipids by NaGC appears to be important for nasal absorption enhancement to occur. Reversal of the membrane permeability was also observed within approximately 20–40 min after removal of the adjuvants from the rat nasal cavity. These observations are similar to the effects of mixed micelles on the rectal mucosa and may involve the same mechanism.  相似文献   
118.
报道应用 L C- MS/ MS,采用音喷离子化 (SSI)与大气压化学离子化 (APCI)对利血平的比较分析 ,应用这两种离子化方法比较所得的利血平的标准质谱 (MS)和二级质谱 (MS2 ) ,实验证明两种离子化方法所得结果完全一致  相似文献   
119.
高效液相色谱柱后衍生法测定豚鼠鼻粘膜中组胺   总被引:1,自引:0,他引:1  
通过比较各种分析柱的分离效果 ,建立用离子交换柱分离 ,邻苯二甲醛 (OPA)柱后衍生荧光检测并分析豚鼠鼻粘膜组织中组胺的液相色谱方法 ,并对流动相的离子强度和pH进行了优化 ,确定以 40mmol·L- 1 pH 5 .5 0的柠檬酸钠缓冲液作为流动相为最佳条件。该方法的最低检测限为 5 0nmol·L- 1 ,回收率 >92 % ,线性范围为 5 0nmol·L- 1~ 5 0 0 μmol·L- 1 ,组胺的保留时间为 13min 12s,组胺峰面积的相对标准差 <3%。  相似文献   
120.
目的 分析影响鼻窦显微手术疗效的因素。方法 鼻内筛窦手术,经上颌窦手术,上颌窦窦口扩大,中鼻道开窗。结果 359侧鼻窦显微手术,术后1~4年(平均36.4个月),随访288侧,治愈108例(37.5%),显著进步87例(30.2%),好转65侧(22.6%),无效28侧(9.7%),良好率67.7%,鼻内筛窦手术良好率60.6%,经上颌窦手术良好率72%,上颌窦窦口扩大未闭良好率60.1%,中鼻开  相似文献   
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