Dipyridamole alone or combined with low-dose acetylsalicylic acid inhibits platelet aggregation in human whole blood ex vivo.

1. In a randomized, double-blind trial we compared the inhibition of the platelet-vessel wall interactions in whole blood ex vivo. There were four groups of 24 healthy volunteers each of whom were treated orally for 3.5 days with either 200 mg dipyridamole (sustained release preparation), 25 mg acetylsalicylic acid, both drugs combined or placebo twice daily. 2. The mean area of all platelets/aggregates was reduced by 6.2% +/- 4.2% (+/- s.e. mean) by placebo (n = 23), 19.8% +/- 6.7% by dipyridamole (n = 22), 53.7% +/- 4.9% by acetylsalicylic acid (n = 23) and 71.4% +/- 3.7% by the combination of both drugs (n = 24), when compared with total inhibition of aggregation by EGTA. Thus, low-dose acetylsalicylic acid inhibited aggregation (P less than 0.001). 3. Dipyridamole reduced the size of platelet aggregates (P less than 0.01, two-fold analysis of variance). The reduction was correlated with the individual dipyridamole plasma levels (P less than 0.05, analysis of covariance). The subgroup of large and very large thrombi being formed was also reduced by dipyridamole (P less than 0.05). 4. This ex vivo study demonstrates that dipyridamole alone inhibits formation of thrombi on subendothelial matrix and enhances the inhibitory effect of low dose acetylsalicylic acid in this model of thrombosis.     

6β-乙酰氧基去甲托烷呼吸抑制效应

6β-乙酰氧基去甲托烷(6β-acetoxynortropane,6β-AN)是一种新型M2受体激动剂,兔10ug·kg^-1iv,犬2,5,20ug·kg^-1iv均导致呼吸频率、潮气量、每分通气量明显减少(P<0.05或0.01),呈剂量依赖关系。pO₂降低,pCO₂升高。较小剂量给兔0.5,1.0,2.0,4.0ug·kg^-1iva和犬0.25,0.5,1.0ug·kg^-1iva亦产生与静脉给药相似的呼吸抑制效应。AF-DX116能拮抗6β-AN的呼吸抑制作用,PZ则与6β-AN产生协同作用。表明6β-AN有呼吸抑制作用,并可能与其激动呼吸中枢M2受体有关。     

Ethmoid sinus disease: CT evaluation in 400 cases. Part II. Postoperative findings

Clinical, pathologic, and computed tomographic (CT) findings were reviewed in 400 patients with ethmoid sinus disease, including 272 who had undergone surgery. The postoperative appearance of ethmoid sinuses on CT scans is a highly neglected subject in radiologic literature. The unique ethmoid anatomy permits a variety of surgical approaches, and radiologists must be familiar with the postoperative appearances if they are to recognize the effects of prior surgery and detect, when possible, the recurrence of disease. It is often difficult to evaluate the clinical significance of soft-tissue disease, despite good clinical correlation.     

Aneurysmal bone cysts: MR imaging at 1.5 T

Two patients with aneurysmal bone cysts of the pelvis were imaged using a 1.5-T magnetic resonance imaging device. Findings included multiple internal septations, cysts with fluid-fluid levels of varying intensity, and an intact rim of low-intensity signal completely surrounding the lesion. These findings allow a specific diagnosis of aneurysmal bone cyst to be made.     

Use of microdilution to assess in vitro antiamoebic activities of Brucea javanica fruits, Simarouba amara stem, and a number of quassinoids.

A microdilution technique for the assessment of in vitro activity against Entamoeba histolytica was devised and validated with metronidazole. The test was used to detect the antiamoebic activities of plant extracts prepared from the traditional remedies Brucea javanica fruits and Simarouba amara stems. The activity was associated with quassinoid-containing fractions. The 50% inhibitory concentrations for some quassinoids against amoebae were determined by using the microdilution method. These concentrations ranged from 0.019 micrograms.ml-1 for bruceantin, the most active quassinoid, to greater than 5 micrograms.ml-1 for glaucarubol, the least active compound tested. These results are discussed with reference to the known activities of these compounds against Plasmodium falciparum. Overall, the activities of the quassinoids against both protozoa are similar. The microdilution technique will be useful in the search for novel antiamoebic drugs.