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31.
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
32.
J. Hasford 《European journal of neurology》2005,12(11):916-917
33.
采用一阶导数分光光度法测定醋酸曲安缩松注射液的含量,平均回收率为99.82%,RSD为0.39%。方法简便快速,结果满意。 相似文献
34.
M. Komulainen MD M. T. Tuppurainen H. Kröger A. M. Heikkinen E. Puntila E. Alhava R. Honkanen S. Saarikoski 《Osteoporosis international》1997,7(2):126-132
The study was designed to examine the effect of hormone replacement therapy (HRT) and low-dose vitamin D (Vit D) supplementation on the prevention of bone loss in non-osteoporotic early postmenopausal women and to determine whether Vit D supplementation can give additional benefit to an already optimized estrogen regimen. The effects of HRT and Vit D on bone mineral density (BMD) were studied in postmenopausal women in a 2.5-year randomized placebo-controlled study. The study population was a subgroup of the Kuopio Osteoporosis Risk Factor and Prevention Study (OSTPRE) (n=13100). A total of 464 early postmenopausal women were randomized to four groups: (1) HRT (a sequential combination of 2 mg estradiol valerate and 1 mg cyproterone acetate (E2Val/CPA); (2) vitamin D3 (cholecalciferol, 300 IU/day); (3) HRT+Vit D; and (4) placebo (calcium lactate; 93 mg Ca2+/day). Lumbar (L1–4) and femoral neck BMD were determined by dual-energy X-ray absorptiometry before and after 2.5 years of treatment. After 2.5 years, lumbar BMD had increased by 1.8% in the HRT group (p<0.001) and by 1.4% in the HRT+Vit D group (p=0.002), whereas lumbar BMD had decreased by 3.5% (p<0.001) in the Vit D group and by 3.7% (p<0.001) in the placebo group. The loss of femoral neck BMD was lower in the HRT (–0.3%) and the HRT+Vit D (–0.9%) groups compared with the Vit D (–2.4%) and the placebo groups (–3.7%). This study confirms the beneficial effect of HRT on BMD. It also shows that low-dose vitamin D supplementation has only a minor effect in the prevention of osteoporosis in non-osteoporotic early postmenopausal women and does not give any benefit additional to that of HRT alone. 相似文献
35.
Roelf Valkema MD Berthe L. F. van Eck-Smit MD Ernst E. van der Wall MD 《Journal of nuclear cardiology》1994,1(6):546-560
Noninvasive techniques for the assessment of cardiac metabolism are important for the detection of potentially salvageable
tissue in jeopardized areas of the myocardium. The correct identification of hibernating and stunned myocardium in patients
with severely depressed cardiac function can have vital therapeutic consequences for the patient. Changes in myocardial fatty
acid and glucose metabolism during acute and prolonged ischemia can be traced by positron-emitting or gamma-emitting radiopharmaceuticals.
Alternatively,31P-labeled magnetic resonance spectroscopy can be used for the assessment of high-energy phosphate metabolism. It is not yet
clear which modality will emerge as the most useful in the clinical setting. Positron emission tomography (PET) that uses
combinations of flow tracers and metabolic tracers offers unique opportunities for quantification and high-resolution static
and rapid dynamic studies. Currently, assessment of glucose metabolism with18F-fluorodeoxyglucose is regarded as the gold standard for myocardial viability and prediction of improvement of impaired contractile
function after revascularization. However, preserved oxidative metabolism may be required for potential functional improvement,
and therefore assessment of residual oxidative metabolism by11C-labeled acetate PET may prove to be more accurate than18F-fluorodeoxyglucose PET, which reflects both anaerobic and oxidative metabolism. Moreover, because fatty acids are metabolized
only aerobically, they are excellent candidates for the clinical assessment of myocardial viability and prediction of functional
improvement after revascularization. Especially derivatives of fatty acids that are not metabolized but accumulate in the
myocyte are attractive for myocardial imaging. Examples are123I-beta-methyl-p-iodophenyl pentadecanoic acid and 15-(o-123I-phenyl)-pentadecanoic acid. These tracers can be detected by planar scintigraphy and single-photon emission computed tomography,
which are more economical and widely available than PET. In addition, 511 keV collimators have been developed recently, making
the detection of positron emitters by planar scintigraphy and single-photon emission computed tomography feasible. The experience
with31P-labeled magnetic resonance spectroscopy in humans is still limited. With current magnetic resonance spectroscopic techniques,
insufficient spatial resolution is achieved for clinical purposes, but the possibility of serial measurements to monitor rapid
changes of phosphate-containing molecules in time makes magnetic resonance spectroscopy very valuable for the research of
myocardial metabolism. 相似文献
36.
目的:探讨中国妇女哺乳期使用迪波盖司通后血清和乳液醋酸甲羟孕酮(MPA)浓度变化。方法:10名产后哺乳妇女单次注射迪波盖司通(含MPA150mg),在注射后的第1、2、4、6、8、10和12周采集血样和乳液样本,用放射免疫方法测定MPA。结果:血清MPA浓度于注射后第1周最高,到第2、4周时下降明显,第4周后浓度下降趋势逐渐缓慢。乳液MPA浓度在第1周为最高,第2周比第1周降低了约1/2,之后10周平均浓度变化波动在5.09-8.15ng/ml之间。观察期间乳液/血清MPA浓度比值和曲线下浓度面积比值均为0.55。对象之间和同一对象不同时间点乳液/血清MPA浓度存在明显个体差异。结论:哺乳期使用迪波盖司通,将导致血液和乳液中含有一定量的MPA。 相似文献
37.
