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排序方式: 共有927条查询结果,搜索用时 15 毫秒
1.
目的探讨中药健肝愈胃汤(自拟)、西药心得安、奥美拉唑、胶态果胶铋胶囊联合治疗门脉高性胃病(PHG)的疗法。方法将136例PHG患者随机分成两组,对照组52例常规口服心得安、奥美拉唑、果胶铋;治疗组84例在常规服用以上西药的同时服用中药健肝愈胃汤。两组疗程均为2个月。结果治疗组临床治疗总有效率89.3%。显效率46.4%;对照组临床治疗总有效率80.7%,显效率13.5%。两组比较有显著性差异(P〈0.05)。结论中药健肝愈胃汤、西药心得安、奥美拉唑、果胶铋联合治疗PHG疗效显著。 相似文献
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Plasma concentrations and bioavailability of propranolol by oral, rectal, and intravenous administration in man 总被引:2,自引:0,他引:2
E Cid F Mella L Lucchini M Cárcamo J Monasterio 《Biopharmaceutics & drug disposition》1986,7(6):559-566
Eight normal male volunteers received 80 mg doses of propranolol by the oral and rectal routes and 2.2 mg by intravenous administration in a crossover fashion. Plasma concentrations of propranolol were measured by a gas chromatographic method using an electron capture detector. Individual subject concentration-time data were analysed and results indicated that the data fit a two compartment model with first order absorption. An approximately two-fold higher plasma propranolol concentration was observed after rectal administration as compared with oral dosing. Statistical analysis of the difference in the total AUCs indicates a significantly higher bioavailability of propranolol administered by the rectal route. The reduced bioavailability after oral administration indicates a substantial first pass effect but that it is possible to bypass the liver, at least partially, by giving the drug rectally to man. 相似文献
4.
目的:研究原料药粒径等对盐酸普萘洛尔渗透泵片释药行为的影响。方法:取不同批号盐酸普萘洛尔及同批号重结晶前、后的原料药均按相同处方制备成渗透泵片,考察药物体外释放情况及释药24h后衣膜形态;并对上述不同原料药的粒径分别以光学显微镜和激光粒度分析仪进行证实。结果:以原料药粒径较小的渗透泵片释放完毕后衣膜变形,且不能维持零级释放,原料药粒径较大的渗透泵片结果与之相反。不同原料药经仪器证实粒径确有差异。结论:原料药的粒径可影响制备的渗透泵片的释放行为,提示性状稳定的原料药的合理选择在制剂过程中不可忽视。 相似文献
5.
Autonomic nervous control of the heart rate response to dynamic incremental exercise: evaluation of the Rosenblueth-Simeone model 总被引:1,自引:0,他引:1
Jorge Pinto Ribeiro José Manuel Ibáñez Ricardo Stein 《European journal of applied physiology》1991,62(2):140-144
Summary To evaluate the validity of the Rosenblueth-Simeone model for the heart rate response to incremental dynamic exercise, 11 healthy men performed maximal exercise tests on a cycle ergometer after administration of placebo, propranolol, atropine or both propranolol and atropine. The model showed that the influence of sympathetic activity on heart rate increased at intensities up to those which resulted in a heart rate 70% maximal heart rate on placebo, and levelled off at higher intensities, while there was a progressive withdrawal of the parasympathetic activity. The ratio between heart rate predicted by the model and the recorded heart rate following placebo treatment tended to be less than 1.0 at lower exercise intensities, and approached the unit at intensities above those which resulted in a heart rate higher than 70% of maximal heart rate on placebo. There was a strong correlation (r=0.94,P<0.01) between the heart rate on placebo and the heart rate estimated by the model. Nevertheless, there was some scattering of the data around the identity line, with a standard error of the estimate for the regression line of 11 beats · min–1. Thus, during incremental exercise, the influence of sympathetic activity on heart rate does not become progressively more important at higher exercise intensities. The application of the Rosenblueth-Simeone model shows limitations during incremental exercise, particularly at low exercise intensities. 相似文献
6.
F. Lasbennes J. Seylaz 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1986,63(1):169-172
Summary The cerebrovascular consequences of the gentle restraint commonly used for the measurement of local cerebral blood flow (LCBF) in conscious rats has been tested by using two drugs, propranolol and diazepam. Propranolol induced small LCBF decreases in 7 structures suggesting that the cerebral circulation was partially controlled by the activation of intra or extracerebral aminergic pathways in this protocol. Sedative doses of diazepam reduced LCBF in most of the structures but anxiolytic doses increased it in 4 structures. This effect may be due to a regionally differentiated modification of activity in the brain due to the selective inhibition of limbic structures by diazepam. Since propranolol and diazepam induced only small changes, the LCBF of gently restrained rats appeared to be minimally affected by the stressful situation imposed by the protocol. 相似文献
7.
