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61.
HPLC法同时测定复方雌二醇控释贴片中雌/孕激素的含量   总被引:2,自引:0,他引:2  
目的:建立同时测定复方雌二醇透皮控释巾片中雌二醇(E2)和炔诺酮醋酸酯(NETA)含量的反相HPLC法。方法:色谱柱为岛津柱(5μm,6.0mm*150mm)检测波长为280mm(0--8.5min),240nm(8.51--15min);流动相为甲醇-水(75:25)。结果:E2、NETA线性范围分别为2.0~20、6.0~60mg.L^-1。平均回收率分别为101.0%(RSD=1.6%)、99  相似文献   
62.
Summary Adriamycin (Adr), the single most active agent used in the treatment of breast cancer, may become ineffective as treatment progresses due to the development of multidrug resistant (MDR) tumors. A major mechanism associated with MDR is increased P-glycoprotein (Pgp) expression. This study examined the abilities of the anti-estrogen tamoxifen (TAM) and the progestin medroxyprogesterone acetate (MPA) as well as cyclosporin A (CsA), a known resistance modifier, to enhance the cytotoxic effects of Adr on human breast epithelial cells (HBEC) in primary culture. Pgp and estrogen receptor (ER) expression were determined in each of the cultures by immunocytochemical assays using the monoclonal antibodies C219 and H222 Sp, respectively. The Adr-sensitive, Pgp-, ER+ MCF-7 cell line and the Adr-resistant, Pgp+, ER-MCF7-AdrR cell line were used as controls. Primary cultures were categorized as HBEC from tissues with or without previous chemotherapy. Pgp was detected in 1 of the 15 cell cultures from tissues without previous chemotherapy and in 5 of the 6 cell cultures from tissues previously exposed to chemotherapy. Incubation with either CsA or MPA plus Adr enhanced Adr toxicity in Pgp+ but not Pgp- cell cultures, whereas TAM had no effect on the sensitivity of any of the cultures. Of the 21 primary cultures of HBEC, 3 were ER+. There was no correlation between the enhancement of Adr cytotoxicity and ER status. The data suggest that MPA as well as CsA may be useful as modifying agents in overcoming Pgp-associated multidrug resistance.  相似文献   
63.
Following subacute intoxication of rats with Pb-, Cu-, and Zn-salts (separately or in mixture) for 5 weeks, the chelating agent D-penicillamine was administered for 3 weeks. In the course of the 3-month experiment, lactate dehydrogenase (LDH) was estimated in serum and in cytoplasmic fraction of the kidney. Pb2+ treatment resulted in an increase of LDH activity, Cu2+ in a slight decrease, whereas Zn2+ had no effect, respectively. Mixture of these metals caused a significant rise in the enzymatic activity. Seven weeks after the stoppage of the administration of toxic substances, altered LDH activity, both in serum and in kidney returned to normal. D-penicillamine treatment was found to accelerate a restoration of the enzyme activity.In the experiments in vitro, Cu2+ inhibited significantly the kidney LDH activity, Pb2+ and Zn2+ being 100- and 400-times less efficient, respectively. Cu2+ inhibition was reversed by D-penicillamine, whereas inhibition of LDH by Zn2+ or Pb2+ was irreversible.  相似文献   
64.
The effect of early splenectomy and of polychemotherapy with hydroxyurea, busulfan, and alternate bimonthly courses of arabinosyl cytosine and vincristine plus prednisone, was evaluated in 139 previously untreated patients with chronic myeloid leukemia (CML), consecutively admitted to 18 hospitals from March 1973 to October 1974. Fifty-six patients were splenectomized and 83 patients were not splenectomized. Splenectomy did not influence the duration of chronic and blastic phase, and did not prolong survival. The prognosis of high risk patients was not improved. During the chronic phase, high platelet counts were more frequent in splenectomy group, and five patients developed thrombotic or thromboembolic complications, 5 to 19 months after the operation. The median survival of the whole group was 50 months, with 32 of 139 patients (actuarial proportion 30%) remaining alive 72 months after diagnosis, but the slope of the survival curve was similar to that of historical controls. The results of this trial suggests that new strategies should be developed for the therapy of CML.  相似文献   
65.
