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21.
本文介绍一种用流态化技术与喷雾干燥相结合的方法将苯甲酸钠溶液在流化床内完成蒸发、干燥与造粒。  相似文献   
22.
Effect of buffering on pharmacokinetics of ketoprofen enantiomers in man   总被引:1,自引:0,他引:1  
Aims Concomitant administration of magnesium hydroxide may affect the rate or extent of absorption of non-steroidal anti-inflammatory drugs. In order to find out whether or not buffering modifies the pharmacokinetics of ketoprofen, plasma concentration-time courses resulting from oral administration of unbuffered formulations were compared with those of buffered formulations.
Methods Two groups of 12 healthy and young male subjects were included in two randomized cross-over studies and received single oral doses of ketoprofen 12.5 or 25  mg, respectively, given as tablets which were either unbuffered or buffered with magnesium hydroxide/citrate. Ketoprofen enantiomers in plasma were determined by h.p.l.c. up to 24  h post-dose.
Results Maximum plasma concentrations ( C max ) of both the (R)- and (S)-enantiomer, observed after administration of the buffered formulations (12.5 and 25  mg), were higher compared with the unbuffered tablets by about 50–80%. The area under concentration-time data (AUC) was unaffected, and, hence, C max/AUC was increased by buffering. Time to C max ( t max ) and mean residence time (MRT) tended to be or was shortened by buffering.
Conclusions It is concluded that buffering of two ketoprofen formulations with magnesium hydroxide/citrate enhanced the concentration maximum by increasing the rate of absorption and leaving AUC unaffected.  相似文献   
23.
GE 68 ((Rac.)-1-[3-(Phenylethyl)-2-benzofuryl]-2-(propylamino)-ethanol hydrochloride) is structurally related to propafenone, and exerts negative inotropic and negative chronotropic effects similar to the parent drug, but lacks any β-adrenoceptor blocking activity contrary to propafenone. Thus, the electrophysiological effects of GE 68 were studied in papillary muscles, left atria, Purkinje fibres, sinoatrial nodes and ventricular myocytes of the guinea-pig heart with the intracellular microelectrode technique and the patch-clamp technique in the cell-attached mode. The decrease of the maximum upstroke velocity (V˙max) by GE 68 (1 to 10 μM) was use- and frequency-dependent. V˙max recovered from the use-dependent block with a time constant of 4.1 ± 0.6 s. In papillary muscles and Purkinje fibres action potential duration was shortened, while it was prolonged in left atria and sinoatrial nodes. Half-maximal steady-state inactivation of the sodium channels was shifted to more negative membrane potentials (control: –91.5 ± 0.8 mV, 10 μM GE 68: –97.9 ± 2.5 mV). The peak of the current-voltage relationship and the reversal potential were not changed by GE 68. The amplitude of the unitary current remained unaltered, while open state probability was decreased. The most striking effect of GE 68 was an increase of the number of sweeps without single channel openings (1 μM: 2 fold, 10 μM: 6 fold). GE 68 also caused a decrease of the mean open times, and an increase of the mean closed times in unmodified and pronase-modified sodium channels. Besides the lack of β-adrenoceptor blocking activity, data present a faster recovery from the use-dependent block by GE 68 and a lower affinity to inactivated sodium channels compared to the reference drug propafenone, as well as differences in the effect on single channel kinetics. Received: 25 July 1996 / Accepted: 14 October 1996  相似文献   
24.
用二巯基丙磺酸钠对苯硫丹、多噻烷急性染毒小鼠进行保护解救。结果表明:二巯基丙磺酸钠对该两农药急性染毒小鼠具有显著的保护作用(P<0.05)。本实验填补了以二巯基丙磺酸钠作为首选药物治疗沙蚕毒系现有全部品种急性中毒解毒谱的空白。  相似文献   
25.
目的:观察高渗氯化钠高氧液对失血性休克家兔动脉血气和血乳酸值的影响,评价其对失血性休克的早期救治效果。方法:制备高渗氯化钠溶液(HS)、生理盐水高氧液(NSO)和高渗氯化钠高氧液(HSO)。30只雄性家兔制备失血性休克模型[于10min内使平均动脉压(MAP)降至40mmHg(1mmHg=0.133kPa),维持60min],随机分为NSO,HS,HSO组3个治疗组。分别按6mL/kg剂量5min内静脉输入NSO,HS和HSO。记录休克前后及给药后心率(HR)、呼吸(RR)、MAP及尿滴(UD),测定休克前、休克60min,给药后30,60,120min时血乳酸(BL)和动脉血气值。最后观察尸肺,测定肺系数。结果:HS和HSO组均显著地改善MAP,HR和UD,降低BL,改善代谢性酸中毒,肺系数明显低于NSO组。HSO与NSO及HS比较,能更显著地降低血BL,提高动脉血氧饱和度(SaO2)和动脉血氧分压(PaO2)。结论:HSO较HS和NSO能更显著地降低血BL,提高SaO2和PaO2,对失血性休克的早期救治具有较高的使用价值。  相似文献   
26.
