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1.
2.
利用LC-MS/MS法快速鉴定盐酸头孢吡肟中的同分异构体杂质   总被引:5,自引:0,他引:5  
目的建立应用LC-MS/MS技术快速鉴定盐酸头孢吡肟原料药中的同分异构体杂质的方法。方法以乙腈-10 mmol·L-1乙酸铵(5∶95)为流动相经C18柱分离,通过电喷雾串联质谱在线检测,获得相关的色谱和质谱信息。结果在所建立的条件下,盐酸头孢吡肟及其同分异构体杂质获得有效分离,主成分和其同分异构体杂质的保留时间分别为15.28 min和9.18 min,同时它们的二级质谱产物离子信息及其裂解方式呈现明显的差异。结论本法能快速、准确地分离鉴定盐酸头孢吡肟原料药中的同分异构体杂质,从而可以对其原料药进行质量控制。  相似文献   
3.
Antioxidant properties of ursodeoxycholic acid   总被引:5,自引:0,他引:5  
We have investigated potential antioxidant properties of the clinically relevant bile acid UDCA, which reaches therapeutic concentrations up to 0.09 and 29 mM, respectively, in human plasma and bile. UDCA was an excellent scavenger of OHz.rad; generated by FeCl(3)-EDTA, H(2)O(2) and ascorbate in the deoxyribose oxidation test, showing IC(min) and IC(50) values of 0.02 and 0.2 mM, respectively, and a second-order rate constant for reaction with OHz.rad; of 2+/-0.1 x 10(10)M(-1)s(-1). Notably, the drug could enhance at 1.5 mM concentration the antioxidant capacity of human bile against OHz.rad;-induced deoxyribose oxidation. UDCA also showed antioxidant effects in the deoxyribose test performed with nonchelated iron ions, such as Fe(2+) plus H(2)O(2) (IC(min): 7 mM, IC(50): 20 mM) or Fe(3+) plus H(2)O(2) and ascorbate (IC(min): 0.3 mM, IC(50): 5 mM), and inhibited ferrozine-Fe(2+) and desferrioxamine-Fe(3+) complexes formation with IC(50) values of, respectively, 12 and 0.3 mM, indicating that the drug interacts more with iron(III) than with iron(II). Moreover, UDCA significantly inhibited phospholipid liposome peroxidation induced by the OHz.rad;-generating system FeCl(3)-EDTA, H(2)O(2) and ascorbate (IC(min): 0.75 mM, IC(50): 3 mM), and by peroxyl radicals generated in the aqueous phase by AAPH (IC(min): 8 mM, IC(50): 14 mM). UDCA, even at 25 mM concentration, was ineffective on the lipoperoxidation mediated by Fe(2+) alone, but at the same concentration counteracted significantly that by Fe(3+) plus ascorbate, further pointing to its preferential antioxidant interaction with iron(III).In conclusion, UDCA has direct antioxidant properties, which are especially relevant against Fe(3+)- and OHz.rad;-dependent biomolecular oxidative damage; such properties are evident at therapeutically relevant drug concentrations, suggesting that UDCA could act as an antioxidant in vivo.  相似文献   
4.
2-溴-4-硝基甲苯经催化氢化、与水合氯醛和盐酸羟胺反应、环合制得4-溴-5-甲基靛红,再经Baeyer-Villiger反应、甲酯化、与盐酸氯甲脒环合、Ullmann反应、成盐结晶制得胸苷酸合成酶抑制剂盐酸诺拉曲塞二水合物,总收率为8%。  相似文献   
5.
报道了盐酸普拉克索降解杂质BI-IO460BS的合成方法.焦谷氨醇经对甲苯磺酰氯取代、氰化钾氰化、碘丙烷N-丙基化、氰解并甲酯化、氧硫交换、氨腈取代、水解得BI-IO460BS.反应总收率为5.9%,并经MS和1H NMR等进行了结构确证.  相似文献   
6.