Summary The plasma binding of prednisolone was studied in twenty normal volunteers and twenty rheumatoid arthritis patients. An in vitro assessment of the binding following the addition of prednisolone, prednisone, and hydrocortisone to the plasmas obtained from the subjects showed significant differences in the percentage of prednisolone bound. However, the differences observed were regarded as clinically insignificant. The plasma protein binding was determined by an in vitro equilibrium dialysis of the individual plasma samples at 37° C. Prednisolone levels on both sides of the dialysis membrane were determined using radioactivity and HPLC analytical methodologies. The percentages of prednisolone bound calculated from the analytical results of either the radiochemical or HPLC method were not significantly different. The change in the percentage of prednisolone bound to plasma proteins was studied as a function of the total prednisolone plasma concentration in a normal volunteer and in a systemic lupus erythematosis patient. As a result of prednisolone binding to both transcortin and albumin, the binding of prednisolone changes as a function of prednisolone concentration. The binding data were fitted using nonlinear least squares regression, and the affinity constants for the binding of prednisolone to transcortin and albumin were estimated.  相似文献   
66.
The reversal learning capacity of young rhesus monkeys in visual discrimination tasks was examined during daily exposure to dietary lead acetate throughout the first year of life. While not affected in physical development, all lead-treated monkeys showed performance deficits on reversal learning tasks. These deficits were independent of lead-induced changes in motivation. Over a series of problems, the overall learning rate of monkeys with blood lead concentrations in the range of 70-90 microgram/dl was retarded, which resulted partly from a pronounced difficulty in attaining criterion on the first of a series of reversals within a given problem. This latter deficit resulted from an increase in errors, balks, and total trials to criterion on the first reversal. Monkeys exposed to blood lead concentrations of 40-60 microgram/dl required significantly more trials to finish all problems, but did not show the first-reversal deficit. Theoretical implications of these data were discussed.  相似文献   
67.
目的:研究冰醋酸涂剂的稳定性。方法:采用酸碱中和分析法和气相色谱法分别对醋酸与其不稳定产物乙酸乙酯运行定量测定。结果:在放置过程中醋酸含量下降,而乙酸乙酯含量增加。结论:《中国医院制剂规范》第2版收载的冰醋酸涂剂不稳定。  相似文献   
68.
HPLC测定复方松泰洗剂中醋酸氯己定含量   总被引:5,自引:0,他引:5  
张启明  谭生建 《中国药事》2003,17(7):441-442
建立HPLC法测定复方松泰洗剂中醋酸氯己定的含量。用YWGC18柱 ,以乙腈 -水 -三乙胺 (2 9∶71∶0 5 ,用磷酸调pH至 3 0 )为流动相 ,流速 1ml·min- 1,检测波长 2 5 4nm。醋酸氯己定在 0 716~ 3 5 8μg范围内线性关系良好 ,r =0 9998,平均回收率 99 2 %。本法适用于复方松泰洗剂的质量控制。  相似文献   
69.
王世刚 《安徽医药》2003,7(3):208-209
目的 寻找醋酸地塞米松片含量均匀度测定时紫外波长偏离的原因。方法 用紫外分光光度法测定含量均匀度测定液的最大吸收波长值 ,对超出药典规定范围的测定液用高效液相色谱法分离 ,观察有无杂质出现。色谱柱为Elit testODS柱 (2 4 0mm× 4 6mm) ,流动相 :甲醇 -水 (70∶30 ) ,检测波长 2 4 0nm。同时用离心法考察辅料对波长偏离的影响。结果 主药中含有的杂质和辅料使醋酸地塞米松片含量均匀度紫外测定波长偏离。结论 用HPLC测定醋酸地塞米松片含量均匀度可避开波长偏离的干扰 ,使结果准确  相似文献   
70.
复方替硝唑含漱液的制备与含量测定   总被引:1,自引:0,他引:1  
娄月芬 《医药导报》2003,22(11):809-810
目的:制备复方替硝唑含漱液,建立其含量测定方法并进行稳定性研究.方法:采用最大吸收波长法测定替硝唑的含量,用双波长等吸收点法测定醋酸氯己定的含量,恒温加速试验法考察稳定性.结果:替硝唑回归方程为C=-0.039 68+27.491 A,r=0.999 9,醋酸氯己定回归方程为C=0.062 47+50.454 8△A,r=0.999 99,精密度和回收率良好,置65℃(96 h),70℃(72 h),75℃(48 h)恒温水浴中加热,含量无明显下降.结论:复方替硝唑含嗽液制备方法简单,含量测定方法简便且稳定性好.  相似文献   
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