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1.
顺铂聚乳酸微球的药物释放特性及肝动脉栓塞研究   总被引:5,自引:0,他引:5  
对顺铂聚乳酸微球进行了体外药物释放和家犬肝动脉栓塞研究。该微球粒径范围为50~200μm,平均粒径为115.76±35.94μm,顺铂含量为37.16%(W/W);体外药物释放机制符合Higuchi方程;肝动脉栓塞后8h,肝组织顺铂浓度高达21.55±12.18μg/g,明显高于肝动脉灌注顺铂组:3.16±0.09μg/g(P<0.05);肝动脉栓塞组的顺铂血浓峰值、各取血点浓度及曲线下面积AUC皆低于肝动脉灌注顺铂组。可望达到提高栓塞部位的药物疗效,降低全身毒副反应的作用。  相似文献   
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Primary tuberculous pathology in nasolpolypi is a rare condition. A case of bilateral ethmoidal polypi with tubercular lesion diagnosed on histopathologlcal examination is being reported and the available relevant literature has been reviewed.  相似文献   
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BACKGROUND: Many patients with asthma or chronic obstructive pulmonary diseaseuse their medication inhalers incorrectly. General practitioners,pharmacists and other health care providers do not always havethe opportunity to instruct patients in correct inhaler technique. OBJECTIVE: To find out whether the inhaler technique and respiratory symptomsof patients can be improved after instruction by practice assistants. METHODS: Single blind, randomized intervention study in which 48 patientswho had been using a dry powder inhaler for at least one monthtook part. Their inhaler technique was videotaped on two visitswith a two-week interval between visits. The inhaler techniqueon the videos was subsequently scored by two experts on ninecriteria. At both visits the patients completed a questionnaireabout their respiratory symptoms. After the first video, 25patients were randomly chosen to receive instruction from oneof six practice assistants who had followed a one evening courseabout inhaler instruction, and who had been issued an instruction-set. RESULTS: The patients who received instruction had a significantly greaterreduction in number of mistakes at the second visit than thepatients who did not (P = 0.01). The instructed patients alsoreported less dyspnoea at the second visit (P = 0.03). No effectof instruction was found on wheezing, cough and sputum production. CONCLUSION: The inhaler technique of patients can be improved significantlyby the instruction of patients by trained practice assistants,possibly resulting in less dyspnoea. Keywords. Administration-inhalation, obstructive lung diseases, airways symptoms, patient-education, general practice.  相似文献   
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In situ saphenous vein grafts are being used with increasing frequency for bypass procedures involving the femoral and popliteal arteries. Complications of these procedures include anastomotic stenoses and persistent arteriovenous fistulae that may result in failure of the graft. Balloon angioplasty and embolotherapy with detachable balloons were employed successfully in three or four recent cases of patients with complications from in situ grafts. Tailored angiography is essential for evaluating in situ grafts, and interventional techniques are extremely useful for managing complications.  相似文献   
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Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy.  相似文献   
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背景:以往对面部肉芽肿(GF)的研究仅局限于病例报道或小样本研究。目标:通过对GF的大样本研究,描述其临床病理特征。方法:对66例患者和73份皮肤组织标本进行回顾性分析。结果:GF通常发生在中年人,表现为淡红色斑块或结节,1/3患者有多个皮损,5例患者有面部以外皮损。只有10例患者临床诊断为GF;其主要鉴别诊断包括:肉样瘤病、淋巴瘤、狼疮及基底细胞癌。GF最常见的组织病理学特征为一条grenz带、中性粒细胞浸润及毛细血管扩张。尽管坏死性血管炎罕见,但血管改变常见。通常皮损同时存在急性和慢性炎症,提示GF为急性复发的慢性过程,而不是一个明显连续的急性和慢性阶段。  相似文献   
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The occurrence of hyperplastic pacinian corpuscles in the hand is rare, with only 13 cases reported in the literature. We describe such a case in a 70-year-old male who had worked as a locksmith for many years. A grape-like cluster of firm, rice-sized nodules was discovered in the subcutaneous tissue of the finger following a glass-induced injury. Histopathological findings revealed pacinian corpuscles to be increased in size and number. Individual corpuscles consisted of a central nerve fiber surrounded by 35 to 60 concentric lamellae (normal controls from other specimens: 13–15 lamellae). The external corpuscular diameter ranged from 1.8 to 3.2 mm (normal controls from other specimens: 1.6 mm). Immunohistochemistry showed positive staining with Leu 7 antibody and anti-glial fibrillary acidic protein in the small nerves situated in the vicinity of the pacinian corpuscles, but not in the corpuscles themselves. The lesion reported here clearly differed from both neurofibroma with occasional pacinian differentiation and the so-called pacinian neurofibroma. There was no evidence of neurofibromatosis.  相似文献   
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