Drug release from reservoir pellets compacted with some excipients of different physical properties

The aim of the present study was to investigate the influence of the size and the porosity of excipient microcrystalline cellulose (MCC) particles on the densification and the deformation during compaction and the consequent effect on the drug release from reservoir pellets. Drug pellets consisting of salicylic acid and microcrystalline cellulose were prepared by extrusion-spheronisation and spray-coated with ethyl cellulose (ethanol solution). Excipient pellets of different size and porosity were prepared by extrusion-spheronisation or direct spheronisation. Five binary mixtures of reservoir pellets and excipient particles were prepared in the proportion 1:7 and lubricated. After compaction the reservoir pellets were retrieved and analysed to determine the intragranular porosity, surface area, shape and drug release. The reservoir pellets were shown to undergo extensive deformation and densification during compaction, resulting in a preserved or even prolonged drug release time. The mode of deformation of the reservoir pellets seems to be critical for the compression-induced change in drug release. Formation of large indents has a negative effect on the release time, while the use of small particles or small deformable agglomerates has a protective effect. We also hypothesize that the coating structure changes during compaction and the final structure of the coating is the net effect of two parallel processes, one reducing and one prolonging the drug transport time across the coating.     

Imaging of compressive vertebral haemangiomas

Compressive vertebral haemangiomas (VHs) are rare. Correct preoperative diagnosis is useful both for operative planning (since compressive VHs are extremely vascular lesions) and to allow preoperative embolisation. Numerous radiological signs for VHs have been described, but compressive VHs frequently have atypical features. In particular, magnetic resonance features are not well established. We present imaging features in three cases of compressive VH and review the imaging findings in an additional 106 previously published cases. Findings were typical in 52 of 80 plain film (65 %), 33 of 41 computed tomography (80 %) and 13 of 25 magnetic resonance examinations (52 %). The prevalence of previously described imaging features is reported. Awareness of the range of magnetic resonance features is important since this is frequently the initial investigation in patients presenting with symptoms of neural compression. Since computed tomography is typical in 80 % of cases, this is a useful confirmatory test if magnetic resonance features are suspicious but not diagnostic of compressive VH. Received: 6 August 1999; Revised: 4 November 1999; Accepted: 4 November 1999     

血凝酶不同给药方法用于脊柱手术止血的效果

目的 :观察血凝酶在脊柱外科手术中局部和静脉 2种给药方法的止血效果。方法 :椎管减压、腰椎间盘摘除术病人 90例 ,随机分为 3组 ,每组 30例 ,3组病人手术指征及麻醉方法选择相同。合用组术前 15min血凝酶 1单位静脉注射 (静注 )、术中2单位稀释后在出血部位局部喷洒 ;静脉组术前 15min血凝酶 1单位静注 ,术中 2单位静脉滴注 ;对照组不应用任何止血药物。观察 3组病人术中出血量、浓缩红细胞输入量和生命体征。结果 :同对照组比较 ,合用组和静脉组术中出血量、浓缩红细胞输入量均明显减少 (P <0 .0 1) ,合用组又少于静脉组 ,(6 89±s 15 0 )mLvs (80 3± 186 )mL ,P <0 .0 5 ,(2 .3± 0 .3)Uvs(2 .7± 0 .5 )U ,P <0 .0 1。 3组病人术中 2h血压、心率、呼吸和动脉血氧饱和度比较 ,无显著差异 (P >0 .0 5 )。结论 :血凝酶在脊柱外科中可明显减少手术过程中的出血量 ,同时减少浓缩红细胞输入量 ,局部喷洒同静脉共同应用效果更加显著。     

Transient oculomotor nerve palsy due to non-aneurysmal neurovascular compression

Acute oculomotor nerve palsy requires urgent exclusion of aneurysmal compression. We report a 62 year old man with a transient right third nerve palsy with pupillary involvement, who was found to have neurovascular compression of the cisternal oculomotor nerve as it curved over a duplicated superior cerebellar artery on high resolution MR imaging. Direct vascular compression should be considered in patients with isolated cranial neuropathies in whom other pathologies have been excluded.     

Safety and Usability of Hemostats,Sealants, and Adhesives

Hemostats, sealants, and adhesives are an integral part of surgical patient care. Nurses who have knowledge about these agents can better help ensure safe, efficient surgical patient care. As a caregiver and patient advocate, the perioperative nurse must understand the most current information about these agents and be prepared to facilitate the transfer of this knowledge to all caregivers. Information about these agents, including the contraindications, warnings, and precautions associated with their use as well as their preparation and application, is provided here. Algorithms designed to clarify the best options for using hemostats, sealants, and adhesives are included as well.     

重症肝炎患者静脉采血后按压方法效果的比较与分析

目的对单棉签平行血管按压法和双棉签并排垂直血管按压法的效果进行比较,选择更好的按压方式尽可能地减少重症肝炎患者在静脉采血后可能出现的皮肤出血、血肿、皮下瘀斑等不良情况,减轻病患的痛苦。方法将重症肝炎患者与普通患者分为观察组与对照组,在组内又分别采用单棉签平行血管按压法和双棉签并排垂直血管按压法进行止血,并记录各组的反应情况。结果观察组内采用双棉签并排垂直血管按压法,皮肤出血、血肿、皮下瘀斑的概率明显低于采用单棉签平行血管按压法(P<0.01),差异具有统计意义;而对照组内采用两种按压方式出现不良反应的概率差异无统计学意义。结论对普通患者而言,两种按压方式的差别不大;但对于重症肝炎患者来说,双棉签并排垂直血管按压法能够有效地降低皮肤出血、血肿和皮下淤斑的发生率,进而达到更好的治疗和护理效果。