叶有清 《药学进展》2014,(6):450-453
目的:考察普拉克索添加艾司西酞普兰治疗对帕金森病患者非运动症状的临床疗效。方法:将60例帕金森病患者按收治顺序单双号分为观察组和对照组,每组30例。对照组采用口服盐酸普拉克索治疗,观察组则在口服盐酸普拉克索基础上添加艾司西酞普兰治疗,连续治疗8周后,分别以帕金森病综合评分量表(UPDRS)、汉密尔顿抑郁量表(HAMD)、汉密尔顿焦虑量表(HAMA)、匹兹堡睡眠质量指数(PQSI)和生活质量综合评定量表(GQOLI-74)的评分为指标,对比考察2组患者的综合症状、抑郁和焦虑症状、睡眠和生活质量等的变化。结果 :与治疗前相比,2组患者治疗后,UPDRS总分、运动检查以及精神、行为和情感评分均显著降低(P〈0.05),治疗并发症和日常生活评分无显著差异(P〉0.05),其中观察组患者的UPDRS总分以及精神、行为和情感评分较对照组显著降低(P〈0.05),而2组患者的治疗并发症、日常生活和运动检查评分无显著差异(P〉0.05);且2组患者治疗后,HAMD、HAMA和PQSI评分均显著降低(P〈0.05),其中观察组患者的HAMD、HAMA和PQSI评分较对照组显著降低(P〈0.05),而2组患者的GQOLI-74评分均显著升高(P〈0.05),其中观察组患者GQOLI-74评分显著高于对照组(P〈0.05)。结论 :普拉克索添加艾司西酞普兰治疗可有效改善帕金森病患者抑郁、焦虑、睡眠障碍等非运动症状,从而提高患者生活质量,具有重要的临床意义。  相似文献   
7.
盐酸普拉克索B晶型的制备和表征   总被引:2,自引:2,他引:0  
目的 制备盐酸普拉克索的B晶型并优化制备工艺,同时进行结构表征和稳定性研究。方法 制备盐酸普拉克索的B晶型,采用热重法(TGA)、差示扫描量热法(DSC)、X射线粉末衍射(PXRD)、X射线单晶衍射(SXRD)等分析手段,对盐酸普拉克索B晶型进行表征研究。结果 制备得到了盐酸普拉克索B晶型,其晶型属正交晶系,空间群P212121,结构中不含溶剂(包括水)。盐酸普拉克索B晶型热处理后晶型不发生转变。结论 盐酸普拉克索B晶型为无水晶型,热稳定性优于一水合物晶型,具有高温稳定性。  相似文献   
8.
Objective: Investigate safety, feasibility and efficacy of switching therapy in patients with advanced-stage Parkinson’s disease (PD) inadequately controlled with pramipexole (≤ 3.5 mg/day) or ropinirole (≤ 14 mg/day) to rotigotine transdermal system (≤ 14 mg/24 h; dose adjustments ≤ 16 mg/24 h permitted).

Methods: PD0009 (ClinicalTrials.gov: NCT01711866) was an open-label study in patients with advanced-stage PD receiving levodopa, and experiencing sleep disturbance or early-morning motor impairment. Pramipexole/ropinirole was switched to equivalent dose rotigotine overnight or in two stages. During the 4-week treatment period rotigotine dose adjustments were permitted (up to 16 mg/24 h). Primary variable: Clinical Global Impressions (CGI) item 4: side effects (assessing safety) at end of treatment.

Results: 79/87 (91%) patients completed the study; 2 (2%) withdrew due to adverse events (AEs). Most (84; 97%) had CGI item 4 score < 3 indicating switch did not interfere with functioning; three experienced drug-related AEs interfering with functioning (score = 3). 62% patients improved on Patient Global Impression of Change, assessing effectiveness. AEs occurring ≥ 5%: application site pruritus (10%), application site erythema (7%), dizziness (7%), dyskinesia (7%), erythema (6%), pruritus (6%). Unified Parkinson’s Disease Rating Scale II and III, Parkinson’s Disease Sleep Scale-2 and Pittsburgh Sleep Quality Index were unchanged. Numerical improvements in ‘off’ time, awakenings and nocturias were observed.

