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目的建立了一种高效液相色谱-三重四极杆串联质谱法,对氯沙坦钾原料药中遗传毒性杂质N-亚硝基-N-甲基-4-氨基丁酸(NMBA)进行测定。方法色谱柱为岛津Shim-pack XR-ODSⅡ色谱柱(2.0 mm×150 mm,2.2μm),流动相为0.1%甲酸水溶液(A)和甲醇(B),进行梯度洗脱,流速0.3 mL·min^-1,柱温为40℃,采用ESI离子化-三重四极杆质谱多反应监测(MRM)正离子模式检测,碰撞电压分别为-11,-13和-13 V,碰撞气氩气270 kPa,NMBA的离子对分别为m/z 147.15→117.10,147.15→87.10和147.15→44.10。结果该方法中NMBA在1~100 ng·mL^-1内线性关系良好,日内和日间的保留时间和峰面积的重复性良好(RSD均小于1.10%,n=6和n=18),低、中、高3个浓度的平均回收率在94.40%~98.04%之间。结论本方法简单方便,可快速有效的对氯沙坦钾原料药中NMBA进行限度检查并实现定量分析。  相似文献   
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Summary— KR31080 (2-butyl-5-methyl-6-(1-oxopyridin-2-yl)-3-[[2'-(1H-tetrazol-5-yl) biphenyl-4-yl]methyl]-3H-imidazo[4,5-b] pyridine) is a potent inhibitor of angiotensin type 1 (AT1) receptors in rabbit aorta and human recombinant AT1 receptors. In the isolated rabbit thoracic aorta, KR31080 caused a nonparallel shift to the right of the concentration-response curves to angiotensin II (All) with decreased maximal response (pD'2 = 10.1 ± 0.1), but had no effect on the contractile response induced by norepinephrine. KR31080 inhibited specific [125I]AII binding to rabbit aortic membranes (AT, receptors) and [125I][Sar1, Ile8]AII binding to human recombinant AT1 receptors in a concentration-dependent manner with IC50 values of 0.84 ± 0.08 nM and 1.92 ± 0.15 nM, respectively, but did not inhibit specific [125I)AII binding to bovine cerebellum membranes (ÀT2 receptors). In the Scatchard analysis, KR31080 interacted with rabbit aortic AT1 receptors in a competitive manner, similar to losartan. These results demonstrate that KR31080 is a potent and AT1 selective angiotensin receptor antagonist which exerts a competitive antagonism in the [125I]AII binding assay and insurmountable AT1 receptor antagonism in the functional study.  相似文献   
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An inverse relationship between workplace status and morbidity is well established; higher job status has been associated with reduced risks of heart disease, hypertension, and injury. Most research on job status, however, has focused on salaried populations, and it remains unclear whether job status operates similarly among hourly workers. Our objectives were to examine whether hourly status itself influences risk of hypertension after adjustment for socioeconomic confounders, and to explore the role of fine-scale job grade on hypertension incidence within hourly and salaried groups. We examined data for 14,999 aluminum manufacturing employees in 11 plants across the U.S., using logistic regression with adjustment for age, sex, race/ethnicity and other individual characteristics. Propensity score restriction was used to identify comparable groups of hourly and salaried employees, reducing confounding by sociodemographic characteristics. Job grade (coded 1 through 30, within hourly and salaried groups) was examined as a more refined measure of job status. Hourly status was associated with an increased risk of hypertension, after propensity restriction and adjustment for confounders. The observed effect of hourly status was stronger among women, although the propensity-restricted cohort was disproportionately male (96%). Among salaried workers, higher job grade was not consistently associated with decreased risk; among hourly employees, however, there was a significant trend, with higher job grades more protective against hypertension. Increasing the stringency of hypertension case criteria also increased the risk of severe or persistent hypertension for hourly employees.  相似文献   
6.
