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21.
J. Guay P. Gaudreault A. Boulanger A. Tang L. Lortie C. Dupuis 《Acta anaesthesiologica Scandinavica》1992,36(7):722-727
Twenty-six patients, ASA physical status 1, scheduled for elective cesarean section, were divided at random into two groups and received via an epidural catheter 20 ml of 2.2% lidocaine hydrocarbonate (17.3 mg.ml-1 lidocaine base) with 5 micrograms.ml-1 epinephrine freshly added (Group CO2 = 13 patients) or 20 ml of 2% lidocaine hydrochloride (17.3 mg.ml-1 lidocaine base) also with 5 micrograms.ml-1 epinephrine freshly added. Following clampage of the umbilical cord (at 40.1 +/- 4.9 min after the injection of lidocaine for the CO2 group and at 41.0 +/- 5.4 min for the HCl group), serum concentrations of lidocaine were measured both in the mother and in the umbilical vein. All newborns were examined by the same blinded pediatrician with Apgar scores at 1, 5 and 10 min and with Neurobehavioral Adaptive Capacity Scores (NACS) at 15 min, 2 h and 24 h. The concentrations of lidocaine in the serum were comparable in both groups: in the mothers 8.61 +/- 1.48 mumol.l-1 for the CO2 group vs 8.04 +/- 2.36 mumol.l-1 for the HCl group and in the newborns 3.86 +/- 0.84 mumol.l-1 for the CO2 group vs 3.92 +/- 0.95 mumol.l-1 for the HCl group. The ratio of umbilical vein to maternal vein concentrations of lidocaine was also similar in both groups: 0.45 +/- 0.07 for the CO2 group vs 0.54 +/- 0.24 for the HCl group. The percentage of newborns with a normal NACS (score > or = 35/40) was equal in both groups, i.e. 91% at 15 min and 2 h of life and 100% at 24 h of life.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
22.
S. Kudo K. Umehara Yoshifumi Abe Masayuki Furukawa Masaaki Odomi 《Psychopharmacology》1997,131(4):388-393
To elucidate the penetrability of carteolol, a β-adrenoceptor antagonist (β-blocker) into the brain of rats, intracerebral
and serum concentrations of the compound were determined in male rats receiving single or repetitive oral administration of
carteolol hydrochloride at 30 mg/kg. The time-course of the intracerebral concentration of carteolol following single IV administration
of the compound at 10 and 30 mg/kg was also studied in male rats. A high-performance liquid chromatography method was used
to determine the intracerebral and serum concentrations. Following single oral dosing, the intracerebral concentration of
carteolol reached a maximum of 0.074 μg/g at 2 h postdosing and declined with a half-life of 3.7 h, and the Cmax and AUC of carteolol in the brain were 12.5% and 19.8% of those in serum. The intracerebral and serum concentrations of carteolol
were determined in male rats receiving repetitive oral dosing of the compound once daily for 7 days. The concentration of
carteolol in the brain and serum at 1 h postdosing varied within a range of 0.059–0.091 μg/g and 0.321–0.443 μg/ml, respectively,
throughout the dosing period, showing no changes in the penetrability of the compound into the brain due to repeated dosing.
The concentration of carteolol in the brain and serum increased in a dose-dependent manner in rats receiving a single IV administration
of the compound. The elimination half-life of carteolol in the serum and brain was 0.6–0.8 h and 1.3–1.7 h, respectively,
in rats following single IV dosing of the compound. The half-life in the brain was about twice as long as that in the serum.
The brain to serum concentration ratio was 0.306:0.499. From the above results, it was concluded that carteolol is distributed
from the circulation to the brain with low penetrability.
Received: 30 October 1996/Final version: 16 December 1996 相似文献
23.
目的建立HPLC法测定复方氨酚苯海拉明片中盐酸麻黄碱和盐酸苯海拉明的含量。方法用Kromasil C18(250 mm×4.6 mm,5μm)色谱柱;流动相甲醇-乙腈-1%十二烷基硫酸钠溶液(26∶32∶42)(冰醋酸调pH值3.1),检测波长257 nm。结果线性范围,盐酸麻黄碱:1.228 8~11.059 2μg,r=0.999 9,盐酸苯海拉明:1.216 8~10.951 2μg,r=1.000 0;平均回收率,盐酸麻黄碱98.79%,RSD%=0.59%,盐酸苯海拉明100.44%,RSD%=0.57%。结论本方法简便、准确、灵敏度高、重现性好,可更好地控制本品的质量。 相似文献
24.
目的:探索固体自乳化释放药系统,研制自乳化缓释片,考察体外释药行为。方法:以盐酸维拉帕米(Verpamil Hydrochloride,VH)为模型药物,以吐温80(Tween80),豆磷脂(sbpc)为乳化剂,以羟丙甲纤维素(HPMC),卡波普(carbopol)为骨架材料,制备自乳化缓释片。结果:以含吐温80和豆磷脂10%,羟丙甲纤维素和卡波普30%的处方乳化效果好,体外释药符合要求。结论:通过调节乳化剂和骨架材料的比例,可以获得理想的自乳化固体缓释制剂。 相似文献
25.
26.
甲基黄酮醇胺盐酸盐对异丙肾上腺素正性频率作用的影响 总被引:2,自引:0,他引:2
本文比较了甲基黄酮醇胺盐酸盐(MFOA)、普萘洛尔(Pro)、维拉帕米(Ver)对异丙肾上腺素(Iso)所致兔离体右心房正性频率作用的影响。Pro使Iso累积浓度反应曲线平行右移,不抑制最大反应,属于典型的竞争性抑制剂,其pA2=8.43;MFOA和Ver使Iso量效曲线向下右移,抑制最大反应,为非竞争性拮抗。MFOA(2×10~(-5)M)和Ver(2×10~(-7)M)分别使最大反应下降19.28%和48.57%,其pD'2值分别为4.07±0.14、6.68±0.15。结果表明MFOA的作用不同于Pro,和Ver相似。 相似文献
27.
A number of factors affecting the stability of propranolol HC1 during electrophoretic control were investigated. It was found that significant degradation of propranolol HC1 and hydrolysis of water occurred when a current of 15 mA was used with platinized electrodes. This degradation was thought to be due to decomposition of propranolol HC1 at the electrodes. Degradation could be significantly reduced by using uncoated platinum electrodes and currents in the range of 0 to 2.5 mA, while still allowing control of drug delivery rates. Electrode reaction processes were found at high ionic strengths and high drug concentrations but were not thought to be associated with drug decomposition. 相似文献
28.
目的 :根据盐酸地尔硫 艹卓 与溴甲酚绿形成有色离子对的性质 ,建立酸性染料法测定盐酸地尔硫 艹卓 及其片剂的方法。方法 :盐酸地尔硫 艹卓 与溴甲酚绿形成有色离子对络合物用氯仿萃取后比色。结果 :最大吸收波长λmas=(415±1)nm ,A -C回归方程为 :A =0 0 4 37C - 10 3 r=0 9996 (n =3) ,线性范围为 6 μg/ml~ 18μg/ml。结论 :该法灵敏准确 ,专属性强 ,便于普及 相似文献
29.
30.
复方盐酸伪麻黄碱缓释片的研究 总被引:1,自引:0,他引:1
应用反相HPLC法测定血药浓度,对复方盐酸伪麻黄碱缓释片的体外溶出及兔灌服一次的药物动力学进行了研究,并与自制普通片进行对照。结果表明缓释片维持体内有效血药浓度的时间较长,其相对生长利用度为122.48%。体内外显著相关。理论值与实测值基本相符。 相似文献