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排序方式: 共有1188条查询结果,搜索用时 62 毫秒
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
2.
PC Chamyal A Mehta SL Ojha JR Bhardwaj 《Indian journal of otolaryngology and head and neck surgery》1991,43(1):26-27
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
3.
Impedance matching, optimum velocity, and ideal middle ears 总被引:1,自引:0,他引:1
One way to assess an ear's performance as a receiver of acoustic power is to consider impedance matching at the tympanic membrane. Assumptions about some of the impedances involved have lead to the idea of an optimum velocity magnitude (per unit pressure), which has been used as a test of middle-ear performance. We show that this approach is not a realistic way to assess effectiveness of power absorption at the tympanic membrane. More generally, we suggest that, if the performance of the combined external-and-middle ear in collecting acoustic power and delivering it to the inner ear is considered, the external- and middle-ear power-transfer efficiencies, as well as impedance matching, are involved in relating performance to an ideal. 相似文献
4.
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
5.
Paragangliomas are neuroendocrine tumours and those occurring in the head and neck have well recognized familial association. Retroperitoneal paragangliomas are uncommon and we present two cases of familial malignant retroperitoneal paraganglioma. Review of the literature revealed marked differences in the incidence and malignant potential of familial and non-familial paraganglioma. In contrast to the cases reported here, familial tumours are generally benign, though they may occur at multiple sites. Familial and non-familial paragangliomas may indeed be different disease entities. 相似文献
6.
Kinnison ML; Perler BA; Kaufman SL; Mitchell SE; Kadir S; Williams GM; White RI Jr 《Radiology》1986,160(3):727-730
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
7.
Digital radiography of subtle pulmonary abnormalities: an ROC study of the effect of pixel size on observer performance 总被引:3,自引:0,他引:3
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
8.
9.
Ruptured sinus of Valsalva aneurysms are rare. We report a case in which the usual clinical manifestations were not present and the patient was initially treated as an acute pulmonary embolus. Despite three negative echocardiograms an intra-cardiac shunt was suspected because of a persistently elevated mixed venous oxygen saturation. Cardiac catheterisation confirmed the diagnosis. Surgical repair was performed and post operative recovery was uneventful. 相似文献
10.
The aim of this study was to investigate insurance records for a one-year period to determine the injury frequencies and costs associated with different age groups in netball. The insurance records for all netball claims made during 1999 in Victoria were obtained from the insurer and entered into a database. The overall injury rate was 9.49 injuries per 1000 players, with 829 claims for injuries filed with the insurance company. Of all injuries claimed for, 85.3% were to the lower limb, 8.7% to the upper limb, 3.1% to the spine/torso and 2.9% to the head and face. Lower limb injuries accounted for 85.4% of costs, upper limb injuries 10.7% and head/neck/torso injuries 3.9% of total injury costs. Knee injuries accounted for 56.9% of total costs, with ankle and calf/Achilles injuries costing 12.7 and 11.8% of total costs, respectively. Injury prevention strategies should therefore be directed to three main injuries taking into account costs and incidence. These injuries were: ankle sprains, knee ligament sprains and Achilles tendon strains. Specifically, the prevention program for Achilles injuries should be directed to the >25 years age groups. 相似文献