顺铂聚乳酸微球的药物释放特性及肝动脉栓塞研究

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。     

Primary tuberculous nasal polypi—A case report

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.     

Minimizing macrovessel signal in cerebral perfusion imaging using independent component analysis.

The pronounced susceptibility effect of macrovessels in MR bolus-tracking studies induces spots of artificially high blood flow and volume in perfusion parameter images. These high-intensity regions impede the detection of perfusion changes and lead to elevated perfusion parameters in adjacent tissues. The purpose of this work was to explore postprocessing methods to reduce the influence of macrovessel signal in dynamic MRI. After data reduction was performed with the use of a principal component analysis (PCA), an independent component analysis (ICA) was applied to separate signal components of different compartments. Based on this decomposition, the dynamic time series were reconstructed with minimized contributions of macrovessel signal and noise. The influence of the temporal resolution and signal-to-noise ratio (SNR) of the source data were investigated by means of a simulation study. A region-of-interest (ROI)-based analysis of corrected and uncorrected in vivo data demonstrated that the influence of arteries and veins was reduced at least by 50%, while gray matter (GM) and white matter (WM) tissues were nearly unaffected by the correction process. Hemodynamic parameter images of the cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time (MTT) were calculated from corrected and uncorrected scans. The corrected parameter images showed a clearly reduced macrovessel signal and an improved perceptibility of microvascular perfusion changes compared to the uncorrected ones.     

Effects of instruction by practice assistants on inhaler technique and respiratory symptoms of patients. A controlled randomized videotaped intervention study

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.     

Initial experience with Tc-99m-HM-PAO in the study of brain tumors

A preliminary study of the distribution of the 99mTc complex of hexamethylpropylene amine oxime (HM-PAO) in 12 patients with brain neoplasms before, during, and after radiotherapy has been performed. Untreated brain tumors were found to exhibit a range of 99mTc-HM-PAO uptake, varying from areas of markedly increased isotope activity to photopenic areas, when compared to normal brain tissue. A ratio of 99mTc-HM-PAO tumor uptake to contralateral normal tissue uptake was calculated prior to and during radiotherapy. This ratio tended to return towards unity in lesions responding to therapy. A predictable alteration in whole brain 99mTc-HM-PAO uptake during radiotherapy was not demonstrated. Unlike the radiolabeled amines, 99mTc-HM-PAO localizes in primary tumors, probably indicating that its uptake mechanism is independent of non specific amine receptors. 99mTc-HM-PAO may be useful in the study of brain tumor physiology and response to therapy.     

Parathyroid imaging. Use of dual isotope scintigraphy for the localization of adenomas before surgery.

Seventy-nine patients with primary hyperparathyroidism, whose average preoperative blood calcium level was 11.6 mg/dl, underwent thallium-technetium dual isotope scintigraphy of the thyroid and parathyroids. For patients who had surgery, the detection and localization rate of parathyroid disease or the sensitivity was low (0.53), but the positive predictive value for the location was high (0.80). Correct localization correlated positively with the weight of the tumor but not significantly with the parathyroid hormone blood level nor with the blood calcium level. Unprocessed data alone were sufficient to predict correctly the location in two thirds of the detected cases. Computer processing increased the sensitivity without decreasing the specificity. Those results, at variance with earlier published data but congruent with another more recent study, require a reevaluation of the role of this scintigraphic technique in the management of hyperparathyroidal patients.     

Frequency of adverse reactions to radiopharmaceuticals in Europe

A prospective survey was performed in 17 nuclear medicine departments during 1996 in an attempt to provide reliable data on the prevalence of adverse reactions to radiopharmaceuticals. All adverse events following radiopharmaceutical administration were recorded, irrespective of the severity or likelihood of causality, and subsequently analysed using an algorithm developed by Silberstein et al., designed to establish a cause-effect relationship. A prevalence of 11 events per 105 administrations was obtained (95% confidence limits 3.3–19.2). No serious of life-threatening events were reported. This rate is slightly higher than that obtained in a larger scale study in the United States (2.3 events per 105 administrations, 95% confidence limits 1.2–3.4). The difference may be due to the decision to include or exclude vasovagal events from the analysis, the way in which the algorithm was used and the comparative size and time scale of the two studies. The prevalence of adverse reactions is approximately 1000-fold than less that occurring with iodinated contrast media and drugs.     

Phaeohyphomycotic cutaneous disease caused by Pleurophoma in a cardiac transplant patient

A 56-y-old female cardiac transplant patient treated with cyclosporine and prednisone noted the onset of three nontender red nodules on the legs and arms after gardening. Biopsy of all lesions revealed inflammatory cells and hyphal elements in the dermis. The dematiaceous fungus cultured from biopsy tissue was a pycnidial-forming organism of the genus Pleurophoma. The lesions responded to the topical application of miconazole.     

In situ saphenous vein bypass grafts: angiographic evaluation and interventional repair of complications

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.