普萘洛尔、酚妥拉明对由去甲肾上腺素诱导的家兔肠系膜微血管运动的影响 总被引:1,自引:0,他引:1
应用显微录像静画步进法观察家兔肠系膜局部施加去甲肾上腺素(NA)后,诱寻出微动脉周期性、节律性的血管运动及静脉注入普萘洛尔、酚妥拉明对其产生的影响,以期探讨血管运动产生机制及其与α-,β-肾上腺素受体的关系。结果:在家兔颈动脉平均血压为11.40±0.89kPa的条件下,局部施予NA0.8μg于肠系膜观察域,引起微动脉的血管运动,其频率:0.109±0.006Hz,振幅:5.51±0.42μm。同一视野的微静脉和毛细血管未出现血管运动。血管运动的振幅在同一支微动脉上分布不均,呈节段性。普萘洛尔0.1mg/ml·kg-1、0.5mg/ml·kg-1组的内径、血压、血管运动频率及振幅无明显改变,1.0mg/ml·kg-1组的血压无明显变化,内径减小,血管运动频率增加,振幅减小。静脉注入酚妥拉明0.5mg/ml·kg-1及1.0mg/ml·kg-1,颈动脉血压降低,血管内径增加,血管运动频率减少,振幅降低,血管运动被抑制。结论:上述结果表明生理条件下,局部施加NA可以诱导出家兔肠系膜微动脉血管运动,并且血管运动的发生与NA及α-,β-肾上腺素受体有一定关系。 相似文献
8.
目的观察 7-氯苄基四氢巴马汀 ( 7-chlor -BTHP)对大鼠心肌肥厚和心室肌原纤维质膜Ca2 -Mg2 -ATP酶活力的影响。方法用L -甲状腺素诱发大鼠心肌肥厚 ,然后观察 7-chlor -BTHP对大鼠心肌肥厚及左心室肌原纤维Ca2 -Mg2 -ATPase的影响 ,以普萘洛尔 (Pro)作为阳性对照。结果经过 7-chlor-BTHP治疗 3天后 ,心肌肥厚明显改善 ,Ca2 -Mg2 -ATPase活力明显降低。结论 7-chlor-BTHP能明显消退L -甲状腺素诱发的大鼠心肌肥厚 ,并能显著降低心室肌原纤维膜Ca2 -Mg2 -ATPase酶活力。 相似文献
9.
J. A. G. Wijnen M. A. van Baak C. de Haan H. A. J. Struijker Boudier F. S. Tan L. M. A. B. Van Bortel 《European journal of clinical pharmacology》1993,45(2):101-105
Summary Inhibition of adipose tissue lipolysis may be involved in the impairment of endurance capacity after administration of a -adrenoceptor blocker. During endurance exercise, no significant decrease in plasma glycerol and free fatty acid (NEFA) concentrations after -adrenoceptor blockade is found. However, the levels during recovery from exhaustion are lower after -adrenoceptor blockade. This study was designed to investigate whether the lower levels after exercise are due to -adrenoceptor blockade or to the shorter time to exhaustion after administration of a -adrenoceptor blocker.In a single-blind study, 11 well-trained male subjects (age 23 (0.9) y) performed a cycle ergometer test at 70% Wmax until exhaustion 2 h after intake of 80 mg propranolol. One week later, the test was repeated after intake of placebo and was stopped at the time of exhaustion in the previous test. Average exercise time was 24 min. During exercise plasma glucose was lower, whereas plasma lactate and the respiratory exchange ratio were significantly higher when the subjects were on propranolol. Glycerol and NEFA concentrations during exercise were not significantly different between the two conditions. Despite an identical exercise time, glycerol and NEFA concentrations during recovery were significantly lower after propranol treatment.In conclusion, lipolysis is inhibited during exercise after propranolol, probably causing a shift from fat to carbohydrate combustion. 相似文献
10.
Summary Responsiveness to inhaled histamine and DL propranolol hydrochloride was measured in 31 adult asthmatics and compared with bronchoconstriction provoked by acute oral propranolol dosing (max 160 mg).Twelve asthmatics developed 15% reduction in the forced expired volume in 1 s (FEV1), 2 h after 100 mg oral propranolol; cardiac -adrenoceptor blockade was confirmed by cycle exercise tests in the 19 without airway response. The provocative inhaled dose of each aerosol causing a 20% fall in FEV1 (PC20) was lower, histamine 0.43 mg·ml–1, propranolol 3.12 mg·ml–1, in the 12 with a positive oral test compared with the 19 with a negative test, PC20 histamine 1.65 mg·ml–1, PC20 propranolol 16.2 mg·ml–1 (P < 0.001 for both aerosols). A correlation was demonstrated between the PC20 values for asthmatics with a negative oral test (r=0.72, P < 0.001, n=19) but not for the remainder (r=0.14, P > 0.05, n=12).Plasma propranolol concentrations (CL, ng·ml–1) after the final oral dose did not correlate with the % FEV1(26.3) (r=-0.28) when an airway response was provoked or with the reduction in exercise tachycardia (25.9%) (r=0.31) when no bronchoconstriction occurred. CL exceeded the limit of detection after the final inhaled propranolol dose (7.5 ng·ml–1) and was weakly related to the PC20 propranolol value (r=0.53, P=0.01, n=27). The prevalence of a positive oral challenge was low in this group (39%). APC20 propranolol value which was 100% sensitive as a predictor of a positive oral test had low specificity (58%) and a low predictive value (60%).This study has not found that nonspecific bronchial responsiveness to histamine or specific responsiveness to inhaled propranolol can be employed to predict bronchoconstriction in asthmatics following acute oral propranolol dosing. 相似文献