作者选择乙基纤维素、聚乙烯醇等高分子材料制成涂膜剂,用大鼠皮进行双氯灭痛药膜的体外透皮速率测定。结果表明,氮酮与丙二醇可以促进药物渗透。不同的高分子材料可影响药物的扩散与释放,从而影响其透皮速率。与无膜无促透剂处方相比,药物在乙基纤维素中的透皮速率没有增加,在聚乙烯醇膜中的透皮速率有显著增加。  相似文献   
27.
目的 评价溴敌隆防制家栖鼠的效果。方法 实验室有选择适口性试验 ,现场灭家栖鼠效果考核。结果 在有选择的摄食试验条件下 ,0 .0 0 5 %溴敌隆大米毒饵对褐家鼠和黄胸鼠的毒杀率达 10 0 %和 94 .4 4 % ,摄食系数分别为 0 .6 3和 0 .5 4 ,致死剂量分别为 9.97(0 .0 6~ 2 4 .6 9)和 7.93(5~ 17.6 1)mg/kg。现场灭家栖鼠试验 ,灭鼠率达 86 .4 3%。结论 溴敌隆对家栖鼠毒效髙 ,适口性好 ,具有较好的防制效果  相似文献   
28.
本文建立了用于甘氨酸茶碱钠中茶碱含量测定的紫外分光光度法。将样品溶于0.1mo1/L氢氧化钠溶液中,在274nm波长处测其吸收度,结果的相对标准偏差(RSD)为0.22%.与药典方法比较,F.t检验均无显著性差异.本法简便,快速,结果可靠,准确.  相似文献   
29.
β2-glycoprotein-I (β2GPI) is a phospholipid-binding plasma protein that consists of five homologous domains. Domain V is distinguished from others by bearing a positively charged lysine cluster and hydrophobic extra C-terminal loop. β2GPI has been known as a natural anticoagulant regulator. β2GPI exerts anticoagulant activity by inhibition of phospholipid-dependent coagulation reactions such as prothrombinase, tenase, and factor XII activation. It also binds factor XI and inhibits its activation. On the other hand, β2GPI inhibits anticoagulant activity of activated protein C. According to the data from knockout mice, β2GPI may contribute to thrombin generation in vivo. Phospholipid-bound β2GPI is one of the major target antigens for antiphospholipid antibodies present in patients with antiphospholipid syndrome (APS). Binding of pathogenic anti-β2GPI antibodies increases the affinity of β2GPI to the cell surface and disrupts the coagulation/fibrinolysis balance on the cell surface. These pathogenic antibodies activate endothelial cells via signal transduction events in the presence of β2GPI. Impaired fibrinolysis has been reported in patients with APS. Using a newly developed chromogenic assay, we demonstrated lower activity of intrinsic fibrinolysis in euglobulin fractions from APS patients. Addition of monoclonal anti-β2GPI antibodies with β2GPI also decreased fibrinolytic activity in this assay system. β2GPI is proteolytically cleaved by plasmin in domain V (nicked β2GPI) and becomes unable to bind to phospholipids, reducing antigenicity against antiphospholipid antibodies. This cleavage occurs in patients with increased fibrinolysis turnover. Nicked β2GPI binds to plasminogen and suppresses plasmin generation in the presence of fibrin, plasminogen, and tissue plasminogen activator (tPA). Thus, nicked β2GPI plays a role in the extrinsic fibrinolysis via a negative feedback pathway loop.  相似文献   
30.
目的:对中国药典收载的头孢噻肟钠聚合物测定条件进行改进。 方法 :采用高效液相色谱法 ,以Sephadex G- 10色谱柱 4 2 cm× 1.3cm对 6批样品进行分析 ,分别进样 5 0μl和 2 0 0μl,按外标法计算聚合物的量。结果:头孢噻肟钠在 10~ 6 0 μg/m l范围内线性关系良好 (r=0 .9995 ) ,高中低浓度的加样回收率分别为 10 0 .2 %、10 0 .4 %、99.7% ;RSD分别为 1.7%、1.5 %、1.9% (n =3)。该方法与药典方法比较 ,差异无统计学意义 (P >0 .0 5 )。 结论:本方法简便、快速、可行 ,具有实用价值  相似文献   
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