Clozapine plasma levels were monitored in 16 patients during a series of three consecutive treatments (single dose-multiple dose-single dose). Each patient received a single 75-mg dose (3 x 25 mg) with clozapine tablets, and serial plasma samples were collected over 48 hr after the dose. At 48 hr, a multiple-dose regimen was started, consisting of an initial dose escalation period followed by dosing at a constant regimen for at least 6 days. After the last dose, serial plasma samples were again obtained over 72 hr. Drug was then withheld for at least 7 days, a final single 75-mg dose was given, and plasma sampling was repeated. A subset of the patient population (N = 7) was used to test for a food effect during the single-dose treatments. The pharmacokinetic parameters between the initial and the final single dose periods were not significantly different. Similarly, there were no differences within patients when given the dose after fasting (fed 1 hr after dose) or with a meal. In contrast, the terminal elimination rate differed between the single-dose and the multiple-dose treatments (t1/2 m3 = 7.9 hr single dose and 14.2 hr multiple dose) (P less than 0.05) and the dose-normalized area under the plasma concentration/time curves increased 27% with multiple dosing. Since a previous study in patients (Choc et al., Pharm. Res. 4:402-405, 1987) showed dose proportionality of clozapine plasma concentrations during multiple-dose regimens, the present results cannot be described by Michaelis-Menten kinetics.  相似文献   
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目的 总结造血干细胞移植后慢性移植物抗宿主病(cGVHD)相关的膜性肾病的诊疗体会。方法 为1例急性淋巴细胞白血病患者施行HLA全相合的无关供者外周血造血干细胞移植,术后应用甲氨喋呤和他克莫司(FK506)预防GVHD。术后第19d发生急性GVHD,经甲泼尼龙治疗逆转。分别于术后182d、235d停用FK506和泼尼松,5d后患者出现cGVHD表现,肝功能异常,并伴肾病综合征的相关表现,病理诊断为膜性肾病Ⅱ期,遂给予FK506和泼尼松治疗,同时辅以利尿、降脂等措施。结果发生膜性肾病时,患者的尿蛋白++++,白细胞75个/μl,上皮细胞359.5个/pl,病理性管型+,管型计数为167个/μl,24h尿蛋白定量为4.28g;肾组织活检,无肾小球硬化,肾小球体积稍大,部分血管袢受压,开放欠佳,肾小球基底膜轻微增厚,外观呈僵硬感,系膜基质轻、中度增殖;间质区部分肾小管扩张,肿胀、变性,未见明显间质纤维化和炎症细胞浸润;Masson染色可见基底膜上皮侧嗜复红物沉积;免疫荧光检查,IgG+++,C3+++,IgA++,沿毛细血管袢呈颗粒状节段性分布,系膜区呈团块状分布;IgM、Clq、CA均阴性。电镜下可见肾小球基底膜上皮下沉积物,并有基膜增厚,毛细血管系膜基质轻度增生。经泼尼松和FK506治疗,2个月后尿蛋白转阴。结论 造血干细胞移植后出现肾病综合征或蛋白尿,应考虑GVHD相关膜性肾病的可能,肾穿刺活检有助于诊断,糖皮质激素和FK506治疗有效。  相似文献   
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目的 探讨抗 CD2 5抗体用于预防儿童白血病半匹配未去 T细胞骨髓移植重度移植物抗宿主病 (GVHD)的疗效。 方法  10例儿童白血病患者接受 HL A2 - 3位点不合半匹配骨髓移植 ,移植方法除了供者应用粒细胞集落刺激因子 (GCSF)2 5 0μg促进骨髓及受者应用环孢素 A(CSA ) ,甲氨蝶呤 (MTX) ,抗胸腺细胞球蛋白 (ATG)和霉酚酸酯 (MMF)预防 GVHD综合措施外 ,加用抗 CD2 5单克隆抗体预防 GVHD,剂量各为 2 0 m g,在移植前 2 h和移植后第 4天应用 ,采髓后未去 T细胞输注 ,移植结果与前期未用 Simulect移植组比较。 结果  10例移植后均获造血重建 ,粒细胞大于 0 .5× 10 9/ L 中位天数是19 d,血小板大于 2 0× 10 9/ L 的中位天数是 2 2 d,骨髓植活直接证据检测证实为完全供者造血。无 1例发生急性 ~ GVHD,未用 Sim ulect对照组急性 ~ GVHD为 5 0 % ,差异有显著性意义。可评价慢性 GVHD的 8例均发生慢性 GVHD,均为局限性慢性 GVHD。中位随访 12个月 (范围 9~ 2 4个月 ) ,2例移植相关死亡 ,1例移植后 14个月复发死亡 ,实际无病生存率是 70 % ,与对照比较差异无显著性意义。 结论 本研究儿童半匹配未去 T细胞骨髓移植应用 Sim ulect,明显降低急性重症 a GVHD发生 ,减少移植相关死亡 ,临床应用安全可行。  相似文献   
9.
目的总结1例异基因造血干细胞移植后并发与慢性移植物抗宿主病(cGVHD)相关的多发性肌炎的诊治体会。方法1例急性淋巴细胞白血病患者在处于完全缓解状态下接受同胞间供髓异基因造血干细胞移植,移植后采用环孢素A和甲氨蝶呤预防移植物抗宿主病(GVHD)。结果移植后11 d,WBC>0.5×10~9/L,移植后13 d,血小板>20×10~9/L;27 d时,骨髓细胞染色体分析显示99%为供者型。移植后17 d,发生Ⅰ度急性皮肤型GVHD,经静脉注射地塞米松及甲氨蝶呤后,GVHD被完全控制。移植后8个月,患者发生轻度肝脏cGVHD,经他克莫司及硫唑嘌呤治疗,效果不佳,血清肝酶升高,后改为他克莫司和西罗莫司治疗,血清肝酶逐渐下降,但肌酸激酶从9 U/L上升至272 U/L,随后患者出现全身乏力,并逐渐加重,上下肢近端处活动出现障碍,肌酸激酶升至3010 U/L,股四头肌、肱二头肌的肌电图表现为肌源性损害,双侧大腿磁共振成像符合多发性肌炎表现,给予甲泼尼龙、血浆置换治疗,但无显著效果,患者突发阵发性呼吸困难,经抢救无效,患者死亡,死亡时肌酸激酶为21 010 U/L。结论多发性肌炎为cGVHD的一种较少见形式,累及重要肌组织者预后较差。  相似文献   
10.
Background: There has been a debate about the cost-effectiveness of laparoscopic cholecystectomy (LC), as well as a concern regarding its possible overutilization and changes in the indication for surgery. Methods: A retrospective analysis of all cholecystectomies performed at UCDMC from 1988 to 1994 was done. The annual rate of cholecystectomy increased by 50% in 1990 when LC was introduced but has since stabilized at a rate 11% higher than the rate before LC. The disease status and severity did not change. Results: The incidence of nonelective surgery remained stable at 31.2% to 37.5%. Elective cholecystectomy had lower mortality (0.16% vs 1.8%, P=0.029), morbidity (2.6% vs 11.2%, P=0.0001), and conversion rate (2.6% vs 16%, P=0.0001) and a shorter length of stay (2.1 days vs 5.4 days), compared with nonelective procedure. Conclusions: The indication for surgery in cholelithiasis has not changed since the introduction of LC. In patients with symptomatic gallstones, early elective surgery is recommended and may be more cost-effective.Presented at the annual meeting of the Society of American Gastrointestinal Endoscopic Surgeons (SAGES), Orlando, FL, March 12–14, 1995  相似文献   
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