Conclusions: Switch from pramipexole or ropinirole to rotigotine (up to 14 mg/24 h) was feasible and possibly associated with some benefit.  相似文献   

9.
Previous studies have shown that the effects of manual acupuncture (MA) are contributed by collagen fibers and mast cells in local acupoints, at which acupuncture stimulation causes various afferent fiber groups to be excited. However what happens in local nerve fibers and mast cells after MA remains unclear. The aim of this study was to examine the response of cutaneous nerve fibers and mast cells to MA stimulation in acupoint Hegu (LI4). The contralateral LI4 of the same rat was used as a non-stimulated control. Immnohistochemistry analysis were carried out to observe the expression of histamine (HA), serotonin (5-HT) and nociceptive neuropeptides, calcitonin gene-related peptide (CGRP) and substance P (SP), in the LI4 area. Mast cells were labeled with anti-mast cell tryptase antibody and simultaneously with HA or 5-HT primary antibodies to observe their co-expression. Our results showed that SP and CGRP were expressed more highly on the cutaneous nerve fibers of LI4 after MA stimulation than that of the control. Mast cells aggregated in close proximity to the blood vessels in intra-epidermis and dermis and some of them with degranulation in the lower dermis and subcutaneous tissue of LI4. Both mast cells and their granules appeared with HA (+) and 5-HT (+) expression at stimulated L14 sites, while a few intact mast cells with a little expression of 5-HT and HA were distributed in areas of non-stimulated L14. The results indicated that local cutaneous nerve terminals and mast cells responded to MA with higher expression of SP and CGRP in nerve fibers, as well as with aggregation and degranulation of mast cells with HA and 5-HT granules at acupoint LI4. These neuroactive substances may convey signals to certain pathways that contribute to the effects of acupuncture.  相似文献   
10.
BACKGROUND: To determine whether diabetic nephropathy is a risk factor for silent cerebral infarction and whether antiplatelet drug dilazep dihydrochloride decreases the occurrence of silent cerebral infarction in type 2 diabetes patients with microalbuminuria. METHODS: Two hundred four type 2 diabetes patients (124 men, 80 women; age, median 56 years, range 42-74 years) and 60 healthy age-matched subjects (no diabetes, normal renal function) were recruited for brain magnetic resonance imaging. The diabetes patients included 40 without nephropathy (group A), 42 with microalbuminuria (20-200 microg/min) (group B), 44 with macroalbuminuria (>200 microg/min) and normal renal function (blood creatinine <132.7 micromol/L) (group C), 33 with chronic renal failure but not undergoing haemodialysis (blood creatinine >132.7 micromol/L; mean creatinine 335.9 micromol/L) (group D) and 45 undergoing haemodialysis (duration; median 4 years, range 3-6 years) (group E). RESULTS: Silent cerebral infarction was found in 20, 29, 34, 45, 53 and 8% of group A, B, C, D, E and control patients respectively. The incidence of silent cerebral infarction was increased with diabetic nephropathy. Thirty group B patients with no silent cerebral infarction were divided into two groups: (B1) 15 treated with dilazep dihydrochloride and (B2) 15 not treated with dilazep dihydrochloride. Treatment continued for 24 months. The incidence of silent cerebral infarction was significantly lower in the dilazep-treated patients (6.7%) than in the untreated patients (33.3%) (p < 0.01). CONCLUSIONS: These data suggest that diabetic renal dysfunction increases the risk of silent cerebral infarction and that dilazep dihydrochloride prevents its onset in early type 2 diabetic nephropathy patients.  相似文献   
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