利用人T淋巴母细胞(Jurkat)细胞系作为研究对象。企图探探索细胞外基质成份及肌醇磷脂细胞信息传递系统与细胞移动的关系。研究结果表明:当细胞被伏波醇酯(PMA)处理过后,其粘连性与移动件对纤维连结蛋白(FN)底物的反应在已是高水平的基础上有更进一步提高的作用。与FN刊相反的是,未经PMA处理处的Jurkat细胞对层粘连蛋白(Lm)底物却无明显的粘连性及移动性增加的反应,尽管在PMA处理过4小时内亦无任何的增强。但是,当PMA作用于细胞24一48小时后则明显池增加其Lm底物的粘连性及移动性反应,表明了其明显的协同作用。分别用抗FN、抗Lm及蛋白激酶C抑制剂Staurosprine(SP)时均起到特异性的抑制作用。可见,协同作用的产生是通过蛋白激酶C激活后的-段时间内,使细胞表面Lm受体密度增加而对底物Lm反应增强所致。 相似文献
38.
考察了头孢哌酮钠在醋酸钠平衡液中的稳定性。二药配伍后,置室温(25℃)及37℃水浴中,6h内溶液无颜色改变,亦无沉淀、气体产生,头孢哌酮钠均在初始浓度的95%以上。 相似文献
39.
Roland Seifert Rahel Burde Günter Schultz 《Naunyn-Schmiedeberg's archives of pharmacology》1989,340(1):101-106
Summary There are controversial reports in the literature concerning the effects of opioids on superoxide (O
2
–
) formation in phagocytes, these agents being either inhibitory or stimulatory. We re-examined this issue and compared the effects of the Chemotactic peptide, N-formyl-l,-methionyl-l-leucyl-l-phenylalanine (fMet-Leu-Phe), phorbol myristate acetate (PMA), ATP, platelet activating factor (PAF), cytochalasin B (CB) and prostaglandin E1 (PGE1) with those of various opioids on O
2
–
formation in human neutrophils and HL-60 leukemic cells under defined experimental conditions. In the presence of CB, fMet-Leu-Phe and PAF concentration-dependently activated O
2
–
formation in neutrophils with EC50 values of 20 nM and 100 nM, respectively. In the absence of CB, fMet-Leu-Phe and PAF were much less effective. PAF synergistically enhanced O
2
–
formation induced by fMet-Leu-Phe. ATP at a concentration of 100 M and the opioids, methionine enkephalin, -endorphin, dynorphin, [d-Ala2, N-Me-Phe4, Gly5-ol]-enkephalin, [d-Ala2-d-Leu5]-enkephalin and morphine at concentrations between 10 pM to 1 M did not activate O
2
–
formation. ATP but not \-endorphin potentiated fMet-Leu-Phe-induced O
2
–
formation. O
2
–
formation induced by a maximally stimulatory concentration of PMA (100 ng/ml) was enhanced by fMet-Leu-Phe but was unaffected by methionine enkephalin or PGE1. PMA at a non-stimulatory concentration (2 ng/ml) potentiated the effect of fMet-Leu-Phe but did not induce responsiveness to PAF, ATP or -endorphin. PGE1 strongly inhibited fMet-Leu-Phe-induced O
2
–
formation, whereas morphine, methionine enkephalin and the opioid antagonist, naloxone, were without effect. In HL-60 cells differentiated with dibutyryl cAMP, fMet-Leu-Phe, PAF and ATP but not -endorphin activated O
2
–
formation. Our results show that O
2
–
formation is differentially regulated by various classes of intercellular signal molecules and that opioids do not play a role in the regulation of O
2
–
formation. The precise definition of the experimental conditions and control experiments with established modulators of O
2
–
formation are essential to evaluate the role of opioids in the regulation of this effector system.Send offprint requests to R. Seifert at the above address 相似文献
40.
Satoshi Mochida Itsuro Ogata Yasuhiko Ohta Teruaki Oka Kenji Fujiwara 《Pathology international》1991,41(3):217-220
In order to investigate superoxide production by pulmonary macrophages in the rat, a route was created by ligating both the inferior and superior venae cavae and resecting the aorta after cannulation through the inferior vena cava into the right atrium of the heart. Lung perfusion was performed via this route with nitro blue tetrazolium. Although there was no formazan deposition throughout the lung, it became detectable in both alveolar and interstitial macrophages when phorbol myristate acetate was added to the perfusate. This deposition was markedly enhanced by previous injection of Corynebacterium parvum. The deposition disappeared after further addition of Cu(Lys)2 , a scavenger of superoxide anions. This procedure may be useful for estimating in situ the ability of pulmonary macrophages to produce superoxide in the rat. 相似文献